BITMAPINFOHEADER + buffer to Magick::Image

[anotherprogrammer123]

Hello,
(Here is a similar topic I posted back earlier (and found a solution to).)
For a DirectShow application, I want to transfer a BITMAP image info a Magick::Image. Basically, I have a BITMAPINFOHEADER and a BYTE* buffer pointing to the pixel data of the bitmap described by the BITMAPINFOHEADER.

Code: Select all

int bitmapToMagick(BITMAPINFOHEADER* bmiHeader, char* bitmap, size_t length, Magick::Image &Image) {
        //...code here...//
}

I have spent quite a bit of time trying to figure this out, but couldn't.
I found this post, but extracting the image_info members would be a really complicated function (converting from BITMAPINFOHEADER to Magick::ImageInfo). Also, for some reason ImageInfo.size is a char* array (how can I specify a 720x480 image with a char* array?). With more searching, I did find a DIBToImage() function here which does the job, but this seems too complicated.

The thing is that I can easily write the BITMAP to disk and read it back into a Magick::Image with ReadImage, but this is a very expensive operation. I looked through the Magick source code (Image.cpp, constitute.cpp), but could not find the function used to read from .bmp files (very similar to what I want to do).

There should be an easy way to do this right?
Thank you very much in advance for any help.

Also, please post back if anything is unclear.

[magick]

You can get direct access to the image pixels with Magick::Pixels (http://www.imagemagick.org/Magick++/Pixels.html) or you write directly to a char buffer with Magick::Image::write() (e.g. image.write( 0, 0, 640, 1, "RGB", 0, pixels )).

[anotherprogrammer123]

[please delete this post]

[anotherprogrammer123]

[please delete this post]

[anotherprogrammer123]

Hello again. This is the solution that I came up with:

Code: Select all

int bitmapToMagick(BITMAPINFOHEADER* bmiHeader, char* pixels, size_t length, Magick::Image* Image) {
	try {
		Image->read(bmiHeader->biWidth, abs(bmiHeader->biHeight), "BGR", Magick::CharPixel, pixels);
		Image->flip();
	}
	catch (...)  {
		return 1; ///error
        }
	return 0;
}

However, this is probably not the most efficient method (due to flip()). It also assumes the BITMAP is in BGR format, bottom-up, and has no compression.
This was very tricky. Hopefully the next Magick++ release will have more functions for dealing with BITMAPs

[amilkh]

In case anybody else runs in to this problem, I posted some guides to my website:
Converting uncompressed BITMAPs to Magick++ objects
Converting compressed BITMAPs to Magick++ objects