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Just one thing WIlbert about the test you did in the other thread on this problem :

Avs command "BlanckClip(color=$000000) gives a picture with Luma already clipped to 16. As does "BlanckClip(color=$ffffff) that gives L=235.

And is not even said in the doc.

Quote:

Originally Posted by Dialhot

Old TV sets had problems with extrem values as picture too dark or too bright.

Well I bought this 27" Samsung TV two years ago and just noticed while fighting with moving dark blocks in bark sceens in my encodes that I couldn't really see on my PC, that when watching a movie ,DVD or from Satilite that the blocks will also apear in bark areas. And was wondering if Limiter() would help my TV with these block ? should I buy a new TV :)

Quote:

Originally Posted by Dialhot

Old TV sets had problems with extrem values as picture too dark or too bright. That is why the standard CCIR601 was decided. As on these old screens, the material wasn't black indeed but very dark green, I think this problem wasn't a real one.

Now, as there are TV set with perfectly dark screen, that is an other question.

Same for limitation in high value : the problem appears only on weak electronics (the image seems to "pump" when you have a very bright area to display). In 2003, all TV set can handle very high luma.

I think Jorel can say something more on this point : that is his everyday labor :-)

exact Phil,
i can't find better words.

the old tv "delta tubes" have extreme bright limitations
and show the very high light as "neon lights".
then if one matiz is changed,all the colors change too cos
the white is the result all basic colors in tv
(59%green,30%red and11%blue = pure white.
pure white means..... :roll: "not so pure"
the "intention" of the limiter filter is special for this cases.
the instable linearity from black to white change the matizes
and the "background" grey of the luminance
can't show the light grey or black cos the "cannons"
don't do the perfect job.
in the new tvs is different and we got more bright
with less "miliamperes" and better balance betwwen the cannons.
:arrow: sorry my poor english.

ps:
"instable linearity" ?
8O

ahhh,you understand what i mean.
:lol: :lol:

I love to see professional explanations :-)

Quote:

Avs command "BlanckClip(color=$000000) gives a picture with Luma already clipped to 16. As does "BlanckClip(color=$ffffff) that gives L=235.

And is not even said in the doc.

True. When converting to YUY2/YV12 (after for example making a clip with BlankClip) in AviSynth, it always converts to YUY2/YV12 with range [16,236].

So, it's impossible to get L=0 in AviSynth using BlankClip, Levels, ColorYUV, etc. The only way is to import a clip with L=0 (made with TMPGEnc for example).

Quote:

Originally Posted by Wilbert

So, it's impossible to get L=0 in AviSynth using BlankClip, Levels, ColorYUV, etc. The only way is to import a clip with L=0 (made with TMPGEnc for example).

not xactly. coloryuv can do it as its default is 0-255 (opt=""). try coloryuv(off_y=-16) on BlankClip(black). For widening the luma range try gain_y or cont_y (the latter is a bit tricky!)

the bests
y

Hi all..

Just my two cents on this..

Bchteam wrote:

Quote:

I really assume that it has nothing to do with script, the Vob's or whatsoever. It's a TV related thing.

Or, its most likely you DVD player. I know this to be true, because I have
three of them still up and running ie, 2 Apex AD-1500 and 1 AD-500,
and the AD-500 diaplays my DVDs very lightly in color.. so I do see some
of those blochy blocks floating around when scenes are solid etc.

I don't think it's a TV issue, but it could be too.. I really think its a DVD
player issue alltogether :!:

-vhelp

Quote:

Originally Posted by jorel

thanks for redo my answer plautzer :wink:
i see the same like you and more:
the blocky dark seems "dark green" too.

:!:

back to the past(or future):
posted by SIF
about "dark green", limiter, mpegedec3 and some more.
...see the explanations from Sh0dan
(chrominance 128 is grey, 0 is green)
posted in 1st September 2003 12:50 about dark green:

http://forum.doom9.org/showthread.php?s=&threadid=60540

i still can see the dark green in some scenes!
:!:

more about levels and scales:

http://forum.doom9.org/showthread.php?s=&threadid=61537

and the last avisynth252 that i found:

http://cultact-server.novi.dk/kpo/avisynth/avs_cvs.html

ps:
don't know why Sh0dan don't call for news versions?!?
:?
and why the "green dark" was forgoten?!?!
...still there!

:roll:

more about "dark green":

http://forum.doom9.org/showthread.php?s=&threadid=61927

thanks God,after months i'm not the only one who see it!

For me if you check convert to yuv in tmpgenc, all dct blocks become invisible, but that's only dct.

I use deen and i gets rid of alot of background noise.

what i need is a filter that can reduce blocks on flat areas.

oh yes muhali3,
i'm using(testing) Deen("a3d",3,4,1,4), very cool for animes!

but about the "dark green"...
from the tmpgenc help file:
"Output YUV data as basic YCbCr, not CCIR601
Enabling this cause the 8-bit value for the components to be of a value between
0 and 255 in YCbCr, and not the CCIR601 values of 16 to 235.
This is usually disabled."

:arrow: the problem of dark green is between 0(zero) to 16!
for me, less than 16 means "more than black".
then it can turn it worse,don't?
:?