PHP Image Processing
PHP provides rich image processing functions, including:
function | description |
---|---|
gd_info () | Access to information currently installed GD library |
getimagesize () | Get image information |
getimagesizefromstring () | Get image information |
image_type_to_extension () | Get Picture suffix |
image_type_to_mime_type () | Returns the MIME type of image |
image2wbmp () | Output WBMP image |
imageaffine () | Back after the image after affine transformation |
imageaffinematrixconcat () | Connecting the two matrices |
imageaffinematrixget () | Get Matrix |
imagealphablending () | Setting the image blending mode |
imageantialias () | Whether to use anti-aliasing (antialias) function |
imagearc () | Videos elliptical arcs |
imagechar () | Write transverse character |
imagecharup () | Draw a character vertically |
imagecolorallocate () | Assign a color to an image |
imagecolorallocatealpha () | Assign a color and transparency of an image |
imagecolorat () | Get color value of a pixel index |
imagecolorclosest () | Get the index of the color closest to the specified color |
imagecolorclosestalpha () | Index specified color + alpha acquires closest color |
imagecolorclosesthwb () | Black and white made with the specified color index closest chromaticity |
imagesx (), imagesy () | Get image width and height |
GD library
Use PHP image processing functions, you need to load GD library support. Make sure php.ini loaded GD library:
Window server:
extension = php_gd2.dll
Linux and Mac systems:
extension = php_gd2.so
Use gd_info () function to view information about the currently installed GD library:
<?php var_dump(gd_info()); ?>
Output is as follows:
array(12) { ["GD Version"]=> string(26) "bundled (2.1.0 compatible)" ["FreeType Support"]=> bool(true) ["FreeType Linkage"]=> string(13) "with freetype" ["T1Lib Support"]=> bool(false) ["GIF Read Support"]=> bool(true) ["GIF Create Support"]=> bool(true) ["JPEG Support"]=> bool(true) ["PNG Support"]=> bool(true) ["WBMP Support"]=> bool(true) ["XPM Support"]=> bool(false) ["XBM Support"]=> bool(true) ["JIS-mapped Japanese Font Support"]=> bool(false) }