Windows Media Foundation UVC 8百万像素视频流

Question

I'm investigating an issue with an in-house developed app using WMF to capture UVC data from a Cypress FX3 device. The stream is generated from a test pattern generator fed from an FPGA to the FX3. For a frame size of 1920x1080 (@30FPS), the frame capture works fine. For a frame size of (say) 3264x2448 (at <8FPS to meet throughput restrictions) the app is getting stuck during the ReadSample(). It does appear data is being received as the data image pattern can be seen in memory. Device enumeration looks ok ie the reported descriptors look to be correct and SelectFormat() is set accordingly.

Are there any restrictions on frame size?

Answer 1

I see that problem with your hardware is very specific and can be related with hardware part. The frame size - 3264x2448 is very huge. I have experience with Logitecn HD Pro Webcam C920 and I can get max frame size 2304x1536 at 2 FPS and RGB24. If you have connected via USB then it can be problem to transmit it via USB bus (especially for USB2). You must know that Windows Media Foundation is engine of the media part of Windows - for example WindowsStore can work only with Media Foundation. More over, Windows 10 Includes encoder and decoder for HEVC (H265) video and supports 4K and 8K in native, but playing video and working with live video via USB has some difference.