Converting images to a specific JPEG quality

I want to convert image formats to JPG in a specific quality The following command doesn't work for some reason , all i get is NULL gm convert -quality 80 '/tmp/phpK31vNK' JPEG:'/tmp/phpK31vNK' && cat '/tmp/phpK31vNK' However the following command

Return the image without saving on the server (node.js)

I create an image in GraphicsMagick on Node.js and I want to give it back without saving on server. How may I do this? I have this code: var fs = require('fs'); var gm = require('gm'); var captchaImg = gm.(650, 200, "#ddff99f3"); for(var i = 0;

PSD to PNG conversion does not match

When converting a PSD file with a transparent background using GraphicsMagick, my PNG image is more "dull/lighter" than the source image. I've used the following gm mogrify -level (with countless options) gm mogrify -modulate (with countless opt

Determine if an image is from & ldquo; blank & rdquo; paper

We are making a tool that will allow a chain of photos to be taken. Mixed in with real photos will be photos of blank sheets of paper. I want to separate the series of photos by identifying the images of blank pages. I'm trying to find a way to ident

Fixed Height Batch (CLI)

I have images of variable height and width, and I want to crop them all to be 200 pixels high, without any resizing. i.e. their width will remain the same, and height will be 200px. I want to use "north" gravity for this. Any CLI tool that allow

Cloud / RESTful Interface for Image / GraphicsMagick

I'm looking for a cloud service to where I can upload images and get them cropped / resized. Basically I'm looking for zencoder, but for images instead of video. I know about cloudinary but it forces you to store the images on their system so that th

Creating multiple thumbnails in ImageMagick / GraphicsMagick

I'm currently writing a shellscript for Bash, that will create different size thumbnails for some rather massive amounts of large images. I was wondering if it's possible to get GM/IM to create multiple sizes of thumbs in one run, to avoid loading th

Reducing colors in a PNG image makes the file size larger

I am using ImageMagick to programmatically reduce the size of a PNG image by reducing the colors in the image. I get the images unique-colors and divide this by 2. Then I assign this value to the -colors option as follows: variable = unique-colors /