BI_BITFIELDS

[oex]

Is BI_BITFIELDS just RGB(A) in a different order or do I need to rewrite my Bitmap code :/....

White is coming out purple whether I switch G&B or not....

These are the first 3 (palette?) colors
16711680
65280
255

It's a lot of code to sort out and rewrite without my macros but I think what I've given will make sense to someone who had dealt with BI_BITFIELDS.... I know that it can have different bit resolutions for different colors but this is data from the clipboard....

As I understand it from the data I have the first 3 data colors are palette colors RGB and then a normal BI_RGB follows (but based on these colors)....

Some infos are here: http://en.wikipedia.org/wiki/BMP_file_format

So long as I can validate the format I have and retrieve data from it I dont really care about other formats/possibilities for now....

Code Select Expand


19778
0
0
0
0

BITMAPINFOHEADER
40
1280
1024
1
32                    <---- 32 Bit
3                     <---- BI_BITFIELDS
5242880
0
0
0
0
16711680              <---- First 3
65280
255
1655205               <---- First Pixel


[donkey]

No, BI_RGB uses 555 encoding while BI_BITFIELDS uses 565 encoding in 16 bit color.

[oex]

This is 32 bit

Code Select Expand


BITMAPINFOHEADER
40
1280
1024
1
32                    <---- 32 Bit
3                     <---- BI_BITFIELDS
5242880
0
0
0
0
16711680              <---- First 3             00FF0000h
65280                                           0000FF00h
255                                             000000FFh
1655205               <---- First Pixel


I think the last 4 DWORDs are represented right.... The first 3 *I think* represent RGB.... Then it carries on and represents the data....

Maybe a more precise link?

Is this an Endian Issue????

FF0000 B
00FF00 G
0000FF R

[donkey]

Well, BI_BITFIELDS is generally used for 16 bit, however for 32 bit it is not always RGB(A) or (A)BGR. The position of the colors and alpha channel in a BI_BITFIELDS image in 32 bit depend on the masks. You use a BITMAPV5HEADER and set the bV5RedMask, bV5GreenMask, bV5BlueMask and bV5AlphaMask to assign the bits to the appropriate colors, using a regular header the palette is used to store the masks. For example using BI_BITFIELDS on a 32 bpp image you can have RABG if you like, its up to the programmer to set the order of the colors, you can even interleave them if you want.

[oex]

Oh I get it nice 1 ty!