ZDoom

As the title says, i want to know how to resize an image without looking blurry or pixelated, is there any program? i already used photoshop, paint.net, gimp, and also a program called SmillaEnlarger

There's no detail "between" the pixels, so any upscaling is going to introduce artifacts. If you're okay with how they look, algorithms such as Scalex, xBRZ, and HQx can give a smoothed or semi-painterly look to the upscaling. GZDoom incorporates these natively in the High-Quality resize option, so you can play with that to see how they look.

Caligari87 wrote:There's no detail "between" the pixels, so any upscaling is going to introduce artifacts. If you're okay with how they look, algorithms such as Scalex, xBRZ, and HQx can give a smoothed or semi-painterly look to the upscaling. GZDoom incorporates these natively in the High-Quality resize option, so you can play with that to see how they look.

In this case i need to reduce the size of the image...it is the same thing?

Well that depends. You can't shrink the image pixel size without losing data (and hence, quality).

If you want something high-res to render at a smaller scale, you can using GZDoom's features (like the Scale property in TEXTURES or DECORATE).

What kind of picture is it? Some filters should be better than others at prioritizing certain details over others, while if this is a smaller piece of pixel art it might be faster to manually edit and smooth out a pixelated resize than to find the exact algorithm that gets you what you need.

Caligari87 wrote:Well that depends. You can't shrink the image pixel size without losing data (and hence, quality).

If you want something high-res to render at a smaller scale, you can using GZDoom's features (like the Scale property in TEXTURES or DECORATE).

You can do that with only with textures?

as long as you maintain the aspect ratio of the image and dont decide to reduce 50% of the original resolution you shouldn't have any kind of problem with gimp\photoshop