Fails to compile with ffmpeg 5.0

[SoftExpert]

Building OpenCV fails when ffmpeg 5.0 is installed.

Description

Steps to Reproduce

1. install gocv module
2. build OpenCV with sudo make install inside ~/go/pkg/mod/gocv.io/x/[email protected]

Your Environment

• ffmpeg version 5.0-2ubuntu0~20.04.sav1
• Operating System and version: Ubuntu 20.04
• OpenCV version used: 4.5.5
• How did you install OpenCV? using sudo make install in the source folder of gocv
• GoCV version used: 0.30.0
• Go version: 18.0
• Did you run the env.sh or env.cmd script before trying to go run or go build? N/A

Additional info

I have commented on the OpenCV repo #21650, because I think it's related to OpenCV. Edit: First opened issue is #20147; subsequent ones are closed.

[SoftExpert]

With the following patch I was able to build OpenCV. The "Quick install" procedure does not allow to apply the patch, but the "Complete install" allows. At the end I was able to run the test and to obtain the confirmation that the libraries are OK:

go run ./cmd/version/main.go
gocv version: 0.30.0
opencv lib version: 4.5.5