php產生影像縮圖（支援：JPEG，GIT，PNG，BMP）-php教程-PHP中文網

php產生影像縮圖（支援：JPEG，GIT，PNG，BMP）

WBOY

發布： 2016-07-25 08:45:09

原創

1315 人瀏覽過

class Thumb
{
public function create($srcPath, $dstPath, $dstWidth, $dstHeight)
if (!file_exists($srcPath)) {
return false;
}
@$srcSize = getimagesize($srcPath);
if (empty($srcSize)) {
return false;
}
$srcWith = intval($srcSize[0]);
$srcHeight = intval($srcSize[1]);
$srcHeight = intval($srcSize[1]);
//如果原始圖片的尺寸大於指定縮圖的尺寸，則產生縮圖，否則拷貝原始圖片
if ($srcWith return copy($ srcPath, $dstPath);
}
//讀取原始圖片資源
@$srcImage = imagecreatefromjpeg($srcPath);
if (empty($srcImage)) { @$srcImage = imagecreatefromgif($srcPath);
}
if (empty($srcImage)) {
@$srcImage = imagecreatefrompng($srcPath);
}
}
);
} @$srcImage = $this->_imageCreateFromBMP($srcPath);
}
if (empty($srcImage)) {
if (empty($srcImage)) {
if (empty($srcImage)) {
}
//取得縮圖的尺寸，並據此產生新的圖片
$dstSize = $this->_getDstSize(
$srcWith, $srcHeight, $dstWidth, $dstHeight
);
@$dstImage = imagecreatetruecolor(
$dstSize['width'], $dstSize['height']
);
$dstImage, $srcImage , 0, 0, 0, 0,
$dstSize['width'], $dstSize['height'],
$srcWith, $srcHeight
);
$srcWith, $srcHeight
);
);
return @imagepng($srcPath, $dstPath);
}
private function _imageCreateFromBMP($filePath)
{
$fileHandle = fopendfilePath, 'fileHandle ;
if (empty($fileHandle)) {
return false;
}
$file = unpack(
'vfile_type/Vfile_size/Vreserved/Vbitmap(
'vfile_type/Vfile_size/Vreserved/Vbitmap_offset' fread($fileHandle, 14)
);
if ($file['file_type'] != 19778) {
return false;
}
'Vheader_size/Vwidth/Vheight/vplanes/'.
'vbits_per_pixel/Vcompression/Vsize_bitmap/'.
'Vhoriz_resolution/Vcolor_resperatution/Vcolor_fidofsed(3)(3D), fidunc_resport) 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['decal'] = $bmp['width'] * $bmp['bytes_per_pixel'] / 4 ;
$bmp['decal'] -= floor($bmp['width'] * $bmp['bytes_per_pixel'] / 4);
$bmp['decal'] = 4 - (4 * $bmp['decal']);
if ($bmp['decal'] == 4) {
$bmp['decal'] = 0;
}
$ palette = array();
if ($bmp['colors'] $palette = unpack(
'V' . $bmp['colors'],
fread( $fileHandle, $bmp['colors'] * 4)
);
}
$image = fread($fileHandle, $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 if ($bmp[ 'bits_per_pixel'] == 24) {
$color = unpack('V', substr($image, $p, 3) . $vide);
} else if ($bmp['bits_per_pixel'] == 16) {
$color = unpack('n', substr($image, $p, 2));
$color[1] = $palette[$color[1] 1];
} else if ($bmp['bits_per_pixel'] == 8) {
$color = unpack('n', $vide . substr ($image, $p, 1));
$color [1] = $palette[$color[1] 1];
} else if ($bmp['bits_per_pixel'] ==4) {
$color = unpack('n', $vide . substr ($image, 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] ; }else if ($bmp['bits_per_pixel'] == 1) {
$color = unpack('n', $vide . substr($image, Floor($p), 1));
switch ( ($p * 8) % 8) {
情況0:
$color[1] = ($color[1] >> 7);
中斷;
情況1:
$color[1] = ($color[1] & 0x40) >>> 6;
中斷;
情況2:
$color[1] = ($color[1] & 0x20) > >> 5;
中斷;
情況3:
$color[1] = ($color[1] & 0x10) >>> 4;
中斷;
情況4:
$color[1] = ($color[1] & 0x8) >>> 3;
中斷;
情況5:
$color[1] = ($color[1] & 0x4 ) >>> 2;
中斷;
情況6:
$color[1] = ($color[1] & 0x2) >>> 1;
中斷;
情況7 :
$color[1] = ($color[1] & 0x1);
中斷;
}
$color[1] = $palette[$color[1] 1];
} else {
return false;
}
imagesetpixel($res, $x, $y, $color[1]);
$x ;
$p = $bmp ['bytes_per_pixel'];
}
$y--;
$p = $bmp['decal'];
}
fclose($fileHandle);
return $ res;
}
private function _getDstSize($srcWith, $srcHeight, $dstWidth, $dstHeight)
{
$size = array('width' = 'ight ' => $srcHeight);
if ($dstWidth > 0 && $dstHeight > 0) {
if ($srcWith > 0 && $srcHeight > 0) {
if ($srcWith / $srcHeight > 0) {
if ($srcWith / $srcHeight > = $dstWidth / $dstHeight) {
if ($srcWith >; $dstWidth) {
$size['width'] = $dstWidth;
$size['height'] = $srcHeight * $srcHeight * dstWidth / $srcWith;
}
} else {
if ($srcHeight > $dstHeight) {
$size['width'] = $srcWith * $dstHeight / $srcight; $size['height'] = $dstHeight;
}
}
}
}
return $size;
}
}

複製程式碼

JPEG、PHP、GIT