php将bmp格式图片转换成jpg格式程序
function imagebmp( $img , $file = "" , $rle =0) { $colorcount =imagecolorstotal( $img ); $transparent =imagecolortransparent( $img ); $istransparent = $transparent !=-1; if ( $istransparent ) $colorcount --; if ( $colorcount ==0) { $colorcount =0; $bitcount =24;}; if (( $colorcount >0) and ( $colorcount <=2)) { $colorcount =2; $bitcount =1;}; if (( $colorcount >2) and ( $colorcount <=16)) { $colorcount =16; $bitcount =4;}; if (( $colorcount >16) and ( $colorcount <=256)) { $colorcount =0; $bitcount =8;}; $width =imagesx( $img ); $height =imagesy( $img ); $zbytek =(4-( $width /(8/ $bitcount ))%4)%4; if ( $bitcount <24) $palsize =pow(2, $bitcount )*4; $size =( floor ( $width /(8/ $bitcount ))+ $zbytek )* $height +54; $size += $palsize ; $offset =54+ $palsize ; // bitmap file header $ret = 'bm' ; // header (2b) $ret .= int_to_dword( $size ); // size of file (4b) $ret .= int_to_dword(0); // reserved (4b) $ret .= int_to_dword( $offset ); // byte location in the file which is first byte of image (4b) // bitmap info header $ret .= int_to_dword(40); // size of bitmapinfoheader (4b) $ret .= int_to_dword( $width ); // width of bitmap (4b) $ret .= int_to_dword( $height ); // height of bitmap (4b) $ret .= int_to_word(1); // biplanes = 1 (2b) $ret .= int_to_word( $bitcount ); // bibitcount = {1 (mono) or 4 (16 clr ) or 8 (256 clr) or 24 (16 mil)} (2b) $ret .= int_to_dword( $rle ); // rle compression (4b) $ret .= int_to_dword(0); // width x height (4b) $ret .= int_to_dword(0); // bixpelspermeter (4b) $ret .= int_to_dword(0); // biypelspermeter (4b) $ret .= int_to_dword(0); // number of palettes used (4b) $ret .= int_to_dword(0); // number of important colour (4b) // image data $cc = $colorcount ; $sl1 = strlen ( $ret ); if ( $cc ==0) $cc =256; if ( $bitcount <24) { $colortotal =imagecolorstotal( $img ); if ( $istransparent ) $colortotal --; for ( $p =0; $p < $colortotal ; $p ++) { $color =imagecolorsforindex( $img , $p ); $ret .=inttobyte( $color [ "blue" ]); $ret .=inttobyte( $color [ "green" ]); $ret .=inttobyte( $color [ "red" ]); $ret .=inttobyte(0); //reserved }; $ct = $colortotal ; for ( $p = $colortotal ; $p < $cc ; $p ++) { $ret .=inttobyte(0); $ret .=inttobyte(0); $ret .=inttobyte(0); $ret .=inttobyte(0); //reserved }; }; if ( $bitcount <=8) { for ( $y = $height -1; $y >=0; $y --) { $bwrite = "" ; for ( $x =0; $x < $width ; $x ++) { $color =imagecolorat( $img , $x , $y ); $bwrite .=decbinx( $color , $bitcount ); if ( strlen ( $bwrite )==8) { $retd .=inttobyte( bindec ( $bwrite )); $bwrite = "" ; }; }; if (( strlen ( $bwrite )<8) and ( strlen ( $bwrite )!=0)) { $sl = strlen ( $bwrite ); for ( $t =0; $t <8- $sl ; $t ++) $sl .= "0" ; $retd .=inttobyte( bindec ( $bwrite )); }; for ( $z =0; $z < $zbytek ; $z ++) $retd .=inttobyte(0); }; }; if (( $rle ==1) and ( $bitcount ==8)) { for ( $t =0; $t < strlen ( $retd ); $t +=4) { if ( $t !=0) if (( $t )% $width ==0) $ret .= chr (0). chr (0); if (( $t +5)% $width ==0) { $ret .= chr (0). chr (5). substr ( $retd , $t ,5). chr (0); $t +=1; } if (( $t +6)% $width ==0) { $ret .= chr (0). chr (6). substr ( $retd , $t ,6); $t +=2; } else { $ret .= chr (0). chr (4). substr ( $retd , $t ,4); }; }; $ret .= chr (0). chr (1); } else { $ret .= $retd ; }; if ( $bitcount ==24) { for ( $z =0; $z < $zbytek ; $z ++) $dopl .