Here’s a version that’s much simpler – not sure how performant it is. Heavily based on some django snippet I found while building RGBA -> JPG + BG support for sorl thumbnails. from PIL import Image png = Image.open(object.logo.path) png.load() # required for png.split() background = Image.new(“RGB”, png.size, (255, 255, 255)) background.paste(png, mask=png.split()[3]) # 3 … Read more
Old post, but for future reference: Inspired by this question and links found here, I’ve written a JPEGImageReader plugin for ImageIO that supports CMYK color models (both with original color model, or implicitly converted to RGB on read). The reader also does proper color conversion, using the ICC profile embedded in the JPEG stream, in … Read more
libjpeg-dev is required to be able to process jpegs with pillow (or PIL), so you need to install it and then recompile pillow. It also seems that libjpeg8-dev is needed on Ubuntu 14.04 If you’re still using PIL then you should really be using pillow these days though, so first pip uninstall PIL before following … Read more
A more succinct way is to get the ImageWriter directly from ImageIO: ImageWriter jpgWriter = ImageIO.getImageWritersByFormatName(“jpg”).next(); ImageWriteParam jpgWriteParam = jpgWriter.getDefaultWriteParam(); jpgWriteParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT); jpgWriteParam.setCompressionQuality(0.7f); ImageOutputStream outputStream = createOutputStream(); // For example implementations see below jpgWriter.setOutput(outputStream); IIOImage outputImage = new IIOImage(image, null, null); jpgWriter.write(null, outputImage, jpgWriteParam); jpgWriter.dispose(); The call to ImageWriteParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT) is needed in order to explicitly set … Read more
People say that ImageMagick is much faster. At best just compare both libraries and measure that. Prepare 1000 typical images. Write two scripts — one for GD, one for ImageMagick. Run both of them a few times. Compare results (total execution time, CPU and I/O usage, result image quality). Something which the best everyone else, … Read more
That’s funny you asked this, I just did this recently for my work’s site and I was thinking I should write a tutorial… Here is how to do it with PHP/Imagick, which uses ImageMagick: $usmap = ‘/path/to/blank/us-map.svg’; $im = new Imagick(); $svg = file_get_contents($usmap); /*loop to color each state as needed, something like*/ $idColorArray = … Read more
If you only want the orientation tag and nothing else and don’t like to include another huge javascript library I wrote a little code that extracts the orientation tag as fast as possible (It uses DataView and readAsArrayBuffer which are available in IE10+, but you can write your own data reader for older browsers): function … Read more
You should be aware of a few key factors… First, there are two types of compression: Lossless and Lossy. Lossless means that the image is made smaller, but at no detriment to the quality. Lossy means the image is made (even) smaller, but at a detriment to the quality. If you saved an image in … Read more