FFmpeg命令整合（视频篇）

ffmpeg 是一个非常流行且好用的图像、音视频处理工具。可以实现视频分割，截图，转码，合并，水印处理等常见媒体操作。它的作者也是一个非常厉害的人，感兴趣的同学可以查查。

【视频时长剪切】

# 如果编码格式采用的copy 最好加上
ffmpeg -ss  00:00:00.000 -to 00:10:00.000 -accurate_seek -i input.mp4 -c:v copy -c:a copy  -avoid_negative_ts 1 -y result.mp4

【视频尺寸裁剪】

# width：宽度
# height：高度
# x：横向x的坐标点开始
# y：纵向y的坐标点开始
ffmpeg -i input.mp4 -vf crop=width:height:x:y -y result.mp4

【添加图片水印】

# 可以同时添加很多张图片
ffmpeg -i input.mp4 "-i image01.jpg -i image02.jpg" -filter_complex "overlay=x=50:y=50,overlay=x=100:y=100" -c:a copy -y result.mp4

【视频去水印】

# 可以同时去除多个范围
# x：坐标
# y：坐标
# width：宽度
# height：高度
ffmpeg -i input.mp4 -vf "delogo=x:y:width:height,delogo=x:y:width:height" -c:a copy -y result.mp4

【视频提取音频】

# 这里提取成mp3为例
ffmpeg -i input.mp4 -acodec libmp3lame -vn -y result.mp3

基于mobile-ffmpeg对于格式的支持度，是否支持主要看是否编译了对应的编码到ffmpeg库中

【视频格式转换】

# 注意：假如目标格式是3gp格式，必须加上参数 -ac 1 -ar 8000
#preset：ultrafast、superfast、veryfast、faster、fast、medium、slow、slower、veryslow、placebo
ffmpeg -i input.mp4 -codec:v libx264 -preset superfast -b:v 1280K -s 宽x高 -r 帧率 -y result.mkv

【提取m3u8视频为mp4】

ffmpeg -allowed_extensions ALL -i https://xxx.xxx.com/aaa.m3u8 -codec:v libx264 -codec:a acc -async 2 -ar 44100 -c copy -threads 2 -y result.mp4

【视频转GIF】

# -r：指定帧率
# -s：指定分辨率
# -b:v：指定码率1000K
ffmpeg -i input.mp4 -r 15 -s 270x480 -y result.gif

【参看视频信息】

以JSON形式输出

# -v：调试信息级别（quiet、panic、fatal、error、warning、info、verbose、debug）
ffprobe -i input.mp4 -v quiet -print_format json -show_format -show_streams

# 样例
{
    "streams": [
        {
            "index": 0,
            "codec_name": "h264",
            "codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
            "profile": "High",
            "codec_type": "video",
            "codec_time_base": "659/39360",
            "codec_tag_string": "avc1",
            "codec_tag": "0x31637661",
            "width": 592,
            "height": 1280,
            "coded_width": 592,
            "coded_height": 1280,
            "closed_captions": 0,
            "has_b_frames": 1,
            "pix_fmt": "yuv420p",
            "level": 31,
            "color_range": "tv",
            "color_space": "bt709",
            "color_transfer": "bt709",
            "color_primaries": "bt709",
            "chroma_location": "left",
            "refs": 1,
            "is_avc": "true",
            "nal_length_size": "4",
            "r_frame_rate": "30/1",
            "avg_frame_rate": "19680/659",
            "time_base": "1/600",
            "start_pts": 0,
            "start_time": "0.000000",
            "duration_ts": 26360,
            "duration": "43.933333",
            "bit_rate": "734637",
            "bits_per_raw_sample": "8",
            "nb_frames": "1312",
            "disposition": {
                "default": 1,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0,
                "timed_thumbnails": 0
            },
            "tags": {
                "creation_time": "2022-04-19T08:03:25.000000Z",
                "language": "und",
                "handler_name": "Core Media Video"
            }
        },
        {
            "index": 1,
            "codec_name": "aac",
            "codec_long_name": "AAC (Advanced Audio Coding)",
            "profile": "LC",
            "codec_type": "audio",
            "codec_time_base": "1/44100",
            "codec_tag_string": "mp4a",
            "codec_tag": "0x6134706d",
            "sample_fmt": "fltp",
            "sample_rate": "44100",
            "channels": 1,
            "channel_layout": "mono",
            "bits_per_sample": 0,
            "r_frame_rate": "0/0",
            "avg_frame_rate": "0/0",
            "time_base": "1/44100",
            "start_pts": 0,
            "start_time": "0.000000",
            "duration_ts": 1936505,
            "duration": "43.911678",
            "bit_rate": "46494",
            "max_bit_rate": "48000",
            "nb_frames": "1894",
            "disposition": {
                "default": 1,
                "dub": 0,
                "original": 0,
                "comment": 0,
                "lyrics": 0,
                "karaoke": 0,
                "forced": 0,
                "hearing_impaired": 0,
                "visual_impaired": 0,
                "clean_effects": 0,
                "attached_pic": 0,
                "timed_thumbnails": 0
            },
            "tags": {
                "creation_time": "2022-04-19T08:03:25.000000Z",
                "language": "und",
                "handler_name": "Core Media Audio"
            }
        }
    ],
    "format": {
        "filename": "input.mp4",
        "nb_streams": 2,
        "nb_programs": 0,
        "format_name": "mov,mp4,m4a,3gp,3g2,mj2",
        "format_long_name": "QuickTime / MOV",
        "start_time": "0.000000",
        "duration": "43.933333",
        "size": "4317459",
        "bit_rate": "786183",
        "probe_score": 100,
        "tags": {
            "major_brand": "mp42",
            "minor_version": "1",
            "compatible_brands": "isommp41mp42",
            "creation_time": "2022-04-19T08:03:25.000000Z",
            "copyright": "",
            "copyright-eng": ""
        }
    }
}