Using the php gd library:
imagefilter($im, IMG_FILTER_GRAYSCALE);
imagefilter($im, IMG_FILTER_CONTRAST, -100);
Check the user comments in the link above for more examples.
More Related Contents:
- How to provide dynamic HTML in PHP?
- inserting image in database using php [closed]
- Output an Image in PHP
- Efficient JPEG Image Resizing in PHP
- Creating a thumbnail from an uploaded image
- Multiple Image Upload PHP form with one input
- PHP: How to check if image file exists?
- Add ‘Watermark’ to images with php [closed]
- Calculating image size ratio for resizing
- best way to determine if a URL is an image in PHP
- How to add text to an image with PHP GD library
- RGB to HSV in PHP
- Automatic image format detection in PHP
- How to merge transparent PNG with image using PHP?
- Resize images in PHP without using third-party libraries?
- Get image color
- php GD create a transparent png image
- Php : Convert a blob into an image file
- Convert JPG/GIF image to PNG in PHP?
- Saving images in database mysql
- How to convert all images to JPG format in PHP?
- Crop whitespace from image in PHP
- Cropping image in PHP
- PHP upload image
- TCPDF error :Unable to get the size of the image
- the dreaded “Warning: imagecreatefromjpeg() : ‘/tmp/filename’ is not a valid JPEG file in /phpfile.php on line xxx”
- PHP – Create simple animated GIF from two JPEG images? [closed]
- Merge two PNG images with PHP GD library
- Merge two images in php
- How to stop PHP iMagick auto-rotating images based on EXIF ‘orientation’ data