有人有这方面的经验吗？
到目前为止，我已经尝试通过 udp 将 ffmpeg（使用 libx264 和 libaacplus）复用到 mpegts 中，但是 mpegts 复用器显然已损坏（已从多个不同来源确认）。 我也尝试过使用 vlc，但它只能编码 AAC-LC 而不能编码 HE-AAC v2 (aacplus)。
无论如何，我需要解决的问题是有几个不同的地理位置，覆盖着网络摄像头，我需要 udp 能够一直有传入的流，而不用担心网络起伏（udp 将继续当网络再次启动时发送数据包）。那么，你们中的任何人是否有任何使用 h264 和 aacplus over udp 协议的流式直播媒体的经验，如果有，请给我任何链接或指导如何完成它。
非常感谢。
【问题讨论】：
我正在开发一种 DVR 系统，它必须定期从视频设备录制 h264 文件，同时提供本地预览以允许调整视频参数和摄像机视图。虽然我根本不是这个领域的专家，但我在通过 UDP 流式传输 h264 方面取得了相对成功，所以我会尝试分享什么没有，什么对我有用，这一切都是基于 ffmpeg 作为服务器（在我的情况下没有音频）。
最初，我已将我的应用程序设置为同时将视频录制到文件中并将其提供给 .ffm 文件，以便 ffserver 使用 RTP/UDP 将其流式传输以进行相机预览。这种方法的问题在于，当馈送 ffmpeg 进程停止更改视频文件时，预览将停止并且永远不会恢复，尽管随后的 ffmpeg 进程已经开始再次馈送 ffserver。使用 RTP ffserver 显然抱怨帧时间戳从 0 开始，而不是从它们停止的地方继续。然后我意识到，如果我能够通过纯 UDP 发送 h264 数据包，我将获得与您描述的完全相同的效果，一旦下一个 ffmpeg 进程接管，预览就会恢复。
在尝试理解 ffmpeg 文档时，我也尝试使用 mpegts 格式，但这样做我在另一端的播放器上获取 MPEG2 视频（这显示了一个多播地址，但它也适用于特定目标）：
$ ffmpeg -y -f video4linux2 -i /dev/video2 -vcodec libx264 -preset ultrafast /mnt/hd/video.mp4 -an -f mpegts udp://224.124.0.1:5000
ffmpeg version N-35860-g62adc60, Copyright (c) 2000-2011 the FFmpeg developers
built on Dec 16 2011 09:47:41 with gcc 4.5.3
configuration: --prefix=/usr --libdir=/usr/lib --shlibdir=/usr/lib --mandir=/usr/man --disable-debug --enable-shared --disable-static --enab
le-pthreads --enable-libtheora --enable-libvorbis --enable-gpl --enable-version3 --enable-postproc --enable-swscale --enable-avfilter --enable
-libx264 --enable-libvpx --enable-librtmp --disable-indev='v4l,dv1394'
libavutil 51. 32. 0 / 51. 32. 0
libavcodec 53. 46. 0 / 53. 46. 0
libavformat 53. 26. 0 / 53. 26. 0
libavdevice 53. 4. 0 / 53. 4. 0
libavfilter 2. 53. 0 / 2. 53. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 51. 2. 0 / 51. 2. 0
[video4linux2,v4l2 @ 0x8a96b00] Estimating duration from bitrate, this may be inaccurate
Input #0, video4linux2,v4l2, from '/dev/video2':
Duration: N/A, start: 1325538250.366878, bitrate: 27620 kb/s
Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 320x240, 27620 kb/s, 29.97 tbr, 1000k tbn, 29.97 tbc
[buffer @ 0x8a9d8c0] w:320 h:240 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[buffer @ 0x8a9c860] w:320 h:240 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[libx264 @ 0x8a97780] using cpu capabilities: MMX2 Cache64
[libx264 @ 0x8a97780] profile Constrained Baseline, level 1.3
[libx264 @ 0x8a97780] 264 - core 120 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html - options: cabac=0 ref=
1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11
fast_pskip=1 chroma_qp_offset=0 threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=
0 keyint=250 keyint_min=25 scenecut=0 intra_refresh=0 rc=crf mbtree=0 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=0
[mpegts @ 0x8a98100] muxrate VBR, pcr every 2 pkts, sdt every 200, pat/pmt every 40 pkts
Output #0, mp4, to '/mnt/hd/video.mp4':
Metadata:
encoder : Lavf53.26.0
Stream #0:0: Video: h264 (![0][0][0] / 0x0021), yuv420p, 320x240, q=-1--1, 30k tbn, 29.97 tbc
Output #1, mpegts, to 'udp://224.124.0.1:5000':
Metadata:
encoder : Lavf53.26.0
Stream #1:0: Video: mpeg2video, yuv420p, 320x240, q=2-31, 200 kb/s, 90k tbn, 29.97 tbc
Stream mapping:
Stream #0:0 -> #0:0 (rawvideo -> libx264)
Stream #0:0 -> #1:0 (rawvideo -> mpeg2video)
Press [q] to stop, [?] for help
在客户端 PC 上，我可以使用 ffplay 观看视频，而且确实是 MPEG2 格式：
