ColorMatrix v2.3

[Wilbert]

ColorMatrix corrects the colors of mpeg2 streams of dvds. More correctly, those mpeg2 streams are encoded using a different set of coefficients as used by AviSynth's color conversion routines or by the XviD/DivX decoders, with the result that DivX/XviD clips or mpeg2 clips encoded by TMPGEnc/CCE using AviSynth or VirtualDub are displayed with slighty off colors (which looks like a small difference in brightness[*]). This can be checked by opening the mpeg2 stream directly in VDubMod. More info can be found in the readme.

This filter recalculates the yuv values assuming the coefficients which are used by AviSynth/VDub/DivX/XviD, with the consequence that your final encoding (mpeg2 or mpeg4) is displayed correctly.
[*] http://forum.doom9.org/showthread.ph...595#post514595

Changelog v2.3 (by tritical),

- Calculate conversion coefficients for PB/PR rows from luma coefficients
- Added inputFR and outputFR parameters allowing for YUV range expansion/contraction
- Changed the clamp parameter from bool to int to allow specifying only pre clipping or only post clipping or both

more info: http://forum.doom9.org/showthread.ph...227#post887227

http://web.missouri.edu/~kes25c/

[malkion]

Wilbert, if this filter does indeed perform as you intended it, I would like to express some gratitude for future encodes....

Now should I run limiter() before or after colormatrix() ?

[Teegedeck]

I've waited for this a long time! If only I had time right now to try it out...

A heartfelt 'thank you'.

[Boulder]

Thanks, this one will be very useful!

[Wilbert]

Now should I run limiter() before or after colormatrix() ?

If you get v1.1, you don't need to use limiter at all (not before or after the filter). The filter clamps input to [16,235] (and output also).

[sh0dan]

Made a few (easy) speedups - it should be a couple of times faster now.

Updated source.

- Use float instead of double. They have enough precision and are much faster. It can however be changed back by changing the typedef in ColorMatrix.h

- Simpler algorithms.

- Use internal limiter for output also, instead of very slow if-then.

- Better rounding (adding 0.5 for more exact float to int conversion)

No SSE/MMX this tim, though.

thank you very much Wilbert !

i was "stuck inside a cloud" here trying to find a way for that problems!
now our encodes will get much, much more quality !

downloading and testing!

[Wilbert]

@Sh0dan,

Thanks! I updated the version.

[Inc]

Thanks a lot Wilbert !

Originally posted by Wilbert
@Sh0dan,

Thanks! I updated the version.

of course....

thank you too Sh0dan.

.seems that we posted at the same time and i saw your post after my last!

[Dark-Cracker]

very nice work
just by curiosity does it will harm the final output if u apply this filter on HDTV source or on some raw avi input ?

++

[Wilbert]

just by curiosity does it will harm the final output if u apply this filter on HDTV source

I got a few hdtv sources. Marjority of them uses mpeg2 coefficients (checked with the newest GSpot). So, you should also use the filter on those sources.

However, a few of them uses mpeg1 coefficients. You shouldn't apply the filter on those.

on some raw avi input

Here, you shouldn't use this filter. DivX/XviD assume mpeg1 coefficients when decoding to RGB.

edit: btw, hdtv is YUV [0,255] of course. So you need to use ColorYUV("PC->TV") first.

[FuPP]

I have a question about colormatrix and speed. I use colormatrix() 1.2 and get the following results

with colormatrix : 16.5 fps
without colormatrix : 44.5 fps

should such a difference be expected or is there any problem ?

My script (source is 720x576) :

LoadPlugin("D:\video\avsfilters\yv12\DGDecode.dll")
LoadPlugin("D:\video\avsfilters\yv12\colormatrix.dll")

mpeg2source("d:\test\test.d2v",idct=6)

trim(30000,33000)
colormatrix()

FuPP

[Wilbert]

The problem is that the filter is not optimized. Since I'm not a good coder, I don't know how to do that. I hope someone has some time to do that

[Manao]

I added other easy optimisations ( no more float computations, only integer one ). Results *should* be the same as those given by sh0dan's version. It should be almost twice as fast.

http://jourdan.madism.org/~manao/ColorMatrix.zip

[Wilbert]

Thanks! Could you also add the correct source files?

[Manao]

I copy'n'pasted the wrong files

You can download it again.

[Wilbert]

Thanks, I added it to the first post! I didn't have time to test it though

[FuPP]

with colormatrix : 34.5 fps
without colormatrix : 44.5 fps

Far better ! Thanks a lot Manao ! And thanks a lot Wilbert for that filter

FuPP

[ltc]

How to properly use this filter?
Say if I want to re-encode a DVD to DVD-R for TV playing. I assume I should use YUV and TV scale in DVD2AVI. I can find the original matrix coefficient with GSpot which has following type:

I709 = type 1 = MPEG2 default
FCC = type 4 = FCC standard
I470 = type 5 = MPEG1 default
S170 = type 6 = SMPTE 1700M standard
S240 = type 7 = SMPTE 240M standard

I have some DVDs which has S170 coefficient. Should I use ColorMatrix before converting to ConvertToYUY2 for CCE and ConvertToRGB24 for TMPGE?

Some of my encodes are brighter than original. Could it be because I accidentally used RGB PC scale?