How to resample an image w/o changing the size.

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fmw42
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Re: How to resample an image

Post by fmw42 »

fswat wrote:I have several images that I want to resample to 75 dpi for viewing on a Monitor. What I don't understand is how to write out the 75 dpi in pixels for the convert -resample 300x300 input.jpg output.jpg command. Cansomeone help... thank you Frank

dpi has nothing to do with how it is viewed on a monitor. dpi has to do with printing size.

If all you want to do is change the dpi and not the image dimensions (WxH), then just use -density. If you want to change the image size and not the dpi, then use -resize or -scale.

If you want to do both either combine them or use -resample

see
http://www.imagemagick.org/script/comma ... hp#density
http://www.imagemagick.org/script/comma ... php#resize
http://www.imagemagick.org/script/comma ... p#resample
http://www.imagemagick.org/Usage/resize/#resample
http://www.imagemagick.org/Usage/resize/#resize
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