[Kdenlive-devel] A/V out of sync rending AVCHD source to anything

[Paul Hartman]

Hi,

I have Canon AVCHD source footage from my camcorder, and am having
trouble keeping A/V sync in Kdenlive. With no effects, but changing
the starting point of the clip to about 5 minutes in, sync is off a
little. Applying effects causes sync to become worse. It is out of
sync both in the project preview and in rendered videos. I'm using
latest svn/csv/git versions of x264/ffmpeg/mlt/kdenlive. (When using
"ffplay" to play and seek around the source file, the sync remains
good.) The sound happens before the video (I hear words, then I see
mouth moving).

Are there any tricks, like converting to another container format,
transcoding into another type, something that's more friendly to keep
the sync in check in kdenlive? Thanks.

I'm using HDV 1440x1080 60i profile. The sync problems don't seem to
be affected by render target (since it happens even in the preview
window)

here is ffmpeg -i for the source file:

FFmpeg version SVN-r20717, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  built on Dec  3 2009 11:10:30 with gcc 4.4.2
  configuration: --prefix=/usr --libdir=/usr/lib64
--shlibdir=/usr/lib64 --mandir=/usr/share/man --enable-static
--enable-shared --cc=x86_64-pc-linux-gnu-gcc --disable-debug
--disable-ipv6 --enable-libmp3lame --enable-libvorbis
--enable-libtheora --enable-libx264 --enable-libxvid
--enable-libdc1394 --disable-indev=oss --disable-indev=jack
--disable-outdev=oss --enable-x11grab --enable-pthreads
--enable-libfaad --enable-libspeex --enable-libopenjpeg
--enable-libgsm --enable-libfaac --enable-nonfree --disable-altivec
--disable-amd3dnow --cpu=host --enable-gpl --enable-version3
--enable-postproc --enable-avfilter --enable-avfilter-lavf
--disable-stripping --enable-hardcoded-tables --disable-doc
  libavutil     50. 5. 1 / 50. 5. 1
  libavcodec    52.42. 0 / 52.42. 0
  libavformat   52.40. 0 / 52.40. 0
  libavdevice   52. 2. 0 / 52. 2. 0
  libavfilter    1.11. 0 /  1.11. 0
  libswscale     0. 7. 2 /  0. 7. 2
  libpostproc   51. 2. 0 / 51. 2. 0
[mpegts @ 0x16fd3c0]MAX_READ_SIZE:5000000 reached
Input #0, mpegts, from 'wedding1.mts':
  Duration: 00:46:07.29, start: 0.767000, bitrate: 15883 kb/s
  Program 1
    Stream #0.0[0x1011]: Video: h264, yuv420p, 1440x1080 [PAR 4:3 DAR
16:9], 59.94 tbr, 90k tbn, 59.94 tbc
    Stream #0.1[0x1100]: Audio: ac3, 48000 Hz, stereo, s16, 256 kb/s
At least one output file must be specified