first commit

LICENSE.md

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 pat-e
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,100 @@
+# AV1 Encoding Scripts
+
+## Overview
+This repository contains Python scripts for batch-processing MKV files to encode video to AV1 and audio to Opus. The scripts prioritize high-quality encoding, handle complex audio track downmixing, VFR (Variable Frame Rate) conversions, and offer features like automatic cropping and resumable encoding.
+
+## Scripts Overview
+
+*   **`aom_opus_encoder.py`**: Uses the `aom` encoder (specifically designed for the `aom-psy101` fork) via `av1an`. It is tuned for high perceptual quality with specific psychovisual parameters and film grain synthesis.
+*   **`svt_opus_encoder.py`**: Uses the `svt-av1` encoder (specifically designed for the `SVT-AV1-Essential` fork) via `av1an`. It provides a good balance between encoding speed and quality, and allows customization of speed, quality, and film-grain presets from the command line.
+
+## Encoding Parameters Documentation
+
+For detailed information on the specific FFmpeg arguments, audio downmixing logic, VFR-to-CFR conversion processes, and the special SVT-AV1/AomEnc parameters used by these scripts, please refer to the [`parameters.md`](parameters.md) file.
+
+## Prerequisites
+
+Both scripts require several external tools to be installed and available in your system's `PATH`:
+
+*   **ffmpeg** & **ffprobe**: For video/audio extraction, filtering (cropdetect), and loudnorm analysis.
+*   **mkvtoolnix** (`mkvmerge`, `mkvpropedit`): For remuxing the final MKV file.
+*   **opusenc** (opus-tools): For encoding audio tracks to the Opus codec.
+*   **mediainfo**: For extracting detailed media information (especially frame rate details).
+*   **av1an**: The core chunking encoder used to run multiple encode workers in parallel.
+*   **HandBrakeCLI**: Used as a fallback/pre-processor to convert VFR (Variable Frame Rate) video to CFR (Constant Frame Rate) before the main encode.
+*   **ffmsindex** (ffms2): For indexing the intermediate UTVideo file for Vapoursynth.
+*   **Vapoursynth**: Required by `av1an` as the frame server via the generated `.vpy` scripts.
+*   *(Specific to `aom_opus_encoder.py`)*: **aom-psy101** encoder. You must download the correct version from [Damian101's aom-psy101 GitLab](https://gitlab.com/damian101/aom-psy101).
+*   *(Specific to `svt_opus_encoder.py`)*: **SVT-AV1-Essential** encoder. You must download the correct version from [nekotrix's SVT-AV1-Essential GitHub](https://github.com/nekotrix/SVT-AV1-Essential/).
+
+## Features
+
+*   **Automated Batch Processing**: Simply place your `.mkv` files in the same directory as the script. The script will process them one by one.
+*   **Resumable Encoding**: Because it uses `av1an`, if an encode is interrupted, you can restart the script, and it will resume from where it left off.
+*   **Audio Normalization and Downmixing**: 
+    *   Extracts audio tracks to FLAC.
+    *   Applies a 2-pass `loudnorm` normalization (Target: -23 LUFS, True Peak: -1 dB).
+    *   Downmixes 5.1/7.1 surround sound to stereo (unless `--no-downmix` is specified).
+    *   Encodes to Opus with bitrates automatically chosen based on the channel count (e.g., 128k for Stereo, 256k for 5.1).
+    *   Directly remuxes existing `aac` or `opus` tracks without re-encoding.
+    *   Preserves track languages, titles, and delays.
+*   **VFR to CFR Conversion**: Detects Variable Frame Rate (VFR) media and automatically converts it to Constant Frame Rate (CFR) using HandBrakeCLI (virtually lossless `x264_10bit` CRF 0 intermediate) to prevent audio desync issues.
+*   **Automatic Cropping**: Optional `--autocrop` flag detects black bars and determines the optimal cropping parameters before encoding.
+*   **Organized Output**: 
+    *   Completed files are moved to a `completed/` directory.
+    *   Original files are moved to an `original/` directory.
+    *   Per-file processing logs are saved in a `conv_logs/` directory.
+    *   Temporary files are automatically cleaned up upon success.
+
+## Usage
+
+Place the script in the directory containing your `.mkv` files and execute it. 
+
+### `aom_opus_encoder.py`
+
+```bash
+python aom_opus_encoder.py [options]
+```
+
+**Options:**
+*   `--no-downmix`: Preserve original audio channel layout (do not downmix 5.1/7.1 to stereo).
+*   `--autocrop`: Automatically detect and crop black bars from the video.
+*   `--grain <int>`: Set the `photon-noise` value for grain synthesis (default: 8).
+*   `--crf <int>`: Set the constant quality level (`cq-level`) for video encoding (default: 28).
+
+### `svt_opus_encoder.py`
+
+```bash
+python svt_opus_encoder.py [options]
+```
+
+**Options:**
+*   `--no-downmix`: Preserve original audio channel layout (do not downmix 5.1/7.1 to stereo).
+*   `--autocrop`: Automatically detect and crop black bars from the video.
+*   `--speed <str>`: Set the SVT-AV1 encoding speed preset (e.g., `slower`, `slow`, `medium`, `fast`, `faster`). Defaults to `slower`.
+*   `--quality <str>`: Set the SVT-AV1 encoding quality preset (e.g., `lowest`, `low`, `medium`, `high`, `higher`). Defaults to `medium`.
+*   `--grain <int>`: Set the `film-grain` value. Adjusts the film grain synthesis level. Defaults to 6.
+
+## Process Workflow
+
+1.  **Preparation**: Scans for `.mkv` files and checks for required tools.
+2.  **Analysis**: Examines video and audio tracks using `ffprobe` and `mediainfo`.
+3.  **Video Processing**:
+    *   Runs crop detection (if `--autocrop` is enabled).
+    *   Converts VFR to CFR (if VFR is detected).
+    *   Extracts an intermediate lossless video (`utvideo`).
+    *   Encodes the video using `av1an`.
+4.  **Audio Processing**:
+    *   Remuxes AAC/Opus.
+    *   Normalizes, downmixes (if applicable), and encodes other formats to Opus.
+5.  **Muxing**: Combines the newly encoded video and audio tracks using `mkvmerge`, preserving synchronization delays, metadata, and languages.
+6.  **Cleanup**: Moves files to respective folders (`completed/`, `original/`) and deletes temporary working files.
+
+## Notes
+
+- Encoding AV1 takes a significant amount of time and CPU resources. 
+- Ensure you have sufficient disk space, as the scripts generate intermediate lossless `utvideo` files which can be very large depending on the length and resolution of the source media.
+
+## License
+
+This project is licensed under the MIT License - see the [`LICENSE.md`](LICENSE.md) file for details.

aom_opus_encoder.py

@@ -0,0 +1,753 @@
+#!/usr/bin/env python3
+"""
+NOTE: This script requires the custom aom-psy101 encoder.
+Please download the correct version from: https://gitlab.com/damian101/aom-psy101
+"""
+import os
+import sys
+import subprocess
+import shutil
+import tempfile
+import json
+import re # Added for VFR frame rate parsing
+from datetime import datetime
+from pathlib import Path
+
+REQUIRED_TOOLS = [
+    "ffmpeg", "ffprobe", "mkvmerge", "mkvpropedit",
+    "opusenc", "mediainfo", "av1an", "HandBrakeCLI", "ffmsindex" # Added HandBrakeCLI and ffmsindex
+]
+DIR_COMPLETED = Path("completed")
+DIR_ORIGINAL = Path("original")
+DIR_CONV_LOGS = Path("conv_logs") # Directory for conversion logs
+
+REMUX_CODECS = {"aac", "opus"}  # Using a set for efficient lookups
+
+
+def check_tools():
+    for tool in REQUIRED_TOOLS:
+        if shutil.which(tool) is None:
+            print(f"Required tool '{tool}' not found in PATH.")
+            sys.exit(1)
+
+def run_cmd(cmd, capture_output=False, check=True):
+    if capture_output:
+        result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, check=check, text=True)
+        return result.stdout
+    else:
+        subprocess.run(cmd, check=check)
+
+def convert_audio_track(index, ch, lang, audio_temp_dir, source_file, should_downmix):
+    audio_temp_path = Path(audio_temp_dir)
+    temp_extracted = audio_temp_path / f"track_{index}_extracted.flac"
+    temp_normalized = audio_temp_path / f"track_{index}_normalized.flac"
+    final_opus = audio_temp_path / f"track_{index}_final.opus"
+
+    print(f"    - Extracting Audio Track #{index} to FLAC...")
+    ffmpeg_args = [
+        "ffmpeg", "-v", "quiet", "-stats", "-y", "-i", str(source_file), "-map", f"0:{index}", "-map_metadata", "-1"
+    ]
+    if should_downmix and ch >= 6:
+        if ch == 6:
+            ffmpeg_args += ["-af", "pan=stereo|c0=c2+0.30*c0+0.30*c4|c1=c2+0.30*c1+0.30*c5"]
+        elif ch == 8:
+            ffmpeg_args += ["-af", "pan=stereo|c0=c2+0.30*c0+0.30*c4+0.30*c6|c1=c2+0.30*c1+0.30*c5+0.30*c7"]
+        else: # Other multi-channel (e.g. 7ch, 10ch)
+            ffmpeg_args += ["-ac", "2"]
+    ffmpeg_args += ["-c:a", "flac", str(temp_extracted)]
+    run_cmd(ffmpeg_args)
+
+    print(f"    - Normalizing Audio Track #{index} with ffmpeg (loudnorm 2-pass)...")
+    # First pass: Analyze the audio to get loudnorm stats
+    # The stats are printed to stderr, so we must use subprocess.run directly to capture it.
+    print("      - Pass 1: Analyzing...")
+    result = subprocess.run(
+        ["ffmpeg", "-v", "info", "-i", str(temp_extracted), "-af", "loudnorm=I=-23:LRA=7:tp=-1:print_format=json", "-f", "null", "-"],
+        capture_output=True, text=True, check=True)
+    
+    # Find the start of the JSON block in stderr and parse it.
+    # This is more robust than slicing the last N lines.
+    # We find the start and end of the JSON block to avoid parsing extra data.
+    stderr_output = result.stderr
+    json_start_index = stderr_output.find('{')
+    if json_start_index == -1:
+        raise ValueError("Could not find start of JSON block in ffmpeg output for loudnorm analysis.")
+
+    brace_level = 0
+    json_end_index = -1
+    for i, char in enumerate(stderr_output[json_start_index:]):
+        if char == '{':
+            brace_level += 1
+        elif char == '}':
+            brace_level -= 1
+            if brace_level == 0:
+                json_end_index = json_start_index + i + 1
+                break
+    
+    stats = json.loads(stderr_output[json_start_index:json_end_index])
+
+    # Second pass: Apply the normalization using the stats from the first pass
+    print("      - Pass 2: Applying normalization...")
+    run_cmd([
+        "ffmpeg", "-v", "quiet", "-stats", "-y", "-i", str(temp_extracted), "-af",
+        f"loudnorm=I=-23:LRA=7:tp=-1:measured_i={stats['input_i']}:measured_lra={stats['input_lra']}:measured_tp={stats['input_tp']}:measured_thresh={stats['input_thresh']}:offset={stats['target_offset']}",
+        "-c:a", "flac", str(temp_normalized)
+    ])
+
+    # Set bitrate based on the final channel count of the Opus file.
