how to read a raw bitmap value independent of display

Question

4.00/5 (1 vote)

See more:

Hi,
I am learning the ropes of Visual C++. I want to load a bitmap file(DIB), find out individual raw pixel values(RGB) and process. I am understanding bitmap,palettes etc. I have tried:

C++

if (nColors > 256)
    m_palette.CreateHalftonePalette (&dc);

   pOldPalette = pDC->SelectPalette (m_palette, FALSE);
   pDC->RealizePalette ();
   CDC memDC;
   memDC.CreateCompatibleDC (pDC);
   CBitmap* pOldBitmap = memDC.SelectObject (pBitmap);
   memDC.GetPixel(x,y)

Would this give me the accurate pixel values? Independent of palette, if at all it is necessary. Thanks in regards,
-DJ

Posted 18-Feb-13 20:06pm

Member 8051611

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Michael Haephrati · Answer 1 · 2013-03-03T07:45:00

Solution 1

GetPixel() will return a COLORREF data type. You can then get 3 values (Red, Green, and Blue) using the following formula:
The low-order byte will contain the Red value, the second byte is for green, and the third byte contains a value for blue.

Posted 3-Mar-13 7:45am

Michael Haephrati