hi guys I tried googling and searching these forums but to no avail I cannot find out what specifically 1:1 pixel mapping is.

As a guess would it be that it matches the source amount of pixels without stretching or resizing the input to use the full amount of pixels, and rather just use ONLY the amount of pixels from the source?

Example:

I have a 1920 X 1080 TV.
I put in a game that has a Resolution of 1280 X 720.

If my TV has 1:1 turned on it will only use 1280 lines of the TV going horizontally, and 720 lines of resolution vertically, without stretching or changing the image as if it is a native resolution with black bars?

Thanks

When people talk about 1:1 pixel mapping, they are mostly interested in being able to feed the display its native resolution and not have the picture stretched in any way. This is particularly important when using a display with a computer where there are often important details that are only 1 pixel wide.

In your example, you'd want to be able to send it 1920x1080 and have it exactly fill the screen. You may find that it will scale 1920x1080 to, for example, 2016x1134, then display it centered on your 1920x1080 screen with the edges cut off. Scaling like this always results in reduced picture quality, but it often done to hide the extreme edges of the picture which may not be pretty. It simulates overscan on a CRT TV.

1:1 pixel mapping is supposed to take the incoming pixel count and match it up exactly with an area with that many pixels on the screen. If 1280x720 source was put on a 1920x1080 screen using 1:1 pixel mapping, then 720 rows of pixels should be utilized and within each of those rows 1280 pixels should be utilized.

Most TV's do not have specific adjustments for 1:1 pixel mapping. Instead you adjust the height (VSIZE) until the number of scan lines just matches with no skips and no duplicates and then adjust the width (HSIZE) until the pixels spill over onto each row just right without straddle blurring.

In theory 1:1 pixel mapping should give you a much sharper image although it will not fill the entire screen unless it matches the exact resolution of your screen. For instance, if you had a 1365x768 resolution display (most non-1080 displays), a 1280x720 image would have black bars on all sides, but it would not have to do any scaling. Once you scale any image either up or down, you essentially lose half your resolution, because you have to blend some pixel information across pixel boundaries and therefore you can't preserve the exact sharpness of your original resolution. Different scalars will do a better or worse job of it, and the good scalars have gotten really, really good, so the difference you notice is much smaller, but a 1920x1080 image on a 1920x1080 display will not have any attempted image processing with 1:1 pixel mapping and just pass the image straight through so the pixels that were sent to the display are the pixels that show up with none added or removed, also with no overscan.

thanks for all the info :).

In theory 1:1 pixel mapping should give you a much sharper image although it will not fill the entire screen unless it matches the exact resolution of your screen. For instance, if you had a 1365x768 resolution display (most non-1080 displays), a 1280x720 image would have black bars on all sides, but it would not have to do any scaling. Once you scale any image either up or down, you essentially lose half your resolution, because you have to blend some pixel information across pixel boundaries and therefore you can't preserve the exact sharpness of your original resolution. Different scalars will do a better or worse job of it, and the good scalars have gotten really, really good, so the difference you notice is much smaller, but a 1920x1080 image on a 1920x1080 display will not have any attempted image processing with 1:1 pixel mapping and just pass the image straight through so the pixels that were sent to the display are the pixels that show up with none added or removed, also with no overscan.


Put this quote in a FAQ!! Hehe, nice job at explaining

In theory 1:1 pixel mapping should give you a much sharper image although it will not fill the entire screen unless it matches the exact resolution of your screen. For instance, if you had a 1365x768 resolution display (most non-1080 displays), a 1280x720 image would have black bars on all sides, but it would not have to do any scaling.

Well, that's one way to look at it, but not what most people mean when they are 1x1 mapping.

Basically all digital fixed-pixel displays must scale(up or down) any incoming video to the display resolution when it differs from the display's native resolution, whatever that resolution may be. Unfortunately, many displays have lackluster scaling capabilities. Using an external scaler/video processor may allows you to do better quality scaling for a better image, but that may be impeded if the display is going to scale again on top of that. By using an external scaling device that feeds EXACTLY the native resolution of the display, the display's scaling should be bypassed entirely, allowing you to take full advantage of higher quality scaling capabilities from external scalers/processors if you wish.


Once you scale any image either up or down, you essentially lose half your resolution, because you have to blend some pixel information across pixel boundaries and therefore you can't preserve the exact sharpness of your original resolution.

That is not true at all. The ideal way to reconstruct any image is to upscale it to a display with a significantly higher resolution(theoretically infinite) than the source's native sampling rate. The suggestion that you "lose half your resolution" is nonsense.

Put this quote in a FAQ!! Hehe, nice job at explaining


It may be well articulated, but that doesn't make it correct.