I dont understand the explanation about why GIF files always has image resolution 72ppi.

I have tried using ImageMagick converting PNG to GIF specifying -density to be 300ppi, but the resulting GIF is still 72ppi.

CodePudding user response：

The GIF format does not store any value for "ppi" or "dpi" or pixel density/resolution - see Wikipedia.

I think software assumes 72 dpi, and then loads your image, updating that assumption if it finds anything better... which it never will in the case of GIF.

In any case, the dpi/ppi is irrelevant until such time as you want to print your image, and I don't know of anyone ever using GIF as a method of submission of images to any reputable printers or publications - TIFF is probably the preferred or most common method.