I want to convert DAV format video clips from CCTV recorders to AVI using command as below (convert test - 1.dav to test - 1.avi)

ffmpeg -y -i test\ -\ 1.dav -vcodec copy -movflags +faststart test\ -\ 1.avi

It works properly on x86_64 Linux with ffmpeg ver 2.4.13 and Synology with ffmpeg ver 2.0.2. File after converting is fully playable on Windows, Android, iPad and Linux. But when I try to convert it on Synology equipped with the newest version of software, then fails (ffmpeg ver 2.7.1). Below output from conversion process:

ffmpeg version 2.7.1 Copyright (c) 2000-2015 the FFmpeg developers
built with gcc 4.9.3 (crosstool-NG 1.20.0) 20150311 (prerelease)
configuration: --prefix=/usr --incdir='${prefix}/include/ffmpeg' --arch=arm --target-os=linux --cross-prefix=/usr/local/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi- --enable-cross-compile --enable-optimizations --enable-pic --enable-gpl --enable-shared --disable-static --enable-version3 --enable-nonfree --enable-libfaac --enable-encoders --enable-pthreads --disable-bzlib --disable-protocol=rtp --disable-muxer=image2 --disable-muxer=image2pipe --disable-swscale-alpha --disable-ffserver --disable-ffplay --disable-devices --disable-bzlib --disable-altivec --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libmp3lame --disable-vaapi --disable-decoder=amrnb --disable-encoder=zmbv --disable-encoder=dca --disable-encoder=ac3 --disable-encoder=ac3_fixed --disable-encoder=eac3 --disable-decoder=dca --disable-decoder=eac3 --disable-decoder=truehd --cc=/usr/local/arm-unknown-linux-gnueabi/bin/arm-unknown-linux-gnueabi-ccache-gcc
libavutil      54. 27.100 / 54. 27.100
libavcodec     56. 41.100 / 56. 41.100
libavformat    56. 36.100 / 56. 36.100
libavdevice    56.  4.100 / 56.  4.100
libavfilter     5. 16.101 /  5. 16.101
libswscale      3.  1.101 /  3.  1.101
libswresample   1.  2.100 /  1.  2.100
libpostproc    53.  3.100 / 53.  3.100
Input #0, h264, from 'test - 1.dav':
Duration: N/A, bitrate: N/A
Stream #0:0: Video: h264 (Main), yuv420p, 704x576, 25 fps, 25 tbr, 1200k tbn, 50 tbc
Output #0, avi, to 'test - 1.avi':
ISFT            : Lavf56.36.100
Stream #0:0: Video: h264 (H264 / 0x34363248), yuv420p, 704x576, q=2-31, 25 fps, 25 tbr, 50 tbn, 50 tbc
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[avi @ 0xb0ff0] H.264 bitstream malformed, no startcode found, use the video bitstream filter 'h264_mp4toannexb' to fix it ('-bsf:v h264_mp4toannexb' option with ffmpeg)
av_interleaved_write_frame(): Invalid data found when processing input
frame=    1 fps=0.0 q=-1.0 Lsize=       6kB time=00:00:00.02 bitrate=2300.0kbits/s    
video:40kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Conversion failed!

I have to mention that in each case, I use the same input file and the same ffmpeg syntax for conversion. The only differences are versions of ffmpeg. What is most strange, the newest version works wrong. What mistake/error I am doing? Any idea?


Newer ffmpeg version refuses to mux H.264 encoded video without startcodes to AVI. You should use -bsf:v h264_mp4toannexb as it is indicated in ffmpeg output. This will not reencode your video.

  • But the problem is that after conversion with -bsf:v h264_mp4toannexb option, first 2-3 sek of move (for example walking man) are very fast in display (using VLC or other player) and after 2-3 sek, movement are "ordinary" in speed. Is any possibility to correct it?
    – mackowiakp
    Sep 30 '16 at 9:11
  • Does ffmpeg produce any warnings? You can try add -fflags +genpts or play with -copyts/-copytb/-start_at_zero options. I can not find more without video sample. Sep 30 '16 at 9:21
  • 1
    BTW, -movflags +faststart seems useless in your command, because this option is for mp4 muxer only. Sep 30 '16 at 9:22
  • OK. Now I use syntax find ./ -type f -mmin +10 -name "*.dav" -exec ffmpeg -y -i {} -bsf:v h264_mp4toannexb -fflags +genpts {}.avi \;
    – mackowiakp
    Sep 30 '16 at 11:45
  • If You want to test, take sample clip from my Dropbox. Link https://dl.dropboxusercontent.com/u/79280403/test.dav
    – mackowiakp
    Sep 30 '16 at 11:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.