[theora] Accelerated video output with ffmpeg2theora 0.24

[Juhani Jaakola]

I don't know why the framerate of the input file is 25.02. The input file is produced by Ulead Video Studio, which captures video from VHS tapes (PAL format) via an USB frame grabber. It produces .AVI files. The frame rate of PAL is 25 fps.

When I convert those .AVI files to H.264/AAC or to xvid/MP3 with Avidemux, they play without problems. It is only the ffmpeg2theora which causes problems. And I have problems with ffmpeg2theora with and without those parameters (see my original message).

Regards, JJ

j at v2v.cc kirjoitti: 
> Juhani Jaakola wrote:
> > Does anybody have a clue what might be the problem here?
> > 
> > On 09/06/2009 01:00 PM, Juhani Jaakola wrote:
> >> When I converted two files with ffmpeg2theora their duration changed shorter - they seem to play back with accelerated speed. When I play one of them with VLC, the video stops at 99 seconds but audio continues until 170 seconds. The other file is 120 seconds long but it is played back in 80 seconds.
> >>
> >> Here is ffmpeg2theora output:
> >>
> >> $ ffmpeg2theora --optimize --inputfps 25 -F 25 2002-05-23\ Juho\ prinssina.AVI
> >> Input #0, avi, from '2002-05-23 Juho prinssina.AVI':
> >>    Duration: 00:02:36.76, start: 0.000000, bitrate: 107321 kb/s
> >>      Stream #0.0: Video: rawvideo, yuyv422, 720x576, 25 tbr, 25 tbn, 25 tbc
> >>      Stream #0.1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
> >>    Resize: 720x576
> >>        0:02:36.76 audio: 78kbps video: 8080kbps, time elapsed: 00:13:26
> >>
> >> $ ffmpeg2theora --inputfps 25 -F 25 196X\ Juhani\ pienenä\ LAAJEMPI\ VERSIO.AVI
> >> Input #0, avi, from '196X Juhani pienenä LAAJEMPI VERSIO.AVI':
> >>    Duration: 00:01:59.59, start: 0.000000, bitrate: 109973 kb/s
> >>      Stream #0.0: Video: rawvideo, yuyv422, 720x576, 25.02 tbr, 25.02 tbn, 25.02 tbc
> >>    Resize: 720x576
> >>        0:01:19.31 audio: 0kbps video: 5449kbps, time remaining: 00:04:19
> >>
> why does the input file have a framerate of 25.02? forcing input
> framerate might not work, it was mostly used for video4linux devices.
> but can have a look in the source to see if it can be extended to also
> overwrite the framerate from the input container.
> 
> 
> j
>