I wrote:
> I eventually enabled some debug output in avidec.c in libavformat and
> used that together with strace to narrow down the problem.
> avi_read_seek() seeks to the correct position but then
> avi_read_packet(), having detected that the position is beyond the
> declared file length, seeks again. I cannot see what the purpose of
> this seek is, and removing it fixes the problem for me:
>
> --- ffmpeg-0.cvs20060329.orig/libavformat/avidec.c
> +++ ffmpeg-0.cvs20060329/libavformat/avidec.c
> @@ -594,7 +594,6 @@
>
> if (i >= avi->movi_end) {
> if (avi->is_odml) {
> - url_fskip(pb, avi->riff_end - i);
> avi->riff_end = avi->movi_end = url_fsize(pb);
> } else
> break;
> -- END --
After some further experimentation with the above change, I believe the
seek is necessary when reading past the first DML index (rather than
starting beyond it). This change seems to result in correct behaviour
in both cases:
--- ffmpeg-0.cvs20060329.orig/libavformat/avidec.c
+++ ffmpeg-0.cvs20060329/libavformat/avidec.c
@@ -594,7 +594,8 @@
if (i >= avi->movi_end) {
if (avi->is_odml) {
- url_fskip(pb, avi->riff_end - i);
+ if (i < avi->riff_end)
+ url_fskip(pb, avi->riff_end - i);
avi->riff_end = avi->movi_end = url_fsize(pb);
} else
break;
-- END --
Ben.
--
Ben Hutchings -- [EMAIL PROTECTED] shortened to [EMAIL PROTECTED]
If you've signed my GPG key, please send a signature on and to the new uid.
Time is nature's way of making sure that everything doesn't happen at once.
signature.asc
Description: This is a digitally signed message part
