FFmpeg rtp streaming was not synchronous

[Ken]

Summary of the bug:
Hello,I use ffmpeg-1.1.3 and deliver stream to darwin server.
First,I create a sdp data.

ffmpeg -f video4linux2 -s 720:480 -i /dev/video0 -f alsa -i hw:0,0 -an -vcodec libx264 -pix_fmt yuv420p -s 176x144 -b 104k -r 12 -profile baseline -level 30 -flags +global_header -f rtp rtp://XXXIP:20000 -vn -flags +global_header -acodec libfaac -ac 1 -ar 16000 -ab 16k -f rtp rtp://XXXIP:20002>test.sdp

SDP Data
SDP:
v=0
o=- 0 0 IN IP4 127.0.0.1
s=No Name
t=0 0
a=tool:libavformat 54.59.106
m=video 20000 RTP/AVP 96
c=IN IP4 XXXIP
b=AS:104
a=rtpmap:96 H264/90000
a=fmtp:96 packetization-mode=1; sprop-parameter-sets=Z0LAHtkCxOhAAAADAEAAAAYDxYuS,aMuMsg==; profile-level-id=42C01E
m=audio 20002 RTP/AVP 97
c=IN IP4 XXXIP
b=AS:16
a=rtpmap:97 MPEG4-GENERIC/16000/1
a=fmtp:97 profile-level-id=1;mode=AAC-hbr;sizelength=13;indexlength=3;indexdeltalength=3; config=1408

Second,I copy the sdp data in Darwin Server /usr/local/movies/
and remove the word "SDP:"

Third,
Play ffmpeg
ffmpeg -f video4linux2 -s 720:480 -i /dev/video0 -f alsa -i hw:0,0 -an -vcodec libx264 -pix_fmt yuv420p -s 176x144 -b 104k -r 12 -profile baseline -level 30 -flags +global_header -f rtp rtp://XXXIP:20000 -vn -flags +global_header -acodec libfaac -ac 1 -ar 16000 -ab 16k -f rtp rtp://XXXIP:20002

But,I use feature phone(rtsp),it has no audio,so I fix the parameter.(add -rtpflags latm)

ffmpeg -f video4linux2 -s 720:480 -i /dev/video0 -f alsa -i hw:0,0 -an -vcodec libx264 -pix_fmt yuv420p -s 176x144 -b 104k -r 12 -profile baseline -level 30 -flags +global_header -f rtp rtp://XXXIP:20000 -vn -flags +global_header -rtpflags latm -acodec libfaac -ac 1 -ar 16000 -ab 16k -f rtp rtp://XXXIP:20002>test.sdp

SDP Data:
SDP:
v=0
o=- 0 0 IN IP4 127.0.0.1
s=No Name
t=0 0
a=tool:libavformat 54.59.106
m=video 20000 RTP/AVP 96
c=IN IP4 XXXIP
b=AS:104
a=rtpmap:96 H264/90000
a=fmtp:96 packetization-mode=1; sprop-parameter-sets=Z0LAHtkCxOhAAAADAEAAAAYDxYuS,aMuMsg==; profile-level-id=42C01E
m=audio 20002 RTP/AVP 97
c=IN IP4 XXXIP
b=AS:16
a=rtpmap:97 MP4A-LATM/16000/1
a=fmtp:97 profile-level-id=40;cpresent=0;config=400028103fc0

It look perfectly,but the sound is faster than video.

So,have anyone known how to sovle it?

Thanks

[Carl Eugen Hoyos]

Replying to Ken_JJ:

It look perfectly,but the sound is faster than video.

Do you mean that when using your command you see progressive A/V desync, ie the stream starts either with some desync or in-sync but A/V sync gets worse and worse over time?
Or do you mean that there is A/V desync from the beginning that stays approximately constant but does not get better?

Is the problem only reproducible if you output to sdp or also if you encode a file?

In any case: Please add the complete, uncut console output together with your command line to make this a valid ticket.

[Ken]

Sorry,for example,(listen sound) ->(after 2~3 s)->(watch match video).
I try other protocol,such as rtmp,the data encode is good,only use rtp protocol the video and audio are desync.

