Auto adjusting screen resolution to video resolution

[Computer Nerd Kev]

Hello,

It seems funny to me that most video playing software encourages you to view low resolution video in such a way that it is either stretched terribly over the user's standard resolution, or otherwise shown in the small area of ones screen which contains the correct number of pixels.

I personally would much rather set my monitor/GPU to match the video resolution and not be forced to put up with the graphical troubles caused by this.

Now I know that with standard hardware, it may not be possible to exactly match the resolution of every video, however I expect that close enough should still give much better results.

So my question is:
Does any video software exist which offers the automatic changing of screen resolution to suit the video being played.

Furthermore, I would love to hear what others think of this idea (whether such a feature exists in a program or not).


By the way, I should point out that I still use a CRT monitor.
I know that flat screen monitors often have strange ways of dealing with low resolutions.

[guns1inger]

No. And it won't actually solve your problem. Whichever way you do it, you will always have to expand or contract the video to match the screen size. Take a monitor that has a native resolution of 1600 x 1200, and force the resolution of your card down to 800 x 600. What you get a screen full of soft, enlarged pixels. Now play a video that has a resolution of 800 x 600 and you get an enlarged, soft looking video. Put the resolution back to 1600 x 1200 and play the same video. You now have a choice. You can keep the video at 800 x 600, and not fill the screen. The video will be as sharp as it was encoded to be. You can enlarge the video to fill the screen, and with decent upscaling algortithms, get a pretty good picture.

Now try the same thing with a 360 x 480 clip. You can't - no video card supports resolution so low.

Now what happens when you try to change your resolution to 620 x 284. First, you can't. Again, there is a small and finite number or resolutions allowable, and most do not match common video/film resolution at all. But assuming they did have a resolution to match, you then have the issue that your screen is 4:3, but the movie is 2.35 : 1. You can't change the shape of the monitor, so your resolution will fill the screen, giving you distorted, stretched video.

Digital video works the way it does because that is the best design. Your proposed solution doesn't solve your problem, and adds a whole lot of new ones to the equation, without bringing any benefits.

Your problem is watching low quality, low resolution, crappy video. Don't.

Or if you must, find a really old computer that still supports 640 x 480 or 800 x 600 resolutions, and get an old monitor to match, and use that for watching your low grade videos.

[Computer Nerd Kev]

Your problem is watching low quality, low resolution, crappy video.

Quite right.

Don't.

Tough, those videos take up too much HDD space as it is.

Or if you must, find a really old computer that still supports 640 x 480 or 800 x 600 resolutions, and get an old monitor to match, and use that for watching your low grade videos.

Exactly what I've got.
Nvidia Geforce 4 Ti GPU and Samsung SyncMaster 750s monitor, if you want to look them up for proof (those computer specifications aren't a joke).


That "soft" looking video you were talking about was part of what I meant by my last sentence. I assume that such a CRT display as mine should be happy with low resolutions and I know well that it works well at 640x480.

Now when we talk about impossible resolutions and aspect ratios. I feel that attempting to get as close as possible and then scaling to fit, would still give a better result.

[jagabo]

No matter what you do, if you enlarge a small video to full screen it will get fuzzy or blocky.

[Computer Nerd Kev]

No matter what you do, if you enlarge a small video to full screen it will get fuzzy or blocky.

But if you are able to match screen resolution to your video resolution, the video will not need to be enlarged to fit full screen.

[jagabo]

No matter what you do, if you enlarge a small video to full screen it will get fuzzy or blocky.

But if you are able to match screen resolution to your video resolution, the video will not need to be enlarged to fit full screen.

Yes, it will. Except it will be the monitor doing it, not the graphics card. A high res CRT displaying a 640x480 frame will show obvious blank lines between the 480 scanlines and blocky pixels along the width.

[edDV]

Backing into history, it is possible to do what you want with a multiscan CRT monitor.

You need to manually adjust vertical and horizontal scan frequencies to match the file being played.

This was more successful with front projectors (i.e Cinema) where the projector gets adjustment for each movie.

Computer monitors tend to have an optimal resolution and all video is converted for display at that resolution.

[Computer Nerd Kev]

OK, so when a monitor encounters any resolution other than the few which it supports, it simply resizes the video to cover one of it's own resolutions.

I see now that my monitor can only give the resolutions 640x480, 720x400, 800x600 and 1024x768, each at various frequencies.

So I could never view low resolution video full screen by changing it's resolution without either finding a monitor which will take whatever you throw at it, or gathering up a bunch of old monitors and switching between them depending on which video I want to watch.

I now fear that I may one day try that multiple monitor set up,
but thanks for your help all the same.

[jagabo]

OK, so when a monitor encounters any resolution other than the few which it supports, it simply resizes the video to cover one of it's own resolutions.

That's true for fixed pixel displays like LCD and plasma monitors. Some also have an option to display a smaller frame at its original size but centered on the screen.

CRTs are different. They change the way the electron beam is scanned across the face of the CRT. If the monitor is optimized to display 1280x960 and you send it a 640x480 frame it will draw 480 scan lines instead of 960. But it will do it by skipping every other scan line. There will be obvious black gaps between each scanned line (the electron beam is usually a little thicker than a single scan line so the dark gap may not be a full pixel thick). Since it can resolve 1280 pixels across its width each pixel in the 640 pixel wide image will be doubled horizontally. If you look closely it will look grainy.

See if your graphics card or media player has sharper options for scaling (say, bicubic instead of bilinear) or an adjustable sharpness setting.





But keep in mind that sharpening the picture will also enhance the compression artifacts.

[Computer Nerd Kev]

Thanks for the screenshots and explanation.

I thought at the start that there would be gaps, however I did not know that CRT monitors dealt with the horizontal resolution that way.

To be honest I don't think I'll be trying to do this if there is no video player which changes resolution automatically. It is simply too hard to use the GUIs at such low resolutions (often 320x240 and the like).

[pandy]

MPC is able to change video resolution (limited way), CRT is flexible enough to display ANY resolution if requirement for Min/Max V&H frequency are within limits - also Nvidia driver makes possible to create own - UNIQUE video modes - this is WHY I LOVE CRT (second reason is interlace - on CRT in interlace mode it looks normal).

[Computer Nerd Kev]

Great!
I tried launching a video in VLC from the command line after changing screen resolutions and found that it displayed completely off centre, so it's great to find that there is a way to watch low res video at a matching resolution.

Of course it would be much better if it could do this automatically. However I doubt that, with the rise of flat screen monitors, such a feature will be added to any existing player in the future.

Still, I got a book on programming a while ago so you never know...