[iOS]从UIImage得到RGB32的方法

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info 

{
	UIImage *ImageA = [info valueForKey:UIImagePickerControllerOriginalImage];
	CGImageRef image = [ImageA CGImage];
	CGSize image_size = ImageA.size;
	CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
	void* data = malloc(image_size.width * image_size.height * 4);
	CGContextRef context = 
	CGBitmapContextCreate(data, image_size.width, image_size.height, 8, 4 * image_size.width, colorSpace, 
						kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
	CGContextDrawImage(context, CGRectMake(0, 0, image_size.width, image_size.height), image);
	/*
	data中就是你要得原始bmp图了, 没有文件头
	*/
	CGContextRelease(context);
	free(data);

}

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