objective c - Video capture with 1:1 aspect ratio in iOS

Question

I want to capture videos with an iOS camera with 1:1 aspect ratio.

I tried with UIImagePickerController, but it doesn't provide changing aspect ratio. Could anyone give me ideas?

Additionally, the iPhone app "Viddy" provides 1:1 aspect ratio video capturing:

Answer 1

AVCaptureVideoPreviewLayer *_preview = [AVVideoCaptureVideoPreviewLayer layerWithSession:_session];

_preview.frame = CGRectMake(0,0,320,320);
_preview.videoGravity = AVLayerVideoGravityResizeAspectFill;



NSDictionary *videoSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                               AVVideoCodecH264, AVVideoCodecKey,
                               [NSNumber numberWithInt:320], AVVideoWidthKey,
                               [NSNumber numberWithInt:320], AVVideoHeightKey,
                               AVVideoScalingModeResizeAspectFill,AVVideoScalingModeKey,
                               nil];

self.videoInput = [AVAssetWriterInput assetWriterInputWithMediaType: AVMediaTypeVideo
                                                     outputSettings: videoSettings];


self.videoInput.transform = CGAffineTransformMakeRotation(M_PI);
if([_writer canAddInput:_videoInput]) // AVAssetWriter *_writer
    [_writer addInput:_videoInput];

Note:

_preview's videoGravity and the videoSettings AVVideoScalingModeKey should be same to get the output as 320 x 320.