+    # If we are downmixing, the result is stereo.
+    # If not, the result has the original channel count.
+    is_being_downmixed = should_downmix and ch >= 6
+
+    if is_being_downmixed:
+        # Downmixing from 5.1 or 7.1 results in a stereo track.
+        bitrate = "128k"
+    else:
+        # Not downmixing (or source is already stereo or less).
+        # Base bitrate on the source channel count.
+        if ch == 1:      # Mono
+            bitrate = "64k"
+        elif ch == 2:    # Stereo
+            bitrate = "128k"
+        elif ch == 6:    # 5.1 Surround
+            bitrate = "256k"
+        elif ch == 8:    # 7.1 Surround
+            bitrate = "384k"
+        else:            # Other layouts
+            bitrate = "192k" # A sensible default for other/uncommon layouts.
+
+    print(f"    - Encoding Audio Track #{index} to Opus at {bitrate}...")
+    run_cmd([
+        "opusenc", "--vbr", "--bitrate", bitrate, str(temp_normalized), str(final_opus)
+    ])
+    return final_opus
+
+def convert_video(source_file_base, source_file_full, is_vfr, target_cfr_fps_for_handbrake, autocrop_filter=None, grain=8, crf=28):
+    print("  --- Starting Video Processing ---")
+    # source_file_base is file_path.stem (e.g., "my.anime.episode.01")
+    vpy_file = Path(f"{source_file_base}.vpy")
+    ut_video_file = Path(f"{source_file_base}.ut.mkv")
+    encoded_video_file = Path(f"temp-{source_file_base}.mkv")
+    handbrake_cfr_intermediate_file = None # To store path of HandBrake output if created
+
+    current_input_for_utvideo = Path(source_file_full)
+
+    if is_vfr and target_cfr_fps_for_handbrake:
+        print(f"    - Source is VFR. Converting to CFR ({target_cfr_fps_for_handbrake}) with HandBrakeCLI...")
+        handbrake_cfr_intermediate_file = Path(f"{source_file_base}.cfr_temp.mkv")
+        handbrake_args = [
+            "HandBrakeCLI", 
+            "--input", str(source_file_full), 
+            "--output", str(handbrake_cfr_intermediate_file),
+            "--cfr", 
+            "--rate", str(target_cfr_fps_for_handbrake),
+            "--encoder", "x264_10bit", # Changed to x264_10bit for 10-bit CFR intermediate
+            "--quality", "0", # CRF 0 for x264 is often considered visually lossless, or near-lossless
+            "--encoder-preset", "superfast", # Use a fast preset for quicker processing
+            "--encoder-tune", "fastdecode", # Added tune for faster decoding
+            "--audio", "none", 
+            "--subtitle", "none",
+            "--crop-mode", "none" # Disable auto-cropping
+        ]
+        print(f"    - Running HandBrakeCLI: {' '.join(handbrake_args)}")
+        try:
+            run_cmd(handbrake_args)
+            if handbrake_cfr_intermediate_file.exists() and handbrake_cfr_intermediate_file.stat().st_size > 0:
+                print(f"    - HandBrake VFR to CFR conversion successful: {handbrake_cfr_intermediate_file}")
+                current_input_for_utvideo = handbrake_cfr_intermediate_file
+            else:
+                print(f"    - Warning: HandBrakeCLI VFR-to-CFR conversion failed or produced an empty file. Proceeding with original source for UTVideo.")
+                handbrake_cfr_intermediate_file = None # Ensure it's None if failed
+        except subprocess.CalledProcessError as e:
+            print(f"    - Error during HandBrakeCLI execution: {e}")
+            print(f"    - Proceeding with original source for UTVideo.")
+            handbrake_cfr_intermediate_file = None # Ensure it's None if failed
+
+
+    print("    - Creating UTVideo intermediate file (overwriting if exists)...")
+    # Check if source is already UTVideo
+    ffprobe_cmd = [
+        "ffprobe", "-v", "error", "-select_streams", "v:0",
+        "-show_entries", "stream=codec_name", "-of", "default=noprint_wrappers=1:nokey=1",
+        str(current_input_for_utvideo) # Use current input, which might be HandBrake output
+    ]
+    source_codec = run_cmd(ffprobe_cmd, capture_output=True, check=True).strip()
+
+    video_codec_args = ["-c:v", "utvideo"]
+    if source_codec == "utvideo" and current_input_for_utvideo == Path(source_file_full): # Only copy if original was UTVideo
+        print("    - Source is already UTVideo. Copying video stream...")
+        video_codec_args = ["-c:v", "copy"]
+
+    ffmpeg_args = [
+        "ffmpeg", "-hide_banner", "-v", "quiet", "-stats", "-y", "-i", str(current_input_for_utvideo),
+        "-map", "0:v:0", "-map_metadata", "-1", "-map_chapters", "-1", "-an", "-sn", "-dn",
+    ]
+    if autocrop_filter:
+        ffmpeg_args += ["-vf", autocrop_filter]
+    ffmpeg_args += video_codec_args + [str(ut_video_file)]
+    run_cmd(ffmpeg_args)
+
+    print("    - Indexing UTVideo file with ffmsindex for VapourSynth...")
+    ffmsindex_args = ["ffmsindex", "-f", str(ut_video_file)]
+    run_cmd(ffmsindex_args)
+
+    ut_video_full_path = os.path.abspath(ut_video_file)
+    vpy_script_content = f"""import vapoursynth as vs
+core = vs.core
+core.num_threads = 4
+clip = core.ffms2.Source(source=r'''{ut_video_full_path}''')
+clip = core.resize.Point(clip, format=vs.YUV420P10, matrix_in_s="709") # type: ignore
+clip.set_output()
+"""
+    with vpy_file.open("w", encoding="utf-8") as f:
+        f.write(vpy_script_content)
+
+    print("    - Starting AV1 encode with av1an (this will take a long time)...")
+    total_cores = os.cpu_count() or 4 # Fallback if cpu_count is None
+    workers = max(1, (total_cores // 2) - 1) # Half the cores minus one, with a minimum of 1 worker.
+    print(f"    - Using {workers} workers for av1an (Total Cores: {total_cores}, Logic: (Cores/2)-1).")
+
+    aom_video_params_str = f" --bit-depth=10 --cpu-used=2 --end-usage=q --cq-level={crf} --min-q=6 --threads=2 --tune-content=psy --frame-parallel=1 --tile-columns=1 --gf-max-pyr-height=4 --deltaq-mode=2 --enable-keyframe-filtering=0 --disable-kf --enable-fwd-kf=0 --kf-max-dist=9999 --sb-size=dynamic --enable-chroma-deltaq=1 --enable-qm=1 --color-primaries=bt709 --transfer-characteristics=bt709 --matrix-coefficients=bt709 "
+
+    av1an_enc_args = [
+        "av1an", "-i", str(vpy_file), "-o", str(encoded_video_file), "-n",
+        "-e", "aom", "--photon-noise", str(grain), "--resume", "--sc-pix-format", "yuv420p", "-c", "mkvmerge",
+        "--set-thread-affinity", "2", "--pix-format", "yuv420p10le", "--force", "--no-defaults",
+        "-w", str(workers), "--passes", "2",
+        "-v", aom_video_params_str
+    ]
+    print(f"    - Using aom-psy101 parameters: {aom_video_params_str}")
+    run_cmd(av1an_enc_args)
+    print("  --- Finished Video Processing ---")
+    return encoded_video_file, handbrake_cfr_intermediate_file
+
+def is_ffmpeg_decodable(file_path):
+    """Quickly check if ffmpeg can decode the input file."""
+    try:
+        # Try to decode a short segment of the first audio stream
+        subprocess.run([
+            "ffmpeg", "-v", "error", "-i", str(file_path), "-map", "0:a:0", "-t", "1", "-f", "null", "-"
+        ], check=True)
+        return True
+    except subprocess.CalledProcessError:
+        return False
+
+# --- CROPDETECT LOGIC FROM cropdetect.py ---
+import argparse as _argparse_cropdetect
+import multiprocessing as _multiprocessing_cropdetect
+from collections import Counter as _Counter_cropdetect
+
+COLOR_GREEN = "\033[92m"
+COLOR_RED = "\033[91m"
+COLOR_YELLOW = "\033[93m"
+COLOR_RESET = "\033[0m"
+
+KNOWN_ASPECT_RATIOS = [
+    {"name": "HDTV (16:9)", "ratio": 16/9},
+    {"name": "Widescreen (Scope)", "ratio": 2.39},
+    {"name": "Widescreen (Flat)", "ratio": 1.85},
+    {"name": "IMAX Digital (1.90:1)", "ratio": 1.90},
+    {"name": "Fullscreen (4:3)", "ratio": 4/3},
+    {"name": "IMAX 70mm (1.43:1)", "ratio": 1.43},
+]
+
+def _check_prerequisites_cropdetect():
+    for tool in ['ffmpeg', 'ffprobe']:
+        if not shutil.which(tool):
+            print(f"Error: '{tool}' command not found. Is it installed and in your PATH?")
