Re: [Mjpeg-users] mplex not recognizing mpeg1 from mencoder

[Steven M. S. <sm...@2B...>]

On Sat, 3 Jan 2004 ro...@ub... wrote:

> I do not think 1.6.1.92 is that old. If I am not wronk, it has been
> released by the end of November.

	Maybe it just _feels_ old ;)   Seems that the next release candidate
	has been "real soon now" for a long time.

> spead things up. I have been using them. I have also been using
> the "-E n" with n being a value between -15 and -4, in order
> to get smaller files. Do you think this is a good idea?

	Definitely a good idea.    Values in the -10 range are quite
	conservative (I tend to use either -8 or -10).

> It seems that the small (in absolute value) values for n
> dos not affect the quality that much.

	Very true - the visual quality is not reduced but the size of the
	file is smaller (sometimes considerably smaller).

> What does change in CVD compared to SVCD encoding? Only the frame size?

	The only thing that changes is the encoded frame size.   SVCDs
	use a coded frame size of 480x480 which is expanded on playback
	to 640x480 (4/3) or 854x480 (16/9) (and yes, 16/9 is valid for SVCDs
	but the hardware players I've tried do not know about it).

	CVDs are encoded at 352x480 (which is also a valid DVD size) and
	get expanded to 640x480 or 854x480 on playback.   

> a frame size of 672x504. Then I resize it to 480x480 and set the
> aspect ratio to 4:3. What would be the procedure for a CVD target
> in this example?

	If you're using 'y4mscaler' to do the scaling then all you need to
	do is change the "-O preset=SVCD" to "-O preset=CVD" and it will
	perform the necessary magic for you. 

	Cheers,
	Steven Schultz