$ ffplay -f mpegts udp://224.124.0.1:5000
ffplay version N-35860-g62adc60, Copyright (c) 2003-2011 the FFmpeg developers
built on Dec 16 2011 09:47:41 with gcc 4.5.3
configuration: --prefix=/usr --libdir=/usr/lib --shlibdir=/usr/lib --mandir=/usr/man --disable-debug --enable-shared --disable-static --enable-pthreads --enable-libtheora --enable-libvorbis --enable-gpl --enable-version3 --enable-postproc --enable-swscale --enable-avfilter --enable-libx264 --enable-libvpx --enable-librtmp --disable-indev='v4l,dv1394'
libavutil 51. 32. 0 / 51. 32. 0
libavcodec 53. 46. 0 / 53. 46. 0
libavformat 53. 26. 0 / 53. 26. 0
libavdevice 53. 4. 0 / 53. 4. 0
libavfilter 2. 53. 0 / 2. 53. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 51. 2. 0 / 51. 2. 0
[mpegts @ 0x80f02e0] Unable to seek back to the start
[mpeg2video @ 0x8111a00] mpeg_decode_postinit() failure
Last message repeated 6 times
[mpegts @ 0x80f02e0] max_analyze_duration 5000000 reached at 5005000
[mpegts @ 0x80f02e0] Estimating duration from bitrate, this may be inaccurate
Input #0, mpegts, from 'udp://224.124.0.1:5000':
Duration: N/A, start: 255.420433, bitrate: 104857 kb/s
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p, 320x240 [SAR 1:1 DAR 4:3], 104857 kb/s, 30.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
VLC 也可以播放流，但只有在指定开关 --demux ffmpeg 之后（感谢this）：
vlc -vv --demux ffmpeg udp://@224.124.0.1:5000
由于我也希望预览在 h264 中，但我已经对文件进行了编码，因此我尝试使用复制编解码器进行 UDP 流传输，但 ffmpeg 因段错误而失败（包含的版本以供参考）：
ffmpeg -y -f video4linux2 -i /dev/video2 -vcodec libx264 -preset ultrafast /mnt/hd/video.mp4 -an -vcodec cop
y -f h264 udp://224.124.0.1:5000
ffmpeg version N-35860-g62adc60, Copyright (c) 2000-2011 the FFmpeg developers
built on Dec 16 2011 09:47:41 with gcc 4.5.3
configuration: --prefix=/usr --libdir=/usr/lib --shlibdir=/usr/lib --mandir=/usr/man --disable-debug --enable-shared --disable-static --enab
le-pthreads --enable-libtheora --enable-libvorbis --enable-gpl --enable-version3 --enable-postproc --enable-swscale --enable-avfilter --enable
-libx264 --enable-libvpx --enable-librtmp --disable-indev='v4l,dv1394'
libavutil 51. 32. 0 / 51. 32. 0
libavcodec 53. 46. 0 / 53. 46. 0
libavformat 53. 26. 0 / 53. 26. 0
libavdevice 53. 4. 0 / 53. 4. 0
libavfilter 2. 53. 0 / 2. 53. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 51. 2. 0 / 51. 2. 0
[video4linux2,v4l2 @ 0x92c7b00] Estimating duration from bitrate, this may be inaccurate
Input #0, video4linux2,v4l2, from '/dev/video2':
Duration: N/A, start: 1325539132.411691, bitrate: 27620 kb/s
Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 320x240, 27620 kb/s, 29.97 tbr, 1000k tbn, 29.97 tbc
[buffer @ 0x92ce860] w:320 h:240 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[libx264 @ 0x92c8780] using cpu capabilities: MMX2 Cache64
[libx264 @ 0x92c8780] profile Constrained Baseline, level 1.3
[libx264 @ 0x92c8780] 264 - core 120 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html - options: cabac=0 ref=
1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11
fast_pskip=1 chroma_qp_offset=0 threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=
0 keyint=250 keyint_min=25 scenecut=0 intra_refresh=0 rc=crf mbtree=0 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=0
Output #0, mp4, to '/mnt/hd/video.mp4':
