iOS MOV rendering producing odd results (obj-c) - ios

Question

I'm creating an extension to an AS3 AIR application that will take in pixel data as ARGB32 and I want to render it to a .mov container using the H264 codec and then send it to the users camera roll. I'm currently running a test harness which takes an image from a local path (on my desktop) as a .jpeg, gets the pixel data out and renders it 50 times over into a short clip. The problem I'm having is when I render it on 400x200, it works fine however when I use an image of any other size, the frames come out very weirdly (images splayed diagonally, sometimes with a little black bar at the bottom right as if there are missing pixels).
I have a feeling its todo with the height and width as those are the only things that change from what I can see. Here is my code below:
- (void)initFunction:(NSString *)context width:(int)widthData height:(int)heightData fps:(int)fpsData
{
NSLog(#"Initializing...");
error = nil;
frameCount = 0; //Used for itterating
fps = fpsData; //FPS from AS3
width = widthData; //Width from AS3
height = heightData; //Height from AS3
numberOfSecondsPerFrame = 1.0f/(float)fps; //Seconds per frame
frameDuration = fps * numberOfSecondsPerFrame; //Frame showing time
imageSize = CGSizeMake(width, height); //imageSize from AS3
// Setup and remove pre-existing "render.mov"
fileMgr = [NSFileManager defaultManager];
documentsDirectory = [NSHomeDirectory() stringByAppendingPathComponent:#"Documents"];
videoOutputPath = [documentsDirectory stringByAppendingPathComponent:#"render.mov"];
if ([fileMgr removeItemAtPath:videoOutputPath error:&error] != YES)
{
NSLog(#"This is the first VS render on this device: %#", [error localizedDescription]);
}
else
{
NSLog(#"Removed previous render file in save path.");
}
NSLog(#"Starting render.");
videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:videoOutputPath] fileType:AVFileTypeQuickTimeMovie error:&error];
NSParameterAssert(videoWriter);
videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
AVVideoCodecH264, AVVideoCodecKey,
[NSNumber numberWithInt:width], AVVideoWidthKey,
[NSNumber numberWithInt:height], AVVideoHeightKey,
nil];
videoWriterInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:videoSettings];
NSDictionary *bufferAttributes = [NSDictionary dictionaryWithObjectsAndKeys
[NSNumber numberWithInt:kCVPixelFormatType_32ARGB], kCVPixelBufferPixelFormatTypeKey, nil];
adaptor = [AVAssetWriterInputPixelBufferAdaptor
assetWriterInputPixelBufferAdaptorWithAssetWriterInput:videoWriterInput
sourcePixelBufferAttributes:nil];
NSParameterAssert(videoWriterInput);
NSParameterAssert([videoWriter canAddInput:videoWriterInput]);
videoWriterInput.expectsMediaDataInRealTime = YES;
[videoWriter addInput:videoWriterInput];
//Start a session:
[videoWriter startWriting];
[videoWriter startSessionAtSourceTime:kCMTimeZero];
buffer = NULL;
NSLog(#"**************************************************");
}
-(void) sendToCameraRoll:(NSString *)videoPath {
UISaveVideoAtPathToSavedPhotosAlbum(videoPath, nil, NULL, nil);
}
//Take in URL from AIR
- (void)addFrameFromBytes:(CGImageRef *)FrameBytes {
UIImage *image = [UIImage imageWithCGImage:*FrameBytes];
CGImageRef cgImage = [image CGImage];
buffer = [self pixelBufferFromCGImage:cgImage];
append_ok = NO;
int j = 0;
while (!append_ok) {
if (adaptor.assetWriterInput.readyForMoreMediaData) {
frameCount = frameCount+1;
NSLog(#"Processing video frame %d",frameCount);
frameTime = CMTimeMake(frameCount*frameDuration,(int32_t) fps);
append_ok = [adaptor appendPixelBuffer:buffer withPresentationTime:frameTime];
[NSThread sleepForTimeInterval:0.1]; //Prevents system overload but causes lag.
if(!append_ok){
error = videoWriter.error;
if(error!=nil) {
NSLog(#"Unresolved error %#,%#.", error, [error userInfo]);
}
}
} else {
printf("Adaptor not ready %d, %d\n", frameCount, j);
[NSThread sleepForTimeInterval:0.1]; //Prevents system overload but causes lag.
}
j++;
}
if (!append_ok) {
printf("Error appending image %d times %d\n, with error.", frameCount, j);
}
}
//Take in Path from AIR
- (void)addFrameFromURL:(NSString *)FramePath {
UIImage *image = [UIImage imageWithContentsOfFile:FramePath];
CGImageRef cgImage = [image CGImage];
buffer = [self pixelBufferFromCGImage:cgImage];
append_ok = NO;
int j = 0;
while (!append_ok) {
if (adaptor.assetWriterInput.readyForMoreMediaData) {
frameCount = frameCount+1;
NSLog(#"Processing video frame %d",frameCount);
frameTime = CMTimeMake(frameCount*frameDuration,(int32_t) fps);
append_ok = [adaptor appendPixelBuffer:buffer withPresentationTime:frameTime];
[NSThread sleepForTimeInterval:0.1]; //Prevents system overload but causes lag.
if(!append_ok){
error = videoWriter.error;
if(error!=nil) {
NSLog(#"Unresolved error %#,%#.", error, [error userInfo]);
}
}
} else {
printf("Adaptor not ready %d, %d\n", frameCount, j);
[NSThread sleepForTimeInterval:0.1]; //Prevents system overload but causes lag.
}
j++;
}
if (!append_ok) {
printf("Error appending image %d times %d\n, with error.", frameCount, j);
}
}
- (void)saveVideoWithTrack:(NSString *)AudioTrackPath {
