I have used some image resize functions implemented in PHP, but they are not perfect. Some pictures are completely deformed after adjustment, and some have more lines for no reason, and some have poor color brightness. Not satisfactory either. Today I searched again and gained some more results.
if(isset($_FILES['manager_photo']) && !empty($_FILES['manager_photo']['name']))
{
$photo_name=$manager_name."-".$_FILES["manager_photo"]["name"];
$tmpname = $_FILES['manager_photo']['tmp_name'];
$file_ext= substr($photo_name, strripos($photo_name, '.'));
$dir = "./manager_photos/";
// finally resize
@img_resize( $tmpname , 90 , $dir , $photo_name, 1);
}
function img_resize( $tmpname, $size, $save_dir, $save_name, $maxisheight = 0 )
{
$save_dir .= ( substr($save_dir,-1) != "/") ? "/" : "";
$gis = getimagesize($tmpname);
$type = $gis[2];
switch($type)
{
case "1": $imorig = imagecreatefromgif($tmpname); break;
case "2": $imorig = imagecreatefromjpeg($tmpname);break;
case "3": $imorig = imagecreatefrompng($tmpname); break;
default: $imorig = imagecreatefromjpeg($tmpname);
}
$x = imagesx($imorig);
$y = imagesy($imorig);
$woh = (!$maxisheight)? $gis[0] : $gis[1] ;
if($woh <= $size)
{
$aw = $x;
$ah = $y;
}
else
{
if(!$maxisheight){
$aw = $size;
$ah = $size * $y / $x;
} else {
$aw = $size * $x / $y;
$ah = $size;
}
}
$im = imagecreatetruecolor($aw,$ah);
if (imagecopyresampled($im,$imorig , 0,0,0,0,$aw,$ah,$x,$y))
if (imagejpeg($im, $save_dir.$save_name))
return true;
else
return false;
}//img_resizeUse ImageMagick to implement it
Someone mentioned using ImageMagick to implement it. There are many options in it, and we can achieve image adjustment with very little code. Worth studying.
$image = new Imagick($src); $image->resizeImage($width,$height,Imagick::FILTER_LANCZOS,1); $image->cropImage($width_2, $height_2, $x, $y); $image->setCompression(Imagick::COMPRESSION_JPEG); $image->setImageCompressionQuality(82); $image->writeImage($dest); $image->destroy();
Use php_class_upload to implement
If the above introduction is not suitable for you, you can not only upload and adjust images, but also cut, cut, add watermarks, rotate, flip, etc.
Other implementation code reference
This code can return the picture and the correct name, but can it only be black?
function resize($originalImage){
list($width, $height) = getimagesize($originalImage);
$newName=basename($originalImage);
$imageResized = imagecreatetruecolor(128, 128);
$imageTmp = imagecreatefromjpeg($originalImage);
imagecopyresampled($imageResized, $imageTmp, 0, 0, 0, 0, 128, 128, $width, $height);
imagejpeg($imageResized, "resizedImg/$newName",100);
imageDestroy($imageResized);
}After the code is improved, look at the following code to set the color.
function resizeImage($file){
define ('MAX_WIDTH', 1500);//max image width
define ('MAX_HEIGHT', 1500);//max image height
define ('MAX_FILE_SIZE', 10485760);
//iamge save path
$path = 'storeResize/';
//size of the resize image
$new_width = 128;
$new_height = 128;
//name of the new image
$nameOfFile = 'resize_'.$new_width.'x'.$new_height.'_'.basename($file['name']);
$image_type = $file['type'];
$image_size = $file['size'];
$image_error = $file['error'];
$image_file = $file['tmp_name'];
$image_name = $file['name'];
$image_info = getimagesize($image_file);
//check image type
if ($image_info['mime'] == 'image/jpeg' or $image_info['mime'] == 'image/jpg'){
}
else if ($image_info['mime'] == 'image/png'){
}
else if ($image_info['mime'] == 'image/gif'){
}
else{
//set error invalid file type
}
if ($image_error){
//set error image upload error
}
if ( $image_size > MAX_FILE_SIZE ){
//set error image size invalid
}
switch ($image_info['mime']) {
case 'image/jpg': //This isn't a valid mime type so we should probably remove it
case 'image/jpeg':
$image = imagecreatefromjpeg ($image_file);
break;
case 'image/png':
$image = imagecreatefrompng ($image_file);
break;
case 'image/gif':
