将（8 * 7 px）位图图像调整为800 x 700

Question

I created about 100 png files that are all 8*7 pixels in size, they contain tiny faces.

I wanted to display one of the faces in a WPF Image , to do so, I created a Bitmapimage (using the Stretch.Fill option) and put the png into it's urisource, then I used the bitmapimage as the images source.

As you can imagine, it looks kinda weird, all I wanted to do was to get a bigger picture, not to change any pixels (like when you use windows image viewer and zoom into it, there's no quality loss and the pixels don't change, meaning that you don't loose the shapes and colors of the image)

I'm sure there's a way to just "zoom" into my 8*7px picture, or to copy those pixels and draw them again, but bigger.

I'm really sorry for my bad english, I still hope you understand me and are able to help.

Thank you very much in advance, there's really nothing more to say.

Answer 1

I imagine the resulting image looks rather blurry. The reason isn't "loss" of quality - instead, it's extrapolating the detail that simply isn't in the original image. And for photos and similar images, it's usually a better idea to use some smooth interpolation, so that's what WPF does.

I'm not sure if there's a better way in WPF (it might), but you can manually create a new bitmap without the smooth interpolation like this:

var src = new Bitmap("D:\\Untitled.png");
var dst = new Bitmap(800, 700);

using (var gr = Graphics.FromImage(dst))
{
  gr.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;
  gr.DrawImage(src, new Rectangle(0, 0, 800, 700));
}

dst.Dump();

The dst variable will have the resized bitmap with "nearest neighbour" interpolation - the "pixelated" look.

EDIT:

The WPF-native way would be to use RenderOptions.BitmapScalingMode="NearestNeighbor" . If you're creating the images dynamically, this corresponds to RenderOptions.SetBitmapScalingMode(bmp, BitmapScalingMode.NearestNeighbor) of course.