+            return False
+    return True
+
+def _analyze_segment_cropdetect(task_args):
+    seek_time, input_file, width, height = task_args
+    ffmpeg_args = [
+        'ffmpeg', '-hide_banner',
+        '-ss', str(seek_time),
+        '-i', input_file, '-t', '1', '-vf', 'cropdetect',
+        '-f', 'null', '-'
+    ]
+    result = subprocess.run(ffmpeg_args, capture_output=True, text=True, encoding='utf-8')
+    if result.returncode != 0:
+        return []
+    crop_detections = re.findall(r'crop=(\d+):(\d+):(\d+):(\d+)', result.stderr)
+    significant_crops = []
+    for w_str, h_str, x_str, y_str in crop_detections:
+        w, h, x, y = map(int, [w_str, h_str, x_str, y_str])
+        significant_crops.append((f"crop={w}:{h}:{x}:{y}", seek_time))
+    return significant_crops
+
+def _snap_to_known_ar_cropdetect(w, h, x, y, video_w, video_h, tolerance=0.03):
+    if h == 0: return f"crop={w}:{h}:{x}:{y}", None
+    detected_ratio = w / h
+    best_match = None
+    smallest_diff = float('inf')
+    for ar in KNOWN_ASPECT_RATIOS:
+        diff = abs(detected_ratio - ar['ratio'])
+        if diff < smallest_diff:
+            smallest_diff = diff
+            best_match = ar
+    if not best_match or (smallest_diff / best_match['ratio']) >= tolerance:
+        return f"crop={w}:{h}:{x}:{y}", None
+    if abs(w - video_w) < 16:
+        new_h = round(video_w / best_match['ratio'])
+        if new_h % 8 != 0:
+            new_h = new_h + (8 - (new_h % 8))
+        new_h = min(new_h, video_h)
+        new_y = round((video_h - new_h) / 2)
+        if new_y % 2 != 0:
+            new_y -= 1
+        new_y = max(0, new_y)
+        return f"crop={video_w}:{new_h}:0:{new_y}", best_match['name']
+    if abs(h - video_h) < 16:
+        new_w = round(video_h * best_match['ratio'])
+        if new_w % 8 != 0:
+            new_w = new_w + (8 - (new_w % 8))
+        new_w = min(new_w, video_w)
+        new_x = round((video_w - new_w) / 2)
+        if new_x % 2 != 0:
+            new_x -= 1
+        new_x = max(0, new_x)
+        return f"crop={new_w}:{video_h}:{new_x}:0", best_match['name']
+    return f"crop={w}:{h}:{x}:{y}", None
+
+def _cluster_crop_values_cropdetect(crop_counts, tolerance=8):
+    clusters = []
+    temp_counts = crop_counts.copy()
+    while temp_counts:
+        center_str, _ = temp_counts.most_common(1)[0]
+        try:
+            _, values = center_str.split('=');
+            cw, ch, cx, cy = map(int, values.split(':'))
+        except (ValueError, IndexError):
+            del temp_counts[center_str]
+            continue
+        cluster_total_count = 0
+        crops_to_remove = []
+        for crop_str, count in temp_counts.items():
+            try:
+                _, values = crop_str.split('=');
+                w, h, x, y = map(int, values.split(':'))
+                if abs(x - cx) <= tolerance and abs(y - cy) <= tolerance:
+                    cluster_total_count += count
+                    crops_to_remove.append(crop_str)
+            except (ValueError, IndexError):
+                continue
+        if cluster_total_count > 0:
+            clusters.append({'center': center_str, 'count': cluster_total_count})
+        for crop_str in crops_to_remove:
+            del temp_counts[crop_str]
+    clusters.sort(key=lambda c: c['count'], reverse=True)
+    return clusters
+
+def _parse_crop_string_cropdetect(crop_str):
+    try:
+        _, values = crop_str.split('=');
+        w, h, x, y = map(int, values.split(':'))
+        return {'w': w, 'h': h, 'x': x, 'y': y}
+    except (ValueError, IndexError):
+        return None
+
+def _calculate_bounding_box_cropdetect(crop_keys):
+    min_x = min_w = min_y = min_h = float('inf')
+    max_x = max_w = max_y = max_h = float('-inf')
+    for key in crop_keys:
+        parsed = _parse_crop_string_cropdetect(key)
+        if not parsed:
+            continue
+        w, h, x, y = parsed['w'], parsed['h'], parsed['x'], parsed['y']
+        min_x = min(min_x, x)
+        min_y = min(min_y, y)
+        max_x = max(max_x, x + w)
+        max_y = max(max_y, y + h)
+        min_w = min(min_w, w)
+        min_h = min(min_h, h)
+        max_w = max(max_w, w)
+        max_h = max(max_h, h)
+    if (max_x - min_x) <= 2 and (max_y - min_y) <= 2:
+        return None
+    bounding_crop = f"crop={max_x - min_x}:{max_y - min_y}:{min_x}:{min_y}"
+    return bounding_crop
+
+def _analyze_video_cropdetect(input_file, duration, width, height, num_workers, significant_crop_threshold, min_crop, debug=False):
+    num_tasks = num_workers * 4
+    segment_duration = max(1, duration // num_tasks)
+    tasks = [(i * segment_duration, input_file, width, height) for i in range(num_tasks)]
+    crop_results = []
+    with _multiprocessing_cropdetect.Pool(processes=num_workers) as pool:
+        results_iterator = pool.imap_unordered(_analyze_segment_cropdetect, tasks)
+        for result in results_iterator:
+            crop_results.append(result)
+    all_crops_with_ts = [crop for sublist in crop_results for crop in sublist]
+    all_crop_strings = [item[0] for item in all_crops_with_ts]
+    if not all_crop_strings:
+        return None
+    crop_counts = _Counter_cropdetect(all_crop_strings)
+    clusters = _cluster_crop_values_cropdetect(crop_counts)
+    total_detections = sum(c['count'] for c in clusters)
+    significant_clusters = []
+    for cluster in clusters:
+        percentage = (cluster['count'] / total_detections) * 100
+        if percentage >= significant_crop_threshold:
+            significant_clusters.append(cluster)
+    for cluster in significant_clusters:
+        parsed_crop = _parse_crop_string_cropdetect(cluster['center'])
+        if parsed_crop:
+            _, ar_label = _snap_to_known_ar_cropdetect(
+                parsed_crop['w'], parsed_crop['h'], parsed_crop['x'], parsed_crop['y'], width, height
+            )
+            cluster['ar_label'] = ar_label
+        else:
+            cluster['ar_label'] = None
+    if not significant_clusters:
+        return None
+    elif len(significant_clusters) == 1:
+        dominant_cluster = significant_clusters[0]
+        parsed_crop = _parse_crop_string_cropdetect(dominant_cluster['center'])
+        snapped_crop, ar_label = _snap_to_known_ar_cropdetect(
+            parsed_crop['w'], parsed_crop['h'], parsed_crop['x'], parsed_crop['y'], width, height
+        )
+        parsed_snapped = _parse_crop_string_cropdetect(snapped_crop)
+        if parsed_snapped and parsed_snapped['w'] == width and parsed_snapped['h'] == height:
+            return None
+        else:
+            return snapped_crop
+    else:
+        crop_keys = [c['center'] for c in significant_clusters]
+        bounding_box_crop = _calculate_bounding_box_cropdetect(crop_keys)
+        if bounding_box_crop:
+            parsed_bb = _parse_crop_string_cropdetect(bounding_box_crop)
+            snapped_crop, ar_label = _snap_to_known_ar_cropdetect(
+                parsed_bb['w'], parsed_bb['h'], parsed_bb['x'], parsed_bb['y'], width, height
+            )
+            parsed_snapped = _parse_crop_string_cropdetect(snapped_crop)
+            if parsed_snapped and parsed_snapped['w'] == width and parsed_snapped['h'] == height:
+                return None
+            else:
+                return snapped_crop
+        else:
+            return None
+
+def detect_autocrop_filter(input_file, significant_crop_threshold=5.0, min_crop=10, debug=False):
+    if not _check_prerequisites_cropdetect():
+        return None
+    try:
+        probe_duration_args = [
+            'ffprobe', '-v', 'error', '-show_entries', 'format=duration', '-of', 'default=noprint_wrappers=1:nokey=1',
+            input_file
+        ]
+        duration_str = subprocess.check_output(probe_duration_args, stderr=subprocess.STDOUT, text=True)
+        duration = int(float(duration_str))
+        probe_res_args = [
+            'ffprobe', '-v', 'error',
+            '-select_streams', 'v',
+            '-show_entries', 'stream=width,height,disposition',
+            '-of', 'json',
+            input_file
+        ]
+        probe_output = subprocess.check_output(probe_res_args, stderr=subprocess.STDOUT, text=True)
+        streams_data = json.loads(probe_output)
+        video_stream = None
+        for stream in streams_data.get('streams', []):
+            if stream.get('disposition', {}).get('attached_pic', 0) == 0:
+                video_stream = stream
+                break
+        if not video_stream or 'width' not in video_stream or 'height' not in video_stream:
+            return None
+        width = int(video_stream['width'])
+        height = int(video_stream['height'])
+    except Exception:
+        return None
+    return _analyze_video_cropdetect(input_file, duration, width, height, max(1, os.cpu_count() // 2), significant_crop_threshold, min_crop, debug)
+
+def main(no_downmix=False, autocrop=False, grain=8, crf=28):
+    check_tools()
+
+    current_dir = Path(".")
+    files_to_process = sorted(
+        f for f in current_dir.glob("*.mkv")
+        if not (f.name.endswith(".ut.mkv") or f.name.startswith("temp-") or f.name.startswith("output-") or f.name.endswith(".cfr_temp.mkv"))
+    )
+    if not files_to_process:
+        print("No MKV files found to process. Exiting.")
+        return
+    DIR_COMPLETED.mkdir(exist_ok=True, parents=True)
+    DIR_ORIGINAL.mkdir(exist_ok=True, parents=True)
+    DIR_CONV_LOGS.mkdir(exist_ok=True, parents=True)
+    while True:
+        files_to_process = sorted(
+            f for f in current_dir.glob("*.mkv")
+            if not (f.name.endswith(".ut.mkv") or f.name.startswith("temp-") or f.name.startswith("output-") or f.name.endswith(".cfr_temp.mkv"))
+        )
+        if not files_to_process:
+            print("No more .mkv files found to process in the current directory. The script will now exit.")
+            break
+        file_path = files_to_process[0]
+        if not is_ffmpeg_decodable(file_path):
+            print(f"ERROR: ffmpeg cannot decode '{file_path.name}'. Skipping this file.", file=sys.stderr)
+            shutil.move(str(file_path), DIR_ORIGINAL / file_path.name)
+            continue
+        print("-" * shutil.get_terminal_size(fallback=(80, 24)).columns)
+        log_file_name = f"{file_path.stem}.log"
+        log_file_path = DIR_CONV_LOGS / log_file_name
+        original_stdout_console = sys.stdout
+        original_stderr_console = sys.stderr
+        print(f"Processing: {file_path.name}", file=original_stdout_console)
+        print(f"Logging output to: {log_file_path}", file=original_stdout_console)
+        log_file_handle = None
+        processing_error_occurred = False
+        date_for_runtime_calc = datetime.now()
+        try:
+            log_file_handle = open(log_file_path, 'w', encoding='utf-8')
+            sys.stdout = log_file_handle
+            sys.stderr = log_file_handle
+            print(f"STARTING LOG FOR: {file_path.name}")
+            print(f"Processing started at: {date_for_runtime_calc}")
+            print(f"Full input file path: {file_path.resolve()}")
+            print("-" * shutil.get_terminal_size(fallback=(80, 24)).columns)
+            input_file_abs = file_path.resolve()
+            intermediate_output_file = current_dir / f"output-{file_path.name}"
+            audio_temp_dir = None
+            handbrake_intermediate_for_cleanup = None
+            try:
+                audio_temp_dir = tempfile.mkdtemp(prefix="anime_audio_")
+                print(f"Audio temporary directory created at: {audio_temp_dir}")
+                print(f"Analyzing file: {input_file_abs}")
+                ffprobe_info_json = run_cmd([
+                    "ffprobe", "-v", "quiet", "-print_format", "json", "-show_streams", "-show_format", str(input_file_abs)
+                ], capture_output=True)
+                ffprobe_info = json.loads(ffprobe_info_json)
+                mkvmerge_info_json = run_cmd([
+                    "mkvmerge", "-J", str(input_file_abs)
+                ], capture_output=True)
+                mkv_info = json.loads(mkvmerge_info_json)
+                mediainfo_json = run_cmd([
+                    "mediainfo", "--Output=JSON", "-f", str(input_file_abs)
+                ], capture_output=True)
+                media_info = json.loads(mediainfo_json)
+                is_vfr = False
+                target_cfr_fps_for_handbrake = None
+                video_track_info = None
+                if media_info.get("media") and media_info["media"].get("track"):
+                    for track in media_info["media"]["track"]:
+                        if track.get("@type") == "Video":
+                            video_track_info = track
+                            break
+                if video_track_info:
+                    frame_rate_mode = video_track_info.get("FrameRate_Mode")
+                    if frame_rate_mode and frame_rate_mode.upper() in ["VFR", "VARIABLE"]:
+                        is_vfr = True
+                        print(f"    - Detected VFR based on MediaInfo FrameRate_Mode: {frame_rate_mode}")
+                        original_fps_str = video_track_info.get("FrameRate_Original_String")
+                        if original_fps_str:
+                            match = re.search(r'\((\d+/\d+)\)', original_fps_str)
+                            if match:
+                                target_cfr_fps_for_handbrake = match.group(1)
+                            else:
+                                target_cfr_fps_for_handbrake = video_track_info.get("FrameRate_Original")
+                        if not target_cfr_fps_for_handbrake:
+                            target_cfr_fps_for_handbrake = video_track_info.get("FrameRate_Original")
+                        if not target_cfr_fps_for_handbrake:
+                            target_cfr_fps_for_handbrake = video_track_info.get("FrameRate")
+                            if target_cfr_fps_for_handbrake:
+                                print(f"    - Using MediaInfo FrameRate ({target_cfr_fps_for_handbrake}) as fallback for HandBrake target FPS.")
