Image Quality in Imagemagick

[Ganesha]

I use a jar http://www.java2s.com/Code/Jar/j/Downlo ... 085jar.htm for resizing images like jpeg,png. This jar gives a good quality of image after resize which I feel better than that of imagemagick's command

Code: Select all

convert test.jpg -resize WxH> testresize.jpg

Is there any other way of resizing image to produce the same quality of the jar using convert command?

[GeeMack]

Code: Select all

convert test.jpg -resize WxH> testresize.jpg

Is there any other way of resizing image to produce the same quality of the jar using convert command?

Maybe try this...

Code: Select all

convert test.jpg -resize WxH> -quality 100 testresize.jpg

[Ganesha]

On doing so, what filter it uses?

[Bonzo]

I think the standard filter is Lanczos; see: http://www.imagemagick.org/script/comma ... php#filter

[snibgo]

I wouldn't use JPEG as output to compare resizing from two different systems.

Perhaps you can show us an example input and output where you think the java version is better.

[fmw42]

Lots of different resizing techniques depending upon upscale vs downscale and subject matter. See
http://www.imagemagick.org/Usage/filter/
http://www.imagemagick.org/Usage/filter/nicolas/

[mikmach]

By default IM jpeg -quality is somewhere between 75 and 85. Try passing 90 or 95 (100 is overkill in most cases). Also to improve look of files with sharp edges don't forget about '-sampling-factor 1x1'.

[fmw42]

IM jpeg default quality is to match the input if the input quality is given or if not use 92. See http://www.imagemagick.org/script/comma ... hp#quality