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Color Meter
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sjoemelfreek



Joined: 14 Sep 2008
Posts: 15

Post Color Meter Reply with quote
Hi there,

I am enjoying the challenges. The Didactic RGB is bothering me because my color meter is inconsistent.
I got a color meter that comes with my mac and it is possible to read the 24-bit integer from that program. Only it differs between computers and all my attempts where wrong anyway. I downloaded the file and converted the ASCII string to binary, but this gave me far to many bytes for a 24-bit integer.

Is my approach wrong or are my tools wrong?

Thanks
Sun Oct 12, 2008 9:04 am View user's profile Send private message
MerickOWA



Joined: 07 Apr 2008
Posts: 182
Location: HkRkoz al KuwaiT 2019 HaCkEr 101

Post Re: Color Meter Reply with quote
sjoemelfreek wrote:
Hi there,

I am enjoying the challenges. The Didactic RGB is bothering me because my color meter is inconsistent.
I got a color meter that comes with my mac and it is possible to read the 24-bit integer from that program. Only it differs between computers and all my attempts where wrong anyway. I downloaded the file and converted the ASCII string to binary, but this gave me far to many bytes for a 24-bit integer.

Is my approach wrong or are my tools wrong?

Thanks


The raw binary of the image will have more bytes in it than the 3 you need to solve the problem. All you need is to figure out the 24-bit integer of the single pixel you see.
Sun Oct 12, 2008 5:15 pm View user's profile Send private message
sjoemelfreek



Joined: 14 Sep 2008
Posts: 15

Post Reply with quote
Yes, but the tools I use that give me a 24-bit integer of the RGB apparently give me the wrong code.
If I can't trust the tools then I must find a way to uncover the color from the data I have: the file itself.
Sun Oct 12, 2008 5:26 pm View user's profile Send private message
tails



Joined: 10 Jun 2008
Posts: 191
Location: Tokyo

Post Reply with quote
Analysing the PNG binary is too tough. At least you had better convert it into more simple and plain format such as TGA and BMP when you need to look into it.

And, to solve this challenge with tools, you had better avoid capturing the screen to pick the color, because the color on the screen is the result of color correction. Also you should avoid using the meters which shows the color on the screen, because of the same reason. You need a tool which shows the raw color value of a pixel in an image.

Good luck!
Mon Oct 13, 2008 9:43 am View user's profile Send private message
canine



Joined: 14 Sep 2008
Posts: 189

Post Reply with quote
sjoemelfreek wrote:
Yes, but the tools I use that give me a 24-bit integer of the RGB apparently give me the wrong code.


Depending on what you choose to use, it won't be so hard. I had the same problem you did, until tails' post here revealed the way.

sjoemelfreek wrote:
If I can't trust the tools then I must find a way to uncover the color from the data I have: the file itself.


Hot damn, I like the way you think. It's like being on top of a tall building and, instead of just finding the stairs to the roof to go down, you rappel down the side while being chased by a fiery explosion.

A real man doesn't use an image editor for this; he uses a hex editor and reads the png binary.
Mon Oct 13, 2008 1:24 pm View user's profile Send private message
sjoemelfreek



Joined: 14 Sep 2008
Posts: 15

Post Reply with quote
problems is the PNG binary isn't that complicated only the image has a color type 2 or 4, otherwise it would be easy to retrieve...

Anyhow, I tried like 6 image editors and they all give a different data, so I am fed up now..
Mon Oct 13, 2008 3:32 pm View user's profile Send private message
canine



Joined: 14 Sep 2008
Posts: 189

Post Reply with quote
sjoemelfreek wrote:
problems is the PNG binary isn't that complicated only the image has a color type 2 or 4, otherwise it would be easy to retrieve...

Anyhow, I tried like 6 image editors and they all give a different data, so I am fed up now..


The Gimp gave me the correct value.
Mon Oct 13, 2008 5:30 pm View user's profile Send private message
sjoemelfreek



Joined: 14 Sep 2008
Posts: 15

Post Reply with quote
With the gimp you use color picker?

Because the color picker gives me the wrong info again (with GIMP as well)
Mon Oct 13, 2008 8:39 pm View user's profile Send private message
canine



Joined: 14 Sep 2008
Posts: 189

Post Reply with quote
sjoemelfreek wrote:
With the gimp you use color picker?

Because the color picker gives me the wrong info again (with GIMP as well)


What is the hex value it gives you?

Behold, my hex value near the bottom right hand corner.
Mon Oct 13, 2008 10:04 pm View user's profile Send private message
sjoemelfreek



Joined: 14 Sep 2008
Posts: 15

Post Reply with quote
Mmm, yeah, this is what it gives me too. I made a reading mistake Shocked

Anyhow, still I needed to try several editors (why GIMP?) before it gave me the right value.
Isn't there a more pure way to retrieve the value of an Image?

Thank you for your patience, though, to bad it ends with green (where is blue?)
Tue Oct 14, 2008 9:34 am View user's profile Send private message
canine



Joined: 14 Sep 2008
Posts: 189

Post Reply with quote
sjoemelfreek wrote:
Mmm, yeah, this is what it gives me too. I made a reading mistake Shocked

Anyhow, still I needed to try several editors (why GIMP?) before it gave me the right value.
Isn't there a more pure way to retrieve the value of an Image?

Thank you for your patience, though, to bad it ends with green (where is blue?)


Wat
Tue Oct 14, 2008 5:03 pm View user's profile Send private message
sjoemelfreek



Joined: 14 Sep 2008
Posts: 15

Post Reply with quote
didactic red, didactic green, where's didactic blue Wink
Tue Oct 14, 2008 7:21 pm View user's profile Send private message
vielinko



Joined: 09 Jan 2009
Posts: 5

Post Reply with quote
canine wrote:
sjoemelfreek wrote:
With the gimp you use color picker?

Because the color picker gives me the wrong info again (with GIMP as well)


What is the hex value it gives you?

Behold, my hex value near the bottom right hand corner.


Hey!

Well, i tried to solved this on a mac, without GIMP. Inicial i got a distinct value (hex/dec/bin) for the RGB color ...

I got those values:

982ABF

holy s... this didnt the real value .... sigh ...

instead

9C54C6

Then i Tried on GIMP and i got the same value than you canine ... and well .. that was my problem ... now is solved Razz

rgds
________
sc2 replay


Last edited by vielinko on Mon Jan 31, 2011 9:18 pm; edited 1 time in total
Tue Jan 13, 2009 4:08 pm View user's profile Send private message
zero0cripton



Joined: 21 Jan 2010
Posts: 6
Location: Portugal

Post Reply with quote
apparently windows' paint tell's you a different set of RGB for that colour.
Damn you Bill Gates! Twisted Evil

_________________
Sex is like hacking, you get in, you get out and you hope you didn't leave anything behind that can be traced back to you.
Tue Feb 02, 2010 7:25 pm View user's profile Send private message
thewino



Joined: 06 Apr 2011
Posts: 5

Post Reply with quote
i got different values from gimp as well. and i didn't read them wrong. i was only able to solve it thanks to the proper hex posted above. now im stuck on the didactic red challenge with improper hex values as well. this is the only trouble ive expressed and ive branched out further in all other directions in the challeneges.

if someone could please provide the 6digit hex values for each red value. that would be awesome. thanks.
Fri Apr 15, 2011 4:17 am View user's profile Send private message
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