+                        if target_cfr_fps_for_handbrake:
+                            print(f"    - Target CFR for HandBrake: {target_cfr_fps_for_handbrake}")
+                            if isinstance(target_cfr_fps_for_handbrake, str) and "/" in target_cfr_fps_for_handbrake:
+                                try:
+                                    num, den = map(float, target_cfr_fps_for_handbrake.split('/'))
+                                    target_cfr_fps_for_handbrake = f"{num / den:.3f}"
+                                    print(f"    - Converted fractional FPS to decimal for HandBrake: {target_cfr_fps_for_handbrake}")
+                                except ValueError:
+                                    print(f"    - Warning: Could not parse fractional FPS '{target_cfr_fps_for_handbrake}'. HandBrakeCLI might fail.")
+                                    is_vfr = False
+                        else:
+                            print("    - Warning: VFR detected, but could not determine target CFR from MediaInfo. Will attempt standard UTVideo conversion without HandBrake.")
+                            is_vfr = False
+                    else:
+                        print(f"    - Video appears to be CFR or FrameRate_Mode not specified as VFR/Variable by MediaInfo.")
+                autocrop_filter = None
+                if autocrop:
+                    print("--- Running autocrop detection ---")
+                    autocrop_filter = detect_autocrop_filter(str(input_file_abs))
+                    if autocrop_filter:
+                        print(f"    - Autocrop filter detected: {autocrop_filter}")
+                    else:
+                        print("    - No crop needed or detected.")
+                encoded_video_file, handbrake_intermediate_for_cleanup = convert_video(
+                    file_path.stem, str(input_file_abs), is_vfr, target_cfr_fps_for_handbrake, autocrop_filter=autocrop_filter, grain=grain, crf=crf
+                )
+
+                print("--- Starting Audio Processing ---")
+                processed_audio_files = []
+                audio_tracks_to_remux = []
+                audio_streams = [s for s in ffprobe_info.get("streams", []) if s.get("codec_type") == "audio"]
+
+                # Build mkvmerge track mapping by track ID
+                mkv_audio_tracks = {t["id"]: t for t in mkv_info.get("tracks", []) if t.get("type") == "audio"}
+
+                # Build mediainfo track mapping by StreamOrder
+                media_tracks_data = media_info.get("media", {}).get("track", [])
+                mediainfo_audio_tracks = {int(t.get("StreamOrder", -1)): t for t in media_tracks_data if t.get("@type") == "Audio"}
+
+                for stream in audio_streams:
+                    stream_index = stream["index"]
+                    codec = stream.get("codec_name")
+                    channels = stream.get("channels", 2)
+                    language = stream.get("tags", {}).get("language", "und")
+
+                    # Find mkvmerge track by matching ffprobe stream index to mkvmerge track's 'properties'->'stream_id'
+                    mkv_track = None
+                    for t in mkv_info.get("tracks", []):
+                        if t.get("type") == "audio" and t.get("properties", {}).get("stream_id") == stream_index:
+                            mkv_track = t
+                            break
+                    if not mkv_track:
+                        # Fallback: try by position
+                        mkv_track = mkv_info.get("tracks", [])[stream_index] if stream_index < len(mkv_info.get("tracks", [])) else {}
+
+                    track_id = mkv_track.get("id", -1)
+                    track_title = mkv_track.get("properties", {}).get("track_name", "")
+
+                    # Find mediainfo track by StreamOrder
+                    audio_track_info = mediainfo_audio_tracks.get(stream_index)
+                    track_delay = 0
+                    delay_raw = audio_track_info.get("Video_Delay") if audio_track_info else None
+                    if delay_raw is not None:
+                        try:
+                            delay_val = float(delay_raw)
+                            # If the value is a float < 1, it's seconds, so convert to ms.
+                            if delay_val < 1:
+                                track_delay = int(round(delay_val * 1000))
+                            else:
+                                track_delay = int(round(delay_val))
+                        except Exception:
+                            track_delay = 0
+
+                    print(f"Processing Audio Stream #{stream_index} (TID: {track_id}, Codec: {codec}, Channels: {channels})")
+                    if codec in REMUX_CODECS:
+                        audio_tracks_to_remux.append(str(track_id))
+                    else:
+                        # Convert any codec that is not in REMUX_CODECS
+                        opus_file = convert_audio_track(
+                            stream_index, channels, language, audio_temp_dir, str(input_file_abs), not no_downmix
+                        )
+                        processed_audio_files.append({
+                            "Path": opus_file,
+                            "Language": language,
+                            "Title": track_title,
+                            "Delay": track_delay
+                        })
+
+                print("--- Finished Audio Processing ---")
+
+                # Final mux
+                print("Assembling final file with mkvmerge...")
+                mkvmerge_args = ["mkvmerge", "-o", str(intermediate_output_file), str(encoded_video_file)]
+                for file_info in processed_audio_files:
+                    sync_switch = ["--sync", f"0:{file_info['Delay']}"] if file_info["Delay"] else []
+                    mkvmerge_args += [
+                        "--language", f"0:{file_info['Language']}",
+                        "--track-name", f"0:{file_info['Title']}"
+                    ] + sync_switch + [str(file_info["Path"])]
+
+                source_copy_args = ["--no-video"]
+                if audio_tracks_to_remux:
+                    source_copy_args += ["--audio-tracks", ",".join(audio_tracks_to_remux)]
+                else:
+                    source_copy_args += ["--no-audio"]
+                mkvmerge_args += source_copy_args + [str(input_file_abs)]
+                run_cmd(mkvmerge_args)
+
+                # Move files
+                print("Moving files to final destinations...")
+                shutil.move(str(file_path), DIR_ORIGINAL / file_path.name)
+                shutil.move(str(intermediate_output_file), DIR_COMPLETED / file_path.name)
+
+                print("Cleaning up persistent video temporary files (after successful processing)...")
+                video_temp_files_on_success = [
+                    current_dir / f"{file_path.stem}.vpy",
+                    current_dir / f"{file_path.stem}.ut.mkv",
+                    current_dir / f"temp-{file_path.stem}.mkv", # This is encoded_video_file
+                    current_dir / f"{file_path.stem}.ut.mkv.lwi", 
+                    current_dir / f"{file_path.stem}.ut.mkv.ffindex",
+                ]
+                if handbrake_intermediate_for_cleanup and handbrake_intermediate_for_cleanup.exists():
+                    video_temp_files_on_success.append(handbrake_intermediate_for_cleanup)
+                
+                for temp_vid_file in video_temp_files_on_success:
+                    if temp_vid_file.exists():
+                        print(f"    Deleting: {temp_vid_file}")
+                        temp_vid_file.unlink(missing_ok=True)
+                    else:
+                        print(f"    Skipping (not found): {temp_vid_file}")
+
+            except Exception as e:
+                print(f"ERROR: An error occurred while processing '{file_path.name}': {e}", file=sys.stderr) # Goes to log
+                original_stderr_console.write(f"ERROR during processing of '{file_path.name}': {e}\nSee log '{log_file_path}' for details.\n")
+                processing_error_occurred = True
+            finally:
+                # This is the original 'finally' block. Its prints go to the log file.
+                print("--- Starting Universal Cleanup (for this file) ---")
+                print("  - Cleaning up disposable audio temporary directory...")
+                if audio_temp_dir and Path(audio_temp_dir).exists():
+                    shutil.rmtree(audio_temp_dir, ignore_errors=True)
+                    print(f"    - Deleted audio temp dir: {audio_temp_dir}")
+                elif audio_temp_dir: # Was created but now not found
+                    print(f"    - Audio temp dir not found or already cleaned: {audio_temp_dir}")
+                else: # Was never created
+                    print(f"    - Audio temp dir was not created.")
+                
+                print("  - Cleaning up intermediate output file (if it wasn't moved on success)...")
+                if intermediate_output_file.exists(): # Check if it still exists (e.g. error before move)
+                    if processing_error_occurred:
+                        print(f"    - WARNING: Processing error occurred. Intermediate output file '{intermediate_output_file}' is being preserved at its original path for inspection.")
+                    else:
+                        # No processing error, so it should have been moved.
+                        # If it's still here, it's unexpected but we'll clean it up.
+                        print(f"    - INFO: Intermediate output file '{intermediate_output_file}' found at original path despite no errors (expected to be moved). Cleaning up.")
+                        intermediate_output_file.unlink(missing_ok=True) # Only unlink if no error and it exists
+                        print(f"    - Deleted intermediate output file from original path: {intermediate_output_file}")
+                else:
+                    # File does not exist at original path
+                    if not processing_error_occurred:
+                        print(f"    - Intermediate output file successfully moved (not found at original path, as expected): {intermediate_output_file}")
+                    else:
+                        print(f"    - Processing error occurred, and intermediate output file '{intermediate_output_file}' not found at original path (likely not created or cleaned by another step).")
+            # --- End of original per-file processing block ---
+
+            print(f"FINISHED LOG FOR: {file_path.name}")
+            # --- End of log-specific messages ---
+
+        finally: # Outer finally for restoring stdout/stderr and closing log file
+            runtime = datetime.now() - date_for_runtime_calc
+            runtime_str = str(runtime).split('.')[0]
+            
+            # This print goes to the log file, as stdout is not yet restored.
+            print(f"\nTotal runtime for this file: {runtime_str}")
+            
+            if sys.stdout != original_stdout_console:
+                sys.stdout = original_stdout_console
+            if sys.stderr != original_stderr_console:
+                sys.stderr = original_stderr_console
+            if log_file_handle:
+                log_file_handle.close()
+            
+            # Announce to console (original stdout/stderr) that this file is done
+            if processing_error_occurred:
+                original_stderr_console.write(f"File: {file_path.name}\n")
+                original_stderr_console.write(f"Log: {log_file_path}\n")
+                original_stderr_console.write(f"Runtime: {runtime_str}\n")
+            else:
+                original_stdout_console.write(f"File: {file_path.name}\n")
+                original_stdout_console.write(f"Log: {log_file_path}\n")
+                original_stdout_console.write(f"Runtime: {runtime_str}\n")
+
+if __name__ == "__main__":
+    import argparse
+    parser = argparse.ArgumentParser(description="Batch-process MKV files with resumable video encoding, audio downmixing, per-file logging, and optional autocrop.")
