我在保存流媒体时遇到问题ffmpeg。问题是视频与音频不同步。
视频在音频前 2-3 秒出现。
我尝试删除和编辑选项，但没有任何改变，我也进行了一些研究，并尝试了此处发布的这个很好的答案中描述的所有解决方案，但它对我不起作用。
我试图从播放列表中下载一个块，并且我有一个.ts音频/视频同步的文件。
如果我播放流媒体，VLC player我可以在几秒钟内听到没有视频的音频，然后视频会出现并与音频同步。
ffplay也可以正确播放相同的流：音频和视频编解码器中似乎有时间信息，并且可以正确同步播放。
如何让 ffmpeg 同步音频和视频？
如果您需要 ffmpeg 或 ffplay 输出，我会发布它们。
编辑：根据要求，我报告了一个简单命令的完整 ffmpeg 输出，以将流输出保存到文件：
$ ffmpeg -i http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/master.m3u8?hdnts=st=1554271074~exp=1554271524~acl=/*~hmac=14df2434241f7fd52f5a6012094367180f8567a1a733f7ef9eeef3dc7b46ebb2 -c copy out.mp4
ffmpeg version 3.4.2 Copyright (c) 2000-2018 the FFmpeg developers
built with Apple LLVM version 9.0.0 (clang-900.0.39.2)
configuration: --prefix=/usr/local/Cellar/ffmpeg/3.4.2 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --disable-jack --enable-gpl --enable-ffplay --enable-libmp3lame --enable-libopus --enable-librtmp --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-opencl --enable-videotoolbox --enable-openssl --disable-lzma --enable-nonfree
libavutil 55. 78.100 / 55. 78.100
libavcodec 57.107.100 / 57.107.100
libavformat 57. 83.100 / 57. 83.100
libavdevice 57. 10.100 / 57. 10.100
libavfilter 6.107.100 / 6.107.100
libavresample 3. 7. 0 / 3. 7. 0
libswscale 4. 8.100 / 4. 8.100
libswresample 2. 9.100 / 2. 9.100
libpostproc 54. 7.100 / 54. 7.100
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_2_av-p.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_2_av-b.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_1_av-p.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_1_av-b.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_2_a-p.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_2_a-b.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427138_2_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427138_2_av-b.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427138_1_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427138_1_av-b.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427138_2_a-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427138_2_a-b.ts?sd=10&rebase=on' for reading
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdf0025e00] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] decode_slice_header error
[h264 @ 0x7ffdf0028200] no frame!
[NULL @ 0x7ffdf0025e00] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] decode_slice_header error
[h264 @ 0x7ffdf0028200] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[NULL @ 0x7ffdf0025e00] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[h264 @ 0x7ffdf0028200] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] decode_slice_header error
[h264 @ 0x7ffdf0028200] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[NULL @ 0x7ffdf0025e00] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] decode_slice_header error
[h264 @ 0x7ffdf0028200] no frame!
[NULL @ 0x7ffdf0025e00] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[h264 @ 0x7ffdf0028200] non-existing PPS 0 referenced
[h264 @ 0x7ffdf0028200] decode_slice_header error
[h264 @ 0x7ffdf0028200] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
[NULL @ 0x7ffdef028000] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] non-existing PPS 0 referenced
[h264 @ 0x7ffdef02a400] decode_slice_header error
[h264 @ 0x7ffdef02a400] no frame!
Input #0, hls,applehttp, from 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/master.m3u8?hdnts=st=1554271074~exp=1554271524~acl=/*~hmac=14df2434241f7fd52f5a6012094367180f8567a1a733f7ef9eeef3dc7b46ebb2':
Duration: N/A, start: 65871.264133, bitrate: N/A
Program 0
Metadata:
variant_bitrate : 528000
Stream #0:0: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p(tv), 400x224, 25 fps, 25 tbr, 90k tbn, 50 tbc
Metadata:
variant_bitrate : 528000
Stream #0:1: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 528000
Stream #0:2: Data: timed_id3 (ID3 / 0x20334449)
Metadata:
variant_bitrate : 528000
Program 1
Metadata:
variant_bitrate : 528000
Stream #0:3: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p(tv), 400x224, 25 fps, 25 tbr, 90k tbn, 50 tbc
Metadata:
variant_bitrate : 528000
Stream #0:4: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 528000
Stream #0:5: Data: timed_id3 (ID3 / 0x20334449)
Metadata:
variant_bitrate : 528000
Program 2
Metadata:
variant_bitrate : 1328000
Stream #0:6: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p(tv), 720x404, 25 fps, 25 tbr, 90k tbn, 50 tbc
Metadata:
variant_bitrate : 1328000
Stream #0:7: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 1328000
Stream #0:8: Data: timed_id3 (ID3 / 0x20334449)
Metadata:
variant_bitrate : 1328000
Program 3
Metadata:
variant_bitrate : 1328000
Stream #0:9: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p(tv), 720x404, 25 fps, 25 tbr, 90k tbn, 50 tbc
Metadata:
variant_bitrate : 1328000
Stream #0:10: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 1328000
Stream #0:11: Data: timed_id3 (ID3 / 0x20334449)
Metadata:
variant_bitrate : 1328000
Program 4
Metadata:
variant_bitrate : 128000
Stream #0:12: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 128000
Stream #0:13: Data: timed_id3 (ID3 / 0x20334449)
Metadata:
variant_bitrate : 128000
Program 5
Metadata:
variant_bitrate : 128000
Stream #0:14: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 128000
Stream #0:15: Data: timed_id3 (ID3 / 0x20334449)
Metadata:
variant_bitrate : 128000
Output #0, mp4, to 'out.mp4':
Metadata:
encoder : Lavf57.83.100
Stream #0:0: Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv), 720x404, q=2-31, 25 fps, 25 tbr, 90k tbn, 90k tbc
Metadata:
variant_bitrate : 1328000
Stream #0:1: Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp
Metadata:
variant_bitrate : 528000
Stream mapping:
Stream #0:6 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[hls,applehttp @ 0x7ffdef800000] No longer receiving playlist 1rate=1167.5kbits/s speed=4.93x
[hls,applehttp @ 0x7ffdef800000] No longer receiving playlist 5
[hls,applehttp @ 0x7ffdef800000] No longer receiving playlist 3
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427139_2_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427139_1_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] No longer receiving playlist 4
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427140_2_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427140_1_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_1_av-p.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427141_1_av-p.ts?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/index_2_av-p.m3u8?sd=10&rebase=on' for reading
[hls,applehttp @ 0x7ffdef800000] Opening 'http://la7livehls-lh.akamaihd.net/i/livebkup_1@372883/segment155427141_2_av-p.ts?sd=10&rebase=on' for reading
[mp4 @ 0x7ffdf0170600] Non-monotonous DTS in output stream 0:1; previous: 1440768, current: 1439744; changing to 1440769. This may result in incorrect timestamps in the output file.
(...)