How to view large images

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Viewing large images can be quite tricky. Maps and other outputs of OpenStreetMap tools can sometimes be in the form of really large images. You could try to look at the whole picture and pan and zoom in the various picture viewers, but this can require a lot of memory and may be quite slow.

Slice up the image

One workaround is to slice the picture into pieces and start a slide show and lean back.

Here is one way to do this:

  • create an empty folder
  • copy big file here
  • use imagemagick's convert to convert to jpg format
  • use imagemagick's convert -crop to slice the picture
  • now select the first picture and start the slide show

Code

Installation for Ubuntu

sudo apt-get install imagemagick

Convert image format

convert file.png file.jpg

Slice image

convert file.jpg -crop '1024x768' out.jpg