Screen and quality

[FranckB]

a question about how OBS works.
Does the quality of the screen influence the quality of the video? as is the case when capturing an image.
In addition, the stream is captured at the card level or on screen display.
In the hypothesis of the second case, could we have a virtual flow? on an output of a non-physical screen and which would be captured

 

[koala]

For display capture and game capture, OBS reads the frame buffer of the GPU that is currently being sent to the logical monitor by Windows.
This is two processing steps before it's actually going out to the physical monitor.
One additional processing step is from Windows and this is not captured by OBS. It's Windows postprocessing like night mode (reduce blue color).
The other additional processing step is by the graphics driver and is not captured by OBS as well: this is optional "color enhancement" by common graphics drivers and some optional graphics driver features like Dynamic Super Resolution from Nvidia. For DSR, Windows, all apps, and OBS itself, only sees and paints on/reads from a virtual high resolution monitor, not the real lower resolution of the physical monitor.