On Sat, Aug 22, 2020 at 01:35:28PM -0700, yunhua li wrote: > HI Alan Thanks for your response. > > What is the communication speed of the camera? 480 Mb/s (USB-2), 5000 > Mb/s (USB-3) or something else? And how much data does the camera send > for each frame? > It is 5000Mb/s (USB 3.0), each video frame is about 2880000, 30 fps. So at 500 MB/s, and with less than 5 MB/frame, the expected transfer time for each frame is under 10 ms. 30 frames per second should be fine. > > 20 - 200 seconds? That's an awfully long latency. Much longer than you > would expect from random fuctuations; it indicates that something is > going badly wrong. > Sorry it is 0.02 ~ 0.2 seconds delay, when image got corrupted, Okay, that's more like what one might expect. > > It depends on what other devices are attached to the USB bus. They may > or may not require some reserved bandwidth. > There is no other USB device connected to the system. > if no other USB device, and no Isochronous transaction, Bulk > transaction (This camera) should be able to use all bandwidth, am I > correct? Yes, that's right. Alan Stern
