CVMetalTextureCacheCreateTextureFromImage returns -6660 on macOS 10.13

macos, metal, objective-c

Solution

I've come across the same issue, the problem was not asking for Metal compatibility when configuring the `AVCaptureVideoDataOutput`. I guess the system started to check this in macOS 10.13, possibly to apply some optimization when not requested.

The solution was to add the `kCVPixelBufferMetalCompatibilityKey` to the `videoSettings` property of `AVCaptureVideoDataOutput`.

In Objective-C:

outputCapture.videoSettings = @{
  /* ... */
  (NSString *)kCVPixelBufferMetalCompatibilityKey: @YES
};

In Swift:

outputCapture.videoSettings = [
  /* ... */
  kCVPixelBufferMetalCompatibilityKey as String: true
]

I think this warrants a radar, to ask Apple to at least print a warning message when this occurs. I'll update this if I get to it.

Problem

I'm recording the screen from my iPhone device to my Mac. As a preview layer, I am collecting sample buffers directly from an `AVCaptureVideoDataOutput`, from which I'm creating textures and rendering them with `Metal`. The problem I'm having is that code that worked in macOS prior to `10.13` stopped working after updating to `10.13`. Namely, ``` CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(_currentSampleBuffer); if (!imageBuffer) return; CVPixelBufferLockBaseAddress(imageBuffer,0); size_t width = CVPixelBufferGetWidth(imageBuffer); size_t height = CVPixelBufferGetHeight(imageBuffer); CVMetalTextureRef metalTexture = NULL; CVReturn result = CVMetalTextureCacheCreateTextureFromImage(nil, self.textureCache, imageBuffer, nil, self.pixelFormat, width, height, 0, &metalTexture); if (result == kCVReturnSuccess) { self.texture = CVMetalTextureGetTexture(metalTexture); } ``` Returns `result = -6660`, which translates to a generic `kCVReturnError`, as can be seen on the official Apple docs, and the `metalTexture = NULL`. The pixel format I'm using is `MTLPixelFormatBGRG422` since the samples coming from the camera are `2vuy`. As a workaround to creating `metalTexture` from `sampleBuffer`, I am now creating an intermediate `NSImage` like so: ``` CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(_currentSampleBuffer); NSCIImageRep *imageRep = [NSCIImageRep imageRepWithCIImage:[CIImage imageWithCVImageBuffer:imageBuffer]]; NSImage *image = [[NSImage alloc] initWithSize:[imageRep size]]; [image addRepresentation:imageRep]; ``` and creating a `MTLTexture` from that. That is obviously a subpar solution to using `CVMetalTextureCacheCreateTextureFromImage` directly. Once again, the code in question works perfectly fine in `macOS < 10.13`, I'd like to know if anyone has similar issues, and if so, do you have any ideas how to overcome this?

Original source