+    parser.add_argument("--no-downmix", action="store_true", help="Preserve original audio channel layout.")
+    parser.add_argument("--autocrop", action="store_true", help="Automatically detect and crop black bars from video using cropdetect.")
+    parser.add_argument("--grain", type=int, default=8, help="Set the photon-noise value for grain synthesis (default: 8).")
+    parser.add_argument("--crf", type=int, default=28, help="Set the constant quality level (cq-level) for video encoding (default: 28).")
+    args = parser.parse_args()
+    main(no_downmix=args.no_downmix, autocrop=args.autocrop, grain=args.grain, crf=args.crf)

parameters.md

@@ -0,0 +1,134 @@
+# Encoding Configuration Parameters
+
+This document details the configuration parameters used across the AomEnc and SVT-AV1 encoding scripts.
+
+## Audio Demuxing & Downmixing
+
+The audio processing extracts streams using `ffmpeg` and automatically downmixes surround layouts to stereo if requested.
+
+### Downmixing Parameters
+- **5.1 Channel Layouts (6 channels)**
+  ```text
+  -af "pan=stereo|c0=c2+0.30*c0+0.30*c4|c1=c2+0.30*c1+0.30*c5"
+  ```
+
+- **7.1 Channel Layouts (8 channels)**
+  ```text
+  -af "pan=stereo|c0=c2+0.30*c0+0.30*c4+0.30*c6|c1=c2+0.30*c1+0.30*c5+0.30*c7"
+  ```
+
+### Non-Downmixed Encoding Bitrates (Opus)
+When preserving the original channel layout (no downmixing) or if the source is already stereo/mono, audio is encoded with the following bitrates based on channel count:
+
+- **Mono (1 channel)**: `64k`
+- **Stereo (2 channels)**: `128k`
+- **5.1 Surround (6 channels)**: `256k`
+- **7.1 Surround (8 channels)**: `384k`
+- **Other/Uncommon Layouts**: `192k` (fallback default)
+
+## VFR to CFR Conversion
+
+To handle Variable Frame Rate (VFR) sources reliably on UTVideo intermediate generation, `HandBrakeCLI` is used to convert them to Constant Frame Rate (CFR) before processing.
+
+The exact HandBrakeCLI arguments used:
+```text
+HandBrakeCLI \
+  --input <source_file> \
+  --output <intermediate_cfr_file> \
+  --cfr \
+  --rate <target_cfr_fps> \
+  --encoder x264_10bit \
+  --quality 0 \
+  --encoder-preset superfast \
+  --encoder-tune fastdecode \
+  --audio none \
+  --subtitle none \
+  --crop-mode none
+```
+
+## Encoder-Specific Parameters
+
+### AomEnc (aom-psy101)
+> **Special Version Repository**: [https://gitlab.com/damian101/aom-psy101](https://gitlab.com/damian101/aom-psy101)
+
+Parameters parsed to the `aom` encoder:
+```text
+--bit-depth=10 \
+--cpu-used=2 \
+--end-usage=q \
+--cq-level=<crf_value> \
+--min-q=6 \
+--threads=2 \
+--tune-content=psy \
+--frame-parallel=1 \
+--tile-columns=1 \
+--gf-max-pyr-height=4 \
+--deltaq-mode=2 \
+--enable-keyframe-filtering=0 \
+--disable-kf \
+--enable-fwd-kf=0 \
+--kf-max-dist=9999 \
+--sb-size=dynamic \
+--enable-chroma-deltaq=1 \
+--enable-qm=1 \
+--color-primaries=bt709 \
+--transfer-characteristics=bt709 \
+--matrix-coefficients=bt709
+```
+*(Note: `--cq-level` dynamically defaults to `28` but can be overwritten when executing the script via the `--crf` argument).*
+
+### SVT-AV1 (SVT-AV1-Essential)
+> **Special Version Repository**: [https://github.com/nekotrix/SVT-AV1-Essential/](https://github.com/nekotrix/SVT-AV1-Essential/)
+
+Parameters initialized for the `svt-av1` encoder:
+```text
+--speed slower \
+--quality medium \
+--film-grain <grain_value> \
+--color-primaries 1 \
+--transfer-characteristics 1 \
+--matrix-coefficients 1 \
+--scd 0 \
+--keyint 0 \
+--lp 2 \
+--auto-tiling 1 \
+--tune 1 \
+--progress 2
+```
+*(Note: Parameters such as `--speed`, `--quality`, and `--film-grain` can be overridden when executing the script).*
+
+## av1an Initiation Commands
+
+### AomEnc
+Arguments used to start `av1an` using the AomEnc encoder:
+```text
+av1an -i <vpy_script> -o <encoded_mkv> -n \
+  -e aom \
+  --photon-noise <grain> \
+  --resume \
+  --sc-pix-format yuv420p \
+  -c mkvmerge \
+  --set-thread-affinity 2 \
+  --pix-format yuv420p10le \
+  --force \
+  --no-defaults \
+  -w <calculated_workers> \
+  --passes 2 \
+  -v "<aom_encoder_parameters_above>"
+```
+
+### SVT-AV1
+Arguments used to start `av1an` using the SVT-AV1 encoder:
+```text
+av1an -i <vpy_script> -o <encoded_mkv> -n \
+  -e svt-av1 \
+  --resume \
+  --sc-pix-format yuv420p \
+  -c mkvmerge \
+  --set-thread-affinity 2 \
+  --pix-format yuv420p10le \
+  --force \
+  --no-defaults \
+  -w <calculated_workers> \
+  -v "<svt_av1_encoder_parameters_above>"
+```

svt_opus_encoder.py

@@ -0,0 +1,773 @@
+#!/usr/bin/env python3
+import os
+import sys
+import subprocess
+import shutil
+import tempfile
+import json
+import re # Added for VFR frame rate parsing
+from datetime import datetime
+from pathlib import Path
+
+REQUIRED_TOOLS = [
+    "ffmpeg", "ffprobe", "mkvmerge", "mkvpropedit",
+    "opusenc", "mediainfo", "av1an", "HandBrakeCLI", "ffmsindex" # Added HandBrakeCLI and ffmsindex
+]
+DIR_COMPLETED = Path("completed")
+DIR_ORIGINAL = Path("original")
+DIR_CONV_LOGS = Path("conv_logs") # Directory for conversion logs
+
+REMUX_CODECS = {"aac", "opus"}  # Using a set for efficient lookups
+
+SVT_AV1_PARAMS = {
+    "speed": "slower",  # "slower", "slow", "medium", "fast", "faster"
+    "quality": "medium",  # "higher", "high", "medium", "low", "lower"
+    "film-grain": 6,
+    "color-primaries": 1,
+    "transfer-characteristics": 1,
+    "matrix-coefficients": 1,
+    "scd": 0,  # Scene change detection OFF for Av1an use
+    "keyint": 0,  # Keyframe interval, 0 disables automatic keyframes placement at a constant interval
+    "lp": 2, # Level of parallelism
+    "auto-tiling": 1,  # Auto tiling ON
+    "tune": 1,  # 0 = VQ, 1 = PSNR, 2 = SSIM
+    "progress": 2,  # Detailed progress output
+}
+
+def check_tools():
+    for tool in REQUIRED_TOOLS:
+        if shutil.which(tool) is None:
+            print(f"Required tool '{tool}' not found in PATH.")
+            sys.exit(1)
+
+def run_cmd(cmd, capture_output=False, check=True):
+    if capture_output:
+        result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, check=check, text=True)
+        return result.stdout
+    else:
+        subprocess.run(cmd, check=check)
+
+def convert_audio_track(index, ch, lang, audio_temp_dir, source_file, should_downmix):
+    audio_temp_path = Path(audio_temp_dir)
+    temp_extracted = audio_temp_path / f"track_{index}_extracted.flac"
+    temp_normalized = audio_temp_path / f"track_{index}_normalized.flac"
+    final_opus = audio_temp_path / f"track_{index}_final.opus"
+
+    print(f"    - Extracting Audio Track #{index} to FLAC...")
+    ffmpeg_args = [
+        "ffmpeg", "-v", "quiet", "-stats", "-y", "-i", str(source_file), "-map", f"0:{index}", "-map_metadata", "-1"
+    ]
+    if should_downmix and ch >= 6:
+        if ch == 6:
+            ffmpeg_args += ["-af", "pan=stereo|c0=c2+0.30*c0+0.30*c4|c1=c2+0.30*c1+0.30*c5"]
+        elif ch == 8:
+            ffmpeg_args += ["-af", "pan=stereo|c0=c2+0.30*c0+0.30*c4+0.30*c6|c1=c2+0.30*c1+0.30*c5+0.30*c7"]
+        else: # Other multi-channel (e.g. 7ch, 10ch)
+            ffmpeg_args += ["-ac", "2"]
+    ffmpeg_args += ["-c:a", "flac", str(temp_extracted)]
+    run_cmd(ffmpeg_args)
+
+    print(f"    - Normalizing Audio Track #{index} with ffmpeg (loudnorm 2-pass)...")
+    # First pass: Analyze the audio to get loudnorm stats
+    # The stats are printed to stderr, so we must use subprocess.run directly to capture it.
+    print("      - Pass 1: Analyzing...")
+    result = subprocess.run(
+        ["ffmpeg", "-v", "info", "-i", str(temp_extracted), "-af", "loudnorm=I=-23:LRA=7:tp=-1:print_format=json", "-f", "null", "-"],
+        capture_output=True, text=True, check=True)
+    
+    # Find the start of the JSON block in stderr and parse it.
+    # This is more robust than slicing the last N lines.
+    # We find the start and end of the JSON block to avoid parsing extra data.
+    stderr_output = result.stderr
+    json_start_index = stderr_output.find('{')
+    if json_start_index == -1:
+        raise ValueError("Could not find start of JSON block in ffmpeg output for loudnorm analysis.")
+
+    brace_level = 0
+    json_end_index = -1
+    for i, char in enumerate(stderr_output[json_start_index:]):
+        if char == '{':
+            brace_level += 1
+        elif char == '}':
+            brace_level -= 1
+            if brace_level == 0:
+                json_end_index = json_start_index + i + 1
+                break
+    
+    stats = json.loads(stderr_output[json_start_index:json_end_index])
+
+    # Second pass: Apply the normalization using the stats from the first pass
+    print("      - Pass 2: Applying normalization...")
+    run_cmd([
+        "ffmpeg", "-v", "quiet", "-stats", "-y", "-i", str(temp_extracted), "-af",
+        f"loudnorm=I=-23:LRA=7:tp=-1:measured_i={stats['input_i']}:measured_lra={stats['input_lra']}:measured_tp={stats['input_tp']}:measured_thresh={stats['input_thresh']}:offset={stats['target_offset']}",
+        "-c:a", "flac", str(temp_normalized)
+    ])
+
+    # Set bitrate based on the final channel count of the Opus file.
+    # If we are downmixing, the result is stereo.
+    # If not, the result has the original channel count.
+    is_being_downmixed = should_downmix and ch >= 6
+
+    if is_being_downmixed:
+        # Downmixing from 5.1 or 7.1 results in a stereo track.
+        bitrate = "128k"
+    else:
+        # Not downmixing (or source is already stereo or less).
+        # Base bitrate on the source channel count.
