USB Capture Latency Test

Testing environment

  • CPU: Intel Xeon E5-1620 v3
  • RAM: 8GB RAM
  • OS: windows 10 64-bit

Testing method

The video source is the Macbook. It outputs via HDMI to a splitter. The Output 1 port of the splitter is connected to a monitor and Output 2 is connected with a USB Capture HDMI. The dongle captures the video and feeds to the Macbook via USB 3.0. The capture software is Capture Express V2.1 developed by Magewell. A stopwatch application developed by Magewell is running on the Macbook. The smallest unit it can measure is 0.001 second, which is 1 ms. The original and captured video are displayed on the monitor. See the picture below. Screenshots are made and calculation is done according to the data on the screenshots. The same test is done for 6 times to get 6 results in order to be more accurate.

20160222USB-Capture-HDMI-latency-test

Causes of Error

  1. The operation of screenshots
  2. The latency is very small, which is measured by milli-seconds.
  3. The processing latency of all the connected hardware

Result Record

source format latency(ms) minimal value
1 2 3 4 5 6
1080p@60pHz 79 78 47 63 60 63 47
1080p@50pHz 62 78 109 93 62 62 62
640x480@60pHz 78 110 46 78 62 91 46
720x480@60pHz 108 81 62 94 78 62 62
720x576@50pHz 62 125 108 79 78 94 62
720x576@60pHz 78 78 63 79 92 62 62
800x600@60pHz 47 94 78 78 78 72 47
1024x768@60pHz 110 94 62 62 78 77 62
1152x864@60pHz 110 109 62 79 94 94 62
1280x768@60pHz 78 78 78 94 78 78 78
1280x800@60pHz 125 109 62 62 125 109 62
1280x960@60pHz 94 63 94 94 78 109 63
1280x1024@60pHz 79 109 109 62 31 63 31
1440x900@60pHz 62 46 78 78 110 63 46
1600x900@60pHz 62 63 63 63 94 63 62
1680x1050@60pHz 94 110 46 94 78 63 46
1080i@30iHz 74 60 124 90 78 78 60
720p@50pHz 78 78 63 78 108 63 63
648p@50pHz 125 109 63 94 63 79 63

Conclusion

Please refer to the minimal value. Considering the error, the actual capture latency should be less than the minimal value.