Question / Help Recording screen getting cut of

[Dashin-Dunnart]

Hey I’m I just got obs and I’m super new to computers in general so sorry if this is a stupid question. I’m playing games at 1920x1080 and recording at 1280x720 which seems to work fine for apex legends which was the game I was testing settings on. But I tryed to record footage of the new ghost recon game and when I changed the record resolution to 720 it cuts of the screen in the recording window. I can get get it to display the full screen of the game if I change it to 1080 but then my games takes massive frame drops and the footage looks terrible. Any thing I could try to fix this? And is playing games in 1080 and recording in 720 a problem? Should I be be matching these resolutions? Anyway sorry again if these are silly questions, like I said super new to this stuff so bare with me as you will probably be seeing a lot of these sorts of question haha, cheers.

 

[koala]

OBS is not just a recording software. It doesn't just grab your screen and writes it as video to harddisk.
Instead, it takes any number of graphical sources, composites them and writes the composited video to harddisk (or stream). This compositing always takes place, even if you only use a single capture source.
To composite, it has to project (draw) each source frame by frame onto a canvas, layering them, and resizing them in the process. Then the canvas with the composited video frames is taken, encoded frame by frame and written to your output.

Now you can see where computing power is required, and where you can do any resizing. Compositing takes place on the GPU. The canvas of OBS is a hidden framebuffer on the GPU, and the larger you set the canvas, the higher the resource demands. If you get frame drops if you change the canvas from 1280x720 to 1920x1080, your GPU isn't powerful enough to display the game and at the same time composite the video for OBS with the higher resolution.
Resizing a source on the GPU doesn't cost resources, but compositing and processing filters does.
You can set OBS canvas to 1280x720 and fit the game capture source (sized 1920x1080, if you play your game in that resolution) to the canvas just fine. It's actually the least resource intensive variant, so do it.

The data flows this way: game (1920x1080) -> game capture source (1920x1080) -> resize (1280x720) -> composite on canvas (1280x720) -> output (1280x720).

If you choose a canvas of 1920x1080), it is this:
game (1920x1080) -> game capture source (1920x1080) -> composite on canvas (1920x1080) -> resize (1280x720) -> output (1280x720).
Compositing in 1920x1080 instead of 1280x720 needs 2.25 times the resources, since 1080p has 2.25 times the pixels.

You can resize by changing the size of a source on the canvas (in the preview), and you can resize the output video (Settings->video). This takes place on the GPU and costs almost no resources. A third resize option exists in the properties of the encoder. Don't use this, because this resizing takes place on the CPU and is very inefficient. This costs a large amount of resources.