PHP thumbnails and other proportional lossless compression, can fill the blank area to supplement the color

PHP thumbnails and other proportional lossless compression, can fill the blank area to fill the color of the implementation code, you can refer to the need for friends. Copy codeThe code is as follows:
Error_reporting (E_ALL );
// Test
Imagezoom('1.jpg ', '2.jpg', 400,300, '# ffff ');
/*
Php thumbnail function:
Proportional lossless compression, can be filled with complementary colors author: Huatai
Host format:
Bmp, jpg, gif, and png
Param:
@ Srcimage: the image to be reduced
@ Dstimage: the image to be saved
@ Dst_width: narrowing down the width
@ Dst_height: zoom in and out
@ Backgroundcolor: complementary colors such as: # FFFFFF supports 6 bits and does not support 3 bits
*/
Function imagezoom ($ srcimage, $ dstimage, $ dst_width, $ dst_height, $ backgroundcolor ){
// The file name is garbled
If (PHP_ OS = 'winnt '){
$ Srcimage = iconv ('utf-8', 'gbk', $ srcimage );
$ Dstimage = iconv ('utf-8', 'gbk', $ dstimage );
}
$ Dstimg = imagecreatetruecolor ($ dst_width, $ dst_height );
$ Color = imagecolorallocate ($ dstimg
, Hexdec (substr ($ backgroundcolor, 1, 2 ))
, Hexdec (substr ($ backgroundcolor, 3, 2 ))
, Hexdec (substr ($ backgroundcolor, 5, 2 ))
);
Imagefill ($ dstimg, 0, 0, $ color );
If (! $ Arr = getimagesize ($ srcimage )){
Echo "the file to generate the thumbnail does not exist ";
Exit;
}
$ Src_width = $ arr [0];
$ Src_height = $ arr [1];
$ Srcimg = null;
$ Method = getcreatemethod ($ srcimage );
If ($ method ){
Eval ('$ srcimg ='. $ method .';');
}
$ Dst_x = 0;
$ Dst_y = 0;
$ Dst_w = $ dst_width;
$ Dst_h = $ dst_height;
If ($ dst_width/$ dst_height-$ src_width/$ src_height)> 0 ){
$ Dst_w = $ src_width * ($ dst_height/$ src_height );
$ Dst_x = ($ dst_width-$ dst_w)/2;
} Elseif ($ dst_width/$ dst_height-$ src_width/$ src_height) <0 ){
$ Dst_h = $ src_height * ($ dst_width/$ src_width );
$ Dst_y = ($ dst_height-$ dst_h)/2;
}
Imagecopyresampled ($ dstimg, $ srcimg, $ dst_x
, $ Dst_y, 0, 0, $ dst_w, $ dst_h, $ src_width, $ src_height );
// Save the format
$ Arr = array (
'Jpg '=> 'imagejpeg'
, 'Jpeg '=> 'imagejpeg'
, 'PNG '=> 'imagepng'
, 'GIF' => 'imagegif'
, 'Bmp '=> 'imagebmp'
);
$ Suffix = strtolower (array_pop (explode ('.', $ dstimage )));
If (! In_array ($ suffix, array_keys ($ arr ))){
Echo "an error occurred while saving the file name ";
Exit;
} Else {
Eval ($ arr [$ suffix]. '($ dstimg, "'. $ dstimage .'");');
}
Imagejpeg ($ dstimg, $ dstimage );
Imagedestroy ($ dstimg );
Imagedestroy ($ srcimg );
}
Function getcreatemethod ($ file ){
$ Arr = array (
'000000' => "imagecreatefromgif ('$ file ')"
, 'Ffd8ff' => "imagecreatefromjpeg ('$ file ')"
, 'Mongod' => "imagecreatefrombmp ('$ file ')"
, '89504e '=> "imagecreatefrompng (' $ file ')"
);
$ Fd = fopen ($ file, "rb ");
$ Data = fread ($ fd, 3 );
$ Data = str2hex ($ data );
If (array_key_exists ($ data, $ arr )){
Return $ arr [$ data];
} Elseif (array_key_exists (substr ($ data, 0, 4), $ arr )){
Return $ arr [substr ($ data, 0, 4)];
} Else {
Return false;
}
}
Function str2hex ($ str ){
$ Ret = "";
For ($ I = 0; $ I <strlen ($ str); $ I ++ ){
$ Ret. = ord ($ str [$ I])> = 16? Strval (dechex (ord ($ str [$ I])
: '0'. strval (dechex (ord ($ str [$ I]);
}
Return strtoupper ($ ret );
}
// The BMP creation function does not exist in php.
Function imagecreatefrombmp ($ filename)
{
If (! $ F1 = fopen ($ filename, "rb") return FALSE;
$ FILE = unpack ("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread ($ f1, 14 ));
If ($ FILE ['File _ type']! = 19778) return FALSE;
$ 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 ['Colors '] = 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_pixel2 '] = 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 ['demo'] = 0;
$ PALETTE = array ();
If ($ BMP ['Colors '] <16777216)
{
$ PALETTE = unpack ('v'. $ BMP ['Colors '], fread ($ f1, $ BMP ['Colors'] * 4 ));
}
$ IMG = fread ($ f1, $ BMP ['size _ bitmap']);
$ VIDE = chr (0 );
$ Res = imagecreatetruecolor ($ 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];
}
Else
Return FALSE;
Imagesetpixel ($ res, $ X, $ Y, $ COLOR [1]);
$ X ++;
$ P + = $ BMP ['bytes _ per_pixel '];
}
$ Y --;
$ P + = $ BMP ['demo'];
}
Fclose ($ f1 );
Return $ res;
}
// BMP save function, which is not available in php
Function imagebmp ($ im, $ fn = false)
{
If (! $ Im) return false;
If ($ fn = false) $ fn = 'php: // output ';
$ F = fopen ($ fn, "w ");
If (! $ F) return false;
$ BiWidth = imagesx ($ im );
$ BiHeight = imagesy ($ im );
$ BiBPLine = $ biWidth * 3;
$ BiStride = ($ biBPLine + 3 )&~ 3;
$ BiSizeImage = $ biStride * $ biHeight;
$ BfOffBits = 54;
$ BfSize = $ bfOffBits + $ biSizeImage;
Fwrite ($ f, 'bm ', 2 );
Fwrite ($ f, pack ('vvvv ', $ bfSize, 0, 0, $ bfOffBits ));
Fwrite ($ f, pack ('vvvvvvvvvvv ', 40, $ biWidth, $ biHeight, 1, 24, 0, $ biSizeImage, 0, 0, 0, 0 ));
$ Numpad = $ biStride-$ biBPLine;
For ($ y = $ biHeight-1; $ y> = 0; -- $ y)
{
For ($ x = 0; $ x <$ biWidth; ++ $ x)
{
$ Col = imagecolorat ($ im, $ x, $ y );
Fwrite ($ f, pack ('v', $ col), 3 );
}
For ($ I = 0; $ I <$ numpad; ++ $ I)
Fwrite ($ f, pack ('C', 0 ));
}
Fclose ($ f );
Return true;
}
?>