Playing 1080p video at 1366x768-does it downconvert to 720p?

[bigshotceo]

Here's my question: I have some 1080p mkv videos that I'd like to play back on my w4207 LCD tv. My video card is set is a 6800gt set at 1366 by 768 (the TV's recommended resolution). Will the video be converted to 768p by my media software (media player classic) and sent to the tv as 768p or will it be sent as 1080i? Also, if I play 1080i video, what resolution will it be sent to the tv as? Will the de-interlacing be done by my software or by the tv?

[guns1inger]

If you are outputting through VGA and your resolution is set to 1366 x 768 then you will only be sending 1366 x 768 to the TV. If you played back the 1080p source at 1080p you would see it go off the edges of the screen. You are effectively using your TV as a monitor, so it will respond as a monitor would.

[RickA]

Sorry if I am stepping on your thread bigshot. It is only in an effort to gain some clarity.

@ guns1inger, I understand part of what you are saying but if you could help clear up the other I would greatly appreciate it. I understand tv's overscan and that you can use one as a monitor. What confuses me is it sounds like you are saying he will get overscan outputting at 1080p but not if using 1366x768. So I'm wondering why it would do that in one case but not the other? I'm still firmly in the realm of SD and it may be some time before I dabble in HD, so trying to learn ahead of time. Thanks.

Cheers,
Rick

[jagabo]

He's saying if the computer insisted on decoding the 1920x1080 video pixel for pixel it wouln't fit on the 1366x768 screen so part of the image wouldn't be displayed.

[bigshotceo]

I should probably clarify; I'm using the dualview function of my 6800gt in which whenever I play a video file it automatically plays in fullscreen on my secondary monitor (my lcd tv) as well. What I'm wondering is if it gets resized to fullscreen by my software, or does it simply get sent as its original size and cause the tv to rescale it to fullscreen resolution.

[jagabo]

I should probably clarify; I'm using the dualview function of my 6800gt in which whenever I play a video file it automatically plays in fullscreen on my secondary monitor (my lcd tv) as well. What I'm wondering is if it gets resized to fullscreen by my software, or does it simply get sent as its original size and cause the tv to rescale it to fullscreen resolution.

It gets resized to whatever the secondary ouput is set to.

[guns1inger]

Most LCD TVs have build in scaling for HDMI/DVI/Component inputs, but do not have scaling for VGA inputs. You still haven't said how you have connected your PC and TV.

[Amish Electrician]

This is exactly what I was wondering about. I have just hooked my computer to my new Sony bravia kdl-46vl130 VIA the DVI out to TV HDMI I only have an old ATI all in wonder 7500 so the most I get is 720p. If I watch standard DVDs on it would that not be up scaling as apposed to using my old progressive DVD play that comes up as 480p?
If I get a computer blue ray player in the future would it be useless. My TV says it will do 1080p but when I set my video card to that it says unsupported.

[jagabo]

This is exactly what I was wondering about. I have just hooked my computer to my new Sony bravia kdl-46vl130 VIA the DVI out to TV HDMI I only have an old ATI all in wonder 7500 so the most I get is 720p. If I watch standard DVDs on it would that not be up scaling as apposed to using my old progressive DVD play that comes up as 480p?

If you have the graphics card set to output 1280x720, then your 720x480 DVD is upscaled to 1280x720 (assuming full screen output) by the graphics card (or media player, depending on the setup), then the HDTV is scaling again to whatever its native resolution is.

Your DVD player outputs the 720x480 DVD as 720x480p and then the the HDTV upscales to its native resolution.

If I get a computer blue ray player in the future would it be useless.

With your graphics card set to 1280x720, the 1920x1080 Blu-ray source will be downscaled to 1280x720 by the graphics card (or player) then scaled again by the HDTV to whatever its native resolution is.

My TV says it will do 1080p but when I set my video card to that it says unsupported.

Make sure you have the refresh rate set to whatever your HDTV supports. Typically 1920x1080 60 Hz. This should be listed in the manual.

I don't know your particular TV but even though it has a 1920x1080 LCD panel (which is by definition progressive) doesn't necessarily mean that it accepts 1920x1080p as in input. It may only accept 1920x1080i which it then converts to progressive for display.

[Amish Electrician]

Weirdest thing happen I was messing with the settings trying to get 1080p the screen said unsupported but now I cant even get back to the old settings. No matter what I set it to it says unsupported WTF. So now I am back to the VGA connection set the 1280x720

[edDV]

Back to the original poster...

Here's my question: I have some 1080p mkv videos that I'd like to play back on my w4207 LCD tv. My video card is set is a 6800gt set at 1366 by 768 (the TV's recommended resolution). Will the video be converted to 768p by my media software (media player classic) and sent to the tv as 768p or will it be sent as 1080i? Also, if I play 1080i video, what resolution will it be sent to the tv as? Will the de-interlacing be done by my software or by the tv?

Scaling can happen in software, in the display card or in the HDTV processor.

If your display card is set to 1366x768 out and the HDTV has native 1366x768 resolution, then the TV just displays what it is given from the NVidia card.

Assuming "clone mode" your 1080p mkv file can be played in several ways. Lets assume, since you didn't say, that your PC LCD monitor is set to 1650x1050. You have the option to play your 1920x1080p file without scaling. In that case you would only see the center 1680x1050 pixels of the file on the computer LCD and only the center 1366x768 pixels on the HDTV.

If you select "Full Screen" in the player, the display card will scale the playback to fit 1680x1050 for the computer monitor and 1366x768 for the HDTV output.

Make sense?

[edDV]

As for Amish Electrician,

Your DVD is natve 720x480.

If your TV has native 1920x1080p but your display card is limited to 1280x720p then the computer outputs 1280x720p and the HDTV upscales that to 1920x1080p (or 5% larger if it overscans).

When you play your DVD without up scaling, it will show as either a 720x480 (native) window or 852x480 (scaled 16:9) or 640x480 (scaled 4:3) depending on player aspect ratio settings. These windows will show on the HDTV inside a 1280x720 backgound that the HDTV has upscaled to 1920x1080. If you select "full screen" in the player "view", the DVD will be expanded (upscaled) to fill the 1280x720 screen. Then the TV upscales that to 1920x1080.

[jagabo]

I set my card in clone mode but make the HDTV the primary display and the LCD monitor the secondary display. So I have a 1920x1080 60p desktop which is mapped pixel-for-pixel on the HDTV and the secondary monitor is a 1680x1050 window that follows the mouse cursor around the desktop.

[edDV]

"Clone mode" works differently on various cards. Some scale both displays, others default to the primary display and map that window size to the second display. If the second display is smaller, you only see a portion of the screen. If the second display has larger resolution, the desktop shows as a window.

"DualView" mode for NVidia allows independent settings for each display.

"Theater Mode" for ATI causes media to play full screen on the TV regardless of size settings on the computer monitor.

[Amish Electrician]

So does it matter if I hook it up to the VGA port or the HDMI because on the VGA port I can set it to 1920x1080 and it works fine but need a magnify glass to see the text :{

[edDV]

So does it matter if I hook it up to the VGA port or the HDMI because on the VGA port I can set it to 1920x1080 and it works fine but need a magnify glass to see the text :{

VGA "PC Port" usually displays input directly without overscan. The DVI/HDMI port usually overscans causing loss of the image edges. This isn't much of an issue for playing movies but can cause loss of Windows Taskbar menus.

Small print at 1920x1080 is to be expected but not an issue for playing TV captures or DVD. Those people scale text for TV viewing at several feet back.