Using Avisynth to help compressing files

[Razorholt]

I think I have a great combinaison of filters here. Although I'm not sure about the order...

SPresso(2,33,4)
DeGrainMedian(limitY=5,limitUV=7,mode=1)
Undot()
Unfilter(-5,-5)
BilinearResize(800,448)

[Jeremy Duncan]

Originally Posted by Didée

May I hop in with a small function?

SPresso() is one I use a lot (mostly for internal processing within more complex functions), but it also deals very well as a standalone.

(It doesn't matter if you like caffeine or not (I do) - SPresso stands for Spatial Pressdown.)

On my usual, usual-noisy DVB sources, compression gain usually is from 2% to 3% (light settings -> changes almost invisible) up to 10 to 12% (stronger settings -> slight, gentle softening, not very obvious).

Format:

SPresso( limit, bias, [RGmode] )

"limit" tells the maximum change to do to any pixel
"bias" is, well, something like "aggessivity": '20' is a very light setting, '33' is already quite strong.
"RGmode" tells the RemoveGrain mode to use. The default of "4" is the best in most cases.

Posting screenshots makes not much sense, because there is so little difference to see. So just try it. Needed are MaskTools and RemoveGrain.

function SPresso(clip clp, int "limit", int "bias", int "RGmode")
{
limit  = default( limit,  2 )
bias   = default( bias,  25 )
RGmode = default( RGmode, 4 )

LIM1  = (limit>0) ? string( round(limit*100.0/bias-1.0) ) : string( round(100.0/bias) )
LIM2  = (limit<0) ? "1" : string(limit)
BIA   = string(bias)

expr  = (limit<0) ?   "x y - abs "+LIM1+" < x x 1 x y - x y - abs / * - ?"
 \                :   "x y = x x "+LIM1+" + y < x "+LIM2+" + x "+LIM1+" - y > x "+LIM2+" - " \ 
                    + "x 100 "+BIA+" - * y "+BIA+" * + 100 / ? ? ?"

yv12lutxy( clp, clp.removegrain(RGmode,-1), expr, U=2,V=2)
}

Note: Chroma is not touched at all. Spresso works only on the luma channel. Could be changed easily, however.

BTW: For those prefering tee over coffe, there's also a "TPresso" counterpart ... I just don't have it with me at the moment.

Could you please make a Spresso for Chroma.
Owen says that the Noise is mostly in Chroma, and I use HQDN3D(0.0, 2.0, 0.0, 4.0) so Chroma is affected but not Luma.
It would sure be nice if you could make a Spresso for Chroma only.

[Didée]

Supposely this "reduced-medianfilter" method isn't so awfully effective for removing chroma noise. Temporal filters should be a better choice here.

But, for what it's worth, here's SPresso extended to work on either luma, chroma, or both:

( EDIT 2006-09-04: corrected a BIG bug.)

function SPresso(clip clp, int "limit", int "bias", int "RGmode", int "limitC", int "biasC", int "RGmodeC")
{
limit   = default( limit,   2 )
limitC  = default( limitC,  4 )
bias    = default( bias,   25 )
biasC   = default( biasC,  50 )
RGmode  = default( RGmode,  4 )
RGmodeC = default( RGmodeC, 0 )

yy = (RGmode ==0) ? 2 : 3
uv = (RGmodeC==0) ? 2 : 3
LIM1  = (limit>0) ? string( round(limit*100.0/bias-1.0) ) : string( round(100.0/bias) )
LIM2  = (limit<0) ? "1" : string(limit)
BIA   = string(bias)
LIM1c = (limitC>0) ? string( round(limitC*100.0/biasC-1.0) ) : string( round(100.0/biasC) )
LIM2c = (limitC<0) ? "1" : string(limitC)
BIAc  = string(biasC)

expr  = (limit<0) ?   "x y - abs "+LIM1+" < x x 1 x y - x y - abs / * - ?"
 \                :   "x y - abs 0 <= x x "+LIM1+" + y < x "+LIM2+" + x "+LIM1+" - y > x "+LIM2+" - " \ 
                    + "x 100 "+BIA+" - * y "+BIA+" * + 100 / ? ? ?"
exprC = (limit<0) ?   "x y - abs "+LIM1c+" < x x 1 x y - x y - abs / * - ?"
 \                :   "x y - abs 0 <= x x "+LIM1c+" + y < x "+LIM2c+" + x "+LIM1c+" - y > x "+LIM2c+" - " \ 
                    + "x 100 "+BIAc+" - * y "+BIAc+" * + 100 / ? ? ?"

