我正在试验trim和concat过滤器。
我只想将视频分成 X 个块，然后再次concat。我希望结果将是具有相同帧 / 持续时间的视频。
所以我有一个以 1 fps 编码的视频，包含 3帧，该视频的持续时间为 3秒。
我运行以下脚本
ffmpeg -y -i fps.mp4 -an -filter_complex "[0:v]trim=0:1[v1];[0:v]trim=1:2[v2];[0:v]trim=2:3[v3];[v1][v2][v3] concat=n=3:v=1 [out]" -map [out] out.mp4
结果是一段持续时间为 4秒的视频，用于检查我打过的问题：
ffprobe -print_format json -show_frames out.mp4
它表明现在有 4 个帧？？ （这里是转储）
ffprobe version 4.1.3 Copyright (c) 2007-2019 the FFmpeg developers
built with Apple LLVM version 10.0.1 (clang-1001.0.46.3)
configuration: --prefix=/usr/local/Cellar/ffmpeg/4.1.3 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags='-I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include -I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include/darwin' --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-videotoolbox --disable-libjack --disable-indev=jack --enable-libaom --enable-libsoxr
libavutil 56. 22.100 / 56. 22.100
libavcodec 58. 35.100 / 58. 35.100
libavformat 58. 20.100 / 58. 20.100
libavdevice 58. 5.100 / 58. 5.100
libavfilter 7. 40.101 / 7. 40.101
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 3.100 / 5. 3.100
libswresample 3. 3.100 / 3. 3.100
libpostproc 55. 3.100 / 55. 3.100
{
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'out.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.20.100
Duration: 00:00:04.00, start: 0.000000, bitrate: 4 kb/s
Stream #0:0(und): Video: h264 (High 4:4:4 Predictive) (avc1 / 0x31637661), yuv444p, 100x100, 2 kb/s, 1 fps, 1 tbr, 16384 tbn, 2 tbc (default)
Metadata:
handler_name : VideoHandler
"frames": [
{
"media_type": "video",
"stream_index": 0,
"key_frame": 1,
"pkt_pts": 0,
"pkt_pts_time": "0.000000",
"pkt_dts": 0,
"pkt_dts_time": "0.000000",
"best_effort_timestamp": 0,
"best_effort_timestamp_time": "0.000000",
"pkt_duration": 16384,
"pkt_duration_time": "1.000000",
"pkt_pos": "48",
"pkt_size": "857",
"width": 100,
"height": 100,
"pix_fmt": "yuv444p",
"pict_type": "I",
"coded_picture_number": 0,
"display_picture_number": 0,
"interlaced_frame": 0,
"top_field_first": 0,
"repeat_pict": 0,
"chroma_location": "left"
},
{
"media_type": "video",
"stream_index": 0,
"key_frame": 0,
"pkt_pts": 16384,
"pkt_pts_time": "1.000000",
"pkt_dts": 16384,
"pkt_dts_time": "1.000000",
"best_effort_timestamp": 16384,
"best_effort_timestamp_time": "1.000000",
"pkt_duration": 16384,
"pkt_duration_time": "1.000000",
"pkt_pos": "1053",
"pkt_size": "146",
"width": 100,
"height": 100,
"pix_fmt": "yuv444p",
"pict_type": "B",
"coded_picture_number": 2,
"display_picture_number": 0,
"interlaced_frame": 0,
"top_field_first": 0,
"repeat_pict": 0,
"chroma_location": "left"
},
{
"media_type": "video",
"stream_index": 0,
"key_frame": 0,
"pkt_pts": 32768,
"pkt_pts_time": "2.000000",
"best_effort_timestamp": 32768,
"best_effort_timestamp_time": "2.000000",
"pkt_duration": 16384,
"pkt_duration_time": "1.000000",
"pkt_pos": "1199",
"pkt_size": "19",
"width": 100,
"height": 100,
"pix_fmt": "yuv444p",
"pict_type": "B",
"coded_picture_number": 3,
"display_picture_number": 0,
"interlaced_frame": 0,
"top_field_first": 0,
"repeat_pict": 0,
"chroma_location": "left"
},
{
"media_type": "video",
"stream_index": 0,
"key_frame": 0,
"pkt_pts": 49152,
"pkt_pts_time": "3.000000",
"best_effort_timestamp": 49152,
"best_effort_timestamp_time": "3.000000",
"pkt_duration": 16384,
"pkt_duration_time": "1.000000",
"pkt_pos": "905",
"pkt_size": "148",
"width": 100,
"height": 100,
"pix_fmt": "yuv444p",
"pict_type": "P",
"coded_picture_number": 1,
"display_picture_number": 0,
"interlaced_frame": 0,
"top_field_first": 0,
"repeat_pict": 0,
"chroma_location": "left"
}
]
}
我尝试了不同的方法，如果我分割了2秒的视频（仍为1 fps）并再次连接，一切似乎都可以正常工作。但是，如果超出这一范围，就会出问题吗？
此处是ffmpeg -i fps.mp4的输出
ffmpeg version 4.1.3 Copyright (c) 2000-2019 the FFmpeg developers
built with Apple LLVM version 10.0.1 (clang-1001.0.46.3)
configuration: --prefix=/usr/local/Cellar/ffmpeg/4.1.3 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags='-I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include -I/Library/Java/JavaVirtualMachines/openjdk-12.jdk/Contents/Home/include/darwin' --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-videotoolbox --disable-libjack --disable-indev=jack --enable-libaom --enable-libsoxr
libavutil 56. 22.100 / 56. 22.100
libavcodec 58. 35.100 / 58. 35.100
libavformat 58. 20.100 / 58. 20.100
libavdevice 58. 5.100 / 58. 5.100
libavfilter 7. 40.101 / 7. 40.101
libavresample 4. 0. 0 / 4. 0. 0
libswscale 5. 3.100 / 5. 3.100
libswresample 3. 3.100 / 3. 3.100
libpostproc 55. 3.100 / 55. 3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'scripts/fps.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.20.100
Duration: 00:00:03.00, start: 0.000000, bitrate: 7 kb/s
Stream #0:0(und): Video: h264 (High 4:4:4 Predictive) (avc1 / 0x31637661), gbrp(tv, gbr/unknown/unknown), 100x100, 4 kb/s, 1 fps, 1 tbr, 16384 tbn, 2 tbc (default)
Metadata:
handler_name : VideoHandler