Php implementation of image thumbnails, _ PHP Tutorial

Php implements image thumbnails ,. Php implements image thumbnails. the code in this section provides the following functions: jpg, jpeg, gif, png, and bmp image formats. you can scale the image according to the proportion of the original image, you can choose to scale the php image to implement image thumbnails,

The functions of this code include:

Jpg, jpeg, gif, png, and bmp image formats are supported. you can scale the image according to the original image proportion. you can select whether to crop the image during image scaling, added image quality control to achieve the highest quality of the thumbnail.

The complete class code is as follows:

<? Php/*** function: php class for generating thumbnail slices */class ResizeImage {public $ type; // image type public $ width; // actual width public $ height; // actual height public $ resize_width; // The width public $ resize_height after the change; // The height public $ cut after the change; // whether to cut the image public $ srcimg; // source image public $ dstimg; // target Image address public $ im; // temporary Image public $ quality; // image quality function resizeimage ($ img, $ wid, $ hei, $ c, $ dstpath, $ quality = 100) {$ this-> srcimg = $ img; $ this-> resize_width = $ wid; $ this-> resize_height = $ hei; $ thi S-> cut = $ c; $ this-> quality = $ quality; $ this-> type = strtolower (substr (strrchr ($ this-> srcimg ,'. '), 1); // the image type $ this-> initi_img (); // initialize the image $ this-> dst_img ($ dstpath ); // target Image address @ $ this-> width = imagesx ($ this-> im); @ $ this-> height = imagesy ($ this-> im ); $ this-> newimg (); // generates an image @ ImageDestroy ($ this-> im);} function newimg () {$ resize_ratio = ($ this-> resize_width) /($ this-> resize_height); // ratio of the changed image @ $ ratio = ($ this-> width)/($ this-> hei Ght); // ratio of the actual image if ($ this-> cut) = '1 ') {// Cut image if ($ img_func = 'imagepng '& (str_replace ('. ', '', PHP_VERSION)> = 512) {// processing status after the php version is greater than 5.12 parameter change $ quality = 9 ;} if ($ ratio >=$ resize_ratio) {// high priority $ newimg = imagecreatetruecolor ($ this-> resize_width, $ this-> resize_height); imagecopyresampled ($ newimg, $ this-> im, 0, 0, 0, $ this-> resize_width, $ this-> resize_height, ($ this-> height) * $ resize_ratio ), $ this-> height); imagejpeg ($ newimg, $ This-> dstimg, $ this-> quality);} if ($ ratio <$ resize_ratio) {// width first $ newimg = imagecreatetruecolor ($ this-> resize_width, $ this-> resize_height); imagecopyresampled ($ newimg, $ this-> im, 0, 0, 0, $ this-> resize_width, $ this-> resize_height, $ this-> width, ($ this-> width)/$ resize_ratio); imagejpeg ($ newimg, $ this-> dstimg, $ this-> quality );}} else {// no picture if ($ ratio >=$ resize_ratio) {$ newimg = imagecreatetruecolor ($ this-> resize_width, ($ This-> resize_width)/$ ratio); imagecopyresampled ($ newimg, $ this-> im, 0, 0, 0, $ this-> resize_width, ($ this-> resize_width) /$ ratio, $ this-> width, $ this-> height); imagejpeg ($ newimg, $ this-> dstimg, $ this-> quality );} if ($ ratio <$ resize_ratio) {$ newimg = imagecreatetruecolor ($ this-> resize_height) * $ ratio, $ this-> resize_height); @ imagecopyresampled ($ newimg, $ this-> im, 0, 0, 0, ($ this-> resize_height) * $ ratio, $ this-> resize_heig Ht, $ this-> width, $ this-> height); @ imagejpeg ($ newimg, $ this-> dstimg, $ this-> quality );}}} function initi_img () {// initialize the image if ($ this-> type = 'jpg '| $ this-> type = 'jpeg ') {$ this-> im = imagecreatefromjpeg ($ this-> srcimg);} if ($ this-> type = 'GIF ') {$ this-> im = imagecreatefromgif ($ this-> srcimg);} if ($ this-> type = 'PNG ') {$ this-> im = imagecreatefrompng ($ this-> srcimg);} if ($ this-> type = 'wbm ') {@ $ this-> im = imagecreatefromwbmp ($ this-> Srcimg);} if ($ this-> type = 'bmp ') {$ this-> im = $ this-> ImageCreateFromBMP ($ this-> srcimg );}} function dst_img ($ dstpath) {// Image destination address $ full_length = strlen ($ this-> srcimg); $ type_length = strlen ($ this-> type ); $ name_length = $ full_length-$ type_length; $ name = substr ($ this-> srcimg, 0, $ name_length-1); $ this-> dstimg = $ dstpath; // echo $ this-> dstimg;} function ImageCreateFromBMP ($ filename) {// custom function to process bmp image if (! $ F1 = fopen ($ filename, "rb") returnFALSE; $ FILE = unpack ("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread ($ f1, 14 )); if ($ FILE ['File _ type']! = 19778) returnFALSE; $ BMP = unpack ('vheader _ size/Vwidth/Vheight/vplanes/vbits_per_pixel '. '/Vcompression/Vsize_bitmap/Vhoriz_resolution '. '/Vvert_resolution/Vcolors_used/Vcolors_important', fread ($ f1, 40); $ BMP ['color'] = pow (2, $ BMP ['bits _ per_pixel ']); if ($ BMP ['size _ bitmap'] = 0) $ BMP ['size _ bitmap'] = $ FILE ['File _ size']-$ file ['bitmap _ offset']; $ BMP ['bytes _ per_pixel '] = $ BMP ['bits _ per_pixel']/8; $ BMP ['bytes _ per_pixel 2'] = ceil ($ BMP ['bytes _ per_pixel ']); $ BMP ['desc'] = ($ BMP ['width'] * $ BMP ['bytes _ per_pixel ']/4 ); $ BMP ['desc']-= floor ($ BMP ['width'] * $ BMP ['bytes _ per_pixel ']/4 ); $ BMP ['demo'] = 4-(4 * $ BMP ['demo']); if ($ BMP ['demo'] = 4) $ BMP ['desc'] = 0; $ PALETTE = array (); if ($ BMP ['color'] <16777216) {$ PALETTE = unpack ('V '. $ BMP ['Colors '], fread ($ f1, $ BMP ['Colors'] * 4);} $ IMG = fread ($ f1, $ BMP ['size _ bitmap']); $ VIDE = chr (0); $ res = imagecreatetru Ecolor ($ BMP ['width'], $ BMP ['height']); $ P = 0; $ Y = $ BMP ['height']-1; while ($ Y> = 0) {$ X = 0; while ($ X <$ BMP ['width']) {if ($ BMP ['bits _ per_pixel '] = 24) $ COLOR = unpack ("V", substr ($ IMG, $ P, 3 ). $ VIDE); elseif ($ BMP ['bits _ per_pixel '] = 16) {$ COLOR = unpack ("n", substr ($ IMG, $ P, 2); $ COLOR [1] = $ PALETTE [$ COLOR [1] + 1];} elseif ($ BMP ['bits _ per_pixel '] = 8) {$ COLOR = unpack ("n", $ VIDE. substr ($ IMG, $ P, 1); $ COLOR [1] = $ PALETTE [$ COLOR [1] + 1];} elseif ($ BMP ['bits _ per_pixel '] = 4) {$ COLOR = unpack ("n", $ VIDE. substr ($ IMG, floor ($ P), 1); if ($ P * 2) % 2 = 0) $ COLOR [1] = ($ COLOR [1]> 4); else $ COLOR [1] = ($ COLOR [1] & 0x0F ); $ COLOR [1] = $ PALETTE [$ COLOR [1] + 1];} elseif ($ BMP ['bits _ per_pixel '] = 1) {$ COLOR = unpack ("n", $ VIDE. substr ($ IMG, floor ($ P), 1); if ($ P * 8) % 8 = 0) $ COLOR [1] = $ COLOR [1]> 7; elseif ($ P * 8) % 8 = 1) $ COLOR [1] = ($ COLOR [1] & 0x40)> 6; elseif ($ P * 8) % 8 = 2) $ COLOR [1] = ($ COLOR [1] & 0x20)> 5; Elseif ($ P * 8) % 8 = 3) $ COLOR [1] = ($ COLOR [1] & 0x10)> 4; elseif ($ P * 8) % 8 = 4) $ COLOR [1] = ($ COLOR [1] & 0x8)> 3; elseif ($ P * 8) % 8 = 5) $ COLOR [1] = ($ COLOR [1] & 0x4)> 2; elseif ($ P * 8) % 8 = 6) $ COLOR [1] = ($ COLOR [1] & 0x2)> 1; elseif ($ P * 8) % 8 = 7) $ COLOR [1] = ($ COLOR [1] & 0x1 ); $ COLOR [1] = $ PALETTE [$ COLOR [1] + 1];} elsereturnFALSE; imagesetpixel ($ res, $ X, $ Y, $ COLOR [1]); $ X ++; $ P + = $ BMP ['bytes _ per_pixel '];} $ Y --; $ P + = $ BMP ['demo'];} fclose ($ f1); return $ Res ;}}?>

The usage code is as follows:

$resizeimage=new ResizeImage('upload/abc.bmp', '120', '90', '0', 'upload/xabc.bmp');

The above code is a small Editor to share with you the php method to implement image thumbnails, I hope to help you!

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The following code provides the following functions: jpg, jpeg, gif, png, and bmp image formats are supported. you can scale the image according to the proportion of the original image...