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how to convert a jpeg file into a c++ matrix ?

Posted on 2003-12-01
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Last Modified: 2012-05-04
hi, i need to convert a jpeg file into a c++ 2D matrix, with each value representing the pixel's greyscale value of the jpeg file. Please help ? Thank you in advance ! =P
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Question by:Shifeng
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skypalae earned 63 total points
ID: 9856241
what about http://www.smalleranimals.com/jpegfile.htm ?? is it suitable enough?
S.
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by:JensUniweb
JensUniweb earned 62 total points
ID: 9856612
Unother alternative is http://www.ijg.org/. It's a widly spread library first made for for UNIX systems. But are now available on Windwos and other platforms to.
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by:DanRollins
ID: 9856663
Convert the JPG into a Bitmap (DIB Section).  Then you can access the pixel data:

    C++ Q&A: Displaying a JPG in your MFC Application -- MSDN Magazine, October 2001
    http://msdn.microsoft.com/msdnmag/issues/01/10/c/default.aspx
    http://msdn.microsoft.com/msdnmag/issues/01/10/c

    OleLoadPicture API call
    http://msdn.microsoft.com/library/en-us/com/htm/ofn_ol2z_0k4l.asp

    SAMPLE: How to Load and Display Graphics Files with LOADPIC.EXE
    http://support.microsoft.com/support/kb/articles/Q218/9/72.ASP

After you have converted it (in memory) and have an HBITMAP, I'll show you how to access the grayscale pixels as (X,Y) of a 2-D array.

-- Dan
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by:migoEX
ID: 10331438
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:

Split between skypalae,  JensUniweb and DanRollins.

Please leave any comments here within the next four days.

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

migoEX
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