+        if ch == 1:      # Mono
+            bitrate = "64k"
+        elif ch == 2:    # Stereo
+            bitrate = "128k"
+        elif ch == 6:    # 5.1 Surround
+            bitrate = "256k"
+        elif ch == 8:    # 7.1 Surround
+            bitrate = "384k"
+        else:            # Other layouts
+            bitrate = "192k" # A sensible default for other/uncommon layouts.
+
+    print(f"    - Encoding Audio Track #{index} to Opus at {bitrate}...")
+    run_cmd([
+        "opusenc", "--vbr", "--bitrate", bitrate, str(temp_normalized), str(final_opus)
+    ])
+    return final_opus
+
+def convert_video(source_file_base, source_file_full, is_vfr, target_cfr_fps_for_handbrake, autocrop_filter=None):
+    print("  --- Starting Video Processing ---")
+    # source_file_base is file_path.stem (e.g., "my.anime.episode.01")
+    vpy_file = Path(f"{source_file_base}.vpy")
+    ut_video_file = Path(f"{source_file_base}.ut.mkv")
+    encoded_video_file = Path(f"temp-{source_file_base}.mkv")
+    handbrake_cfr_intermediate_file = None # To store path of HandBrake output if created
+
+    current_input_for_utvideo = Path(source_file_full)
+
+    if is_vfr and target_cfr_fps_for_handbrake:
+        print(f"    - Source is VFR. Converting to CFR ({target_cfr_fps_for_handbrake}) with HandBrakeCLI...")
+        handbrake_cfr_intermediate_file = Path(f"{source_file_base}.cfr_temp.mkv")
+        handbrake_args = [
+            "HandBrakeCLI", 
+            "--input", str(source_file_full), 
+            "--output", str(handbrake_cfr_intermediate_file),
+            "--cfr", 
+            "--rate", str(target_cfr_fps_for_handbrake),
+            "--encoder", "x264_10bit", # Changed to x264_10bit for 10-bit CFR intermediate
+            "--quality", "0", # CRF 0 for x264 is often considered visually lossless, or near-lossless
+            "--encoder-preset", "superfast", # Use a fast preset for quicker processing
+            "--encoder-tune", "fastdecode", # Added tune for faster decoding
+            "--audio", "none", 
+            "--subtitle", "none",
+            "--crop-mode", "none" # Disable auto-cropping
+        ]
+        print(f"    - Running HandBrakeCLI: {' '.join(handbrake_args)}")
+        try:
+            run_cmd(handbrake_args)
+            if handbrake_cfr_intermediate_file.exists() and handbrake_cfr_intermediate_file.stat().st_size > 0:
+                print(f"    - HandBrake VFR to CFR conversion successful: {handbrake_cfr_intermediate_file}")
+                current_input_for_utvideo = handbrake_cfr_intermediate_file
+            else:
+                print(f"    - Warning: HandBrakeCLI VFR-to-CFR conversion failed or produced an empty file. Proceeding with original source for UTVideo.")
+                handbrake_cfr_intermediate_file = None # Ensure it's None if failed
+        except subprocess.CalledProcessError as e:
+            print(f"    - Error during HandBrakeCLI execution: {e}")
+            print(f"    - Proceeding with original source for UTVideo.")
+            handbrake_cfr_intermediate_file = None # Ensure it's None if failed
+
+
+    print("    - Creating UTVideo intermediate file (overwriting if exists)...")
+    # Check if source is already UTVideo
+    ffprobe_cmd = [
+        "ffprobe", "-v", "error", "-select_streams", "v:0",
+        "-show_entries", "stream=codec_name", "-of", "default=noprint_wrappers=1:nokey=1",
+        str(current_input_for_utvideo) # Use current input, which might be HandBrake output
+    ]
+    source_codec = run_cmd(ffprobe_cmd, capture_output=True, check=True).strip()
+
+    video_codec_args = ["-c:v", "utvideo"]
+    if source_codec == "utvideo" and current_input_for_utvideo == Path(source_file_full): # Only copy if original was UTVideo
+        print("    - Source is already UTVideo. Copying video stream...")
+        video_codec_args = ["-c:v", "copy"]
+
+    ffmpeg_args = [
+        "ffmpeg", "-hide_banner", "-v", "quiet", "-stats", "-y", "-i", str(current_input_for_utvideo),
+        "-map", "0:v:0", "-map_metadata", "-1", "-map_chapters", "-1", "-an", "-sn", "-dn",
+    ]
+    if autocrop_filter:
+        ffmpeg_args += ["-vf", autocrop_filter]
+    ffmpeg_args += video_codec_args + [str(ut_video_file)]
+    run_cmd(ffmpeg_args)
+
+    print("    - Indexing UTVideo file with ffmsindex for VapourSynth...")
+    ffmsindex_args = ["ffmsindex", "-f", str(ut_video_file)]
+    run_cmd(ffmsindex_args)
+
+    ut_video_full_path = os.path.abspath(ut_video_file)
+    vpy_script_content = f"""import vapoursynth as vs
+core = vs.core
+core.num_threads = 4
+clip = core.ffms2.Source(source=r'''{ut_video_full_path}''')
+clip = core.resize.Point(clip, format=vs.YUV420P10, matrix_in_s="709") # type: ignore
+clip.set_output()
+"""
+    with vpy_file.open("w", encoding="utf-8") as f:
+        f.write(vpy_script_content)
+
+    print("    - Starting AV1 encode with av1an (this will take a long time)...")
+    total_cores = os.cpu_count() or 4 # Fallback if cpu_count is None
+    workers = max(1, (total_cores // 2) - 1) # Half the cores minus one, with a minimum of 1 worker.
+    print(f"    - Using {workers} workers for av1an (Total Cores: {total_cores}, Logic: (Cores/2)-1).")
+
+    # Create the parameter string for av1an's -v option, which expects a single string.
+    av1an_video_params_str = " ".join([f"--{key} {value}" for key, value in SVT_AV1_PARAMS.items()])
+    print(f"    - Using SVT-AV1 parameters: {av1an_video_params_str}")
+
+    av1an_enc_args = [
+        "av1an", "-i", str(vpy_file), "-o", str(encoded_video_file), "-n",
+        "-e", "svt-av1", "--resume", "--sc-pix-format", "yuv420p", "-c", "mkvmerge",
+        "--set-thread-affinity", "2", "--pix-format", "yuv420p10le", "--force", "--no-defaults",
+        "-w", str(workers),
+        "-v", av1an_video_params_str
+    ]
+    run_cmd(av1an_enc_args)
+    print("  --- Finished Video Processing ---")
+    return encoded_video_file, handbrake_cfr_intermediate_file
+
+def is_ffmpeg_decodable(file_path):
+    """Quickly check if ffmpeg can decode the input file."""
+    try:
+        # Try to decode a short segment of the first audio stream
+        subprocess.run([
+            "ffmpeg", "-v", "error", "-i", str(file_path), "-map", "0:a:0", "-t", "1", "-f", "null", "-"
+        ], check=True)
+        return True
+    except subprocess.CalledProcessError:
+        return False
+
+# --- CROPDETECT LOGIC FROM cropdetect.py ---
+import argparse as _argparse_cropdetect
+import multiprocessing as _multiprocessing_cropdetect
+from collections import Counter as _Counter_cropdetect
+
+COLOR_GREEN = "\033[92m"
+COLOR_RED = "\033[91m"
+COLOR_YELLOW = "\033[93m"
+COLOR_RESET = "\033[0m"
+
+KNOWN_ASPECT_RATIOS = [
+    {"name": "HDTV (16:9)", "ratio": 16/9},
+    {"name": "Widescreen (Scope)", "ratio": 2.39},
+    {"name": "Widescreen (Flat)", "ratio": 1.85},
+    {"name": "IMAX Digital (1.90:1)", "ratio": 1.90},
+    {"name": "Fullscreen (4:3)", "ratio": 4/3},
+    {"name": "IMAX 70mm (1.43:1)", "ratio": 1.43},
+]
+
+def _check_prerequisites_cropdetect():
+    for tool in ['ffmpeg', 'ffprobe']:
+        if not shutil.which(tool):
+            print(f"Error: '{tool}' command not found. Is it installed and in your PATH?")