= chr (0); for ( $y = $height -1; $y >=0; $y --) { for ( $x =0; $x < $width ; $x ++) { $color =imagecolorsforindex( $img ,imagecolorat( $img , $x , $y )); $ret .= chr ( $color [ "blue" ]). chr ( $color [ "green" ]). chr ( $color [ "red" ]); } $ret .= $dopl ; }; }; if ( $file != "" ) { $r =( $f = fopen ( $file , "w" )); $r = $r and fwrite( $f , $ret ); $r = $r and fclose( $f ); return $r ; } else { echo $ret ; }; }; /* *------------------------------------------------------------ * imagecreatefrombmp *------------------------------------------------------------ * - reads image from a bmp file * * parameters: $file - target file to load * * returns: image id */ function imagecreatefrombmp( $file ) { global $currentbit , $echomode ; $f = fopen ( $file , "r" ); $header = fread ( $f ,2); if ( $header == "bm" ) { $size =freaddword( $f ); $reserved1 =freadword( $f ); $reserved2 =freadword( $f ); $firstbyteofimage =freaddword( $f ); $sizebitmapinfoheader =freaddword( $f ); $width =freaddword( $f ); $height =freaddword( $f ); $biplanes =freadword( $f ); $bibitcount =freadword( $f ); $rlecompression =freaddword( $f ); $widthxheight =freaddword( $f ); $bixpelspermeter =freaddword( $f ); $biypelspermeter =freaddword( $f ); $numberofpalettesused =freaddword( $f ); $numberofimportantcolors =freaddword( $f ); if ( $bibitcount <24) { $img =imagecreate( $width , $height ); $colors =pow(2, $bibitcount ); for ( $p =0; $p < $colors ; $p ++) { $b =freadbyte( $f ); $g =freadbyte( $f ); $r =freadbyte( $f ); $reserved =freadbyte( $f ); $palette []=imagecolorallocate( $img , $r , $g , $b ); }; if ( $rlecompression ==0) { $zbytek =(4- ceil (( $width /(8/ $bibitcount )))%4)%4; for ( $y = $height -1; $y >=0; $y --) { $currentbit =0; for ( $x =0; $x < $width ; $x ++) { $c =freadbits( $f , $bibitcount ); imagesetpixel( $img , $x , $y , $palette [ $c ]); }; if ( $currentbit !=0) {freadbyte( $f );}; for ( $g =0; $g < $zbytek ; $g ++) freadbyte( $f ); }; }; }; if ( $rlecompression ==1) //$bi_rle8 { $y = $height ; $pocetb =0; while (true) { $y --; $prefix =freadbyte( $f ); $suffix =freadbyte( $f ); $pocetb +=2; $echoit =false; if ( $echoit ) echo "prefix: $prefix suffix: $suffix<br>" ; if (( $prefix ==0) and ( $suffix ==1)) break ; if ( feof ( $f )) break ; while (!(( $prefix ==0) and ( $suffix ==0))) { if ( $prefix ==0) { $pocet = $suffix ; $data .= fread ( $f , $pocet ); $pocetb += $pocet ; if ( $pocetb %2==1) {freadbyte( $f ); $pocetb ++;}; }; if ( $prefix >0) { $pocet = $prefix ; for ( $r =0; $r < $pocet ; $r ++) $data .= chr ( $suffix ); }; $prefix =freadbyte( $f ); $suffix =freadbyte( $f ); $pocetb +=2; if ( $echoit ) echo "prefix: $prefix suffix: $suffix<br>" ; }; for ( $x =0; $x < strlen ( $data ); $x ++) { imagesetpixel( $img , $x , $y , $palette [ord( $data [ $x ])]); }; $data = "" ; }; }; if ( $rlecompression ==2) //$bi_rle4 { $y = $height ; $pocetb =0; /*while(!feof($f)) echo freadbyte($f)."_".freadbyte($f)."<br>";*/ while (true) { //break; $y --; $prefix =freadbyte( $f ); $suffix =freadbyte( $f ); $pocetb +=2; $echoit =false; if ( $echoit ) echo "prefix: $prefix suffix: $suffix<br>" ; if (( $prefix ==0) and ( $suffix ==1)) break ; if ( feof ( $f )) break ; while (!(( $prefix ==0) and ( $suffix ==0))) { if ( $prefix ==0) { $pocet = $suffix ; $currentbit =0; for ( $h =0; $h < $pocet ; $h ++) $data .= chr (freadbits( $f ,4)); if ( $currentbit !