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– (CVPixelBufferRef) pixelBufferFromCGImage: (CGImageRef) image






{











CGSize frameSize = CGSizeMake(CGImageGetWidth(image), CGImageGetHeight(image));






NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:






[NSNumber numberWithBool:NO], kCVPixelBufferCGImageCompatibilityKey,






[NSNumber numberWithBool:NO], 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, 4*frameSize.width, rgbColorSpace,






kCGImageAlphaNoneSkipLast);










CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image),






CGImageGetHeight(image)), image);






CGColorSpaceRelease(rgbColorSpace);






CGContextRelease(context);










CVPixelBufferUnlockBaseAddress(pxbuffer, 0);










return pxbuffer;






}

CGImageRef _cgImage = [self imageFromSampleBuffer:sampleBuffer];
UIImage *_uiImage = [UIImage imageWithCGImage:_cgImage];
CGImageRelease(_cgImage);
_uiImage = [_uiImage resizedImageWithSize:CGSizeMake(320, 280)];

CMSampleBufferRef croppedBuffer = /* NEED HELP WITH THIS */

[_videoInput appendSampleBuffer:sampleBuffer]; 
// _videoInput is a AVAssetWriterInput

- (CGImageRef) imageFromSampleBuffer:(CMSampleBufferRef) sampleBuffer // Create a CGImageRef from sample buffer data
{
    CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
    CVPixelBufferLockBaseAddress(imageBuffer,0);        // Lock the image buffer

    uint8_t *baseAddress = (uint8_t *)CVPixelBufferGetBaseAddressOfPlane(imageBuffer, 0);   // Get information of the image
    size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer);
    size_t width = CVPixelBufferGetWidth(imageBuffer);
    size_t height = CVPixelBufferGetHeight(imageBuffer);
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();

    CGContextRef newContext = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
    CGImageRef newImage = CGBitmapContextCreateImage(newContext);
    CGContextRelease(newContext);

    CGColorSpaceRelease(colorSpace);
    CVPixelBufferUnlockBaseAddress(imageBuffer,0);
    /* CVBufferRelease(imageBuffer); */  // do not call this!

    return newImage;
}

NSMutableDictionary* inputSettingsDict = [NSMutableDictionary dictionary];
[inputSettingsDict setObject:[NSNumber numberWithInt:pixelFormat] forKey:(NSString*)kCVPixelBufferPixelFormatTypeKey];
[inputSettingsDict setObject:[NSNumber numberWithUnsignedInteger:(NSUInteger)(image.uncompressedSize/image.rect.size.height)] forKey:(NSString*)kCVPixelBufferBytesPerRowAlignmentKey];
[inputSettingsDict setObject:[NSNumber numberWithDouble:image.rect.size.width] forKey:(NSString*)kCVPixelBufferWidthKey];
[inputSettingsDict setObject:[NSNumber numberWithDouble:image.rect.size.height] forKey:(NSString*)kCVPixelBufferHeightKey];
[inputSettingsDict setObject:[NSNumber numberWithBool:YES] forKey:(NSString*)kCVPixelBufferCGImageCompatibilityKey];
[inputSettingsDict setObject:[NSNumber numberWithBool:YES] forKey:(NSString*)kCVPixelBufferCGBitmapContextCompatibilityKey];
AVAssetWriterInputPixelBufferAdaptor* pixelBufferAdapter = [[AVAssetWriterInputPixelBufferAdaptor alloc] initWithAssetWriterInput:assetWriterInput sourcePixelBufferAttributes:inputSettingsDict];

[pixelBufferAdapter appendPixelBuffer:completePixelBuffer withPresentationTime:pixelBufferTime]

void GPUImageCreateResizedSampleBuffer(CVPixelBufferRef cameraFrame, CGSize finalSize, CMSampleBufferRef *sampleBuffer)
{
    // CVPixelBufferCreateWithPlanarBytes for YUV input

    CGSize originalSize = CGSizeMake(CVPixelBufferGetWidth(cameraFrame), CVPixelBufferGetHeight(cameraFrame));

    CVPixelBufferLockBaseAddress(cameraFrame, 0);
    GLubyte *sourceImageBytes =  CVPixelBufferGetBaseAddress(cameraFrame);
    CGDataProviderRef dataProvider = CGDataProviderCreateWithData(NULL, sourceImageBytes, CVPixelBufferGetBytesPerRow(cameraFrame) * originalSize.height, NULL);
    CGColorSpaceRef genericRGBColorspace = CGColorSpaceCreateDeviceRGB();
    CGImageRef cgImageFromBytes = CGImageCreate((int)originalSize.width, (int)originalSize.height, 8, 32, CVPixelBufferGetBytesPerRow(cameraFrame), genericRGBColorspace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst, dataProvider, NULL, NO, kCGRenderingIntentDefault);

    GLubyte *imageData = (GLubyte *) calloc(1, (int)finalSize.width * (int)finalSize.height * 4);

    CGContextRef imageContext = CGBitmapContextCreate(imageData, (int)finalSize.width, (int)finalSize.height, 8, (int)finalSize.width * 4, genericRGBColorspace,  kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
    CGContextDrawImage(imageContext, CGRectMake(0.0, 0.0, finalSize.width, finalSize.height), cgImageFromBytes);
    CGImageRelease(cgImageFromBytes);
    CGContextRelease(imageContext);
    CGColorSpaceRelease(genericRGBColorspace);
    CGDataProviderRelease(dataProvider);

    CVPixelBufferRef pixel_buffer = NULL;
    CVPixelBufferCreateWithBytes(kCFAllocatorDefault, finalSize.width, finalSize.height, kCVPixelFormatType_32BGRA, imageData, finalSize.width * 4, stillImageDataReleaseCallback, NULL, NULL, &pixel_buffer);
    CMVideoFormatDescriptionRef videoInfo = NULL;
    CMVideoFormatDescriptionCreateForImageBuffer(NULL, pixel_buffer, &videoInfo);

    CMTime frameTime = CMTimeMake(1, 30);
    CMSampleTimingInfo timing = {frameTime, frameTime, kCMTimeInvalid};

    CMSampleBufferCreateForImageBuffer(kCFAllocatorDefault, pixel_buffer, YES, NULL, NULL, videoInfo, &timing, sampleBuffer);
    CFRelease(videoInfo);
    CVPixelBufferRelease(pixel_buffer);
}