PHP生成GIF动态图片验证码
1 <?php 2 /** 3 * 调用示例 4 * */ 5 session_start(); 6 $randCode = ''; 7 //验证码随机 8 $str="abcdefghjkmnpqrstuvwsyzABCDEFGHJKMNPQRSTUVWSYZ23456789"; 9 for($i=0;$i<4;$i++){ 10 $safe.=substr($str,rand(0,strlen($str)),1); 11 } 12 $_SESSION["imgcode"]=$safe; 13 ImageCode($safe, 60); // 显示GIF动画 14 15 /** 16 * ImageCode 生成GIF图片验证 17 * @param $string 字符串 18 * @param $width 宽度 19 * @param $height 高度 20 * */ 21 function ImageCode($string = '', $width = 75, $height = 25){ 22 $authstr = $string ? $string : ((time() % 2 == 0) ? mt_rand(1000, 9999) : mt_rand(10000, 99999)); 23 $board_width = $width; 24 $board_height = $height; 25 // 生成一个32帧的GIF动画 26 for($i = 0; $i < 32; $i++){ 27 ob_start(); 28 $image = imagecreate($board_width, $board_height); 29 imagecolorallocate($image, 0,0,0); 30 // 设定文字颜色数组 31 $colorList[] = ImageColorAllocate($image, 15,73,210); 32 $colorList[] = ImageColorAllocate($image, 0,64,0); 33 $colorList[] = ImageColorAllocate($image, 0,0,64); 34 $colorList[] = ImageColorAllocate($image, 0,128,128); 35 $colorList[] = ImageColorAllocate($image, 27,52,47); 36 $colorList[] = ImageColorAllocate($image, 51,0,102); 37 $colorList[] = ImageColorAllocate($image, 0,0,145); 38 $colorList[] = ImageColorAllocate($image, 0,0,113); 39 $colorList[] = ImageColorAllocate($image, 0,51,51); 40 $colorList[] = ImageColorAllocate($image, 158,180,35); 41 $colorList[] = ImageColorAllocate($image, 59,59,59); 42 $colorList[] = ImageColorAllocate($image, 0,0,0); 43 $colorList[] = ImageColorAllocate($image, 1,128,180); 44 $colorList[] = ImageColorAllocate($image, 0,153,51); 45 $colorList[] = ImageColorAllocate($image, 60,131,1); 46 $colorList[] = ImageColorAllocate($image, 0,0,0); 47 $fontcolor = ImageColorAllocate($image, 0,0,0); 48 $gray = ImageColorAllocate($image, 245,245,245); 49 $color = imagecolorallocate($image, 255,255,255); 50 $color2 = imagecolorallocate($image, 255,0,0); 51 imagefill($image, 0, 0, $gray); 52 $space = 15;// 字符间距 53 if($i > 0){ // 屏蔽第一帧 54 for ($k = 0; $k < strlen($authstr); $k++) { 55 $colorRandom = mt_rand(0,sizeof($colorList)-1); 56 $float_top = rand(0,4); 57 $float_left = rand(0,3); 58 imagestring($image, 6, $space * $k, $top + $float_top, substr($authstr, $k, 1), $colorList[$colorRandom]); 59 } 60 } 61 for ($k = 0; $k < 20; $k++) { 62 $colorRandom = mt_rand(0,sizeof($colorList)-1); 63 imagesetpixel($image, rand()%70 , rand()%15 , $colorList[$colorRandom]); 64 65 } 66 // 添加干扰线 67 for($k = 0; $k < 5; $k++){ 68 $colorRandom = mt_rand(0, sizeof($colorList)-1); 69 // $todrawline = rand(0,1); 70 $todrawline = 1; 71 if($todrawline){ 72 imageline($image, mt_rand(0, $board_width), mt_rand(0,$board_height), mt_rand(0,$board_width), mt_rand(0,$board_height), $colorList[$colorRandom]); 73 }else{ 74 $w = mt_rand(0,$board_width); 75 $h = mt_rand(0,$board_width); 76 imagearc($image, $board_width - floor($w / 2) , floor($h / 