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  #121  
06-25-2003, 10:41 AM
audi2honda audi2honda is offline
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so you guys are telling me gripcrop() evaluates and crops every frame? I didn't know this. I'm going to try with some hardcoded bicubic values from FitCD or moviestacker to see if I get a difference in prediction accuracy or CQ.

If gripcrop() happens to hack one frame more then the other compression is going to be all over the place. You may get more comression in the end, but it will be very hard to predict a file size. That is if I'm understanding this correctly.
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  #122  
06-25-2003, 10:43 AM
jorel jorel is offline
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ok Phil, you are clear.

see:
my new tv don't like overscan2..
show a big black border only on the left,more or less 2 centimeters.
can i adjust this changing some values to centre the image?
i ask cos i think that overscan 2 give me more compression than overscan 1, don't?

thanks.
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  #123  
06-25-2003, 11:31 AM
kwag kwag is offline
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Quote:
Originally Posted by ozjeff99
A problem too is that the resizing in Gripsize() is using different parameters frame by frame and this will no doubt affect file size etc.
No it doesn't work that way
When you open an .avs file that has GripFit functions, the first call to the filter analyzes a number of random frames, and then it chooses the size, etc. Then on succesive calls after frame 0, it doesn't recalculate frame size at all. It remembers that it's already running, and simply applies the resizing it found on the first run.

-kwag
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  #124  
06-25-2003, 11:37 AM
audi2honda audi2honda is offline
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Quote:
Originally Posted by kwag
Quote:
Originally Posted by ozjeff99
A problem too is that the resizing in Gripsize() is using different parameters frame by frame and this will no doubt affect file size etc.
No it doesn't work that way
When you open an .avs file that has GripFit functions, the first call to the filter analyzes a number of random frames, and then it chooses the size, etc. Then on succesive calls after frame 0, it doesn't recalculate frame size at all. It remembers that it's already running, and simply applies the resizing it found on the first run.

-kwag
This is good to know. If it changed every frame the movie could look pretty wacked. It On dark scenes it could crop the whole scene out.
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  #125  
06-25-2003, 01:05 PM
jorel jorel is offline
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@ all

see the posts of trillium
about gripfit problems:

http://www.kvcd.net/forum/viewtopic.php?t=4644
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  #126  
06-25-2003, 06:40 PM
ozjeff99 ozjeff99 is offline
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We dont have red herrings down here but I think I found one . Apologies for the distraction. A question is whether asharp and undot filtering the black borders of the source is hopefully transferred to the sampling in a linear way.
ozjeff99
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  #127  
06-26-2003, 04:20 AM
Dialhot Dialhot is offline
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Quote:
Originally Posted by ozjeff99
Dialhot..I hope you are right. But how much of the movie does it analyse to get the values.
The default is 5 (you can change it with "sample" parameter. See http://www.kvcd.net/forum/viewtopic.php?t=2292).

Quote:
If it was on the basis of the first frame and it was black, what values would it pick?
Sansgrip is smarter than this

GripCrop doesn't take the 5 first frames, it takes tham within the all length of the video. Then it keeps only the "most common values" calculated on this 5 frames. Chances are poor to have 5 frames that are all too dark to find the borders.
(This case leads to an error "GripCrop: Auto-detection of borders failed")

Quote:
And if it picked an average value for the movie would this value be different if the clip was a sampler for prediction?
ozjeff99
It can't as taking a sampler for prediction doesn't change anything to the size of the frames.
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  #128  
06-26-2003, 08:09 AM
ozjeff99 ozjeff99 is offline
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Thanks for a very educational post Dialhot. Obviously I was making a point before about the black frame. I agree that Sansgrip is way to smart
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  #129  
06-26-2003, 08:12 AM
Dialhot Dialhot is offline
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Quote:
Originally Posted by jorel
ok Phil, you are clear.

see:
my new tv don't like overscan2..
show a big black border only on the left,more or less 2 centimeters.
can i adjust this changing some values to centre the image?
First, if I were you, I'll try to fix my TV set ! It's not normal to have a picture not centered on the screen. If you have a worldwise know brand (Sony, Philips...) you can surely find on the net how to access to the "technical menu".

But of course you can solve the problem with movistacker using bicubicresize insteed of gripcrop.

The line to modify is the "Addborder".If Moviestacker suggest you "AddBorders(16,16,16,16)" for instance, juste put "Addborders(12,16,20,16).
(parameters for Addborder are left, top, right, bottom).

You'll move the picutre slighly on the left.

Quote:
i ask cos i think that overscan 2 give me more compression than overscan 1, don't?
The less you have image to encode, the more the comression is.
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  #130  
06-26-2003, 08:30 AM
jorel jorel is offline
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ok Phil


i worked with eletronics(tvs,vk7,dvd,cds..etc)
from 30 years and i adjust the width(horizontal) and size(vertical)
with extreme precision, right in the bordes of cinescope.
i only see this line when i encode using overscan2,
the channels,dvds and other sources are perfects.

after this adjusts i see a thin line only in this tv(29 Phillips),
the others(4) using overscan 2 works fine without black board on the left.

thank you for this all, friend!
great.
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  #131  
06-26-2003, 09:33 AM
jorel jorel is offline
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testing again

if i use (overscan2):
BicubicResize(448,448,0,0.6,0,0,712,480)
AddBorders(16,16,16,16)

i see a thin dark grey line on the left
within(under) the black border
on my monitor (using extreme bright).
load the script and see the video preview in ToK

this is what i see in my tv,isn't the border is this "dark grey line".

anyone can see this in the video preview?


EDITING:
was my dvd source,
i load from another dvd and the thin "dark grey line" dissapear!
incredible!
using gripfit is perfect
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