silverstripe-framework/filesystem/GD.php
2012-11-27 11:20:19 +01:00

475 lines
13 KiB
PHP

<?php
/**
* A wrapper class for GD-based images, with lots of manipulation functions.
* @package framework
* @subpackage filesystem
*/
class GDBackend extends Object implements Image_Backend {
protected $gd, $width, $height;
protected $quality;
protected static $default_quality = 75;
/**
* Set the default image quality.
* @param quality int A number from 0 to 100, 100 being the best quality.
*/
public static function set_default_quality($quality) {
if(is_numeric($quality) && (int) $quality >= 0 && (int) $quality <= 100) {
self::$default_quality = (int) $quality;
}
}
public function __construct($filename = null) {
// If we're working with image resampling, things could take a while. Bump up the time-limit
increase_time_limit_to(300);
if($filename) {
// We use getimagesize instead of extension checking, because sometimes extensions are wrong.
list($width, $height, $type, $attr) = getimagesize($filename);
switch($type) {
case 1:
if(function_exists('imagecreatefromgif'))
$this->setImageResource(imagecreatefromgif($filename));
break;
case 2:
if(function_exists('imagecreatefromjpeg'))
$this->setImageResource(imagecreatefromjpeg($filename));
break;
case 3:
if(function_exists('imagecreatefrompng')) {
$img = imagecreatefrompng($filename);
imagesavealpha($img, true); // save alphablending setting (important)
$this->setImageResource($img);
}
break;
}
}
$this->quality = self::$default_quality;
parent::__construct();
}
public function setImageResource($resource) {
$this->gd = $resource;
$this->width = imagesx($resource);
$this->height = imagesy($resource);
}
public function setGD($gd) {
Deprecation::notice('3.1', 'Use GD::setImageResource instead',
Deprecation::SCOPE_CLASS);
return $this->setImageResource($gd);
}
public function getImageResource() {
return $this->gd;
}
public function getGD() {
Deprecation::notice('3.1', 'GD::getImageResource instead',
Deprecation::SCOPE_CLASS);
return $this->getImageResource();
}
/**
* Set the image quality, used when saving JPEGs.
*/
public function setQuality($quality) {
$this->quality = $quality;
}
/**
* Resize an image to cover the given width/height completely, and crop off any overhanging edges.
*/
public function croppedResize($width, $height) {
if(!$this->gd) return;
$width = round($width);
$height = round($height);
// Check that a resize is actually necessary.
if ($width == $this->width && $height == $this->height) {
return $this;
}
$newGD = imagecreatetruecolor($width, $height);
// Preserves transparency between images
imagealphablending($newGD, false);
imagesavealpha($newGD, true);
$destAR = $width / $height;
if ($this->width > 0 && $this->height > 0 ){
// We can't divide by zero theres something wrong.
$srcAR = $this->width / $this->height;
// Destination narrower than the source
if($destAR < $srcAR) {
$srcY = 0;
$srcHeight = $this->height;
$srcWidth = round( $this->height * $destAR );
$srcX = round( ($this->width - $srcWidth) / 2 );
// Destination shorter than the source
} else {
$srcX = 0;
$srcWidth = $this->width;
$srcHeight = round( $this->width / $destAR );
$srcY = round( ($this->height - $srcHeight) / 2 );
}
imagecopyresampled($newGD, $this->gd, 0,0, $srcX, $srcY, $width, $height, $srcWidth, $srcHeight);
}
$output = clone $this;
$output->setImageResource($newGD);
return $output;
}
/**
* Resizes the image to fit within the given region.
* Behaves similarly to paddedResize but without the padding.
* @todo This method isn't very efficent
*/
public function fittedResize($width, $height) {
$gd = $this->resizeByHeight($height);
if($gd->width > $width) $gd = $gd->resizeByWidth($width);
return $gd;
}
/**
* hasImageResource
*
* @return boolean
*/
public function hasImageResource() {
return $this->gd ? true : false;
}
public function hasGD() {
Deprecation::notice('3.1', 'GD::hasImageResource instead',
Deprecation::SCOPE_CLASS);
return $this->hasImageResource();
}
/**
* Resize an image, skewing it as necessary.