=0) freadbits( $f ,4); $pocetb += ceil (( $pocet /2)); if ( $pocetb %2==1) {freadbyte( $f ); $pocetb ++;}; }; if ( $prefix >0) { $pocet = $prefix ; $i =0; for ( $r =0; $r < $pocet ; $r ++) { if ( $i %2==0) { $data .= chr ( $suffix %16); } else { $data .= chr ( floor ( $suffix /16)); }; $i ++; }; }; $prefix =freadbyte( $f ); $suffix =freadbyte( $f ); $pocetb +=2; if ( $echoit ) echo "prefix: $prefix suffix: $suffix<br>" ; }; for ( $x =0; $x < strlen ( $data ); $x ++) { imagesetpixel( $img , $x , $y , $palette [ord( $data [ $x ])]); }; $data = "" ; }; }; if ( $bibitcount ==24) { $img =imagecreatetruecolor( $width , $height ); $zbytek = $width %4; for ( $y = $height -1; $y >=0; $y --) { for ( $x =0; $x < $width ; $x ++) { $b =freadbyte( $f ); $g =freadbyte( $f ); $r =freadbyte( $f ); $color =imagecolorexact( $img , $r , $g , $b ); if ( $color ==-1) $color =imagecolorallocate( $img , $r , $g , $b ); imagesetpixel( $img , $x , $y , $color ); } for ( $z =0; $z < $zbytek ; $z ++) freadbyte( $f ); }; }; return $img ; }; fclose( $f ); }; /* * helping functions: *------------------------- * * freadbyte($file) - reads 1 byte from $file * freadword($file) - reads 2 bytes (1 word) from $file * freaddword($file) - reads 4 bytes (1 dword) from $file * freadlngint($file) - same as freaddword($file) * decbin8($d) - returns binary string of d zero filled to 8 * retbits($byte,$start,$len) - returns bits $start->$start+$len from $byte * freadbits($file,$count) - reads next $count bits from $file * rgbtohex($r,$g,$b) - convert $r, $g, $b to hex * int_to_dword($n) - returns 4 byte representation of $n * int_to_word($n) - returns 2 byte representation of $n */ function freadbyte( $f ) { return ord( fread ( $f ,1)); }; function freadword( $f ) { $b1 =freadbyte( $f ); $b2 =freadbyte( $f ); return $b2 *256+ $b1 ; }; function freadlngint( $f ) { return freaddword( $f ); }; function freaddword( $f ) { $b1 =freadword( $f ); $b2 =freadword( $f ); return $b2 *65536+ $b1 ; }; function retbits( $byte , $start , $len ) { $bin =decbin8( $byte ); $r = bindec ( substr ( $bin , $start , $len )); return $r ; }; $currentbit =0; function freadbits( $f , $count ) { global $currentbit , $smode ; $byte =freadbyte( $f ); $lastcbit = $currentbit ; $currentbit += $count ; if ( $currentbit ==8) { $currentbit =0; } else { fseek ( $f , ftell ( $f )-1); }; return retbits( $byte , $lastcbit , $count ); }; function rgbtohex( $red , $green , $blue ) { $hred = dechex ( $red ); if ( strlen ( $hred )==1) $hred = "0$hred" ; $hgreen = dechex ( $green ); if ( strlen ( $hgreen )==1) $hgreen = "0$hgreen" ; $hblue = dechex ( $blue ); if ( strlen ( $hblue )==1) $hblue = "0$hblue" ; return ( $hred . $hgreen . $hblue ); }; function int_to_dword( $n ) { return chr ( $n & 255). chr (( $n >> 8) & 255). chr (( $n >> 16) & 255). chr (( $n >> 24) & 255); } function int_to_word( $n ) { return chr ( $n & 255). chr (( $n >> 8) & 255); } function decbin8( $d ) { return decbinx( $d ,8); }; function decbinx( $d , $n ) { $bin = decbin ( $d ); $sbin = strlen ( $bin ); for ( $j =0; $j < $n - $sbin ; $j ++) $bin = "0$bin" ; return $bin ; }; function inttobyte( $n ) { //开源代码phpfensi测试数据 return chr ( $n ); }; //实例方法,代码如下: include_once ( 'bmp.php' ); $image =imagecreatefrombmp( 'a.bmp' ); imagejpeg( $image , 'a.jpeg' ); imagedestroy( $image );查看更多关于php将bmp格式图片转换成jpg格式程序 - php函数的详细内容...
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