May 11, 2021 PHP
PHP provides a wealth of image processing functions, including:
| Function | Describe |
|---|---|
| gd_info() | Get information about the currently installed GD library |
| getimagesize() | Get image information |
| imagesx() 、imagesy() | Gets the width and height of the image |
| getimagesizefromstring() | Get image information |
| image_type_to_extension() | Get the picture suffix |
| image2wbmp() | Output WBMP pictures |
| imageaffinematrixconcat() | Connect the two matrices |
| imageaffinematrixget() | Gets the matrix |
| image_type_to_mime_type() | Returns the MIME type of the image |
| imageaffine() | Returns an image that has been a2formed |
| imagealphablending() | Sets the process mode of the image |
| imagecolorallocate() | Assign color to an image |
| imagecolorallocatealpha() | Assign color and transparency to an image |
| imagecolorat() | Get the color index value for a pixel |
| imagecolorclosest() | Get the index value of the color closest to the specified color |
| imagecolorclosestalpha() | Get an index of the colors closest to the specified color transparency |
| imagecolorclosesthwb() | Get a black-and-white index of the color closest to the specified color |
| imageantialias() | Whether anti-aliasing is used |
| imagearc() | Draw an elliptical arc |
| imagechar() | Write out landscape characters |
| imagecharup() | Draw a character vertically |
Using the PHP image processing function, you need to load the GD support library. Make sure the php .ini the GD library is loaded:
On the Window server:
extension = php_gd2.dll
On 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()); ?>
The output is roughly 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)
}