How can we roughly calculate the latency introduced by FX3/CX3 in the video streaming design?
The latency can be estimated roughly using the information in the following table.
FX3 48KB Buffer Filling Time
USB (~ 300 MBps)
The results in this table are obtained based on the following:
- CX3: input:1080p@30 fps, RAW10 output: USB3.0. The latency time is the time between the input and the output in this case.
- FX3: input:1080p@30 fps, 32-bit parallel output: USB3.0. The latency time is the time between the input and the output in this case.
- We considered 1080p@30 fps for calculation in this case. Each line will take 33.33 ⁄1080 = 30 .
- The number of lines for the 48-KB buffer should be 48 ∗ 1024⁄(1920 ∗ 10/8) = 20.48
- Buffer filling time should be line time* No. of lines in a buffer = 30 ∗ 20.48 = 614.4μs
For other resolutions, frame rates, and buffer size configuration, the results are different. However, it can be calculated in the same way as shown above.