2), $w, $h, rand(90,180), rand(180,270), $colorList[$colorRandom]); 77 } 78 } 79 imagegif($image); 80 imagedestroy($image); 81 $imagedata[] = ob_get_contents(); 82 ob_clean(); 83 ++$i; 84 } 85 $gif = new GIFEncoder($imagedata); 86 Header ('Content-type:image/gif'); 87 echo $gif->GetAnimation(); 88 } 89 90 91 /** 92 * GIFEncoder类 93 * */ 94 class GIFEncoder { 95 var $GIF = "GIF89a"; /* GIF header 6 bytes */ 96 var $VER = "GIFEncoder V2.06"; /* Encoder version */ 97 var $BUF = Array ( ); 98 var $LOP = 0; 99 var $DIS = 2; 100 var $COL = -1; 101 var $IMG = -1; 102 var $ERR = Array ( 103 'ERR00' =>"Does not supported function for only one image!", 104 'ERR01' =>"Source is not a GIF image!", 105 'ERR02' =>"Unintelligible flag ", 106 'ERR03' =>"Could not make animation from animated GIF source", 107 ); 108 function GIFEncoder ($GIF_src, $GIF_dly = 100, $GIF_lop = 0, $GIF_dis = 0, $GIF_red = 0, $GIF_grn = 0, $GIF_blu = 0, $GIF_mod = 'bin' ) { 109 if (!is_array($GIF_src) && !is_array($GIF_tim)) { 110 printf ( "%s: %s", $this->VER, $this->ERR['ERR00']); 111 exit( 0 ); 112 } 113 $this->LOP = ($GIF_lop > -1) ? $GIF_lop : 0; 114 $this->DIS = ($GIF_dis > -1) ? (( $GIF_dis < 3 ) ? $GIF_dis : 3) : 2; 115 $this->COL = ($GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1) ? ($GIF_red | ($GIF_grn << 8) | ($GIF_blu << 16)) : -1; 116 117 for ($i = 0, $src_count = count($GIF_src); $i < $src_count; $i++ ) { 118 if (strToLower( $GIF_mod ) == "url") { 119 $this->BUF[] = fread (fopen($GIF_src [$i], "rb"), filesize ($GIF_src [$i])); 120 }elseif(strToLower($GIF_mod) == "bin") { 121 $this->BUF [ ] = $GIF_src [ $i ]; 122 }else{ 123 printf("%s: %s ( %s )!", $this->VER, $this->ERR [ 'ERR02' ], $GIF_mod); 124 exit(0); 125 } 126 if (substr($this->BUF[$i], 0, 6) != "GIF87a" && substr($this->BUF [$i], 0, 6) != "GIF89a") { 127 printf( "%s: %d %s", $this->VER, $i, $this->ERR ['ERR01']); 128 exit(0); 129 } 130 for ($j = (13 + 3 * (2 << (ord($this->BUF[$i]{10}) & 0x07 ))), $k = TRUE; $k; $j++){ 131 switch ($this->BUF [$i]{$j}) { 132 case "!": 133 if ((substr($this->BUF[$i], ($j + 3), 8)) == "NETSCAPE") { 134 printf( "%s: %s ( %s source )!", $this->VER, $this->ERR ['ERR03'], ($i + 1)); 135 exit( 0 ); 136 } 137 break; 138 case ";": 139 $k = FALSE; 140 break; 141 } 142 } 143 } 144 GIFEncoder::GIFAddHeader(); 145 for($i = 0, $count_buf = count($this->BUF); $i < $count_buf; $i++) { 146 GIFEncoder::GIFAddFrames($i, $GIF_dly[$i]); 147 } 148 GIFEncoder::GIFAddFooter(); 149 } 150 151 function GIFAddHeader ( ) { 152 $cmap = 0; 153 if (ord($this->BUF[0]{10}) & 0x80 ) { 154 $cmap = 3 * ( 2 << ( ord ( $this->BUF [ 0 ]{10} ) & 0x07 )); 155 156 $this->GIF .= substr ( $this->BUF [ 0 ], 6, 7); 157 $this->GIF .= substr ( $this->BUF [ 0 ], 13, $cmap); 158 $this->GIF .= "!