[MPlayer-users] encode2mpeg xvid/ac3 to svcd

[Giacomo Comes]

On Mon, Nov 29, 2004 at 04:43:43PM -0500, Erick Perez wrote:
> Hi, while converting a movie to SVCD i got my audio out of sync and
> the video is somehow weird. Here is what i did:
> (I want to view the output on a normal dvd player not in a computer dvd player.)
> Thanks for your time. This will help to understand some other things ....
> 
> [eperez at fedora]$ tcprobe -i theforgo2.avi
> [tcprobe] RIFF data, AVI video
> [avilib] V: 25.000 fps, codec=XVID, frames=58332, width=608, height=352
> [avilib] A: 48000 Hz, format=0x2000, bits=0, channels=6, bitrate=448 kbps,
> [avilib]    58321 chunks, 130663680 bytes, CBR
> [tcprobe] summary for theforgo2.avi, (*) = not default, 0 = not detected
> import frame size: -g 608x352 [720x576] (*)
>        frame rate: -f 25.000 [25.000] frc=3
>       audio track: -a 0 [0] -e 48000,0,6 [48000,16,2] -n 0x2000 [0x2000] (*)
>                    bitrate=448 kbps
>            length: 58332 frames, frame_time=40 msec, duration=0:38:53.280
> 
> The movie is in PAL format and want to change it to NTSC
> 
> encode2mpeg 0.3.0
> 
>  encode2mpeg theforgo2.avi  -n p -usesbr 3 -ac3 copy -nosplit
> -mpegonly -o theforgo2 -svcd
> 
> BTW do i need to rescale or can i -noscale?
> 
> Suggestions?

encode2mpeg theforgo2.avi  -n p -usesbr 3 -ac3 copy -nosplit
  -mpegonly -o theforgo2 -svcd

Hi,
I will try to explain your doubt. It's also good for me to
understand what is not clear in the documentation :-).

Remember there are 4 operating mode for encode2mpeg:
1) DivX mode (mpeg4 avi)
2) direct mode (mpeg1/2 with mpeg2enc)
3) indirect mode (DivX avi + mpeg1/2 with mpeg2enc)
4) mpeg mode (mpeg1/2 with mencoder)

Your command line is using Direct mode
(I think I will put in the log file which mode is active)

You have a PAL video and want an NTSC video.
You cannot use direct mode. The audio will go out of sync for sure.
You can use indirect mode or mpeg mode.

Add -n n (you want NTSC)
You need to rescale because NTSC SVCD is 480x480 then no -noscale,
add -a 3 (your video has a aspect ratio of 1.73, close to 16/9)
(The video will be a little bit distorted because the original
aspect ratio is not exactly 16/9. I'm working on this problem
and I want to include an option to automatically adapt the aspect
ratio. At the moment I'm stuck with an expand filter bug of 
mplayer. I reported the bug to the list, but got no answer :-(. )

Now let's talk about -usesbr 3. First: it does nothing in mpeg mode.
It is not in the list of options in the html page of direct mode.
It works in DivX mode and mpeg mode. In indirect mode it will set 
the size of the avi file not the mpeg.
Most importantr: it doesn't make sense to use that options for a SVCD.
The SVCD is 480x480 mpeg2. Usually a SVCD can contain 45-60 minutes
of video. A 2 hours movie wont fit on a SVCD. If you squeeze it to 
800 MB the quality will be poor. Better to use a VCD.
(eventually with mpeg1vbr and/or kvcd qmatrix)

To resume I suggest you to try with:

encode2mpeg theforgo2.avi -n n -ac3 copy -mpegonly -o theforgo2 -svcd -encode 0:2:2 -a 3
(indirect mode)
if the video is "weird" add
	-toolopts mpeg2enc -q 4
at the end of the command line. Values between 2 and 7 should improve
the video quality (and increase the file size).

or 

encode2mpeg theforgo2.avi -n n -ac3 copy -mpegonly -o theforgo2 -svcd -encode 0:2:2 -a 3 -mpeg
(mpeg mode)
You can also add -usesbr 3 and compare the video quality with and without -usesbr.

I recommend you to download encode2mpeg 0.3.1.
It is more accurate when splitting the mpeg file in direct/indirect mode.

Giacomo