Similar interpolations are visible on the left and right sides of the 'Y', and elsewhere on the screen. The average of two dark pixels is also dark, so it is the same colour as the rest of the 'A'. On the right side of the 'A', another column of interpolated pixels has ended up in between the two columns of dark pixels. These pixels have been averaged out as a medium gray. On the left side of the 'A', a column of pixels has been interpolated between the dark pixels of the 'A' and the light pixels of the background.

Here are some detailed photos of the 'AY' from the '1Player' text:

If you look closely at the Advance's display with an un-stretched Game Boy game, then a stretched one, it's possible to identify which columns have had their values calculated by this 'averaging' interpolation. In this instance, rather than choosing to duplicate one column to fill the empty pixels, you take an average of the values in the columns to the left and the right of each empty pixel, and use this calculated value instead. It's a simple method, but doesn't look that good, because some columns won't be doubled at all, but others will.Īn alternative approach is to use a technique called interpolation. Every two columns of pixels from an old Game Boy game will now need to be 'stretched' over three columns of the Advance's screen.īut what values should be assigned to the pixels in these extra third columns? You could double up some of the original columns' pixels, doubling the 'width' of all the odd columns, or perhaps the even ones. Instead, Nintendo selected a screen for the Advance that had a resolution that is one and a half times (or 3/2) that of the original Game Boy (160 x 3/2 = 240). It's not always feasible to double the resolution of your screen it's likely that such a resolution wasn't available (or affordable) in a handheld size at the time of the Advance. It would effectively mean that each of the Game Boy's pixels were twice as wide as before.

If the Advance had twice the horizontal resolution of the Game Boy, it would be easy to stretch: each column of pixels could be repeated twice. Horizontally, the image is definitely stretched. Firstly, the stretching isn't done in the vertical direction: Game Boy (and Color) games only used 144 rows of the 160 available on Advance screen, so there'd be black 'letterbox' bars at the top and bottom, whether you stretched the image widescreen (with the shoulder buttons) or not.

Gameboy sp with brighter screen