iPhone SDK - CGBitmapContextCreate
I would like to create an image of my own. I already k开发者_如何学JAVAnow its width (320*2 = 640) and height (427).
So I have some raw data :
unsigned char *rawImg = malloc(height * width * 4 *2 );
Then, I will fill it :)
Then, I have to do something like that to get a bitmap and return a (UIImage *) :
ctx = CGBitmapContextCreate(rawImg,width*2,height,8,
???,
???,
kCGImageAlphaPremultipliedLast);
UIImage * imgFinal = [UIImage imageWithCGImage:CGBitmapContextCreateImage(ctx)];
CGContextRelease(ctx);
return imgFinal;
But I don't know how to create my context ctx, as you can see with the "???", even tough I read the documentation...
Please help ! Thanks :)
See Apple's CGBitmapContext documentation.
If you are using 4 bytes per pixel, then your bytes per row might be your half_width * 2 * 4.
Color space might be:
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
You can obtain the current CGContextRef
using
CGContextRef context =
UIGraphicsGetCurrentContext()
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