我有一个有趣的设置。我有四个视频，它们的持续时间相同，帧速率相同，并且具有相同的PTS时间戳。我希望将这四个视频流传输到RTMP服务器，但保持它们同步，以便在流之间切换的人不会向前跳或向后跳，而是在他们离开的地方继续。
这是我目前正在使用的命令：
ffmpeg \
-re -stream_loop -1 -fflags +genpts -i 01.mp4 \
-re -stream_loop -1 -fflags +genpts -i 02.mp4 \
-re -stream_loop -1 -fflags +genpts -i 03.mp4 \
-re -stream_loop -1 -fflags +genpts -i 04.mp4 \
-map 0:v -map 0:a \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/01 \
-map 1:v -map 1:a \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/02 \
-map 2:v -map 2:a \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/03 \
-map 3:v -map 3:a \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/04
此命令正确地同步流并广播所有四个，但是视频结束的那一刻也是如此。由于-stream_loop -1我希望视频能够无限循环。当流消亡时，这是stdout的输出：
[flv @ 0x2392d40] Failed to update header with correct duration.
[flv @ 0x2392d40] Failed to update header with correct filesize.
[flv @ 0x229b980] Failed to update header with correct duration.
[flv @ 0x229b980] Failed to update header with correct filesize.
[flv @ 0x22f3bc0] Failed to update header with correct duration.
[flv @ 0x22f3bc0] Failed to update header with correct filesize.
[flv @ 0x23a4240] Failed to update header with correct duration.
[flv @ 0x23a4240] Failed to update header with correct filesize.
[libx264 @ 0x25ebd00] frame I:236 Avg QP:29.17 size: 20892
[libx264 @ 0x25ebd00] frame P:5412 Avg QP:32.33 size: 1892
[libx264 @ 0x25ebd00] mb I I16..4: 100.0% 0.0% 0.0%
[libx264 @ 0x25ebd00] mb P I16..4: 0.2% 0.0% 0.0% P16..4: 18.5% 0.0% 0.0% 0.0% 0.0% skip:81.3%
[libx264 @ 0x25ebd00] final ratefactor: 31.62
[libx264 @ 0x25ebd00] coded y,uvDC,uvAC intra: 68.8% 62.8% 34.6% inter: 8.8% 1.8% 0.0%
[libx264 @ 0x25ebd00] i16 v,h,dc,p: 38% 25% 19% 18%
[libx264 @ 0x25ebd00] i8c dc,h,v,p: 40% 22% 27% 11%
[libx264 @ 0x25ebd00] kb/s:515.11
[libspeex @ 0x2537580] 1 frames left in the queue on closing
[libx264 @ 0x2531d00] frame I:236 Avg QP:31.85 size: 15843
[libx264 @ 0x2531d00] frame P:5412 Avg QP:34.95 size: 2086
[libx264 @ 0x2531d00] mb I I16..4: 100.0% 0.0% 0.0%
[libx264 @ 0x2531d00] mb P I16..4: 2.8% 0.0% 0.0% P16..4: 37.8% 0.0% 0.0% 0.0% 0.0% skip:59.4%
[libx264 @ 0x2531d00] final ratefactor: 32.38
[libx264 @ 0x2531d00] coded y,uvDC,uvAC intra: 48.4% 40.8% 13.5% inter: 12.1% 4.0% 0.0%
[libx264 @ 0x2531d00] i16 v,h,dc,p: 41% 21% 26% 13%
[libx264 @ 0x2531d00] i8c dc,h,v,p: 48% 20% 24% 8%
[libx264 @ 0x2531d00] kb/s:510.33
[libspeex @ 0x2533080] 1 frames left in the queue on closing
[libx264 @ 0x22da600] frame I:236 Avg QP:26.11 size: 13705
[libx264 @ 0x22da600] frame P:5412 Avg QP:29.17 size: 2185
[libx264 @ 0x22da600] mb I I16..4: 100.0% 0.0% 0.0%
[libx264 @ 0x22da600] mb P I16..4: 4.5% 0.0% 0.0% P16..4: 35.2% 0.0% 0.0% 0.0% 0.0% skip:60.3%
[libx264 @ 0x22da600] final ratefactor: 28.44
[libx264 @ 0x22da600] coded y,uvDC,uvAC intra: 37.1% 40.1% 10.4% inter: 12.3% 6.2% 0.1%
[libx264 @ 0x22da600] i16 v,h,dc,p: 40% 21% 22% 17%
[libx264 @ 0x22da600] i8c dc,h,v,p: 43% 18% 28% 11%
[libx264 @ 0x22da600] kb/s:511.43
[libspeex @ 0x22db080] 1 frames left in the queue on closing
[libx264 @ 0x22d7a00] frame I:236 Avg QP:30.31 size: 13811
[libx264 @ 0x22d7a00] frame P:5412 Avg QP:33.28 size: 2209
