Problems with some codecs

Hello!

I am using FFMPEG for study purposes and got problems with a few codecs.
For some testing I compressed a simple image sequence
of 30 images containing numbers 0 to 29 using different codecs
and it looks as if some codecs don't handle the packets read with
av_read_frame(...) correctly. In addition I noticed that some decoding 
timestamps (DTS) occure twice for H.264...

The videos have been opened using a modified version of 
the example in "Using libavformat and libavcodec: An update"
from Martin Boehme on 
http://www.inb.uni-luebeck.de/~boehme/libavcodec_update.html.
The " DoSomethingWithTheImage(pFrameRGB);" simply displays the decoded
frame in a window and waits until a key is pressed.

The problems are as follows:

filename:               codec:          problem:
vd_h261.m1v     H.261                   packets seem to be decoded in wrong 
order,
                                                the images with numbers appear 
in an incorrect
                                                order and are heavily 
artifacted, except the first frame.
                                                Not all 30 frames are loaded 
and displayed.

vd_divx.avi     DivX                    Only every second frame is decoded and 
acknowledged by a
                                                *got_picture != 0 (no complete 
frame), but the number of packets
                                                received from av_read_frame() 
is correct (30).

vd_uncompressed.avi             everything is fine...

qt_h261.mov     H.261           Warning(h261) : first frame is no keyframe!
                                                Abort after the first packet, 
nothing decoded or displayed.

qt_h263.mov     H.263           First frame decoded and displayed correctly.
                                                Two packets loaded without 
*got_picture != 0.
                                                PTS and DTS look okay.

qt_h264.mov     H.264                   All 30 packets read, but *got_picture 
!= 0 !!!
                                                All PTS are unique (somewhere 
between 0 to 29),
                                                but most of the DTS are doubled 
(two equal in a row)...!?

qt_video.mov    QT Video (?)    everything is fine...

qt_cinepak.avi  CinePak         everything is fine...

qt_wm9.wmv                              "No suitable codec found!"


The qt_# prefix means that the video is in a quicktime container,
vd_# is .avi, .wmv or a simple .m1v file.


All files together are about 12MB in size an can be found under
http://www.ient.rwth-aachen.de/~asbach/video_test/ .

Unfortunately the server doesn't support listing, so you might
want to download them directly via "save location to..." or similar.

I would be very happy if someone can give me a useful hint,
I mean... mplayer works fine and uses FFMPEG, so what am I doing wrong...?


Best regards

Konstantin Dols
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