PHP program to convert bmp format pictures into jpg format_PHP tutorial

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  {
   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: $suffix
";
if(($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
";
};

for($x=0;$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)."
";*/
while(true)
{
//break;
$y--;
$prefix=freadbyte($f);
$suffix=freadbyte($f);
$pocetb+=2;

$echoit=false;

if($echoit)echo "prefix: $prefix suffix: $suffix
";
if(($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
";
};

for($x=0;$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);

 

http://www.bkjia.com/PHPjc/444910.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/444910.htmlTechArticlephp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); $istranspa...