[Ffmpeg-devel] Decoding images (jpeg) from an url

[Stefan Lucke]

On Dienstag, 20. September 2005 10:43, Michel Bardiaux wrote:
> Stefan Lucke wrote:
> > On Montag, 19. September 2005 15:00, Michel Bardiaux wrote:
> > 
> >>Stefan Lucke wrote:

> >>>FfmpegIO: url(http://w.x.y.z:9001/disk/photo/O2385(1536x1024,0).jpg) is NOT playable (nil) (rc = -6)
> >>>
> >>>It works fine for mp3 urls and with stuttering audio and video for vdr files.
> >>>FfmpegIO: url(http://w.x.y.z:9001/disk/music/O562.mp3) is playable 0x87a51c0 (rc = 0)
> >>>FfmpegIO: url(http://w.x.y.z:9001/disk/video/O4712.vdr) is playable 0x8720de0 (rc = 0)
> >>>
> >>>Would be nice if some could give me a hint how to proceed.
> >>>
> >>>
> >>
> >>Since we cat access the URLs in question, and anyway the program as 
> >>published is incomplete, I can only suggest you look in the source the 
> >>reasons why av_open_input_file can return -6.
> >>
> > 
> > 
> > I think its the same as I get when calling ffmpeg:
> > stefan at jarada:~> ffmpeg -i 'http://w.x.y.z:9001/disk/photo/O2385(1536x1024,0).jpg' x.yuv
> > ffmpeg version CVS, build 3276800, Copyright (c) 2000-2004 Fabrice Bellard
> >   configuration:  --enable-shared --enable-pp --enable-shared-pp --enable-gpl --enable-a52
> >   built on Sep 17 2005 13:23:03, gcc: 3.3.1 (SuSE Linux)
> > http://w.x.y.z:9001/disk/photo/O2385(1536x1024,0).jpg: Unknown format
> 
> Good idea. Now we know your software is probably not to blame.
> 
> > 
> > (real ip adresses replaced).
> > 
> What happens if you try with some JPEG on the web at some URL anyone can 
> access? (I could try that myself but you wisely asked for *hints*...)

stefan at jarada:~> ffmpeg -i 'http://softdevice.berlios.de/vdr-1.3.7-vidix-radeon-alpha-screenshot-small.jpg' x.yuv
ffmpeg version CVS, build 3276800, Copyright (c) 2000-2004 Fabrice Bellard
  configuration:  --enable-shared --enable-pp --enable-shared-pp --enable-gpl --enable-a52
  built on Sep 17 2005 13:23:03, gcc: 3.3.1 (SuSE Linux)
http://softdevice.berlios.de/vdr-1.3.7-vidix-radeon-alpha-screenshot-small.jpg: Unknown format

stefan at jarada:~> ffmpeg -i 'http://softdevice.berlios.de/vdr-1.3.7-xv-screenshot-small.png' x.yuv
ffmpeg version CVS, build 3276800, Copyright (c) 2000-2004 Fabrice Bellard
  configuration:  --enable-shared --enable-pp --enable-shared-pp --enable-gpl --enable-a52
  built on Sep 17 2005 13:23:03, gcc: 3.3.1 (SuSE Linux)
http://softdevice.berlios.de/vdr-1.3.7-xv-screenshot-small.png: Unknown format

As that shows the same return code for different picture formats, I'll
guess there is something wrong in my expectation that av_open_input_file()
could be used as a generic approach for guessing required codec for a given
input source.

-- 
Stefan Lucke