NSLog(#"**************************************************");
//Finish the session:
[videoWriterInput markAsFinished];
[videoWriter finishWritingWithCompletionHandler:^{
NSLog(#"Render complete."); ///Used to satisfy 64-bit devices
}];
sleep(1); //Required to avoid crash due to overload
NSLog(#"Render complete.");
//Audio File Addition
NSLog(#"Singing Tracks...");
AVMutableComposition *mixComposition = [AVMutableComposition composition];
//NSString *bundleDirectory = [[NSBundle mainBundle] bundlePath];
//NSString *audio_inputFilePath = [bundleDirectory stringByAppendingPathComponent:#"30secs.mp3"];
NSURL *audio_inputFileUrl = [NSURL fileURLWithPath:AudioTrackPath];
//Get the final video path
NSURL *video_inputFileUrl = [NSURL fileURLWithPath:videoOutputPath];
//Create the final video amd export as MOV
NSString *outputFilePath = [documentsDirectory stringByAppendingPathComponent:#"final_output.mov"];
NSURL *outputFileUrl = [NSURL fileURLWithPath:outputFilePath];
if ([[NSFileManager defaultManager] fileExistsAtPath:outputFilePath]) {
[[NSFileManager defaultManager] removeItemAtPath:outputFilePath error:nil];
}
CMTime nextClipStartTime = kCMTimeZero;
AVURLAsset *videoAsset = [[AVURLAsset alloc] initWithURL:video_inputFileUrl options:nil];
CMTimeRange video_timeRange = CMTimeRangeMake(kCMTimeZero, videoAsset.duration);
AVMutableCompositionTrack *a_compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
[a_compositionVideoTrack insertTimeRange:video_timeRange ofTrack:[[videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:nextClipStartTime error:nil];
//nextClipStartTime = CMTimeAdd(nextClipStartTime, a_timeRange.duration);
AVURLAsset *audioAsset = [[AVURLAsset alloc]initWithURL:audio_inputFileUrl options:nil];
CMTimeRange audio_timeRange = CMTimeRangeMake(kCMTimeZero, audioAsset.duration);
AVMutableCompositionTrack *b_compositionAudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
[b_compositionAudioTrack insertTimeRange:audio_timeRange ofTrack:[[audioAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:nextClipStartTime error:nil];
AVAssetExportSession *_assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetHighestQuality];
//Supported file types include...
//NSLog(#"Supported file types are %#", [_assetExport supportedFileTypes]);
_assetExport.outputFileType = #"com.apple.quicktime-movie";
_assetExport.outputURL = outputFileUrl;
[_assetExport exportAsynchronouslyWithCompletionHandler:^(){
NSString *exported = [[NSString alloc] initWithString:[outputFileUrl path]];
[self sendToCameraRoll:exported];
}];
NSLog(#"Saved to camera roll. %#", outputFilePath);
}
- (void)saveVideo {
NSLog(#"**************************************************");
//Finish the session:
[videoWriterInput markAsFinished];
[videoWriter finishWritingWithCompletionHandler:^{
NSLog(#"Finished"); //Used to satisfy 64-bit systems.
}];
sleep(1); //Required to avoid system crash
NSLog(#"Render complete.");
[self sendToCameraRoll:videoOutputPath];
NSLog(#"Saved to camera roll. %#", videoOutputPath);
}
- (CVPixelBufferRef) pixelBufferFromCGImage: (CGImageRef) image {
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,
[NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey,
nil];
CVPixelBufferRef pxbuffer = NULL;
CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault,
width,
height,
kCVPixelFormatType_32ARGB,
( CFDictionaryRef) options,
&pxbuffer);
if (status != kCVReturnSuccess){
NSLog(#"Failed to create pixel buffer");
}
CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
size_t bytesPerRow = 4*width; //BytesPerRow 4 bytes each pixel.
CGContextRef imageContext = CGBitmapContextCreate(pxdata, width,
height, 8, bytesPerRow, rgbColorSpace,
kCGBitmapByteOrderDefault | kCGImageAlphaNoneSkipFirst);
CGContextDrawImage(imageContext, CGRectMake(0, 0, width, height), image);
CGColorSpaceRelease(rgbColorSpace);
CGContextRelease(imageContext);
CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
NSLog(#"bPR: %zd", pxbuffer);
return pxbuffer;
}
- (void)viewDidLoad {
[super viewDidLoad];
//[self initFunction:nil width:1138 height:640 fps:25];
//[self initFunction:nil width:910 height:512 fps:25];
//[self initFunction:nil width:400 height:200 fps:25];
[self initFunction:nil width:50 height:50 fps:25];
//find url...
//get pixel data...
//loop through writing it from the pixel data
for (int i = 1; i <= 50; i++) {
//NSString *string = [NSString stringWithFormat:#"/Users/Lewis/Desktop/sequence/%06d.jpg", i];
//NSString *string = [NSString stringWithFormat:#"/Users/Lewis/Desktop/ThisIsATest/ThisIsATest/image1.jpg"];
//NSString *string = [NSString stringWithFormat:#"/Users/Lewis/Desktop/ThisIsATest/ThisIsATest/image2.jpg"];
//NSString *string = [NSString stringWithFormat:#"/Users/Lewis/Desktop/mini.jpg"];
NSString *string = [NSString stringWithFormat:#"/Users/Lewis/Desktop/50x50.jpg"];
NSLog(#"%#", string);
[self addFrameFromURL:string];
}
[self saveVideo];
}
Edit: All images work if they are 400 x 200.
All also work at 800 x 400, 1600 x 800.
600 x 300 does not work.
Possibly aspect ratios?

Answer 1

Solved this issue using specific dimensions. AVAssetWriter only supports specific "valid" aspect ratios.