批量转换ImageMagick的Shell脚本

Question

I want to batch convert / loop through all images within the folder "/input" and then optimise all the images and finally output them in the folder "/output".

How can I do something similar to this:

convert /Users/james/Desktop/image-magick/santorini.jpg -sampling-factor 4:2:0 -strip -quality 75 -resize 700x466! -interlace JPEG -colorspace RGB -background white -flatten /Users/james/Desktop/image-magick/final/santorini-opt.jpg 

^ Currently with the above script, I have to run manually for every image, one at a time!

How can I do something similar using shell script to do it all for me in bulk?

Answer 1

You should use mogrify command instead of convert . Use -path option to create output images in a specific directory. If you don't, your original images will be overwritten.

mogrify -sampling-factor 4:2:0 -strip -quality 75 -resize 700x466! -interlace JPEG -colorspace RGB -background white -flatten -path /Users/james/Desktop/image-magick/final/ /Users/james/Desktop/image-magick/*.jpg

Answer 2

The previous answer is almost correct. Also use -strip first before any other settings or they will be lost. Also current versions of ImageMagick use -colorspace sRGB unless you want the darker linear RGB colorspace. The following has proper ImageMagick syntax to strip, convert to sRGB, resize and then set all the jpg output settings.

cd path2/inputdirectory
mogrify -strip -colorspace sRGB -resize "700x466!" -background white -flatten -interlace JPEG -sampling-factor 4:2:0 -quality 75 -path /Users/james/Desktop/image-magick/final/ *.jpg

Note that JPG does not support transparency, so I am not sure why you have -background white -flatten in the command. That would be appropriate if your input were png (ie *.png or just * to handle all formats)