[bug] encode frames is always 0/0 in stats dialog

[walker-WSH]

Operating System Info

Windows 11

Other OS

WIN

OBS Studio Version

31.0.0-rc1

OBS Studio Version (Other)

31

OBS Studio Log URL

none

OBS Studio Crash Log URL

No response

Expected Behavior

while recording or streaming, on stats dialog, drop encoded frame and total encoded frame can be displayed normally

Current Behavior

encoded frame is always 0

Steps to Reproduce

1. settings window -> outpout -> streaming/recording tab -> Rescale Output enabled, select NVENC OR QSV encoder
2. start streaming or recording
3. open stats dialog, check encoding frame field (always 0)
   ...

Anything else we should know?

reason:

1. for stats dialog, it is displaying variables in obs_get_video();
2. for encode thread, when to increase frames variable, the video_t is not the object returned by obs_get_video. it is modifying the temp video_t for gpu scale