How to make high quality MPEG4 video

Sugiura Shiro sugiura at kt.rim.or.jp
Tue Sep 2 08:25:32 PDT 2003


In article <20030901201341.1e6ff86d.steve at sohara.org>
steve at sohara.org writes:

>> 	With that 2.8GHZ P4 you should be able to go direct. I can quite
>> easily record PAL 720x576 at 25fps in mpeg4 or mpeg1 on my AMD XP2000 in
>> realtime with ffmpeg alone running like this:
>> 
>> ffmpeg -s 768x576 -tvstd pal -vcodec mpeg4 -b 2000 -acodec mp3 -ac 2 \
>>   -ab 128 -f avi -t $DURATION -y $NAME.avi
>> 
>> 	It uses about 60% CPU on average, adding -hq pushes it to
>> a bit over 70%. 

Thank you.
I tried to direct encode a sportscast like following:

% ffmpeg -s 640x480 -tvstd ntsc -vcodec mpeg4 -b 2000 -acodec mp3 -ac 2 \
  -ab 128 -f avi TV.avi

It uses about 30% CPU on average.
And then, I play TV.avi using mplayer and xine. 
But output avi files seems that some frame was droped during capture 
and encode.

>> SS> Step2-2: mpeg4 encode by ffmpeg(strange out put)
>> SS> % ffmpeg -i raw.avi -vcodec mpeg4 -r 29.97 -me full -re -b 2000
>> SS> -acodec \
>> SS>   copy -deinterlace tv.avi
>> 
>> 	Strange how ?

Audio stream is OK, but Video stream playbacks 2-3X speed, like Charles
 Chaplin movies.

I tried to direct encode(mpeg1/mpeg4) and rawvideo recode , but in any case ,
my mpeg files seems that some frames was droped. I think, I  mistook 
something, but I don't know what it is.

First step, I want to know how to setup to recode/encode full frames(29.97fps)
movie.

thank you.

--  
Sugiura Shiro      E-mail : sugiura at kt.rim.or.jp


More information about the freebsd-multimedia mailing list