avassetwriter

I have seen this question asked many times in different forms both here and in other forums. Some of the questions get answered, some do not. There are a few where the answerer or author claims to have had success. I have implemented the examples from those that claim success, but have yet to see the same results. I am able to successfully use AVAssetWriter (and AVAssetWriterInputPixelBufferAdaptor) to write image data and audio data simultaneously when the sample buffers are obtained from an AVCaptureSession. However, if I have CGImageRef's that were generated in some other way, and build a

I have an app which encodes videos in different ways and saves it to Photos library - it can cut specific time range, add pictures, text, etc. Everything is working perfectly till I try to encode video 120+ fps. The problem is that video appears to be slow-motioned and I don't pursue that goal at all. Here I found out about property for AVAssetWritterInput which is called AVVideoExpectedSourceFrameRateKey , but the problem is that when I try to apply this parameter to my AVAssetWritterInput , I'm getting this error: *** Terminating app due to uncaught exception 'NSInvalidArgumentException',

I am encoding a video using cocoa for OSX (with AVAssetWriter) in h264. This is the configuration: // Configure video writer AVAssetWriter *m_videoWriter = [[AVAssetWriter alloc] initWithURL:[NSURL fileURLWithPath:@(outputFile)] fileType:AVFileTypeMPEG4 error:NULL]; // configure video input NSDictionary *videoSettings = @{ AVVideoCodecKey : AVVideoCodecH264, AVVideoWidthKey : @(m_width), AVVideoHeightKey : @(m_height) }; AVAssetWriterInput* m_writerInput = [[AVAssetWriterInput alloc] initWithMediaType:AVMediaTypeVideo outputSettings:videoSettings]; // Add video input into video writer [m

I have successfully created video from uiimages using AVAssetWriter. But as soon as the writer starts writing video theres a sudden rise in the memory allocation in the instruments. The spike in the memory allocation changes from 3-4 MB to 120MB and then cools off. I have used the following code for this... -(void)writeImageAsMovie:(NSArray *)array toPath:(NSString*)path size:(CGSize)size { NSMutableDictionary *attributes = [[NSMutableDictionary alloc]init]; [attributes setObject:[NSNumber numberWithUnsignedInt:kCVPixelFormatType_32ARGB] forKey:(NSString*)kCVPixelBufferPixelFormatTypeKey];

What's the right way to add an image overlay to a video created with AVAssetWriter? It's possible to do so with AVAssetExportSession, but this question is about how to do so with AVAssetWriter so there is more control over the quality and output. There are two scenarios: 1) Simple: Add single overlay that is present the entire duration of the video (similar to a watermark). 2) Complex: Add different overlays that animate in and out of the video at different times (similar to using AVVideoCompositionCoreAnimationTool). Tim Bull There's a lot of different approaches to this and the correct

We are trying to understand how to control/specify the frame rate for videos that we are encoding with AVAssetReader and AVAssetWriter . Specifically, we are are using AVAssetReader and AVAssetWriter to transcode/encode/compress a video that we have accessed from the photo/video gallery. We are able to control things like bit rate, aspect ratio changes, etc., but cannot figure out how to control the frame rate. To be specific, we'd like to be able to take as input a 30 FPS video that's 5 minutes long and emit a 5 minute video at 15 FPS. Our current loop that processes sample buffers is: