[MPlayer-users] y4mscaler in encode2mpeg

[romildo at uber.com.br]

Hello.

Yesterday I have sugested (see below) the inclusion
of y4mscaler as an optional scaler in the encode2mpeg
program:

   http://encode2mpeg.sourceforge.net/encode2mpeg.html

   encode2mpeg is a front end to MPlayer/MEncoder and
   mjpegtools. It is able to convert any kind of video
   that mplayer can play in a format suitable for
   VCD/SVCD/DVD, plus it can create DivX avi.

Then it was asked what improvements y4mscaler would
bring when compared with the BICUBIC scaler of
yuvscaler (see below again).

As I am not prepared to give such explanation, I am
forwarding the message to the mjpeg-users mailing
list so that someone with more knowledge of the
subject could provide an explanation.

Reference:
http://mplayerhq.hu/pipermail/mplayer-users/2005-February/051208.html

Regards.

Romildo

-----

On Tue, Feb 01, 2005 at 09:33:25PM -0200, romildo at uber.com.br wrote:
> 
> Let me sugest to the author of encode2mpeg the
> use of y4mscaler as an optional scaler for the
> mpeg stream.
> 
> Its home page is
> http://www.mir.com/DMG/Software/y4mscaler.html
> 
> It is a very good video scaler which operates on
> YUV4MPEG2 streams, as used by the tools in the
> MJPEGtools project. 
> 
> y4mscaler and yuvscaler are compared in a thread
> in the mjpeg-users mailing list:
> http://sourceforge.net/mailarchive/message.php?msg_id=6883437

I have checked quickly the home page of y4mscaler
and the thread in the mjpeg-users mailing list.

The only reason I see to use y4mscaler instead of yuvscaler
would be because y4mscaler has more scaling engines.

Is it just that or did I miss something?

My question is: how much better it would be to use a better
scaler of y4mscaler compared with
the BICUBIC scaler of yuvscaler? And how can I measure the
improvement?
(With MEncoder I can test different scalers and check the
PSNR for the best result).

If you need many kind of sowtware scalers you can already use
Mpeg Mode and choose between the 10 scalers of mencoder.

Giacomo