+            return False
+    return True
+
+def _analyze_segment_cropdetect(task_args):
+    seek_time, input_file, width, height = task_args
+    ffmpeg_args = [
+        'ffmpeg', '-hide_banner',
+        '-ss', str(seek_time),
+        '-i', input_file, '-t', '1', '-vf', 'cropdetect',
+        '-f', 'null', '-'
+    ]
+    result = subprocess.run(ffmpeg_args, capture_output=True, text=True, encoding='utf-8')
+    if result.returncode != 0:
+        return []
+    crop_detections = re.findall(r'crop=(\d+):(\d+):(\d+):(\d+)', result.stderr)
+    significant_crops = []
+    for w_str, h_str, x_str, y_str in crop_detections:
+        w, h, x, y = map(int, [w_str, h_str, x_str, y_str])
+        significant_crops.append((f"crop={w}:{h}:{x}:{y}", seek_time))
+    return significant_crops
+
+def _snap_to_known_ar_cropdetect(w, h, x, y, video_w, video_h, tolerance=0.03):
+    if h == 0: return f"crop={w}:{h}:{x}:{y}", None
+    detected_ratio = w / h
+    best_match = None
+    smallest_diff = float('inf')
+    for ar in KNOWN_ASPECT_RATIOS:
+        diff = abs(detected_ratio - ar['ratio'])
+        if diff < smallest_diff:
+            smallest_diff = diff
+            best_match = ar
+    if not best_match or (smallest_diff / best_match['ratio']) >= tolerance:
+        return f"crop={w}:{h}:{x}:{y}", None
+    if abs(w - video_w) < 16:
+        new_h = round(video_w / best_match['ratio'])
+        if new_h % 8 != 0:
+            new_h = new_h + (8 - (new_h % 8))
+        new_h = min(new_h, video_h)
+        new_y = round((video_h - new_h) / 2)
+        if new_y % 2 != 0:
+            new_y -= 1
+        new_y = max(0, new_y)
+        return f"crop={video_w}:{new_h}:0:{new_y}", best_match['name']
+    if abs(h - video_h) < 16:
+        new_w = round(video_h * best_match['ratio'])
+        if new_w % 8 != 0:
+            new_w = new_w + (8 - (new_w % 8))
+        new_w = min(new_w, video_w)
+        new_x = round((video_w - new_w) / 2)
+        if new_x % 2 != 0:
+            new_x -= 1
+        new_x = max(0, new_x)
+        return f"crop={new_w}:{video_h}:{new_x}:0", best_match['name']
+    return f"crop={w}:{h}:{x}:{y}", None
+
+def _cluster_crop_values_cropdetect(crop_counts, tolerance=8):
+    clusters = []
+    temp_counts = crop_counts.copy()
+    while temp_counts:
+        center_str, _ = temp_counts.most_common(1)[0]
+        try:
+            _, values = center_str.split('=');
+            cw, ch, cx, cy = map(int, values.split(':'))
+        except (ValueError, IndexError):
+            del temp_counts[center_str]
+            continue
+        cluster_total_count = 0
+        crops_to_remove = []
+        for crop_str, count in temp_counts.items():
+            try:
+                _, values = crop_str.split('=');
+                w, h, x, y = map(int, values.split(':'))
+                if abs(x - cx) <= tolerance and abs(y - cy) <= tolerance:
+                    cluster_total_count += count
+                    crops_to_remove.append(crop_str)
+            except (ValueError, IndexError):
+                continue
+        if cluster_total_count > 0:
+            clusters.append({'center': center_str, 'count': cluster_total_count})
+        for crop_str in crops_to_remove:
+            del temp_counts[crop_str]
+    clusters.sort(key=lambda c: c['count'], reverse=True)
+    return clusters
+
+def _parse_crop_string_cropdetect(crop_str):
+    try:
+        _, values = crop_str.split('=');
+        w, h, x, y = map(int, values.split(':'))
+        return {'w': w, 'h': h, 'x': x, 'y': y}
+    except (ValueError, IndexError):
+        return None
+
+def _calculate_bounding_box_cropdetect(crop_keys):
+    min_x = min_w = min_y = min_h = float('inf')
+    max_x = max_w = max_y = max_h = float('-inf')
+    for key in crop_keys:
+        parsed = _parse_crop_string_cropdetect(key)
+        if not parsed:
+            continue
+        w, h, x, y = parsed['w'], parsed['h'], parsed['x'], parsed['y']
+        min_x = min(min_x, x)
+        min_y = min(min_y, y)
+        max_x = max(max_x, x + w)
+        max_y = max(max_y, y + h)
+        min_w = min(min_w, w)
+        min_h = min(min_h, h)
+        max_w = max(max_w, w)
+        max_h = max(max_h, h)
+    if (max_x - min_x) <= 2 and (max_y - min_y) <= 2:
+        return None
+    bounding_crop = f"crop={max_x - min_x}:{max_y - min_y}:{min_x}:{min_y}"
+    return bounding_crop
+
+def _analyze_video_cropdetect(input_file, duration, width, height, num_workers, significant_crop_threshold, min_crop, debug=False):
+    num_tasks = num_workers * 4
+    segment_duration = max(1, duration // num_tasks)
+    tasks = [(i * segment_duration, input_file, width, height) for i in range(num_tasks)]
+    crop_results = []
+    with _multiprocessing_cropdetect.Pool(processes=num_workers) as pool:
+        results_iterator = pool.imap_unordered(_analyze_segment_cropdetect, tasks)
+        for result in results_iterator:
+            crop_results.append(result)
+    all_crops_with_ts = [crop for sublist in crop_results for crop in sublist]
+    all_crop_strings = [item[0] for item in all_crops_with_ts]
+    if not all_crop_strings:
+        return None
+    crop_counts = _Counter_cropdetect(all_crop_strings)
+    clusters = _cluster_crop_values_cropdetect(crop_counts)
+    total_detections = sum(c['count'] for c in clusters)
+    significant_clusters = []
+    for cluster in clusters:
+        percentage = (cluster['count'] / total_detections) * 100
+        if percentage >= significant_crop_threshold:
+            significant_clusters.append(cluster)
+    for cluster in significant_clusters:
+        parsed_crop = _parse_crop_string_cropdetect(cluster['center'])
+        if parsed_crop:
+            _, ar_label = _snap_to_known_ar_cropdetect(
+                parsed_crop['w'], parsed_crop['h'], parsed_crop['x'], parsed_crop['y'], width, height
+            )
+            cluster['ar_label'] = ar_label
+        else:
+            cluster['ar_label'] = None
+    if not significant_clusters:
+        return None
+    elif len(significant_clusters) == 1:
+        dominant_cluster = significant_clusters[0]
+        parsed_crop = _parse_crop_string_cropdetect(dominant_cluster['center'])
+        snapped_crop, ar_label = _snap_to_known_ar_cropdetect(
+            parsed_crop['w'], parsed_crop['h'], parsed_crop['x'], parsed_crop['y'], width, height
+        )
+        parsed_snapped = _parse_crop_string_cropdetect(snapped_crop)
+        if parsed_snapped and parsed_snapped['w'] == width and parsed_snapped['h'] == height:
+            return None
+        else:
+            return snapped_crop
+    else:
+        crop_keys = [c['center'] for c in significant_clusters]
+        bounding_box_crop = _calculate_bounding_box_cropdetect(crop_keys)
+        if bounding_box_crop:
+            parsed_bb = _parse_crop_string_cropdetect(bounding_box_crop)
+            snapped_crop, ar_label = _snap_to_known_ar_cropdetect(
+                parsed_bb['w'], parsed_bb['h'], parsed_bb['x'], parsed_bb['y'], width, height
+            )
+            parsed_snapped = _parse_crop_string_cropdetect(snapped_crop)
+            if parsed_snapped and parsed_snapped['w'] == width and parsed_snapped['h'] == height:
+                return None
+            else:
+                return snapped_crop
+        else:
+            return None
+
+def detect_autocrop_filter(input_file, significant_crop_threshold=5.0, min_crop=10, debug=False):
+    if not _check_prerequisites_cropdetect():
+        return None
+    try:
+        probe_duration_args = [
+            'ffprobe', '-v', 'error', '-show_entries', 'format=duration', '-of', 'default=noprint_wrappers=1:nokey=1',
+            input_file
+        ]
+        duration_str = subprocess.check_output(probe_duration_args, stderr=subprocess.STDOUT, text=True)
+        duration = int(float(duration_str))
+        probe_res_args = [
+            'ffprobe', '-v', 'error',
+            '-select_streams', 'v',
+            '-show_entries', 'stream=width,height,disposition',
+            '-of', 'json',
+            input_file
+        ]
+        probe_output = subprocess.check_output(probe_res_args, stderr=subprocess.STDOUT, text=True)
+        streams_data = json.loads(probe_output)
+        video_stream = None
+        for stream in streams_data.get('streams', []):
+            if stream.get('disposition', {}).get('attached_pic', 0) == 0:
+                video_stream = stream
+                break
+        if not video_stream or 'width' not in video_stream or 'height' not in video_stream:
+            return None
+        width = int(video_stream['width'])
+        height = int(video_stream['height'])
+    except Exception:
+        return None
+    return _analyze_video_cropdetect(input_file, duration, width, height, max(1, os.cpu_count() // 2), significant_crop_threshold, min_crop, debug)
+
+def main(no_downmix=False, autocrop=False, speed=None, quality=None, grain=None):
+    check_tools()
+
+    # Override default SVT-AV1 params if provided via command line
+    if speed:
+        SVT_AV1_PARAMS["speed"] = speed
+    if quality:
+        SVT_AV1_PARAMS["quality"] = quality
+    if grain is not None:
+        SVT_AV1_PARAMS["film-grain"] = grain
+
+    current_dir = Path(".")
+    files_to_process = sorted(
+        f for f in current_dir.glob("*.mkv")
+        if not (f.name.endswith(".ut.mkv") or f.name.startswith("temp-") or f.name.startswith("output-") or f.name.endswith(".cfr_temp.mkv"))
+    )
+    if not files_to_process:
+        print("No MKV files found to process. Exiting.")
+        return
+    DIR_COMPLETED.mkdir(exist_ok=True, parents=True)
+    DIR_ORIGINAL.mkdir(exist_ok=True, parents=True)
+    DIR_CONV_LOGS.mkdir(exist_ok=True, parents=True)
+    while True:
+        files_to_process = sorted(
+            f for f in current_dir.glob("*.mkv")
+            if not (f.name.endswith(".ut.mkv") or f.name.startswith("temp-") or f.name.startswith("output-") or f.name.endswith(".cfr_temp.mkv"))
+        )
+        if not files_to_process:
+            print("No more .mkv files found to process in the current directory. The script will now exit.")
+            break
+        file_path = files_to_process[0]
+        if not is_ffmpeg_decodable(file_path):
+            print(f"ERROR: ffmpeg cannot decode '{file_path.name}'. Skipping this file.", file=sys.stderr)
+            shutil.move(str(file_path), DIR_ORIGINAL / file_path.name)
+            continue
+        print("-" * shutil.get_terminal_size(fallback=(80, 24)).columns)
+        log_file_name = f"{file_path.stem}.log"
+        log_file_path = DIR_CONV_LOGS / log_file_name
+        original_stdout_console = sys.stdout
+        original_stderr_console = sys.stderr
+        print(f"Processing: {file_path.name}", file=original_stdout_console)
+        print(f"Logging output to: {log_file_path}", file=original_stdout_console)
+        log_file_handle = None
+        processing_error_occurred = False
+        date_for_runtime_calc = datetime.now()
+        try:
+            log_file_handle = open(log_file_path, 'w', encoding='utf-8')
+            sys.stdout = log_file_handle
+            sys.stderr = log_file_handle
+            print(f"STARTING LOG FOR: {file_path.name}")
+            print(f"Processing started at: {date_for_runtime_calc}")
+            print(f"Full input file path: {file_path.resolve()}")
+            print("-" * shutil.get_terminal_size(fallback=(80, 24)).columns)
+            input_file_abs = file_path.resolve()
+            intermediate_output_file = current_dir / f"output-{file_path.name}"
+            audio_temp_dir = None
+            handbrake_intermediate_for_cleanup = None
+            try:
+                audio_temp_dir = tempfile.mkdtemp(prefix="anime_audio_")
+                print(f"Audio temporary directory created at: {audio_temp_dir}")
+                print(f"Analyzing file: {input_file_abs}")
+                ffprobe_info_json = run_cmd([
+                    "ffprobe", "-v", "quiet", "-print_format", "json", "-show_streams", "-show_format", str(input_file_abs)
+                ], capture_output=True)
+                ffprobe_info = json.loads(ffprobe_info_json)
+                mkvmerge_info_json = run_cmd([
+                    "mkvmerge", "-J", str(input_file_abs)
+                ], capture_output=True)
+                mkv_info = json.loads(mkvmerge_info_json)
+                mediainfo_json = run_cmd([
+                    "mediainfo", "--Output=JSON", "-f", str(input_file_abs)
+                ], capture_output=True)
+                media_info = json.loads(mediainfo_json)
+                is_vfr = False
+                target_cfr_fps_for_handbrake = None
+                video_track_info = None
+                if media_info.get("media") and media_info["media"].get("track"):
+                    for track in media_info["media"]["track"]:
+                        if track.get("@type") == "Video":
+                            video_track_info = track
+                            break
+                if video_track_info:
+                    frame_rate_mode = video_track_info.get("FrameRate_Mode")
+                    if frame_rate_mode and frame_rate_mode.upper() in ["VFR", "VARIABLE"]:
+                        is_vfr = True
+                        print(f"    - Detected VFR based on MediaInfo FrameRate_Mode: {frame_rate_mode}")
+                        original_fps_str = video_track_info.get("FrameRate_Original_String")
+                        if original_fps_str:
+                            match = re.search(r'\((\d+/\d+)\)', original_fps_str)
+                            if match:
+                                target_cfr_fps_for_handbrake = match.group(1)
+                            else:
+                                target_cfr_fps_for_handbrake = video_track_info.get("FrameRate_Original")
+                        if not target_cfr_fps_for_handbrake:
+                            target_cfr_fps_for_handbrake = video_track_info.get("FrameRate_Original")
+                        if not target_cfr_fps_for_handbrake:
+                            target_cfr_fps_for_handbrake = video_track_info.get("FrameRate")
+                            if target_cfr_fps_for_handbrake:
+                                print(f"    - Using MediaInfo FrameRate ({target_cfr_fps_for_handbrake}) as fallback for HandBrake target FPS.")
