ios AVAssetWriter output invalid video format - ios

Question

This code works for creating video from images. AVAssetWritter work fine without error and export output video - (.mov). But it fail in some case of image size.
120 x 160 - fail
180 x 640 , 240 x 320, 160 x 213.333, 96 x 128 - pass
P/s: Test on iPod 4th ios 5.1
This is screenshot http://postimg.org/image/gih1ofvbn/ of fail video for size 120 x 160, please help me solve this issue. Or any recommend for other video encoder library will be welcome. Thanks
This is my code
- (void) writeImagesAsMovie:(NSArray *)images withDelaySec:(float)delaySec toPath:(NSString*)path {
//delete file
NSFileManager *fileMgr = [[NSFileManager alloc] init];
NSError *error2;
if ([fileMgr removeItemAtPath:path error:&error2] != YES)
NSLog(#"Unable to delete file: %#", [error2 localizedDescription]);
UIImage *first = [images objectAtIndex:0];
CGSize frameSize = first.size;
NSLog(#"__create video: %f %f", frameSize.width, frameSize.height);
NSError *error = nil;
AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:
[NSURL fileURLWithPath:path] fileType:AVFileTypeQuickTimeMovie
error:&error];
if(error) {
NSLog(#"error creating AssetWriter: %#",[error description]);
}
int numPixels = frameSize.width * frameSize.height;
int bitsPerSecond;
float bitsPerPixel;
// Assume that lower-than-SD resolutions are intended for streaming, and use a lower bitrate
if ( numPixels < (640 * 480) )
bitsPerPixel = 4.05; // This bitrate matches the quality produced by AVCaptureSessionPresetMedium or Low.
else
bitsPerPixel = 11.4; // This bitrate matches the quality produced by AVCaptureSessionPresetHigh.
bitsPerSecond = numPixels * bitsPerPixel;
NSDictionary *videoCompressionSettings = [NSDictionary dictionaryWithObjectsAndKeys:
AVVideoCodecH264, AVVideoCodecKey,
[NSNumber numberWithInteger:frameSize.width], AVVideoWidthKey,
[NSNumber numberWithInteger:frameSize.height], AVVideoHeightKey,
[NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInteger:bitsPerSecond], AVVideoAverageBitRateKey,
[NSNumber numberWithInteger:30], AVVideoMaxKeyFrameIntervalKey,
nil], AVVideoCompressionPropertiesKey,
nil];
AVAssetWriterInput *writerInput = [[AVAssetWriterInput alloc] initWithMediaType:AVMediaTypeVideo outputSettings:videoCompressionSettings];
writerInput.expectsMediaDataInRealTime = YES;
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:
[videoWriter startWriting];
[videoWriter startSessionAtSourceTime:kCMTimeZero];
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);
}
float delayMili = delaySec * 25;
int fps = 30;
int i = 0;
for (UIImage *imgFrame in images)
{
if (adaptor.assetWriterInput.readyForMoreMediaData) {
i++;
CMTime frameTime = CMTimeMake(delayMili, fps);
CMTime lastTime = CMTimeMake(delayMili * i, fps);
CMTime presentTime = CMTimeAdd(lastTime, frameTime);
NSLog(#"__presentTime: %f", CMTimeGetSeconds(presentTime));
buffer = [self pixelBufferFromCGImage:[imgFrame CGImage]];
BOOL result = [adaptor appendPixelBuffer:buffer withPresentationTime:presentTime];
if (result == NO) //failes on 3GS, but works on iphone 4
{
NSLog(#"failed to append buffer");
NSLog(#"The error is %#", [videoWriter error]);
}
if(buffer) {
CVBufferRelease(buffer);
}
} else {
NSLog(#"error");
i--;
}
}
//Finish the session:
[writerInput markAsFinished];
[videoWriter finishWriting];
CVPixelBufferPoolRelease(adaptor.pixelBufferPool);
[videoWriter release];
[writerInput release];
NSLog(#"Movie created successfully");
}

Answer 1

The width of the video should be divisible by 16.