Frame rate cannot exceed 30fps

[imguoguo]

When using ffmpeg on devices like macOS to execute ffmpeg -f avfoundation -i "0" -hide_banner to check, it can be found that the maximum supported frame rate at 1920x1080 resolution is 50fps, detailed output is as follows:

> ffmpeg -f avfoundation -i "0" -hide_banner 
// ...
[avfoundation @ 0x123456789] Selected framerate (29.970030) is not supported by the device.
[avfoundation @ 0x123456789] Supported modes:
[avfoundation @ 0x123456789]   640x480@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   640x480@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   640x480@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   640x480@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   640x480@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   640x480@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   640x480@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   640x480@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   640x480@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   720x480@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   720x480@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   720x480@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   720x480@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   720x480@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   720x480@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   720x480@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   720x480@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   720x480@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   720x576@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   720x576@[25.000000 25.000000]fps
[avfoundation @ 0x123456789]   720x576@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   720x576@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   720x576@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   720x576@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   720x576@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   720x576@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   720x576@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   800x600@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   800x600@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   800x600@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   800x600@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   800x600@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   800x600@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   800x600@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   800x600@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1024x768@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   1024x768@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   1024x768@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   1024x768@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1024x768@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1024x768@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1024x768@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1280x720@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   1280x720@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   1280x720@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   1280x720@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1280x720@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1280x720@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1280x720@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1280x960@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   1280x960@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   1280x960@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   1280x960@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1280x960@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1280x960@[15.000015 15.000015]fps
[avfoundation @ 0x123456789]   1280x960@[8.000000 8.000000]fps
[avfoundation @ 0x123456789]   1280x1024@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   1280x1024@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   1280x1024@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   1280x1024@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1280x1024@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1280x1024@[15.000015 15.000015]fps
[avfoundation @ 0x123456789]   1280x1024@[8.000000 8.000000]fps
[avfoundation @ 0x123456789]   1360x768@[60.000240 60.000240]fps
[avfoundation @ 0x123456789]   1360x768@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   1360x768@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   1360x768@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1360x768@[10.000000 10.000000]fps
[avfoundation @ 0x123456789]   1360x768@[15.000015 15.000015]fps
[avfoundation @ 0x123456789]   1360x768@[8.000000 8.000000]fps
[avfoundation @ 0x123456789]   1920x1080@[50.000000 50.000000]fps
[avfoundation @ 0x123456789]   1920x1080@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   1920x1080@[25.000000 25.000000]fps
[avfoundation @ 0x123456789]   1920x1080@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   1920x1080@[10.000000 10.000000]fps
    Last message repeated 1 times
[avfoundation @ 0x123456789]   1920x1080@[5.000000 5.000000]fps
[avfoundation @ 0x123456789]   2560x1440@[30.000030 30.000030]fps
[avfoundation @ 0x123456789]   2560x1440@[25.000000 25.000000]fps
[avfoundation @ 0x123456789]   2560x1440@[20.000000 20.000000]fps
[avfoundation @ 0x123456789]   2560x1440@[10.000000 10.000000]fps
    Last message repeated 1 times
[avfoundation @ 0x123456789]   2560x1440@[5.000000 5.000000]fps

However, when using the browser, the frame rate is only 30fps. You can check this using the following console information.

> document.querySelector('video').srcObject.getVideoTracks()[0].getSettings()

{
    aspectRatio: 1.7777777777777777, 
    deviceId: 'xxxxxx', 
    frameRate: 30.000030517578125, 
    groupId: 'xxxxxx', 
    height: 1080,
    ...
}

Settings to set the frame rate may need to be added.