[Ffmpeg-devel] mpeg4 file container

[hannes]

hi!
i have noticed that mp4 files created with ffmpeg build after february have
problem playing in some players.
I use ffmpeg -i 123.avi -vcodec mpeg4 -b 448 -acodec aac -ab 64 -f mp4 123.mp4
for encoding.
the files convert just fine, but there is something that prevents the files
beeing played back. i had a look at the headers and noticed that the new ones
that dont play contain "   ftypisom   mp41   wide ??mdat?  libfaac 1.24"
while the old working ones would start with "   ftypisom   mp41 ?gmdat? 
libfaac 1.24". i couldnt find any differences when looking at the files with
file information tools like mediainfo.exe
the files play fine in vlc and quicktime, they dont play in pvplayer or
nintendo's play-yan.
i used the builds i could find at http://ffdshow.faireal.net/mirror/ffmpeg/
i uploaded everything to:
www.formaji.com/old.exe -> ffmpeg downloaded ~february
www.formaji.com/new.exe -> march ffmpeg, newer ones have the same problem
www.formaji.com/old.mp4 -> old ffmpeg converted file
www.formaji.com/new.mp4 -> you get it

can someone give me a clue what was changed in the code? why do the converted
files differ?

also i tried compiling ffmpeg yesterday myself and it doesnt seem to work. at
some point it allways gives me an error 1 and stops compiling, no matter what
./configuration i use. others experienced this?

thanks
hannes