# For (old) MaskTools v1.5.8 :
# yv12lutxy( clp, clp.removegrain(RGmode,RGmodeC), expr,exprC,exprC, Y=yy,U=uv,V=uv)

# For (new) MaskTools v2.x :
mt_lutxy( clp, clp.removegrain(RGmode,RGmodeC), yexpr=expr,uexpr=exprC,vexpr=exprC, Y=yy,U=uv,V=uv)

return( last )
}

Per default, chroma still is not processed, just passed through. To also process chroma, call SPresso() with "RGmodeC=4" (or 19, or 20). To not process luma, set "RGmode=0".

[frednerk33]

Sorry, Spresso is mentioned in a LimitedSharpen thread, http://forum.doom9.org/showthread.ph...137#post867137 but can some kind soul point me to an explanation of what Spresso does and when to apply it ? Jeremy's link http://forum.doom9.org/showthread.ph...137#post867137 has the some flash-looking code. ... but I'm unsure what is it that SPresso is meant to do and why. It seems to be used in the context of noise filtering ?

[Jeremy Duncan]

Thank you very much.

[n3w813]

So the new call with chorma processing only would be....

SPresso(0, 0, 0, 4, 50, 4)

Right?

[Jeremy Duncan]

Originally Posted by n3w813

So the new call with chorma processing only would be....

SPresso(0, 0, 0, 4, 50, 4)

Right?

The bolded parts are Chroma.

SPresso(0, 4, 0, 40, 1, 17)

[n3w813]

Originally Posted by Jeremy Duncan

The bolded parts are Chroma.

SPresso(0, 4, 0, 40, 1, 17)

Are you sure...in the script it shows....

function SPresso(clip clp, int "limit", int "bias", int "RGmode", int "limitC", int "biasC", int "RGmodeC")

the variables with 'C' are the chroma settings right?

[Jeremy Duncan]

Originally Posted by n3w813

Are you sure...in the script it shows....

function SPresso(clip clp, int "limit", int "bias", int "RGmode", int "limitC", int "biasC", int "RGmodeC")

the variables with 'C' are the chroma settings right?

The Bolded are the Chroma.

limit = default( limit, 2 )
limitC = default( limitC, 4 )
bias = default( bias, 25 )
biasC = default( biasC, 50 )
RGmode = default( RGmode, 4 )
RGmodeC = default( RGmodeC, 0 )

SPresso(0, 4, 0, 40, 1, 17)

[foxyshadis]

NO NO NO, it's the order in the function definition that's important, and this is a good time to reiterate:

Don't call functions with bare arguments, use names, never worry about the order.

Otherwise it happens all the time, you upgrade a dll or script and the video turns green and looks vertically blurred, or whatever, because the order of arguments changed. Or an argument was swapped out with one with an entirely different meaning. Named optional arguments are one of the biggest conveniences of avisynth; even if the calls get wider they get much more understandable.

Btw, SPresso is essentially what SeeSaw does when you supply no denoised argument, right? (Its effect is that high freqency noise is smoothed out somewhat, though I'm not entirely sure of the details; a quick n' dirty one.)

[n3w813]

Originally Posted by foxyshadis

Don't call functions with bare arguments, use names, never worry about the order.

So.....if using MT......
MT("SPresso(limit=0, bias=0, RGmode=0, limitC=4, biasC=50, RGmodeC=4)",3)

Sorry, I'm a REAL n3w813 when it comes to avisynth scripts. :P

[foxyshadis]

Either order will work just fine now; the precise values are open to taste.

[Jeremy Duncan]

Originally Posted by n3w813

So.....if using MT......
MT("SPresso(limit=0, bias=0, RGmode=0, limitC=4, biasC=50, RGmodeC=4)",3)

Sorry, I'm a REAL n3w813 when it comes to avisynth scripts. :P

MT("SPresso(limit=0, limitC=4, bias=0, biasC=40, RGmode=1, RGmodeC=17)",3)

The colors will be messed up if you don't use at least #1 on RGmode.
I've bolded in the quote the setting that needs to be at least # 1.

[Boulder]

RGMode=0 should mean that luma is simply copied as it is - it shouldn't do anything to the colors. If it does, there's something wrong in Didée's function.

[Jeremy Duncan]

Originally Posted by Boulder

RGMode=0 should mean that luma is simply copied as it is - it shouldn't do anything to the colors. If it does, there's something wrong in Didée's function.