*/
public function resize($width, $height) {
if(!$this->gd) return;
$width = round($width);
$height = round($height);
// Check that a resize is actually necessary.
if ($width == $this->width && $height == $this->height) {
return $this;
}
if(!$width && !$height) user_error("No dimensions given", E_USER_ERROR);
if(!$width) user_error("Width not given", E_USER_ERROR);
if(!$height) user_error("Height not given", E_USER_ERROR);
$newGD = imagecreatetruecolor($width, $height);
// Preserves transparency between images
imagealphablending($newGD, false);
imagesavealpha($newGD, true);
imagecopyresampled($newGD, $this->gd, 0,0, 0, 0, $width, $height, $this->width, $this->height);
$output = clone $this;
$output->setImageResource($newGD);
return $output;
}
/**
* Rotates image by given angle.
*
* @param angle
*
* @return GD
*/
public function rotate($angle) {
if(!$this->gd) return;
if(function_exists("imagerotate")) {
$newGD = imagerotate($this->gd, $angle,0);
} else {
//imagerotate is not included in PHP included in Ubuntu
$newGD = $this->rotatePixelByPixel($angle);
}
$output = clone $this;
$output->setImageResource($newGD);
return $output;
}
/**
* Rotates image by given angle. It's slow because makes it pixel by pixel rather than
* using built-in function. Used when imagerotate function is not available(i.e. Ubuntu)
*
* @param angle
*
* @return GD
*/
public function rotatePixelByPixel($angle) {
$sourceWidth = imagesx($this->gd);
$sourceHeight = imagesy($this->gd);
if ($angle == 180) {
$destWidth = $sourceWidth;
$destHeight = $sourceHeight;
} else {
$destWidth = $sourceHeight;
$destHeight = $sourceWidth;
}
$rotate=imagecreatetruecolor($destWidth,$destHeight);
imagealphablending($rotate, false);
for ($x = 0; $x < ($sourceWidth); $x++) {
for ($y = 0; $y < ($sourceHeight); $y++) {
$color = imagecolorat($this->gd, $x, $y);
switch ($angle) {
case 90:
imagesetpixel($rotate, $y, $destHeight - $x - 1, $color);
break;
case 180:
imagesetpixel($rotate, $destWidth - $x - 1, $destHeight - $y - 1, $color);
break;
case 270:
imagesetpixel($rotate, $destWidth - $y - 1, $x, $color);
break;
default: $rotate = $this->gd;
};
}
}
return $rotate;
}
/**
* Crop's part of image.
*
* @param top y position of left upper corner of crop rectangle
* @param left x position of left upper corner of crop rectangle
* @param width rectangle width
* @param height rectangle height
*
* @return GD
*/
public function crop($top, $left, $width, $height) {
$newGD = imagecreatetruecolor($width, $height);
imagecopyresampled($newGD, $this->gd, 0, 0, $left, $top, $width, $height, $width, $height);
$output = clone $this;
$output->setImageResource($newGD);
return $output;
}
/**
* Method return width of image.
*
* @return integer width.
*/
public function getWidth() {
return $this->width;
}
/**
* Method return height of image.
*
* @return integer height
*/
public function getHeight() {
return $this->height;
}
/**
* Resize an image by width. Preserves aspect ratio.
*/
public function resizeByWidth( $width ) {
$heightScale = $width / $this->width;
return $this->resize( $width, $heightScale * $this->height );
}
/**
* Resize an image by height. Preserves aspect ratio
*/
public function resizeByHeight( $height ) {
$scale = $height / $this->height;
return $this->resize( $scale * $this->width, $height );
}
/**
* Resize the image by preserving aspect ratio. By default, it will keep the image inside the maxWidth
* and maxHeight. Passing useAsMinimum will make the smaller dimension equal to the maximum corresponding dimension
*/
public function resizeRatio( $maxWidth, $maxHeight, $useAsMinimum = false ) {
$widthRatio = $maxWidth / $this->width;
$heightRatio = $maxHeight / $this->height;
if( $widthRatio < $heightRatio )
return $useAsMinimum ? $this->resizeByHeight( $maxHeight ) : $this->resizeByWidth( $maxWidth );
else
return $useAsMinimum ? $this->resizeByWidth( $maxWidth ) : $this->resizeByHeight( $maxHeight );
}
public static function color_web2gd($image, $webColor) {
if(substr($webColor,0,1) == "#") $webColor = substr($webColor,1);
$r = hexdec(substr($webColor,0,2));
$g = hexdec(substr($webColor,2,2));
$b = hexdec(substr($webColor,4,2));
return imagecolorallocate($image, $r, $g, $b);
}
/**
* Resize to fit fully within the given box, without resizing. Extra space left around
* the image will be padded with the background color.
