video_trim.py

import argparse
import os
import sys
import subprocess

# 定数
SUPPORTED_EXTENSIONS = (".mp4", ".mov")
BLACKDETECT_FILTER = 'blackdetect=d=0.0:pic_th=0.00'

def validate_directory(directory, dir_type="input"):
    """ディレクトリの存在を確認"""
    if not directory or not os.path.isdir(directory):
        print(f"Does not exist {dir_type} directory: {directory}")
        sys.exit(1)

def get_video_files(input_dir):
    """指定されたディレクトリ内の動画ファイルを取得"""
    for root, _, files in os.walk(input_dir):
        for file in sorted(files):
            if file.endswith(SUPPORTED_EXTENSIONS):
                yield os.path.join(root, file)

def validate_frames(input_path):
    """動画内の画面が認識できるフレームの開始・終了時間を検出"""
    result = subprocess.run(
        ['ffmpeg', '-i', input_path, '-vf', BLACKDETECT_FILTER, '-an', '-f', 'null', '-'],
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        text=True
    )
    for line in result.stderr.split('\n'):
        if 'black_start' in line:
            video_start = line.split('black_start:')[1].split(' ')[0]
            video_end = line.split('black_end:')[1].split(' ')[0]
            return float(video_start), float(video_end)
    return None, None

def trim_video(input_path, video_start, output_path):
    """動画をトリミング"""
    try:
        subprocess.run(
            ['ffmpeg', '-i', input_path,
             '-vf', f"trim=start_frame={video_start},setpts=PTS-STARTPTS",
             '-af', f"atrim=start_sample={video_start},asetpts=PTS-STARTPTS",
             output_path],
            check=True
        )
    except subprocess.CalledProcessError as e:
        print(f"Error trimming video {input_path}: {e}")
        sys.exit(1)

def process_videos(input_dir, output_dir):
    """動画ファイルを処理"""
    validate_directory(input_dir, "input")
    validate_directory(output_dir, "output")

    for input_path in get_video_files(input_dir):
        video_start, video_end = validate_frames(input_path)
        if video_start is not None:
            output_path = os.path.join(output_dir, os.path.basename(input_path))
            print(f"Processing {input_path} (start: {video_start}, end: {video_end})")
            trim_video(input_path, video_start, output_path)
        else:
            print(f"No valid frames detected in {input_path}")

def main():
    parser = argparse.ArgumentParser(description="Video trimming")
    parser.add_argument("input_dir", type=str, help="Input directory containing videos")
    parser.add_argument("output_dir", type=str, help="Output directory for trimmed videos")
    args = parser.parse_args()

    process_videos(args.input_dir, args.output_dir)

if __name__ == "__main__":
    main()