$image = imagecreatefromgif ($image_file);
break;
}
if ($new_width == 0 && $new_height == 0) {
$new_width = 100;
$new_height = 100;
}
// ensure size limits can not be abused
$new_width = min ($new_width, MAX_WIDTH);
$new_height = min ($new_height, MAX_HEIGHT);
//get original image h/w
$width = imagesx ($image);
$height = imagesy ($image);
//$align = 'b';
$zoom_crop = 1;
$origin_x = 0;
$origin_y = 0;
//TODO setting Memory
// generate new w/h if not provided
if ($new_width && !$new_height) {
$new_height = floor ($height * ($new_width / $width));
} else if ($new_height && !$new_width) {
$new_width = floor ($width * ($new_height / $height));
}
// scale down and add borders
if ($zoom_crop == 3) {
$final_height = $height * ($new_width / $width);
if ($final_height > $new_height) {
$new_width = $width * ($new_height / $height);
} else {
$new_height = $final_height;
}
}
// create a new true color image
$canvas = imagecreatetruecolor ($new_width, $new_height);
imagealphablending ($canvas, false);
if (strlen ($canvas_color) < 6) {
$canvas_color = 'ffffff';
}
$canvas_color_R = hexdec (substr ($canvas_color, 0, 2));
$canvas_color_G = hexdec (substr ($canvas_color, 2, 2));
$canvas_color_B = hexdec (substr ($canvas_color, 2, 2));
// Create a new transparent color for image
$color = imagecolorallocatealpha ($canvas, $canvas_color_R, $canvas_color_G,$canvas_color_B, 127);
// Completely fill the background of the new image with allocated color.
imagefill ($canvas, 0, 0, $color);
// scale down and add borders
if ($zoom_crop == 2) {
$final_height = $height * ($new_width / $width);
if ($final_height > $new_height) {
$origin_x = $new_width / 2;
$new_width = $width * ($new_height / $height);
$origin_x = round ($origin_x - ($new_width / 2));
} else {
$origin_y = $new_height / 2;
$new_height = $final_height;
$origin_y = round ($origin_y - ($new_height / 2));
}
}
// Restore transparency blending
imagesavealpha ($canvas, true);
if ($zoom_crop > 0) {
$src_x = $src_y = 0;
$src_w = $width;
$src_h = $height;
$cmp_x = $width / $new_width;
$cmp_y = $height / $new_height;
// calculate x or y coordinate and width or height of source
if ($cmp_x > $cmp_y) {
$src_w = round ($width / $cmp_x * $cmp_y);
$src_x = round (($width - ($width / $cmp_x * $cmp_y)) / 2);
} else if ($cmp_y > $cmp_x) {
$src_h = round ($height / $cmp_y * $cmp_x);
$src_y = round (($height - ($height / $cmp_y * $cmp_x)) / 2);
}
// positional cropping!
if ($align) {
if (strpos ($align, 't') !== false) {
$src_y = 0;
}
if (strpos ($align, 'b') !== false) {
$src_y = $height - $src_h;
}
if (strpos ($align, 'l') !== false) {
$src_x = 0;
}
if (strpos ($align, 'r') !== false) {
$src_x = $width - $src_w;
}
}
// positional cropping!
imagecopyresampled ($canvas, $image, $origin_x, $origin_y, $src_x, $src_y, $new_width, $new_height, $src_w, $src_h);
} else {
imagecopyresampled ($canvas, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
}
//Straight from Wordpress core code. Reduces filesize by up to 70% for PNG's
if ( (IMAGETYPE_PNG == $image_info[2] || IMAGETYPE_GIF == $image_info[2]) && function_exists('imageistruecolor') && !imageistruecolor( $image ) && imagecolortransparent( $image ) > 0 ){
imagetruecolortopalette( $canvas, false, imagecolorstotal( $image ) );
}
$quality = 100;
$nameOfFile = 'resize_'.$new_width.'x'.$new_height.'_'.basename($file['name']);
if (preg_match('/^image\/(?:jpg|jpeg)$/i', $image_info['mime'])){
imagejpeg($canvas, $path.$nameOfFile, $quality);
} else if (preg_match('/^image\/png$/i', $image_info['mime'])){
imagepng($canvas, $path.$nameOfFile, floor($quality * 0.09));
} else if (preg_match('/^image\/gif$/i', $image_info['mime'])){
imagegif($canvas, $path.$nameOfFile);
}
}The above is the detailed content of Detailed explanation of image resize function in PHP to adjust image size. For more information, please follow other related articles on the PHP Chinese website!
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