Créez une vidéo à partir d'un tableau de UIImages et enregistrez la vidéo dans la bibliothèque iPhone. AVAssetLibrary + AVFoundation

-(void)convertimagetoVideo
{
/////////////setup OR function def if we move this to a separate function ////////////
//this should be moved to its own function, that can take an imageArray, videoOutputPath, etc...
NSError *error = nil;
//set up file manager, and file videoOutputPath, remove "test_output.mp4" if it exists...
//NSString *videoOutputPath = @"/Users/someuser/Desktop/test_output.mp4";
NSFileManager *fileMgr = [NSFileManager defaultManager];
NSString *documentsDirectory = [NSHomeDirectory()
stringByAppendingPathComponent:@"Documents"];
NSString *videoOutputPath = [documentsDirectory stringByAppendingPathComponent:@"test_output.mp4"];
//NSLog(@"-->videoOutputPath= %@", videoOutputPath);
//get rid of existing mp4 if exists...
if ([fileMgr removeItemAtPath:videoOutputPath error:&error] != YES)
NSLog(@"Unable to delete file: %@", [error localizedDescription]);
CGSize imageSize = CGSizeMake(400, 200);
//   NSUInteger fps = 30;
NSUInteger fps = 30;
//NSMutableArray *imageArray;
//imageArray = [[NSMutableArray alloc] initWithObjects:@"download.jpeg", @"download2.jpeg", nil];
NSMutableArray *imageArray;
NSArray* imagePaths = [[NSBundle mainBundle] pathsForResourcesOfType:@"png" inDirectory:nil];
imageArray = [[NSMutableArray alloc] initWithCapacity:imagePaths.count];
NSLog(@"-->imageArray.count= %i", imageArray.count);
for (NSString* path in imagePaths)
{
[imageArray addObject:[UIImage imageWithContentsOfFile:path]];
//NSLog(@"-->image path= %@", path);
}
//////////////    end setup    ///////////////////////////////////
NSLog(@"Start building video from defined frames.");
AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:
[NSURL fileURLWithPath:videoOutputPath] fileType:AVFileTypeQuickTimeMovie
error:&error];
NSParameterAssert(videoWriter);
NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
AVVideoCodecH264, AVVideoCodecKey,
[NSNumber numberWithInt:imageSize.width], AVVideoWidthKey,
[NSNumber numberWithInt:imageSize.height], AVVideoHeightKey,
nil];
AVAssetWriterInput* videoWriterInput = [AVAssetWriterInput
assetWriterInputWithMediaType:AVMediaTypeVideo
outputSettings:videoSettings];
AVAssetWriterInputPixelBufferAdaptor *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];
CVPixelBufferRef buffer = NULL;
//convert uiimage to CGImage.
int frameCount = 0;
double numberOfSecondsPerFrame = 6;
double frameDuration = fps * numberOfSecondsPerFrame;
//for(VideoFrame * frm in imageArray)
NSLog(@"**************************************************");
for(UIImage * img in imageArray)
{
//UIImage * img = frm._imageFrame;
buffer = [self pixelBufferFromCGImage:[img CGImage]];
BOOL append_ok = NO;
int j = 0;
while (!append_ok && j < 30) {
if (adaptor.assetWriterInput.readyForMoreMediaData)  {
//print out status:
NSLog(@"Processing video frame (%d,%d)",frameCount,[imageArray count]);
//CMTime frameTime = CMTimeMake((int64_t), (int32_t)2);
CMTime frameTime = CMTimeMake(frameCount*frameDuration,(int32_t) fps);
NSLog(@"seconds = %f, %u, %d", CMTimeGetSeconds(frameTime),fps,j);
append_ok = [adaptor appendPixelBuffer:buffer withPresentationTime:frameTime];
if(!append_ok){
NSError *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];
}
j++;
}
if (!append_ok) {
printf("error appending image %d times %d\n, with error.", frameCount, j);
}
frameCount++;
}
NSLog(@"**************************************************");
//Finish the session:
[videoWriterInput markAsFinished];
[videoWriter finishWriting];
NSLog(@"Write Ended");
}
-(void)CompileFilestomakeVideo
{
//set up file manager, and file videoOutputPath, remove "test_output.mp4" if it exists...