[libx264 @ 0x22d7a00] mb I I16..4: 100.0% 0.0% 0.0%
[libx264 @ 0x22d7a00] mb P I16..4: 5.4% 0.0% 0.0% P16..4: 37.4% 0.0% 0.0% 0.0% 0.0% skip:57.2%
[libx264 @ 0x22d7a00] final ratefactor: 31.52
[libx264 @ 0x22d7a00] coded y,uvDC,uvAC intra: 37.9% 36.7% 9.5% inter: 11.4% 5.0% 0.1%
[libx264 @ 0x22d7a00] i16 v,h,dc,p: 41% 23% 21% 16%
[libx264 @ 0x22d7a00] i8c dc,h,v,p: 45% 19% 27% 9%
[libx264 @ 0x22d7a00] kb/s:516.78
[libspeex @ 0x22d8d80] 1 frames left in the queue on closing
我的FFMPEG版本：
$ ffmpeg -version
ffmpeg version N-90065-g8a8d0b3 Copyright (c) 2000-2018 the FFmpeg developers
built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.5) 20160609
configuration: --prefix=/home/sbarnett/ffmpeg_build --pkg-config-flags=--static --extra-cflags=-I/home/sbarnett/ffmpeg_build/include --extra-ldflags=-L/home/sbarnett/ffmpeg_build/lib --extra-libs='-lpthread -lm' --bindir=/home/sbarnett/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libspeex --enable-nonfree
libavutil 56. 7.101 / 56. 7.101
libavcodec 58. 11.101 / 58. 11.101
libavformat 58. 9.100 / 58. 9.100
libavdevice 58. 1.100 / 58. 1.100
libavfilter 7. 12.100 / 7. 12.100
libswscale 5. 0.101 / 5. 0.101
libswresample 3. 0.101 / 3. 0.101
libpostproc 55. 0.100 / 55. 0.100
如何让视频无限循环？为什么-stream_loop -1无效？
根据@ Gyan的建议，我尝试将filter_complex与电影过滤器一起使用，但是我可能做错了：
ffmpeg \
-stream_loop -1 \
-re -i 01.mp4 \
-re -i 02.mp4 \
-re -i 03.mp4 \
-re -i 04.mp4 \
-filter_complex \
"movie=01.mp4:loop=0[v1];[v1]setpts=N/FRAME_RATE/TB[v1];
amovie=01.mp4:loop=0[a1];[a1]asetpts=N/SR/TB[a1];
movie=02.mp4:loop=0[v2];[v2]setpts=N/FRAME_RATE/TB[v2];
amovie=02.mp4:loop=0[a2];[a2]asetpts=N/SR/TB[a2];
movie=03.mp4:loop=0[v3];[v3]setpts=N/FRAME_RATE/TB[v3];
amovie=03.mp4:loop=0[a3];[a3]asetpts=N/SR/TB[a3];
movie=04.mp4:loop=0[v4];[v4]setpts=N/FRAME_RATE/TB[v4];
amovie=04.mp4:loop=0[a4];[a4]asetpts=N/SR/TB[a4]" \
-map "[v1]" -map "[a1]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/01 \
-map "[v2]" -map "[a2]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/02 \
-map "[v3]" -map "[a3]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/03 \
-map "[v4]" -map "[a4]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/04
这引发了以下错误：
[libspeex @ 0x23f4d80] nb_samples (325) != frame_size (320) (avcodec_encode_audio2)
答案 0 :(得分：1)
stream_loop;你必须使用电影过滤器。
ffmpeg \
-filter_complex \
"movie=01.mp4:loop=0,setpts=N/FRAME_RATE/TB,realtime[v1];
amovie=01.mp4:loop=0,asetpts=N/SR/TB,arealtime[a1];
movie=02.mp4:loop=0,setpts=N/FRAME_RATE/TB,realtime[v2];
amovie=02.mp4:loop=0,asetpts=N/SR/TB,arealtime[a2];
movie=03.mp4:loop=0,setpts=N/FRAME_RATE/TB,realtime[v3];
amovie=03.mp4:loop=0,asetpts=N/SR/TB,arealtime[a3];
movie=04.mp4:loop=0,setpts=N/FRAME_RATE/TB,realtime[v4];
amovie=04.mp4:loop=0,asetpts=N/SR/TB,arealtime[a4]" \
-map "[v1]" -map "[a1]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/01 \
-map "[v2]" -map "[a2]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/02 \
-map "[v3]" -map "[a3]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/03 \
-map "[v4]" -map "[a4]" \
-c:a speex -ar 16000 -ac 1 \
-c:v libx264 -preset ultrafast \
-b:v 500k -b:a 32k \
-f flv rtmp://output/04