H264 playback problem

[qyqgpower]

I encoded a movie using x264, here is the 2nd pass command line

"x264.exe" --pass 2 --bitrate 1500 --stats "2pass.log" --ref 6 --bframes 2 --b-pyramid --weightb --analyse p8x8,b8x8,i4x4,p4x4 --qpmax 24

output is set to mkv and i mux it with an ac3(448kbps 5.1ch) file into a new mkv. playing the file in mpc (decoder is ffdshow's h264) just results slow motion, the fps is only about 20 (it should be 23.976), and of course it isn't sync with audio. I trid mplayer, it says "your system is too SLOW to play this!" and get the speed of 0.5fps, then crashed by "[h264 @ 009E3CB8]illegal short term buffer state detected".

the video size is 768 x 432. I tried another downloaded avc movie(848 x 480) and get no problem, so i think my pc is fast enough to decode avc movie.so what caused the problem? too many ref? b-pyramid?

[stephanV]

can you play the file before muxing? what muxing app are you using (and is it up to date)?

[qyqgpower]

i'm using mkvtoolnix-unicode-1.5.6, and it's the newest.
i had used 1.5.4 and would mux into a unseekable mkv(seek the file results the crash of mpc).

here i want to ask another question, how to extract the avc track from mkv? i use mkvextract and only get a unplayable file.

[stephanV]

You didnt answer my first question...

MKVExtract extracts to raw h264. you should be able to play it in a recent build of mplayer.