How does my projector downsample the input resolution into its native resolution?

Question

I have a projector that has a maximum input resolution of 1920x1080 and a native resolution of 800x480.

If I plug it into my computer which is sending it a 1920x1080 signal, what is it doing to display it at 800x480? The two aspect ratios are not multiples of each other so simply downscaling the images coming from the input doesn't make sense.

The main reason I ask is that I want to display an image of size exactly 800x480 through my computer, on the projector. But I'm unable to achieve this because my computer is outputting a 1920x1080 signal.

Thanks for any clarification.

Answer 1

Your projector uses an algorithm to reduce the larger image size it is being sent to the lower resolution. It can achieve this be dropping lines of resolution and/or blending colors together. This will result in loss of image quality. As for the aspect ratio, depending on the projector's algorithm, it will wither fit the image to the projectors max, or simply give you a letterbox version - like movies on a TV. You would need to check your projector's manual to see what options are available.

You didnt say what operating system you are using, so I am going to assume Windows 10. Windows has a minimum height of 800 x 600 pixels. As far as I know, you cannot go below that minimum.

However, you might be able to do a resolution of 1000 x 600, which is a multiple of 1.25 of the projectors resolution. This should scale easily, with minimum loss of quality. Again, you didnt mention your OS or GPU, however you can simply google for how to create custom resolutions for your OS and GPU and you should be good to go.