ffmpeg -f video4linux2 -s 720:480 -i /dev/video0 -f alsa -i hw:0,0 -an -vcodec libx264 -pix_fmt yuv420p -s 176x144 -b 104k -r 12 -profile baseline -level 30 -flags +global_header -f rtp rtp://XXXIP:20000 -vn -flags +global_header -rtpflags latm -acodec libfaac -ac 1 -ar 16000 -ab 16k -f rtp rtp://XXXIP:20002
ffmpeg version 1.1.3 Copyright (c) 2000-2013 the FFmpeg developers
  built on Mar 14 2013 13:47:14 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
  configuration: --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libvpx --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-gpl --enable-postproc --enable-nonfree --enable-network --enable-protocol=tcp --enable-demuxer=rtsp --enable-decoder=h264 --enable-zlib
  libavutil      52. 13.100 / 52. 13.100
  libavcodec     54. 86.100 / 54. 86.100
  libavformat    54. 59.106 / 54. 59.106
  libavdevice    54.  3.102 / 54.  3.102
  libavfilter     3. 32.100 /  3. 32.100
  libswscale      2.  1.103 /  2.  1.103
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
[video4linux2,v4l2 @ 0x261c300] Estimating duration from bitrate, this may be inaccurate
Input #0, video4linux2,v4l2, from '/dev/video0':
  Duration: N/A, start: 1363312657.741746, bitrate: 165722 kb/s
    Stream #0:0: Video: rawvideo (YUY2 / 0x32595559), yuyv422, 720x480, 165722 kb/s, 29.97 tbr, 1000k tbn, 29.97 tbc
[alsa @ 0x261cf00] Estimating duration from bitrate, this may be inaccurate
Guessed Channel Layout for  Input Stream #1.0 : stereo
Input #1, alsa, from 'hw:0,0':
  Duration: N/A, start: 1363312657.744649, bitrate: 1536 kb/s
    Stream #1:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
Please use -b:a or -b:v, -b is ambiguous
Please use -profile:a or -profile:v, -profile is ambiguous
[libx264 @ 0x2623a60] using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE4.2 AVX
[libx264 @ 0x2623a60] profile Constrained Baseline, level 3.0
[libx264 @ 0x2623a60] 264 - core 129 - H.264/MPEG-4 AVC codec - Copyleft 2003-2013 - http://www.videolan.org/x264.html - options: cabac=0 ref=3 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=36 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=12 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=104 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, rtp, to 'rtp://XXXIP:20000':
  Metadata:
    encoder         : Lavf54.59.106
    Stream #0:0: Video: h264, yuv420p, 176x144, q=-1--1, 104 kb/s, 90k tbn, 12 tbc
Output #1, rtp, to 'rtp://XXXIP:20002':
  Metadata:
    encoder         : Lavf54.59.106
    Stream #1:0: Audio: aac, 16000 Hz, mono, s16, 16 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo -> libx264)
  Stream #1:0 -> #1:0 (pcm_s16le -> libfaac)
SDP:
v=0
o=- 0 0 IN IP4 127.0.0.1
s=No Name
t=0 0
a=tool:libavformat 54.59.106
m=video 20000 RTP/AVP 96
c=IN IP4 XXXIP
b=AS:104
a=rtpmap:96 H264/90000
a=fmtp:96 packetization-mode=1; sprop-parameter-sets=Z0LAHtkCxOhAAAADAEAAAAYDxYuS,aMuMsg==; profile-level-id=42C01E
m=audio 20002 RTP/AVP 97
c=IN IP4 XXXIP
b=AS:16
a=rtpmap:97 MP4A-LATM/16000/1
a=fmtp:97 profile-level-id=40;cpresent=0;config=400028103fc0

