php 将bmp格式的图片转换成任意格式
$path = 'images/bmp.' ;
$pathAll = $path.'bmp' ;
$mi = '' ;
$mi = ImageCreateFromBMP1( $pathAll );
imagejpeg($mi, $path.'jpg');
imagegif($mi, $path.'gif');
// 函数如下：
function ImageCreateFromBMP1( $filename ) {
// Ouverture du fichier en mode binaire
if (!$f1 = fopen ( $filename , "rb" )) return FALSE ;
// 1 : Chargement des FICHIER
$FILE = unpack ( "vfile_type/Vfile_size/Vreserved/Vbitmap_offset" , fread ( $f1 , 14 ));
if ($FILE ['file_type'] != 19778 ) return FALSE ;
// 2 : Chargement des BMP
$BMP = unpack ('Vheader_size/Vwidth/Vheight/vplanes/vbits_per_pixel'.
'/Vcompression/Vsize_bitmap/Vhoriz_resolution'.
'/Vvert_resolution/Vcolors_used/Vcolors_important', fread ( $f1 , 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 ;
// 3 : Chargement des couleurs de la palette
$PALETTE = array ();
if ( $BMP ['colors'] < 16777216 ) {
$PALETTE = unpack ('V' . $BMP ['colors'] , fread ( $f1 , $BMP ['colors'] * 4 ));
}
// 4 : 'image
$IMG = fread ( $f1 , $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 < $BMP ['width']) {
if ($BMP ['bits_per_pixel'] == 24) {
$COLOR = unpack ("V" , substr ($IMG , $P , 3) . $VIDE );
}elseif ( $BMP ['bits_per_pixel'] == 16 ){
$COLOR = unpack ("n" , substr ( $IMG , $P , 2 ));
$COLOR [ 1 ] = $PALETTE [ $COLOR [ 1 ] + 1 ];
} elseif ( $BMP ['bits_per_pixel'] == 8 ) {
$COLOR = unpack ("n", $VIDE . substr ( $IMG , $P , 1 ));
$COLOR [ 1 ] = $PALETTE [ $COLOR [ 1 ] + 1 ];
} elseif ( $BMP ['bits_per_pixel'] == 4 ) {
$COLOR = unpack ("n", $VIDE . substr ( $IMG , 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 ];
} elseif ( $BMP ['bits_per_pixel'] == 1 ) {
$COLOR = unpack ("n", $VIDE . substr ( $IMG , floor ( $P ) , 1 ));
if (( $P * 8 ) % 8 == 0 ) $COLOR [ 1 ] = $COLOR [ 1 ] >> 7 ;
elseif (( $P * 8 ) % 8 == 1 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x40 ) >> 6 ;
elseif (( $P * 8 ) % 8 == 2 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x20 ) >> 5 ;
elseif (( $P * 8 ) % 8 == 3 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x10 ) >> 4 ;
elseif (( $P * 8 ) % 8 == 4 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x8 ) >> 3 ;
elseif (( $P * 8 ) % 8 == 5 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x4 ) >> 2 ;
elseif (( $P * 8 ) % 8 == 6 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x2 ) >> 1 ;
elseif (( $P * 8 ) % 8 == 7 ) $COLOR [ 1 ] = ( $COLOR [ 1 ] & 0x1 );
$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'];
}
// Fermeture du fichier
fclose ( $f1 );
return $res ;
}
