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@omarojo
Last active July 11, 2022 08:57
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Image to CVPixelBuffer OBJC
let myPixelBuffy = [self pixelBufferFromCGImage:[[UIImage imageNamed:@"myImage.png"] CGImage]];
- (CVPixelBufferRef)pixelBufferFromCGImage:(CGImageRef)image
{
CGSize frameSize = CGSizeMake(CGImageGetWidth(image), CGImageGetHeight(image));
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,
[NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey,
nil];
CVPixelBufferRef pxbuffer = NULL;
CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, frameSize.width,
frameSize.height, kCVPixelFormatType_32ARGB, (CFDictionaryRef) options,
&pxbuffer);
NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);
CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(
pxdata, frameSize.width, frameSize.height,
8, CVPixelBufferGetBytesPerRow(pxbuffer),
rgbColorSpace,
(CGBitmapInfo)kCGBitmapByteOrder32Little |
kCGImageAlphaPremultipliedFirst);
CGContextConcatCTM(context, CGAffineTransformMakeRotation(0));
CGAffineTransform flipVertical = CGAffineTransformMake( 1, 0, 0, -1, 0, CGImageGetHeight(image) );
CGContextConcatCTM(context, flipVertical);
CGAffineTransform flipHorizontal = CGAffineTransformMake( -1.0, 0.0, 0.0, 1.0, CGImageGetWidth(image), 0.0 );
CGContextConcatCTM(context, flipHorizontal);
CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image),
CGImageGetHeight(image)), image);
CGColorSpaceRelease(rgbColorSpace);
CGContextRelease(context);
CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
return pxbuffer;
}
@ikishorek
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Awesome!

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