How does vc.grab () get the latest frame without blocking

[feipengheart]

Description

I tried to stamp the time after the connection was successful and calculate the latest frame number by the difference between the time when the video frame was obtained and the time when the connection was successful. However, there are still errors that may cause several seconds of blocking. How can I solve this problem

Steps to Reproduce

Your Environment

• Operating System and version:
• OpenCV version used:
• How did you install OpenCV?
• GoCV version used:
• Go version:
• Did you run the env.sh or env.cmd script before trying to go run or go build?