Metadata:
encoder : Lavf53.26.0
Stream #0:0: Video: h264 (![0][0][0] / 0x0021), yuv420p, 320x240, q=-1--1, 30k tbn, 29.97 tbc
Output #1, h264, to 'udp://224.124.0.1:5000':
Metadata:
encoder : Lavf53.26.0
Stream #1:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 320x240, q=2-31, 27620 kb/s, 90k tbn, 29.97 tbc
Stream mapping:
Stream #0:0 -> #0:0 (rawvideo -> libx264)
Stream #0:0 -> #1:0 (copy)
Press [q] to stop, [?] for help
Segmentation fault
虽然不太理想，但为 UDP 流部分指定格式 h264 会导致第二次并发 h264 转换，但它确实有效：
$ ffmpeg -y -f video4linux2 -i /dev/video2 -vcodec libx264 -preset ultrafast /mnt/hd/video.mp4 -an -f h264 -preset ultrafast udp://224.124.0.1:5000
ffmpeg version N-35860-g62adc60, Copyright (c) 2000-2011 the FFmpeg developers
built on Dec 16 2011 09:47:41 with gcc 4.5.3
configuration: --prefix=/usr --libdir=/usr/lib --shlibdir=/usr/lib --mandir=/usr/man --disable-debug --enable-shared --disable-static --enab
le-pthreads --enable-libtheora --enable-libvorbis --enable-gpl --enable-version3 --enable-postproc --enable-swscale --enable-avfilter --enable
-libx264 --enable-libvpx --enable-librtmp --disable-indev='v4l,dv1394'
libavutil 51. 32. 0 / 51. 32. 0
libavcodec 53. 46. 0 / 53. 46. 0
libavformat 53. 26. 0 / 53. 26. 0
libavdevice 53. 4. 0 / 53. 4. 0
libavfilter 2. 53. 0 / 2. 53. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 51. 2. 0 / 51. 2. 0
[video4linux2,v4l2 @ 0x913ab00] Estimating duration from bitrate, this may be inaccurate
Input #0, video4linux2,v4l2, from '/dev/video2':
Duration: N/A, start: 1325539689.729735, bitrate: 27620 kb/s
Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 320x240, 27620 kb/s, 29.97 tbr, 1000k tbn, 29.97 tbc
[buffer @ 0x9141840] w:320 h:240 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[buffer @ 0x913e480] w:320 h:240 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[libx264 @ 0x913b780] using cpu capabilities: MMX2 Cache64
[libx264 @ 0x913b780] profile Constrained Baseline, level 1.3
[libx264 @ 0x913b780] 264 - core 120 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html - options: cabac=0 ref=
1 deblock=0:0:0 analyse=0:0 me=dia subme=0 psy=1 psy_rd=1.00:0.00 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0 deadzone=21,11
fast_pskip=1 chroma_qp_offset=0 threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=
0 keyint=250 keyint_min=25 scenecut=0 intra_refresh=0 rc=crf mbtree=0 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=0
[libx264 @ 0x913c820] using cpu capabilities: MMX2 Cache64
[libx264 @ 0x913c820] profile Constrained Baseline, level 1.3
Output #0, mp4, to '/mnt/hd/video.mp4':
Metadata:
encoder : Lavf53.26.0
Stream #0:0: Video: h264 (![0][0][0] / 0x0021), yuv420p, 320x240, q=-1--1, 30k tbn, 29.97 tbc
Output #1, h264, to 'udp://224.124.0.1:5000':
Metadata:
encoder : Lavf53.26.0
Stream #1:0: Video: h264, yuv420p, 320x240, q=-1--1, 90k tbn, 29.97 tbc
Stream mapping:
Stream #0:0 -> #0:0 (rawvideo -> libx264)
Stream #0:0 -> #1:0 (rawvideo -> libx264)
Press [q] to stop, [?] for help
在客户端ffplay反复抱怨缺少一些信息，但过了几秒它终于出现了视频，还可以，但有点断断续续：
$ ffplay -f h264 udp://224.124.0.1:5000
[h264 @ 0xa0be740] non-existing PPS referenced
[h264 @ 0xa0be740] non-existing PPS 0 referenced
[h264 @ 0xa0be740] decode_slice_header error
[h264 @ 0xa0be740] no frame!
