IOS green border when creating mov from UIImages

Question

I use the code below to take a series of UIImage and convert them to mov. For some reason, I continue to get a green border below or to the right, depending on whether the landscape or portrait photo. Images are 215x320.

How to remove green borders? Is there a better way to create .mov from UIImages?

- (void)createMov { UIImage *first = [self.videoFrames objectAtIndex:0]; CGSize frameSize = first.size; NSError *error = nil; AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL: [NSURL fileURLWithPath:fileName] fileType:AVFileTypeQuickTimeMovie error:&error]; if (error) { NSLog(@"error creating AssetWriter: %@",[error description]); } int numPixels = first.size.width * first.size.height; int bitsPerSecond = numPixels * 11.04; NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys: AVVideoCodecH264, AVVideoCodecKey, [NSNumber numberWithInt:frameSize.width], AVVideoWidthKey, [NSNumber numberWithInt:frameSize.height], AVVideoHeightKey, [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithInteger:bitsPerSecond], AVVideoAverageBitRateKey, [NSNumber numberWithInteger:30], AVVideoMaxKeyFrameIntervalKey, nil], AVVideoCompressionPropertiesKey, nil]; AVAssetWriterInput* writerInput = [[AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings] retain]; NSMutableDictionary *attributes = [[NSMutableDictionary alloc] init]; [attributes setObject:[NSNumber numberWithUnsignedInt:kCVPixelFormatType_32ARGB] forKey: (NSString*)kCVPixelBufferPixelFormatTypeKey]; [attributes setObject:[NSNumber numberWithUnsignedInt:frameSize.width] forKey:(NSString*)kCVPixelBufferWidthKey]; [attributes setObject:[NSNumber numberWithUnsignedInt:frameSize.height] forKey:(NSString*)kCVPixelBufferHeightKey]; AVAssetWriterInputPixelBufferAdaptor *adaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:writerInput sourcePixelBufferAttributes:attributes]; [videoWriter addInput:writerInput]; // fixes all errors writerInput.expectsMediaDataInRealTime = YES; //Start a session: BOOL start = [videoWriter startWriting]; NSLog(@"Session started? %d", start); [videoWriter startSessionAtSourceTime:kCMTimeZero]; // Writing. CVPixelBufferRef buffer = NULL; buffer = [self pixelBufferFromCGImage:[first CGImage]]; BOOL result = [adaptor appendPixelBuffer:buffer withPresentationTime:kCMTimeZero]; if (result == NO) //failes on 3GS, but works on iphone 4 NSLog(@"failed to append buffer"); if(buffer) CVBufferRelease(buffer); [NSThread sleepForTimeInterval:0.05]; int fps = [Utils frameRate]; int i = 0; for (UIImage *imgFrame in self.videoFrames) { i = [self addFrame:adaptor videoWriter:videoWriter buffer:buffer imgFrame:imgFrame i:i fps:fps]; } //Finish the session: [writerInput markAsFinished]; [videoWriter finishWriting]; CVPixelBufferPoolRelease(adaptor.pixelBufferPool); [videoWriter release]; [writerInput release]; } - (int)addFrame:(AVAssetWriterInputPixelBufferAdaptor *)adaptor videoWriter:(AVAssetWriter *)videoWriter buffer:(CVPixelBufferRef)buffer imgFrame:(UIImage *)imgFrame i:(int)i fps: (float)fps { if (adaptor.assetWriterInput.readyForMoreMediaData) { i++; NSLog(@"inside for loop %d",i); CMTime frameTime = CMTimeMake(1, fps); CMTime lastTime=CMTimeMake(i, fps); CMTime presentTime=CMTimeAdd(lastTime, frameTime); buffer = [self pixelBufferFromCGImage:[imgFrame CGImage]]; BOOL result = [adaptor appendPixelBuffer:buffer withPresentationTime:presentTime]; if (result == NO) { //fails on 3GS, but works on iphone 4 NSLog(@"failed to append buffer"); NSLog(@"The error is %@", [videoWriter error]); } if (buffer) { CVBufferRelease(buffer); } [NSThread sleepForTimeInterval:0.05]; } else { NSLog(@"error"); i--; } [NSThread sleepForTimeInterval:0.02]; return i; } - (CVPixelBufferRef)pixelBufferFromCGImage:(CGImageRef)image { NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey, [NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey, nil]; CVPixelBufferRef pxbuffer = NULL; CVPixelBufferCreate(kCFAllocatorDefault, CGImageGetWidth(image), CGImageGetHeight(image), kCVPixelFormatType_32ARGB, (CFDictionaryRef) options, &pxbuffer); CVPixelBufferLockBaseAddress(pxbuffer, 0); void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer); size_t rowBytes = CVPixelBufferGetBytesPerRow(pxbuffer); CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(pxdata, CGImageGetWidth(image), CGImageGetHeight(image), 8, rowBytes, rgbColorSpace, kCGImageAlphaNoneSkipFirst); CGContextConcatCTM(context, CGAffineTransformMakeRotation(0)); CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image), CGImageGetHeight(image)), image); CGColorSpaceRelease(rgbColorSpace); CGContextRelease(context); CVPixelBufferUnlockBaseAddress(pxbuffer, 0); return pxbuffer; } 

Answer 1

I seem to have a similar problem, and I had the idea of ​​coming out of my head after reading two posts, as shown below.

http://forum.videohelp.com/threads/314973-green-line-at-bottom-of-video-window

http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Features

 NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys: AVVideoCodecH264, AVVideoCodecKey, [NSNumber numberWithUnsignedLong:sourceWidth], AVVideoWidthKey, [NSNumber numberWithUnsignedLong:sourceHeight], AVVideoHeightKey, nil]; AVAssetWriterInput *writerInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings]; 

Before starting to write data using AVAssertWriter, please reset sourceWidth and sourceHeight using this method:

 size_t fixedLineValue(size_t sourceValue){ size_t divide = sourceValue%4; size_t finalValue = sourceValue; if (divide) { finalValue=(sourceValue/4+1)*4; } return finalValue; } 

I don’t know why to do this, but after that the ugly green borders were removed. Please comment if there is a better answer and make it clear. Thanks.