: Scale down an image in GIMP without losing resolution How do I scale down an image to a smaller size in GIMP without an unnecessary loss of resolution? I know that I am losing too much image

@Sent7350415

An answer using only raster image processing

Technically you lose resolution when you downscale, since you are displaying the same image with less pixels. The question is therefore to avoid more resolution loss than strictly necessary. The extra resolution loss is usually due to spatial frequency folding, so these high frequencies must be removed before scaling down. And suppressing high spatial frequencies is just blurring the image. So:


Filter>Blur>Gaussian blur
Use a blur radius equal to your scaling factor (1024->240, blur radius=4.3, note that Gimp will let you enter the radius as 1024/240 and do the computation for you).
Once the blur is applied, Image>Scale image





You can restore a bit of visual pop using a sharpening filter (here: Filters>Enhance>Unsharp mask with radius=1 and amount=1)

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@Gloria351

This answer was suggested by Paolo Gibellini in two comments. It's also possible to downscale an image without losing too much resolution in GIMP using a similar method, however I prefer to use Inkscape because it's a lot easier to do it with Inkscape.


The original image can be a file format like .png, .svg, .jpg, etc., preferably .png or .svg because Inkscape will save .jpg images as .png files.
Open the original image file in Inkscape. When you open the file, Inkscape will open a small window asking you to select either link or embed image. Click the radio button to select embed.
Select File -> Export Bitmap. This will open a little Export Bitmap window.
Under the Export area heading in the Export Bitmap window click the Page button.
Under the Bitmap size heading in the Export Bitmap window select new values for Width and Height to downscale the image.
Click the Browse button and browse to the folder in which the file will be saved.
Type a name for the exported file with a .png extension to save it as a .png file or with an .svg extension to save it as a .svg file, etc.
Click the Save button.
Click the Export button.

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@Tiffany317

Scaling bitmaps is never without loss. Both upscaling, and downscaling will produce interpolation artifacts. This can be done much better with vector graphics. So if we can trace the bitmap we will get better results.

Scaling artifacts become even more obvious when done on an indexed image. We can not calculate interpolated colors on downscaling an indexed image.

To still be able to scale an indexed image we should therefore change the image mode to RGB before we scale it. Details on downscaling will then be much better preserved:



If we need an indexed image mode we can change it back after scaling.

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