* @param width
* @param height
* @param backgroundColour
*/
public function paddedResize($width, $height, $backgroundColor = "FFFFFF") {
if(!$this->gd) return;
$width = round($width);
$height = round($height);
// Check that a resize is actually necessary.
if ($width == $this->width && $height == $this->height) {
return $this;
}
$newGD = imagecreatetruecolor($width, $height);
// Preserves transparency between images
imagealphablending($newGD, false);
imagesavealpha($newGD, true);
$bg = GD::color_web2gd($newGD, $backgroundColor);
imagefilledrectangle($newGD, 0, 0, $width, $height, $bg);
$destAR = $width / $height;
if ($this->width > 0 && $this->height > 0) {
// We can't divide by zero theres something wrong.
$srcAR = $this->width / $this->height;
// Destination narrower than the source
if($destAR > $srcAR) {
$destY = 0;
$destHeight = $height;
$destWidth = round( $height * $srcAR );
$destX = round( ($width - $destWidth) / 2 );
// Destination shorter than the source
} else {
$destX = 0;
$destWidth = $width;
$destHeight = round( $width / $srcAR );
$destY = round( ($height - $destHeight) / 2 );
}
imagecopyresampled($newGD, $this->gd,
$destX, $destY, 0, 0,
$destWidth, $destHeight, $this->width, $this->height);
}
$output = clone $this;
$output->setImageResource($newGD);
return $output;
}
/**
* Make the image greyscale
* $rv = red value, defaults to 38
* $gv = green value, defaults to 36
* $bv = blue value, defaults to 26
* Based (more or less entirely, with changes for readability) on code from
* http://www.teckis.com/scriptix/thumbnails/teck.html
*/
public function greyscale($rv=38, $gv=36, $bv=26) {
$width = $this->width;
$height = $this->height;
$newGD = imagecreatetruecolor($this->width, $this->height);
$rt = $rv + $bv + $gv;
$rr = ($rv == 0) ? 0 : 1/($rt/$rv);
$br = ($bv == 0) ? 0 : 1/($rt/$bv);
$gr = ($gv == 0) ? 0 : 1/($rt/$gv);
for($dy = 0; $dy < $height; $dy++) {
for($dx = 0; $dx < $width; $dx++) {
$pxrgb = imagecolorat($this->gd, $dx, $dy);
$heightgb = ImageColorsforIndex($this->gd, $pxrgb);
$newcol = ($rr*$heightgb['red']) + ($br*$heightgb['blue']) + ($gr*$heightgb['green']);
$setcol = ImageColorAllocate($newGD, $newcol, $newcol, $newcol);
imagesetpixel($newGD, $dx, $dy, $setcol);
}
}
$output = clone $this;
$output->setImageResource($newGD);
return $output;
}
public function makeDir($dirname) {
if(!file_exists(dirname($dirname))) $this->makeDir(dirname($dirname));
if(!file_exists($dirname)) mkdir($dirname, Filesystem::$folder_create_mask);
}
public function writeTo($filename) {
$this->makeDir(dirname($filename));
if($filename) {
if(file_exists($filename)) list($width, $height, $type, $attr) = getimagesize($filename);
if(file_exists($filename)) unlink($filename);
$ext = strtolower(substr($filename, strrpos($filename,'.')+1));
if(!isset($type)) switch($ext) {
case "gif": $type = 1; break;
case "jpeg": case "jpg": case "jpe": $type = 2; break;
default: $type = 3; break;
}
// if the extension does not exist, the file will not be created!
switch($type) {
case 1: imagegif($this->gd, $filename); break;
case 2: imagejpeg($this->gd, $filename, $this->quality); break;
// case 3, and everything else
default:
// Save them as 8-bit images
// imagetruecolortopalette($this->gd, false, 256);
imagepng($this->gd, $filename); break;
}
if(file_exists($filename)) @chmod($filename,0664);
}
}
}
/**
* Backwards compatibility
*/
class GD extends GDBackend {
public static function set_default_quality($quality) {
Deprecation::notice(
'3.1',
'GDBackend::set_default_quality instead',
Deprecation::SCOPE_CLASS
);
GDBackend::set_default_quality($quality);
}
}