I'm running into hard crashes (EXC_BAD_ACCESS) when calling CIContext.writeHEIF10Representation or CIContext.heif10Representation from multiple threads. By contrast, concurrent access to writeHEIFRepresentation works fine.
Does anyone know any other way to write a CIImage to 10-bit HEIF? I've tried several alternatives using CVPixelBuffer and MTLTexture without success.
While I've filed a report through Feedback Assistant, I'm looking for a workaround. Writing thousands of 10-but hdr heif images within a single thread is an absolute throughput killer, whereas I can write any other image format without concurrency issues.
Thanks!
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FrankSchlegel
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mallman
Add a CommentAre you using the same
CIContextin all threads? And can you please post a screenshot of the stack when the crash happens?Hi Frank. I have tried using one
CIContextper thread as well as sharing one across threads. I've posted a dead simple Xcode workspace illustrating the crash with simple Swift and Objc apps at https://github.com/mallman/ConcurrentCoreImageHEIF10. Since there are many relevant threads with different stack traces when the app crashes, a screenshot of a single thread's stack trace really isn't very informative. I hope the project is helpful.