What frame size dimensions does the encoder use with hardware cropping?
If hardware cropping is available, the encoder uses it as the default cropping method. If you have chosen to match the frame size of the source video, the encoder automatically uses 640 x 480 pixels as the width and height of the source video and then applies cropping to those dimensions. If that fails (for example, if the crop margins are not valid), then the encoder applies cropping to the input size specified on the capture card.