\377\13NETSCAPE2.0\3\1" . GIFEncoder::GIFWord ( $this->LOP ) . "\0"; 159 } 160 } 161 162 function GIFAddFrames ( $i, $d ) { 163 $Locals_str = 13 + 3 * (2 <<(ord($this->BUF[$i]{10}) & 0x07)); 164 $Locals_end = strlen($this->BUF[$i]) - $Locals_str - 1; 165 $Locals_tmp = substr ($this->BUF[$i], $Locals_str, $Locals_end); 166 $Global_len = 2 << (ord( $this->BUF [0]{10} ) & 0x07 ); 167 $Locals_len = 2 << (ord( $this->BUF[$i]{10}) & 0x07); 168 $Global_rgb = substr($this->BUF[0], 13, 3 * (2 << ( ord ( $this->BUF[0]{10} ) & 0x07))); 169 $Locals_rgb = substr ( $this->BUF[$i], 13, 3 * (2 << ( ord ( $this->BUF[$i]{10} ) & 0x07))); 170 $Locals_ext = "!\xF9\x04" . chr(($this->DIS << 2) + 0) . chr(($d >> 0) & 0xFF) . chr(($d >> 8) & 0xFF) . "\x0\x0"; 171 if ( $this->COL > -1 && ord($this->BUF[$i]{10}) & 0x80){ 172 for($j = 0; $j < (2 << (ord( $this->BUF[$i]{10}) & 0x07)); $j++ ) { 173 if(ord ($Locals_rgb{3 * $j + 0}) == ($this->COL >> 0) & 0xFF && ord ( $Locals_rgb { 3 * $j + 1 } ) == ( $this->COL >> 8 ) & 0xFF && ord ( $Locals_rgb { 3 * $j + 2 } ) == ( $this->COL >> 16 ) & 0xFF ) { 174 $Locals_ext = "!\xF9\x04" . chr(($this->DIS << 2) + 1) . chr (( $d >> 0) & 0xFF) . chr (( $d >> 8) & 0xFF) . chr ($j) . "\x0"; 175 break; 176 } 177 } 178 } 179 switch ( $Locals_tmp { 0 } ) { 180 case "!": 181 $Locals_img = substr($Locals_tmp, 8, 10); 182 $Locals_tmp = substr($Locals_tmp, 18, strlen ($Locals_tmp) - 18); 183 break; 184 case ",": 185 $Locals_img = substr($Locals_tmp, 0, 10); 186 $Locals_tmp = substr($Locals_tmp, 10, strlen($Locals_tmp) - 10); 187 break; 188 } 189 if ( ord ( $this->BUF[$i]{10} ) & 0x80 && $this->IMG > -1 ) { 190 if ( $Global_len == $Locals_len ) { 191 if ( GIFEncoder::GIFBlockCompare ( $Global_rgb, $Locals_rgb, $Global_len ) ) { 192 $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp ); 193 }else{ 194 $byte = ord ( $Locals_img{9}); 195 $byte |= 0x80; 196 $byte &= 0xF8; 197 $byte |= ( ord ( $this->BUF [ 0 ]{10}) & 0x07); 198 $Locals_img{9} = chr($byte); 199 $this->GIF .= ($Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp); 200 } 201 }else{ 202 $byte = ord($Locals_img{9}); 203 $byte |= 0x80; 204 $byte &= 0xF8; 205 $byte |= (ord($this->BUF[$i]{10}) & 0x07); 206 $Locals_img {9} = chr($byte); 207 $this->GIF .= ($Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp); 208 } 209 }else{ 210 $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp ); 211 } 212 $this->IMG = 1; 213 } 214 215 function GIFAddFooter ( ) { 216 $this->GIF .= ";"; 217 } 218 219 function GIFBlockCompare ( $GlobalBlock, $LocalBlock, $Len ) { 220 for ( $i = 0; $i < $Len; $i++ ) { 221 if($GlobalBlock { 3 * $i + 0 } != $LocalBlock { 3 * $i + 0 } || $GlobalBlock { 3 * $i + 1 } != $LocalBlock { 3 * $i + 1 } || $GlobalBlock { 3 * $i + 2 } != $LocalBlock{3 * $i + 2}) { 222 return ( 0 ); 223 } 224 } 225 return ( 1 ); 226 } 227 228 function GIFWord ( $int ) { 229 return ( chr ( $int & 0xFF ) . chr ( ( $int >> 8 ) & 0xFF ) ); 230 } 231 232 function GetAnimation ( ) { 233 return ($this->GIF); 234 } 235 }