//NSString *videoOutputPath = @"/Users/someuser/Desktop/test_output.mp4";
NSString *documentsDirectory = [NSHomeDirectory()
stringByAppendingPathComponent:@"Documents"];
NSString *videoOutputPath = [documentsDirectory stringByAppendingPathComponent:@"test_output.mp4"];
//NSLog(@"-->videoOutputPath= %@", videoOutputPath);
//get rid of existing mp4 if exists...
AVMutableComposition* mixComposition = [AVMutableComposition composition];
NSString *bundleDirectory = [[NSBundle mainBundle] bundlePath];
//audio input file...
NSString *audio_inputFilePath = [bundleDirectory stringByAppendingPathComponent:@"30secs.mp3"];
NSURL    *audio_inputFileUrl = [NSURL fileURLWithPath:audio_inputFilePath];
//this is the video file that was just written above, full path to file is in --> videoOutputPath
NSURL    *video_inputFileUrl = [NSURL fileURLWithPath:videoOutputPath];
//create the final video output file as MOV file - may need to be MP4, but this works so far...
NSString *outputFilePath = [documentsDirectory stringByAppendingPathComponent:@"final_video.mp4"];
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];
_assetExport.outputFileType = @"com.apple.quicktime-movie";
//_assetExport.outputFileType = @"public.mpeg-4";
//NSLog(@"support file types= %@", [_assetExport supportedFileTypes]);
_assetExport.outputURL = outputFileUrl;
[_assetExport exportAsynchronouslyWithCompletionHandler:
^(void ) {
[self saveVideoToAlbum:outputFilePath];
}
];
/////THAT IS IT DONE... the final video file will be written here...
NSLog(@"DONE.....outputFilePath--->%@", outputFilePath);
//the final video file will be located somewhere like here:
///Users/caferrara/Library/Application Support/iPhone Simulator/6.0/Applications/D4B12FEE-E09C-4B12-B772-7F1BD6011BE1/Documents/outputFile.mov
////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////
}
- (void) saveVideoToAlbum:(NSString*)path {
NSLog(@"saveVideoToAlbum");
if(UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(path)){
UISaveVideoAtPathToSavedPhotosAlbum (path, self, @selector(video:didFinishSavingWithError: contextInfo:), nil);
}
}
-(void) video:(NSString *)videoPath didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo {
if(error)
NSLog(@"error: %@", error);
else
NSLog(@" OK");
}
////////////////////////
- (CVPixelBufferRef) pixelBufferFromCGImage: (CGImageRef) image {
CGSize size = CGSizeMake(400, 200);
NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,
[NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey,
nil];
CVPixelBufferRef pxbuffer = NULL;
CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault,
size.width,
size.height,
kCVPixelFormatType_32ARGB,
(__bridge CFDictionaryRef) options,
&pxbuffer);
if (status != kCVReturnSuccess){
NSLog(@"Failed to create pixel buffer");
}
CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);
CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(pxdata, size.width,
size.height, 8, 4*size.width, rgbColorSpace,
kCGImageAlphaPremultipliedFirst);
//kCGImageAlphaNoneSkipFirst);
CGContextConcatCTM(context, CGAffineTransformMakeRotation(0));
CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image),
CGImageGetHeight(image)), image);
CGColorSpaceRelease(rgbColorSpace);
CGContextRelease(context);
CVPixelBufferUnlockBaseAddress(pxbuffer, 0);
return pxbuffer;
}

Qui est tout simplement trop de code pour vérifier les erreurs. Assurez-vous que vous pouvez commencer l'exportation de la session, que vous avez vraiment obtenir pixel tampons pour vos images, que l'auteur est prêt pour recevoir plus de données que la mémoire tampon est ajoutée sans erreurs, que l'exportation de la session se termine avec succès et que le film de sortie de fichier existe et contient certaines données. Seulement alors vous pouvez essayer de l'enregistrer dans le système de l'album photo. Vérifier que toutes les informations d'erreur le long du chemin afin que vous sachiez où la chose se brise pour la première fois. (Autre chose, c'est que vous êtes tout simplement le code depuis le web et le coller ensemble, ce qui est tout simplement pas d'aller travailler pour AV de programmation.)