[Ffmpeg-devel] JPEG support in ffmpeg

[Chris Wilson]

Hi all (especially Fabrice Bellard, who I now discover is responsible for 
more than just Qemu :-)

First of all, thanks for writing ffmpeg. It looks like exactly the tool 
that I want, to assemble multiple JPEG files from a time-lapse 
sequence into a video file. Unfortunately, it doesn't work for me:

The manual page says "FFmpeg can use any supported file format and 
protocol as input". But this does not seem to be true:

chris at rocio:/tmp/ffmpeg$ ./ffmpeg -i ~/photos/raw/img_5834.jpg foo.mpg
FFmpeg version CVS, Copyright (c) 2000-2004 Fabrice Bellard
   configuration:
   libavutil version: 49.0.0
   libavcodec version: 51.9.0
   libavformat version: 50.4.0
   built on Jun  8 2006 18:29:38, gcc: 4.0.2 20050808 (prerelease) (Ubuntu 
4.0.1-4ubuntu9)
/home/chris/photos/raw/img_5834.jpg: Unknown format

chris at rocio:/tmp/ffmpeg$ ./ffmpeg -formats
FFmpeg version CVS, Copyright (c) 2000-2004 Fabrice Bellard
[...]
Image formats (filename extensions, if any, follow):
  DE jpeg   jpg,jpeg
  DE gif    gif

This is after I hacked the source to enable the line that says:

  av_register_image_format(&jpeg_image_format);

I'm surprised that JPEG is not listed as a supported file format, although 
it is listed as an image format. Perhaps that is the missing piece? Or 
else I just misunderstood the container/codec situation?

print_error() also implies that reading JPEG files should be supported:

void print_error(const char *filename, int err)
{
     switch(err) {
     case AVERROR_NUMEXPECTED:
         fprintf(stderr, "%s: Incorrect image filename syntax.\n"
                 "Use '%%d' to specify the image number:\n"
                 "  for img1.jpg, img2.jpg, ..., use 'img%%d.jpg';\n"
                 "  for img001.jpg, img002.jpg, ..., use 'img%%03d.jpg'.\n",
                 filename);
         break;

Thanks in advance for any help or advice.

Cheers, Chris.
-- 
_ ___ __     _
  / __/ / ,__(_)_  | Chris Wilson <0000 at qwirx.com> - Cambs UK |
/ (_/ ,\/ _/ /_ \ | Security/C/C++/Java/Perl/SQL/HTML Developer |
\ _/_/_/_//_/___/ | We are GNU-free your mind-and your software |