[FFmpeg-trac] #5526(ffmpeg:new): Frame drop log constantly when rtmp live encoding

FFmpeg trac at avcodec.org
Mon May 9 16:29:21 CEST 2016

#5526: Frame drop log constantly when rtmp live encoding
             Reporter:  kgp700  |                     Type:  defect
               Status:  new     |                 Priority:  normal
            Component:  ffmpeg  |                  Version:  git-master
             Keywords:          |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
 Summary of the bug:

 Frame drop log appear constantly when rtmp live encoding
 This problem occur when do not specify input framerate on ffmpeg

 Input source :
 Video : FFSplit (Capture region - Live Screen capture)
 Input Video FPS : 30fps
 Audio : Creative X-FI Xtreme Music : What U Hear (Stereo Mix)

 but It log seems to be wrong.. Actually I can't see frame drop on video

 If occur this problem, increase framedrop log constantly
 like this : increase framedrop count log per 3sec or 10sec...
 It's constantly increase

 When I seen the logfile, '''I found some two weird things'''
 '''1. Output framerate not constant
 '''Sometimes Output framerate is 29.92fps or 29.83fps...
 If normal situation, It must be always 30fps

 On the Old ffmpeg build (Build at 9/April), always 30fps

 '''2.Input tbr is not constant'''
 I found input video's tbr will be output video framerate
 On the Old ffmpeg build (9,April), input video's tbr was always 30tbr

 but not on recenty ffmpeg build (9,May)
 tbr randomly change to 29.92tbr or 29.83tbr...

 My current ffmpeg git commit is 5fce4753ff0f9e4ebada3fa3619e0cf0b639385d

 Please fix it

 How to reproduce:
 % ffmpeg.exe -y -rtbufsize 2000M -f dshow -audio_buffer_size 65 -i
 -883F-D2F5AB95D3FD}" -pix_fmt yuv420p -filter_complex
 -vcodec libx264 -preset faster -profile:v high -crf 17 -g 120 -x264opts
 :aq-strength=0.8:b-adapt=1:scenecut=45:keyint-min=60 -aspect 1152/648
 -bufsize:v 1780k -maxrate:v 1780k -report -map 0 -acodec libfdk_aac -b:a
 224k -ar 48000 -map_metadata -1 -map_chapters -1
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.

Ticket URL: <https://trac.ffmpeg.org/ticket/5526>
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