This ability is essential for my application which uploads any of GIF, JPEG or PNG and simultaneously creates a thumbnail of identical image type and identical filename (full size and thumbnail versions being stored in different folders).Īfter uploading and moving the image in the usual way, a switch($image_type) statement ensures that the optimum code is used to generate the thumbnail regardless of image type. If there some errors, I hope you could understood the idea.Īfter much devious mindbending, I have found a way to test any GIF for presence of background transparency. I used (nearly) the following code to make resized GIF images trnsparent only when the transparency is needed: The solution is not to use some default transparent color and to leave the resized image without transparent color (the same as original GIF). The problem is, that the color you force to be transparent can be used in the original GIF as opaque and you will loose that color in resized image. But sometimes the transparent color in GIF images can be not set.
A good example of forced transparency in resized GIF image was given by markglibres at yahoo dot com 2 02:48.
Pay attention, that some GIF images may not include a transparent color. Imagecolortransparent ( $new_image, $transparencyIndex ) Imagefill ( $new_image, 0, 0, $transparencyIndex ) $transparencyIndex = imagecolorallocate ( $new_image, $transparenc圜olor, $transparenc圜olor, $transparenc圜olor ) $transparenc圜olor = imagecolorsforindex ( $image_source, $transparencyIndex ) $image_source = image resource identifier returned by imagecreatefromjpeg, imagecreatefromgif and imagecreatefrompng. $new_image = image resource identifier such as returned by imagecreatetruecolor(). NOTE: Transparency is only supported on GIF and PNG files. I've made a very simple script that will retain transparency of images especially when resizing.
#Black transparent rectangle archive#
Getting Started Introduction A simple tutorial Language Reference Basic syntax Types Variables Constants Expressions Operators Control Structures Functions Classes and Objects Namespaces Enumerations Errors Exceptions Fibers Generators Attributes References Explained Predefined Variables Predefined Exceptions Predefined Interfaces and Classes Predefined Attributes Context options and parameters Supported Protocols and Wrappers Security Introduction General considerations Installed as CGI binary Installed as an Apache module Session Security Filesystem Security Database Security Error Reporting User Submitted Data Hiding PHP Keeping Current Features HTTP authentication with PHP Cookies Sessions Dealing with XForms Handling file uploads Using remote files Connection handling Persistent Database Connections Command line usage Garbage Collection DTrace Dynamic Tracing Function Reference Affecting PHP's Behaviour Audio Formats Manipulation Authentication Services Command Line Specific Extensions Compression and Archive Extensions Cryptography Extensions Database Extensions Date and Time Related Extensions File System Related Extensions Human Language and Character Encoding Support Image Processing and Generation Mail Related Extensions Mathematical Extensions Non-Text MIME Output Process Control Extensions Other Basic Extensions Other Services Search Engine Extensions Server Specific Extensions Session Extensions Text Processing Variable and Type Related Extensions Web Services Windows Only Extensions XML Manipulation GUI Extensions Keyboard Shortcuts ? This help j Next menu item k Previous menu item g p Previous man page g n Next man page G Scroll to bottom g g Scroll to top g h Goto homepage g s Goto search
0 kommentar(er)
