php bmp格式图片转换成jpg格式程序

2022-03-02 19:08:12 浏览数 (1)

代码语言:javascript复制
<?php
/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
*/
//php教程将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);
                            }
                            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) {
    return chr($n);
};

//实例方法
//include_once('bmp.php');
$image=imagecreatefrombmp('a.bmp');
imagejpeg($image,'a.jpeg');
imagedestroy($image);

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