Using this code;

SPresso(limit=0, limitC=4, bias=0, biasC=40, RGmode=1, RGmodeC=17)

And setting RGmode=0, the colors go way off. It's very ugly.

[Didée]

I can't reproduce that. There's nothing wrong in the function, as far as I can see, and RGmode=0 / limit=0 works fine for me.


@ foxyshadis

Lol, good description of might happen. You forgot "video might start playing backwards".

Originally Posted by foxyshadis

Btw, SPresso is essentially what SeeSaw does when you supply no denoised argument, right? (Its effect is that high freqency noise is smoothed out somewhat, though I'm not entirely sure of the details; a quick n' dirty one.)

Yes, it's the same principle, only that SPresso's defaults are weaker. In SeeSaw, it's stronger because of the "indirect processing" that is done ... the denoising can be stronger, because more denoising only means there will be less detail (and thereby less artefacts) that will be sharpened.

Generally, Spresso is just a limited Removegrain(4). Put in words, SPresso(RGmode=4,bias=25,limit=2) reads:

"Apply 25% of RemoveGrain(4), with a maximum pixelchange of +/- 2".

[BigDid]

Originally Posted by Didée

... Generally, Spresso is just a limited Removegrain(4). Put in words, SPresso(RGmode=4,bias=25,limit=2) reads:

"Apply 25% of RemoveGrain(4), with a maximum pixelchange of +/- 2".

Thanks, crystal clear.

I really need to learn scripting more

Did

[frednerk33]

Originally Posted by Didée

Yes, it's the same principle, only that SPresso's defaults are weaker. In SeeSaw, it's stronger because of the "indirect processing" that is done ... the denoising can be stronger, because more denoising only means there will be less detail (and thereby less artefacts) that will be sharpened.

Generally, Spresso is just a limited Removegrain(4). Put in words, SPresso(RGmode=4,bias=25,limit=2) reads:

"Apply 25% of RemoveGrain(4), with a maximum pixelchange of +/- 2".

Teriffic, thanks for the clarfication.

[Jeremy Duncan]

Originally Posted by foxyshadis

I just thought I'd point out that this spresso suffers the same problem as the old deblock_qed, with a couple of incorrect = signs in the lut expr. (Should be ==.)

Is this the correct code ?

function SPresso(clip clp, int "limit", int "bias", int "RGmode", int "limitC", int "biasC", int "RGmodeC")
{
limit   = default( limit,   2 )
limitC  = default( limitC,  4 )
bias	= default( bias,   25 )
biasC   = default( biasC,  50 )
RGmode  = default( RGmode,  4 )
RGmodeC = default( RGmodeC, 0 )

yy = (RGmode ==0) ? 2 : 3
uv = (RGmodeC==0) ? 2 : 3
LIM1  = (limit>0) ? string( round(limit*100.0/bias-1.0) ) : string( round(100.0/bias) )
LIM2  = (limit<0) ? "1" : string(limit)
BIA   = string(bias)
LIM1c = (limitC>0) ? string( round(limitC*100.0/biasC-1.0) ) : string( round(100.0/biasC) )
LIM2c = (limitC<0) ? "1" : string(limitC)
BIAc  = string(biasC)

expr  = (limit<0) ?   "x y - abs "+LIM1+" < x x 1 x y - x y - abs / * - ?"
 \				:   "x y == x x "+LIM1+" + y < x "+LIM2+" + x "+LIM1+" - y > x "+LIM2+" - " \ 
					+ "x 100 "+BIA+" - * y "+BIA+" * + 100 / ? ? ?"
exprC = (limit<0) ?   "x y - abs "+LIM1c+" < x x 1 x y - x y - abs / * - ?"
 \				:   "x y == x x "+LIM1c+" + y < x "+LIM2c+" + x "+LIM1c+" - y > x "+LIM2c+" - " \ 
					+ "x 100 "+BIAc+" - * y "+BIAc+" * + 100 / ? ? ?"

# For (old) MaskTools v1.5.8 :
# yv12lutxy( clp, clp.removegrain(RGmode,RGmodeC), expr,exprC,exprC, Y=yy,U=uv,V=uv)

# For (new) MaskTools v2.x :
mt_lutxy( clp, clp.removegrain(RGmode,RGmodeC), yexpr=expr,uexpr=exprC,vexpr=exprC, Y=yy,U=uv,V=uv)

return( last )
}

[Didée]

Not bad. But I prefer the one some posts above.