+                        if target_cfr_fps_for_handbrake:
+                            print(f"    - Target CFR for HandBrake: {target_cfr_fps_for_handbrake}")
+                            if isinstance(target_cfr_fps_for_handbrake, str) and "/" in target_cfr_fps_for_handbrake:
+                                try:
+                                    num, den = map(float, target_cfr_fps_for_handbrake.split('/'))
+                                    target_cfr_fps_for_handbrake = f"{num / den:.3f}"
+                                    print(f"    - Converted fractional FPS to decimal for HandBrake: {target_cfr_fps_for_handbrake}")
+                                except ValueError:
+                                    print(f"    - Warning: Could not parse fractional FPS '{target_cfr_fps_for_handbrake}'. HandBrakeCLI might fail.")
+                                    is_vfr = False
+                        else:
+                            print("    - Warning: VFR detected, but could not determine target CFR from MediaInfo. Will attempt standard UTVideo conversion without HandBrake.")
+                            is_vfr = False
+                    else:
+                        print(f"    - Video appears to be CFR or FrameRate_Mode not specified as VFR/Variable by MediaInfo.")
+                autocrop_filter = None
+                if autocrop:
+                    print("--- Running autocrop detection ---")
+                    autocrop_filter = detect_autocrop_filter(str(input_file_abs))
+                    if autocrop_filter:
+                        print(f"    - Autocrop filter detected: {autocrop_filter}")
+                    else:
+                        print("    - No crop needed or detected.")
+                encoded_video_file, handbrake_intermediate_for_cleanup = convert_video(
+                    file_path.stem, str(input_file_abs), is_vfr, target_cfr_fps_for_handbrake, autocrop_filter=autocrop_filter
+                )
+
+                print("--- Starting Audio Processing ---")
+                processed_audio_files = []
+                audio_tracks_to_remux = []
+                audio_streams = [s for s in ffprobe_info.get("streams", []) if s.get("codec_type") == "audio"]
+
+                # Build mkvmerge track mapping by track ID
+                mkv_audio_tracks = {t["id"]: t for t in mkv_info.get("tracks", []) if t.get("type") == "audio"}
+
+                # Build mediainfo track mapping by StreamOrder
+                media_tracks_data = media_info.get("media", {}).get("track", [])
+                mediainfo_audio_tracks = {int(t.get("StreamOrder", -1)): t for t in media_tracks_data if t.get("@type") == "Audio"}
+
+                for stream in audio_streams:
+                    stream_index = stream["index"]
+                    codec = stream.get("codec_name")
+                    channels = stream.get("channels", 2)
+                    language = stream.get("tags", {}).get("language", "und")
+
+                    # Find mkvmerge track by matching ffprobe stream index to mkvmerge track's 'properties'->'stream_id'
+                    mkv_track = None
+                    for t in mkv_info.get("tracks", []):
+                        if t.get("type") == "audio" and t.get("properties", {}).get("stream_id") == stream_index:
+                            mkv_track = t
+                            break
+                    if not mkv_track:
+                        # Fallback: try by position
+                        mkv_track = mkv_info.get("tracks", [])[stream_index] if stream_index < len(mkv_info.get("tracks", [])) else {}
+
+                    track_id = mkv_track.get("id", -1)
+                    track_title = mkv_track.get("properties", {}).get("track_name", "")
+
+                    # Find mediainfo track by StreamOrder
+                    audio_track_info = mediainfo_audio_tracks.get(stream_index)
+                    track_delay = 0
+                    delay_raw = audio_track_info.get("Video_Delay") if audio_track_info else None
+                    if delay_raw is not None:
+                        try:
+                            delay_val = float(delay_raw)
+                            # If the value is a float < 1, it's seconds, so convert to ms.
+                            if delay_val < 1:
+                                track_delay = int(round(delay_val * 1000))
+                            else:
+                                track_delay = int(round(delay_val))
+                        except Exception:
+                            track_delay = 0
+
+                    print(f"Processing Audio Stream #{stream_index} (TID: {track_id}, Codec: {codec}, Channels: {channels})")
+                    if codec in REMUX_CODECS:
+                        audio_tracks_to_remux.append(str(track_id))
+                    else:
+                        # Convert any codec that is not in REMUX_CODECS
+                        opus_file = convert_audio_track(
+                            stream_index, channels, language, audio_temp_dir, str(input_file_abs), not no_downmix
+                        )
+                        processed_audio_files.append({
+                            "Path": opus_file,
+                            "Language": language,
+                            "Title": track_title,
+                            "Delay": track_delay
+                        })
+
+                print("--- Finished Audio Processing ---")
+
+                # Final mux
+                print("Assembling final file with mkvmerge...")
+                mkvmerge_args = ["mkvmerge", "-o", str(intermediate_output_file), str(encoded_video_file)]
+                for file_info in processed_audio_files:
+                    sync_switch = ["--sync", f"0:{file_info['Delay']}"] if file_info["Delay"] else []
+                    mkvmerge_args += [
+                        "--language", f"0:{file_info['Language']}",
+                        "--track-name", f"0:{file_info['Title']}"
+                    ] + sync_switch + [str(file_info["Path"])]
+
+                source_copy_args = ["--no-video"]
+                if audio_tracks_to_remux:
+                    source_copy_args += ["--audio-tracks", ",".join(audio_tracks_to_remux)]
+                else:
+                    source_copy_args += ["--no-audio"]
+                mkvmerge_args += source_copy_args + [str(input_file_abs)]
+                run_cmd(mkvmerge_args)
+
+                # Move files
+                print("Moving files to final destinations...")
+                shutil.move(str(file_path), DIR_ORIGINAL / file_path.name)
+                shutil.move(str(intermediate_output_file), DIR_COMPLETED / file_path.name)
+
+                print("Cleaning up persistent video temporary files (after successful processing)...")
+                video_temp_files_on_success = [
+                    current_dir / f"{file_path.stem}.vpy",
+                    current_dir / f"{file_path.stem}.ut.mkv",
+                    current_dir / f"temp-{file_path.stem}.mkv", # This is encoded_video_file
+                    current_dir / f"{file_path.stem}.ut.mkv.lwi", 
+                    current_dir / f"{file_path.stem}.ut.mkv.ffindex",
+                ]
+                if handbrake_intermediate_for_cleanup and handbrake_intermediate_for_cleanup.exists():
+                    video_temp_files_on_success.append(handbrake_intermediate_for_cleanup)
+                
+                for temp_vid_file in video_temp_files_on_success:
+                    if temp_vid_file.exists():
+                        print(f"    Deleting: {temp_vid_file}")
+                        temp_vid_file.unlink(missing_ok=True)
+                    else:
+                        print(f"    Skipping (not found): {temp_vid_file}")
+
+            except Exception as e:
+                print(f"ERROR: An error occurred while processing '{file_path.name}': {e}", file=sys.stderr) # Goes to log
+                original_stderr_console.write(f"ERROR during processing of '{file_path.name}': {e}\nSee log '{log_file_path}' for details.\n")
+                processing_error_occurred = True
+            finally:
+                # This is the original 'finally' block. Its prints go to the log file.
+                print("--- Starting Universal Cleanup (for this file) ---")
+                print("  - Cleaning up disposable audio temporary directory...")
+                if audio_temp_dir and Path(audio_temp_dir).exists():
+                    shutil.rmtree(audio_temp_dir, ignore_errors=True)
+                    print(f"    - Deleted audio temp dir: {audio_temp_dir}")
+                elif audio_temp_dir: # Was created but now not found
+                    print(f"    - Audio temp dir not found or already cleaned: {audio_temp_dir}")
+                else: # Was never created
+                    print(f"    - Audio temp dir was not created.")
+                
+                print("  - Cleaning up intermediate output file (if it wasn't moved on success)...")
+                if intermediate_output_file.exists(): # Check if it still exists (e.g. error before move)
+                    if processing_error_occurred:
+                        print(f"    - WARNING: Processing error occurred. Intermediate output file '{intermediate_output_file}' is being preserved at its original path for inspection.")
+                    else:
+                        # No processing error, so it should have been moved.
+                        # If it's still here, it's unexpected but we'll clean it up.
+                        print(f"    - INFO: Intermediate output file '{intermediate_output_file}' found at original path despite no errors (expected to be moved). Cleaning up.")
+                        intermediate_output_file.unlink(missing_ok=True) # Only unlink if no error and it exists
+                        print(f"    - Deleted intermediate output file from original path: {intermediate_output_file}")
+                else:
+                    # File does not exist at original path
+                    if not processing_error_occurred:
+                        print(f"    - Intermediate output file successfully moved (not found at original path, as expected): {intermediate_output_file}")
+                    else:
+                        print(f"    - Processing error occurred, and intermediate output file '{intermediate_output_file}' not found at original path (likely not created or cleaned by another step).")
+            # --- End of original per-file processing block ---
+
+            print(f"FINISHED LOG FOR: {file_path.name}")
+            # --- End of log-specific messages ---
+
+        finally: # Outer finally for restoring stdout/stderr and closing log file
+            runtime = datetime.now() - date_for_runtime_calc
+            runtime_str = str(runtime).split('.')[0]
+            
+            # This print goes to the log file, as stdout is not yet restored.
+            print(f"\nTotal runtime for this file: {runtime_str}")
+            
+            if sys.stdout != original_stdout_console:
+                sys.stdout = original_stdout_console
+            if sys.stderr != original_stderr_console:
+                sys.stderr = original_stderr_console
+            if log_file_handle:
+                log_file_handle.close()
+            
+            # Announce to console (original stdout/stderr) that this file is done
+            if processing_error_occurred:
+                original_stderr_console.write(f"File: {file_path.name}\n")
+                original_stderr_console.write(f"Log: {log_file_path}\n")
+                original_stderr_console.write(f"Runtime: {runtime_str}\n")
+            else:
+                original_stdout_console.write(f"File: {file_path.name}\n")
+                original_stdout_console.write(f"Log: {log_file_path}\n")
+                original_stdout_console.write(f"Runtime: {runtime_str}\n")
+
+if __name__ == "__main__":
+    import argparse
+    parser = argparse.ArgumentParser(description="Batch-process MKV files with resumable video encoding, audio downmixing, per-file logging, and optional autocrop.")
+    parser.add_argument("--no-downmix", action="store_true", help="Preserve original audio channel layout.")
+    parser.add_argument("--autocrop", action="store_true", help="Automatically detect and crop black bars from video using cropdetect.")
+    parser.add_argument("--speed", type=str, help="Set the encoding speed. Possible values: slower, slow, medium, fast, faster.")
+    parser.add_argument("--quality", type=str, help="Set the encoding quality. Possible values: lowest, low, medium, high, higher.")
+    parser.add_argument("--grain", type=int, help="Set the film-grain value (number). Adjusts the film grain synthesis level.")
+    args = parser.parse_args()
+    main(no_downmix=args.no_downmix, autocrop=args.autocrop, speed=args.speed, quality=args.quality, grain=args.grain)