Press [q] to stop, [?] for help
frame=    9 fps=0.0 q=0.0 size=       0kB time=00:00:00.25 bitrate=   0.0kbits/sframe=   16 fps= 16 q=0.0 size=       0kB time=00:00:00.77 bitrate=   0.0kbits/sframe=   22 fps= 15 q=0.0 size=       0kB time=00:00:01.28 bitrate=   0.0kbits/sframe=   28 fps= 14 q=0.0 size=       0kB time=00:00:01.79 bitrate=   0.0kbits/sframe=   34 fps= 14 q=0.0 size=       0kB time=00:00:02.30 bitrate=   0.0kbits/sframe=   40 fps= 13 q=0.0 size=       0kB time=00:00:02.75 bitrate=   0.0kbits/sframe=   46 fps= 13 q=0.0 size=       0kB time=00:00:03.26 bitrate=   0.0kbits/sframe=   52 fps= 13 q=0.0 size=       0kB time=00:00:03.77 bitrate=   0.0kbits/sframe=   58 fps= 13 q=0.0 size=       0kB time=00:00:04.29 bitrate=   0.0kbits/sframe=   64 fps= 13 q=0.0 size=       0kB time=00:00:04.80 bitrate=   0.0kbits/sframe=   70 fps= 13 q=0.0 size=       0kB time=00:00:05.31 bitrate=   0.0kbits/sframe=   76 fps= 13 q=0.0 size=       0kB time=00:00:05.82 bitrate=   0.0kbits/sframe=   82 fps= 13 q=29.0 size=       5kB time=00:00:06.27 bitrate=   6.5kbits/frame=   88 fps= 12 q=25.0 size=       9kB time=00:00:06.78 bitrate=  11.2kbits/frame=   94 fps= 12 q=22.0 size=      11kB time=00:00:07.29 bitrate=  12.1kbits/frame=  100 fps= 12 q=18.0 size=      12kB time=00:00:07.81 bitrate=  12.4kbits/frame=  106 fps= 12 q=20.0 size=      18kB time=00:00:08.32 bitrate=  17.8kbits/frame=  112 fps= 12 q=19.0 size=      21kB time=00:00:08.83 bitrate=  19.3kbits/frame=  118 fps= 12 q=17.0 size=      24kB time=00:00:09.34 bitrate=  20.6kbits/frame=  124 fps= 12 q=17.0 size=      28kB time=00:00:09.79 bitrate=  23.5kbits/frame=  130 fps= 12 q=18.0 size=      35kB time=00:00:10.30 bitrate=  28.1kbits/frame=  136 fps= 12 q=22.0 size=      53kB time=00:00:10.81 bitrate=  40.2kbits/frame=  142 fps= 12 q=22.0 size=      63kB time=00:00:11.32 bitrate=  45.4kbits/frame=  148 fps= 12 q=23.0 size=      76kB time=00:00:11.84 bitrate=  52.8kbits/frame=  154 fps= 12 q=27.0 size=     112kB time=00:00:12.35 bitrate=  74.3kbits/frame=  160 fps= 12 q=30.0 size=     144kB time=00:00:12.86 bitrate=  91.5kbits/frame=  166 fps= 12 q=31.0 size=     164kB time=00:00:13.31 bitrate= 101.0kbits/frame=  172 fps= 12 q=32.0 size=     175kB time=00:00:13.82 bitrate= 103.9kbits/frame=  179 fps= 12 q=31.0 size=     183kB time=00:00:14.33 bitrate= 104.5kbits/frame=  185 fps= 12 q=32.0 size=     197kB time=00:00:14.85 bitrate= 108.4kbits/frame=  191 fps= 12 q=32.0 size=     204kB time=00:00:15.36 bitrate= 108.8kbits/frame=  197 fps= 12 q=32.0 size=     209kB time=00:00:15.87 bitrate= 108.1kbits/frame=  203 fps= 12 q=32.0 size=     214kB time=00:00:16.32 bitrate= 107.5kbits/frame=  209 fps= 12 q=32.0 size=     219kB time=00:00:16.83 bitrate= 106.6kbits/frame=  215 fps= 12 q=32.0 size=     224kB time=00:00:17.34 bitrate= 105.6kbits/frame=  221 fps= 12 q=31.0 size=     225kB time=00:00:17.85 bitrate= 103.0kbits/frame=  227 fps= 12 q=30.0 size=     225kB time=00:00:18.36 bitrate= 100.2kbits/frame=  233 fps= 12 q=30.0 size=     229kB time=00:00:18.88 bitrate=  99.3kbits/frame=  239 fps= 12 q=29.0 size=     229kB time=00:00:19.39 bitrate=  96.8kbits/frame=  245 fps= 12 q=29.0 size=     230kB time=00:00:19.84 bitrate=  95.2kbits/frame=  251 fps= 12 q=29.0 size=     233kB time=00:00:20.35 bitrate=  93.7kbits/frame=  257 fps= 12 q=28.0 size=     233kB time=00:00:20.86 bitrate=  91.7kbits/frame=  263 fps= 12 q=27.0 size=     235kB time=00:00:21.37 bitrate=  89.9kbits/frame=  269 fps= 12 q=27.0 size=     240kB time=00:00:21.88 bitrate=  89.8kbits/frame=  275 fps= 12 q=27.0 size=     242kB time=00:00:22.40 bitrate=  88.4kbits/frame=  281 fps= 12 q=26.0 size=     244kB time=00:00:22.91 bitrate=  87.1kbits/frame=  287 fps= 12 q=26.0 size=     245kB time=00:00:23.36 bitrate=  86.0kbits/frame=  293 fps= 12 q=26.0 size=     253kB time=00:00:23.87 bitrate=  86.9kbits/frame=  299 fps= 12 q=26.0 size=     261kB time=00:00:24.38 bitrate=  87.7kbits/frame=  305 fps= 12 q=26.0 size=     263kB time=00:00:24.89 bitrate=  86.7kbits/frame=  311 fps= 12 q=26.0 size=     265kB time=00:00:25.40 bitrate=  85.6kbits/frame=  312 fps= 12 q=32766.0 Lsize=     386kB time=00:00:26.00 bitrate= 121.6kbits/s dup=0 drop=460
video:381kB audio:50kB subtitle:0 global headers:0kB muxing overhead -10.524577%
[libx264 @ 0x2623a60] frame I:8     Avg QP:22.06  size:  5805
[libx264 @ 0x2623a60] frame P:304   Avg QP:23.80  size:  1130
[libx264 @ 0x2623a60] mb I  I16..4: 16.7%  0.0% 83.3%
[libx264 @ 0x2623a60] mb P  I16..4:  0.8%  0.0%  1.9%  P16..4: 32.4% 16.4%  7.3%  0.0%  0.0%    skip:41.0%
[libx264 @ 0x2623a60] final ratefactor: 22.73
[libx264 @ 0x2623a60] coded y,uvDC,uvAC intra: 75.8% 79.0% 70.3% inter: 31.2% 37.7% 19.4%
[libx264 @ 0x2623a60] i16 v,h,dc,p:  4% 76%  7% 14%
[libx264 @ 0x2623a60] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 20% 24% 11%  6%  8%  8%  8%  7%  8%
[libx264 @ 0x2623a60] i8c dc,h,v,p: 33% 39% 18% 11%
[libx264 @ 0x2623a60] ref P L0: 82.0%  8.6%  9.4%
[libx264 @ 0x2623a60] kb/s:119.94
Received signal 2: terminating.