(...)
[h264 @ 0xa0be740] non-existing PPS referenced
[h264 @ 0xa0be740] non-existing PPS 0 referenced
[h264 @ 0xa0be740] decode_slice_header error
[h264 @ 0xa0be740] no frame!
[h264 @ 0xa0e72e0] max_analyze_duration 5000000 reached at 5013967
[h264 @ 0xa0e72e0] Estimating duration from bitrate, this may be inaccurate
Input #0, h264, from 'udp://224.124.0.1:5000':
Duration: N/A, bitrate: N/A
Stream #0:0: Video: h264 (Constrained Baseline), yuv420p, 320x240, 47.27 fps, 29.97 tbr, 1200k tbn, 59.94 tbc
[h264 @ 0xa0be740] Missing reference picture
[h264 @ 0xa0be740] decode_slice_header error
[h264 @ 0xa0be740] concealing 300 DC, 300 AC, 300 MV errors
[h264 @ 0xa0be740] Missing reference picture 0KB sq= 0B f=0/0 0/0
[h264 @ 0xa0be740] decode_slice_header error
[h264 @ 0xa0be740] mmco: unref short failure
[h264 @ 0xa0be740] concealing 300 DC, 300 AC, 300 MV errors
10.78 A-V: 0.000 fd= 0 aq= 0KB vq= 0KB sq= 0B f=0/0
然后我尝试 VLC 使用相同的 ''--demux ffmpeg'' 开关；它还抱怨 SPS/PPS（还不知道是什么），但最后它播放视频真的很流畅：
$ vlc -v --demux ffmpeg udp/h264://@224.124.0.1:5000
VLC media player 1.1.12 The Luggage (revision exported)
Blocked: call to unsetenv("DBUS_ACTIVATION_ADDRESS")
Blocked: call to unsetenv("DBUS_ACTIVATION_BUS_TYPE")
[0x943346c] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
Blocked: call to setlocale(6, "")
Blocked: call to setlocale(6, "")
[0x94cde8c] qt4 interface error: Unable to load extensions module
[0x96720e4] h264 demux error: this doesn't look like a H264 ES stream, continuing anyway
[0x963989c] access_udp access warning: unimplemented query in control
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x967328c] packetizer_h264 demux packetizer warning: waiting for SPS/PPS
[0x94be644] main input error: Invalid PCR value in ES_OUT_SET_(GROUP_)PCR !
[0xb2a325f4] avcodec decoder warning: disabling direct rendering
[0x96dfac4] main video output warning: vlc_object_find_name(postproc) is not safe!
[0x94c2474] signals interface warning: signal 17 overridden (0xb6f31030)
[0x94c2474] signals interface warning: /usr/lib/qt/lib/libQtCore.so.4(?)[(nil)]
[0x96dfac4] main video output warning: late picture skipped (32703 > -4)
我仍在尝试找出缺少的内容，但结果已经令人满意。播放 VLC 后，当我在另一端重新启动 ffmpeg 时，我可以停止播放暂停并立即恢复的馈送 ffmpeg。
希望这能有所帮助，如果您有任何关于使用 h264 作为所选格式代替 mpegts 的其他信息，请告诉我 - 我怀疑缺少的 SPS/PPS 信息可能与此有关。
【讨论】：