[FFmpeg-trac] #692(undetermined:new): Audio is not in sync with video, webcam capturing
FFmpeg
trac at avcodec.org
Mon Nov 28 03:13:42 CET 2011
#692: Audio is not in sync with video, webcam capturing
-------------------------------------+-------------------------------------
Reporter: burek | Owner:
Type: defect | Status: new
Priority: important | Component:
Version: git-master | undetermined
Keywords: | Resolution:
Blocking: | Blocked By:
Analyzed by developer: 0 | Reproduced by developer: 0
-------------------------------------+-------------------------------------
Comment (by burek):
There were no errors in the output, that's why I didn't provide it, so
here it is:
{{{
# ffmpeg -f video4linux2 -r 25 -s vga -i /dev/video0 -f alsa -ar 44100 -ac
1 -i front:CARD=U0x46d0x809,DEV=0 -isync -vcodec libx264 -preset fast$
ffmpeg version N-35149-g3880b45, Copyright (c) 2000-2011 the FFmpeg
developers
built on Nov 25 2011 02:16:49 with gcc 4.6.2
configuration: --enable-static --enable-shared --enable-gpl --enable-
nonfree --enable-postproc --enable-libx264 --enable-libaacplus --enable-
libmp3lame --$
libavutil 51. 28. 0 / 51. 28. 0
libavcodec 53. 37. 0 / 53. 37. 0
libavformat 53. 21. 0 / 53. 21. 0
libavdevice 53. 4. 0 / 53. 4. 0
libavfilter 2. 49. 0 / 2. 49. 0
libswscale 2. 1. 0 / 2. 1. 0
libpostproc 51. 2. 0 / 51. 2. 0
[video4linux2,v4l2 @ 0x124ca20] Estimating duration from bitrate, this may
be inaccurate
Input #0, video4linux2,v4l2, from '/dev/video0':
Duration: N/A, start: 865.119708, bitrate: 92160 kb/s
Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 640x480,
92160 kb/s, 25 tbr, 1000k tbn, 25 tbc
[alsa @ 0x124da00] Estimating duration from bitrate, this may be
inaccurate
Input #1, alsa, from 'front:CARD=U0x46d0x809,DEV=0':
Duration: N/A, start: 1322445758.231273, bitrate: N/A
Stream #1:0: Audio: pcm_s16le, 48000 Hz, 1 channels, s16, 768 kb/s
[buffer @ 0x124f040] w:640 h:480 pixfmt:yuv420p tb:1/1000000 sar:0/1
sws_param:
[libx264 @ 0x1247580] using cpu capabilities: MMX2 SSE2Fast SSSE3 Cache64
[libx264 @ 0x1247580] profile High, level 3.0
[mpegts @ 0x1247040] muxrate VBR, pcr every 2 pkts, sdt every 200, pat/pmt
every 40 pkts
Output #0, mpegts, to 'udp://burek:10001':
Metadata:
encoder : Lavf53.21.0
Stream #0:0: Video: h264, yuv420p, 640x480, q=-1--1, 90k tbn, 25 tbc
Stream #0:1: Audio: aac, 48000 Hz, 1 channels, s16, 32 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (rawvideo -> libx264)
Stream #1:0 -> #0:1 (pcm_s16le -> libaacplus)
Press [q] to stop, [?] for help
frame= 373 fps= 24 q=25.0 Lsize= 2648kB time=00:00:14.46
bitrate=1499.7kbits/s dup=155 drop=0
video:2350kB audio:59kB global headers:0kB muxing overhead 9.917098%
[libx264 @ 0x1247580] frame I:2 Avg QP:17.79 size: 23828
[libx264 @ 0x1247580] frame P:306 Avg QP:19.51 size: 6459
[libx264 @ 0x1247580] frame B:65 Avg QP:21.62 size: 5883
[libx264 @ 0x1247580] consecutive B-frames: 66.5% 30.6% 0.8% 2.1%
[libx264 @ 0x1247580] mb I I16..4: 9.5% 78.3% 12.2%
[libx264 @ 0x1247580] mb P I16..4: 0.1% 0.9% 0.1% P16..4: 39.7% 14.0%
7.2% 0.0% 0.0% skip:38.0%
[libx264 @ 0x1247580] mb B I16..4: 19.8% 19.3% 0.0% B16..8: 9.2% 1.2%
0.0% direct:31.1% skip:19.5% L0:40.8% L1:48.1% BI:11.1%
[libx264 @ 0x1247580] 8x8 transform intra:54.9% inter:75.2%
[libx264 @ 0x1247580] coded y,uvDC,uvAC intra: 36.2% 100.0% 98.6% inter:
24.4% 57.2% 43.1%
[libx264 @ 0x1247580] i16 v,h,dc,p: 43% 19% 22% 15%
[libx264 @ 0x1247580] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 15% 40% 5% 4%
4% 4% 5% 5%
[libx264 @ 0x1247580] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 24% 25% 14% 7% 6%
5% 6% 5% 7%
[libx264 @ 0x1247580] i8c dc,h,v,p: 61% 21% 11% 7%
[libx264 @ 0x1247580] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x1247580] ref P L0: 75.1% 24.9%
[libx264 @ 0x1247580] ref B L0: 75.4% 24.6%
[libx264 @ 0x1247580] kb/s:1290.40
#
}}}
I always had problems with syncing audio and video with ffmpeg and webcam
capturing, so I believe this might not be a regression.
--
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/692#comment:2>
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