sudo apt install ffmpeg

brew install ffmpeg

ffmpeg -version

ffmpeg -sub_charenc UTF-8 \
-i input.mp4 \
-i subtitle.srt \
-c:v copy \
-c:a copy \
-c:s mov_text \
-metadata:s:s:0 language=chi \
output.mp4

import subprocess
import os
import sys

def validate_file(file_path, file_type="file"):
    """
    校驗文件是否存在
    :param file_path: 文件路徑
    :param file_type: 文件類型描述（用于錯誤提示）
    """
    if not os.path.exists(file_path):
        raise FileNotFoundError(f"{file_type} 不存在: {file_path}")
    print(f"{file_type} 校驗通過: {file_path}")
    return True


def merge_video_with_subtitles(video_path, srt_path, output_path):
    """
    使用 FFmpeg 將 MP4 視頻與 SRT 字幕合并
    不重新編碼視頻和音頻，支持 UTF-8 中文字幕
    """

    # 1. 校驗輸入文件是否存在
    validate_file(video_path, "視頻文件")
    validate_file(srt_path, "字幕文件")

    # 2. 構(gòu)建 FFmpeg 命令
    ffmpeg_cmd = [
        "ffmpeg",

        # 輸入視頻文件
        "-i", video_path,

        # 輸入字幕文件
        "-i", srt_path,

        # 視頻流直接拷貝，不重新編碼
        "-c:v", "copy",

        # 音頻流直接拷貝，不重新編碼
        "-c:a", "copy",

        # 將 SRT 轉(zhuǎn)換為 MP4 支持的 mov_text 字幕格式
        "-c:s", "mov_text",

        # 設(shè)置字幕語言元數(shù)據(jù)為中文
        "-metadata:s:s:0", "language=chi",

        # 輸出文件
        output_path
    ]

    # 3. 強制指定字幕編碼為 UTF-8，防止中文亂碼
    ffmpeg_cmd.insert(3, "-sub_charenc")
    ffmpeg_cmd.insert(4, "UTF-8")

    try:
        # 4. 執(zhí)行 FFmpeg 命令
        result = subprocess.run(
            ffmpeg_cmd,
            check=True,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True
        )
        print(f"字幕合并成功，輸出文件: {output_path}")

    except subprocess.CalledProcessError as e:
        # FFmpeg 執(zhí)行失敗時輸出錯誤信息
        print("FFmpeg 執(zhí)行失敗:")
        print(e.stderr)
        raise

    except Exception as e:
        # 其他異常
        print(f"執(zhí)行過程中發(fā)生錯誤: {e}")
        raise


def main():
    """
    主函數(shù)，定義輸入輸出路徑
    """

    # 視頻文件路徑
    video_path = r"SSYouTube.online_Gesture Drawing Practice _ 20 and 40 sec. poses_1080p.mp4"

    # 字幕文件路徑
    srt_path = r"SSYouTube.online_Gesture Drawing Practice _ 20 and 40 sec. poses_1080p.srt"

    # 輸出視頻路徑
    output_path = "output.mp4"

    # 合并視頻與字幕
    merge_video_with_subtitles(video_path, srt_path, output_path)


if __name__ == "__main__":
    try:
        main()
    except Exception as e:
        print(f"程序異常退出: {e}")
        sys.exit(1)

validate_file(video_path, "video")
validate_file(srt_path, "subtitle")

-sub_charenc UTF-8

-vf subtitles=xxx.srt