x264 and libavcodec

[bakel]

im still a newb on codecs :( but i realy need to use the h264 codec with libavcodec/libavformat... could anyone help me?

I can decode a mpeg2 encoded movie to ppm files. but now i want to decode h264 to some basic standard output format.

On this moment i use the function "av_register_all()" but it doesn't seem to include the h264 codec, and it includes to much codecs i dont need/want. and does someone has a nice h264 movie that is h264 encoded? because i also doubt my encode work.


thnks in advance (I gues this was correct toppic to ask this stuff)

[Doom9]

@bakel: stickies are ment as information resource, not for discussion. Please post in a separate thread next time.

x264 is not part of libavcodec so it's no surprise you can't find it.

[bakel]

Does anyone has good info for avcodec and/or avformat for beginners? I don’t mean the reference page :( I just need some learning about "how and why use what stuff" too...
especially about registering codecs manually (not all of them)

[Doom9]

I think I would start looking at ffmpeg and mencoder. Or, if you are looking into this from a VfW angle, have a look at ffdshow. On the ffmpeg page you should also find some documentation for programmers. I wouldn't know about libavformat though, afaik it's not widely used and not really ready for widespread use yet.

[bond]

Originally posted by bakel
I can decode a mpeg2 encoded movie to ppm files. but now i want to decode h264 to some basic standard output formathm i am not sure, but if i understood you right your main goal is to DEcode h.264 and not to encode it?

[bakel]

indeed... i only need to decode... I guess my program is having problems with the containers due too h264 file without container isn't excepted by my program or any codec !?!

i used http://www.inb.uni-luebeck.de/~boehme/libavcodec_update.html as underground and guessed there would be an codec that would support h264 raw input file... but that aint working :(

[bond]

why not simply leech existing compiles of ffmpeg or libavcodec.dll? :D

[bakel]

I don’t exactly what you mean but i have to make my program as small as possible that’s why I didn’t use ffmpeg... and about libavformat, I only used it because I thought I needed it, but rather lose then use it.

[bond]

i mean you could search for already existing compiles of libavcodec/libavformat when you have problems compiling it yourself

[bakel]

oh.. but those libs where compiled correctly and they work... the problem is that there is no easy documentation about them :( so I want to customize my program pure for my efforts but now have problems with the input… I only want to decode a h264 baseline video file (no sound). Now I slowly seeing more and more about it and see it should be really simple… and I still wonder if I’m the only one who’s building a h264 baseline decoder…

I guess I should be able to decode a h264 file in just 3 or 4 function calls when I use libavcodec… but without clear documentation it is very hard to learn.

[stephanV]

i tried to strip mplayer once so it would only decode MPEG4 ASP and H264... i can already tell you that the filesize gain in stripping libavcodec is not that big. The MPEG decoding seems to take up most of the space. You can comment some stuff in the makefile and i believe allcodecs.c, though (or was it avcodecs.h ... i dont really remember anymore :eek: )

If you want to optimize for filesize use upx...

[bakel]

but then again... i only need to decode (convert) i dont need any feature of ffmpeg... and i dont think its usefull to start stripping ffmpeg

[stephanV]

i was talking about libavcodec, not ffmpeg

[bakel]

but when you used that lib.. did u write your own program to use it? or did you use ffmpeg afterwards?(uppon those lib)

[stephanV]

i used mplayer with the lib yes... but, i dont think that really matters. the parts i removed were from libavcodec.

[bakel]

can someone share a h264 baseline encoded movie (+/-10 frames enough) so i know my decoder is working... i believe my encode work wasn't that good

thnks in advance

[vidhead]

thanks for the redirect =)
previous thread http://forum.doom9.org/showthread.php?p=699989#post699989

now, driven to desparation (search results for the errors i encounter were dated 2004...) i went on to test encoding x264 with virtualdubmod (latest) for 2 passes on the same vob. it worked nicely from just over 6 hours (i did throw in a few vdub filters, deinterlace-blend, resize, smoother, topped off at 3-4 FPS, the same with MeGUI on a P4 512MB hit 8-9 FPS ) for same 25-minute material [edit: MeGUI i *now* got it to run on the P4 might finish both passes in about 140 minutes].

so what caused the earlier problem? gordian knot 0.35.0 _and_ x264 encoding?

btw, as i've read it elsewhere, with ffdshow (and MPlayer+win32GUI) fi you see lots of annoying "vertical jumping/morphing/irritating artifects" turn off realtime postprocessing (deblocking) in ffdshow.

[Doom9]

fi you see lots of annoying "vertical jumping/morphing/irritating artifects" turn off realtime postprocessing (deblocking) in ffdshow.not only if... always turn it off. You don't need postprocessing for AVC content, the built-in deblocking will suffice.

[cypchen]

to Bakel:
if you want doceode h264 BASELINE, ou have a good one here:
http://www-user.tu-chemnitz.de/~mfie/stuff/SA/
it's in the stick, i've tested it

also, can you share you Main Programme using Libavcodec? i'm interested.

thx