tolerance range?

[troller]

hey guys.

i have a question.

how exactly tolerance works?

for example i have color 100000 and the tolerance is set to 1.

will it search for color 99999, 100000 and 100001 or what?

same question for bitmaps

[slacky]

Color similarity is "a bit" more advanced than that, I can go through the default method in SCAR (known as CTS1) for you.

- This is what's by default used in find color and find bitmap methods.

 

The value you have there is a (numeric) representation of a RGB color.

var
 R,G,B:Integer;
begin
 ColorToRGB(100000, R,G,B);  
 WriteLn(TIAToStr([R,G,B]));
end.      

So your example value of 100000 = R: 160, G: 134, B: 1

 

From the beginning now knowing that:

SCAR convert the representation of the color to R, G and B values by doing some bitshifting (separating the 3 first bytes from the 4 byte long number), as so:

procedure ColorToRGB(Color:Integer; out R,G,B:Integer);
begin
 R := color and $FF;
 G := color shr 8 and $FF;
 B := color shr 16 and $FF;
end;

 

Then it compares the color using a function which computes the euclidean distance between the two colors:

function ColorSimilarity(Color1, Color2:Integer): Extended;
var 
 R1,B1,G1, R2,G2,B2: Integer;
begin
 ColorToRGB(Color1, R1,G1,B1);
 ColorToRGB(Color2, R2,G2,B2); 
 Result := Sqrt( Sqr(R1-R2) + Sqr(G1-G2) + Sqr(B1-B2) );
end;

 

That means the max tolerance used between two colors when using CTS1 (the formula shown above) is 442 (441,673)

 

 

`Tolerance` measured this way yields an "exponential-ish growth" in the number of similar colors (up to values):

1 tolerance: ~7 colors
2 tolerance: ~33 colors
3 tolerance: ~123 colors
4 tolerance: ~257 colors
...
8 tolerance: ~2109 colors
...
16 tolerance: ~17077 colors

Side note: The number of colors in RGB-color space is (256^3) = 16777216 (0 to 16777215)

 

--------------------

 

Based on your example color of 100000, using that with this formula and 1 tolerance that would give you the following values:

`(99999, 99744, 34464, 100000, 165536, 100256, 100001)`

 

Which is equal to the RGB colors:

--------(159,134,1) (160,133,1)

(160,134,0) (160,134,1) (160,134,2)

--------(160,135,1) (161,134,1)

 

--------------------------------------------------

 

Read: http://wiki.scar-divi.com/Tolerance

I hope this helps, tho if you have any more questions, just ask! :-)

Edited September 10, 2014 by slacky

[troller]

wow, that explains a lot of things.

i have another question too, not the same as above, but related to colors.

is there something in scar 3.22 that can change the search pattern of colors/bitmaps?

i want to find a color(pixel2) around a colored pixel(pixel1). there are many moving pixels(pixel2) there and i want to click the closest one(pixel2). is this possible?

[slacky]

wow, that explains a lot of things.

i have another question too, not the same as above, but related to colors.

is there something in scar 3.22 that can change the search pattern of colors/bitmaps?

i want to find a color(pixel2) around a colored pixel(pixel1). there are many moving pixels(pixel2) there and i want to click the closest one(pixel2). is this possible?

I don't use, nor do I have experience with older scar-versions.

 

There is generally no support to get here for prehistoric SCAR-versions. Update you SCAR to the latest and people here can actually help.. rather then using a version of SCAR which belongs in a museum.

Edited September 10, 2014 by slacky