Correctly configuring QoS across your network and making sure that all packets are properly tagged is a good start. Depending on the quality of the video that you need, you may also find that setting defaults on the bandwidth of endpoints to lower settings works well enough for your needs, so you're not making 4K video calls if it's not necessary. In many cases 720P or 1080P may be all that is required.
Also remember that in a call, the audio quality can be much more important (and the most sensitive to jitter, latency and packet loss), where video can often suffer a bit of stutter or pixelation without any serious consequences.
It can be a fine balancing act, and what is possible will all depend on what your specific requirements are.
Wayne
Please remember to mark helpful responses and to set your question as answered if appropriate.
