ofxEdsdk - video resolution and framerate

I’m testing ofxEdsdk using a Canon EOS 5D Mark III 1. I don’t see any function to set the width and height of the video and i don’t know why, using the example inside the addon, my camera records at 960x640, 28fps. The right resolution should be 1080p. Did anyone have the same problem?

Assuming you are using the camera’s USB 2.0 connctor, you the limit may be due to the maximum throughput of USB2.0, which is has a signal rate of 480Mbit/sec, actual throughput is typically much lower than that, wikipedia claims the typical throughput is only 280Mbit/s, but I’m pretty sure many video streaming devices use a more efficient use of the protocol and maybe able to achieve close to 400Mbit/s.

960x640 pixels x 3 channels x 8 bits/pixel x 28 fps = 412876800 bits/sec , ~394Mbit/sec.

1080p streaming over a USB2.0 connection is only possible with compression, typically H264, which adds some latency as it must be compressed on the device, transferred, then decompressed on the host computer.

If you want 1080p streaming from that camera, you’ll need to go with a HDMI capture device, which typically use USB3.0, thunderbolt, or PCI Express which would be able to support the throughput necessary. Take a look at the blackmagic product line for these devices.

Thanks a lot TimS! It’s what i thought about the USB2.0 problem, but now you confirmed my doubts. Now i try some way to get the 1080p.