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PHP uses the GIFEncoder class to process gif image instances_PHP tutorial
PHP uses the GIFEncoder class to process gif image instances_PHP tutorial
Jul 13, 2016 am 10:26 AM
The source code of the processing is posted below:
require_once("gifencoder.php"); //Load encoding file
$gif = new GIFEncoder(); //Instantiate the gif decoding object
$gif->load("test.gif"); //Load the gif image to be decoded
for($i=0;$i
$im = imagecreatefromstring($gif->getgif($i)); //Use GD library function to convert GIF to a standard
imagegif($im, $i.".gif"); //Save each frame of image data generated in file form, of course you can also use variables
}
imagedestroy($im);
ob_start();
for($i=0;sizeof($gif->IMGS["frames"]);$i++){
$im=imagecreatefromgif("0.gif"); //Create an image based on the picture of each frame
if($i>0){ ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? $ Frame = ImagecreateFromgif ("$ i.gif"); // Read the image of the current frame
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? $y= imagesy($frame); Imagecopy($im,$frame,0,0,0,0,$w,$y); //Copy and merge the current frame image and the first frame image
imagedestroy($frame); //Destroy the current image
}
imagejpeg($im,$i."frame.jpg"); //Save in jpg format after merging
$im=imagecreatefromjpeg($i."frame.jpg"); //Recreate image from jpg format
imagegif($im); ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? imagedestroy($im); ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? $imagedata[] = ob_get_contents(); //Create the image data of this frame
Ob_clean();
}
$diy[]=0;//Start delay time
$gif = new GIFEncoder($imagedata,$diy,0,2,0,0,0,"bin"); //Instantiate the gif encoding object
ob_start();
Header ('Content-type:image/gif');
echo $gif->GetAnimation();
?>
The above code is basically a complete process of reading a gif image, decoding it, and then encoding it into a gif image..
With this, you can grab gif images from the Internet and modify them. You can even create some gif images directly using php.
The code is as follows:
?
Class GIFEncoder {
??? var $GIF = "GIF89a";??????????????? /* GIF header 6 bytes??????? */
??? var $VER = "GIFEncoder V2.06";??????? /* Encoder version??????????????? */
??? var $BUF = Array ( );
??? var $LOP =? 0;
??? var $DIS =? 2;
??? var $COL = -1;
??? var $IMG = -1;
??? var $ERR = Array (
??? 'ERR00' =>"Does not supported function for only one image!",
??? 'ERR01' =>"Source is not a GIF image!",
??? 'ERR02' =>"Unintelligible flag ",
??? 'ERR03' =>"Could not make animation from animated GIF source",
??? );
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GIFEncoder...
??? ::
??? */
??? function GIFEncoder??????? (
??? $GIF_src, $GIF_dly, $GIF_lop, $GIF_dis,
??? $GIF_red, $GIF_grn, $GIF_blu, $GIF_mod
??? ) {
??????? if ( ! is_array ( $GIF_src ) && ! is_array ( $GIF_tim ) ) {
??????????? printf??????? ( "%s: %s", $this->VER, $this->ERR [ 'ERR00' ] );
??????????? exit??????? ( 0 );
??????? }
??????? $this->LOP = ( $GIF_lop > -1 ) ? $GIF_lop : 0;
??????? $this->DIS = ( $GIF_dis > -1 ) ? ( ( $GIF_dis < 3 ) ? $GIF_dis : 3 ) : 2;
??????? $this->COL = ( $GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1 ) ?
??????? ( $GIF_red | ( $GIF_grn << 8 ) | ( $GIF_blu << 16 ) ) : -1;
??????? for ( $i = 0; $i < count ( $GIF_src ); $i++ ) {
??????????? if ( strToLower ( $GIF_mod ) == "url" ) {
??????????????? $this->BUF [ ] = fread ( fopen ( $GIF_src [ $i ], "rb" ), filesize ( $GIF_src [ $i ] ) );
??????????? }
??????????? else if ( strToLower ( $GIF_mod ) == "bin" ) {
??????????????? $this->BUF [ ] = $GIF_src [ $i ];
??????????? }
??????????? else {
??????????????? printf??????? ( "%s: %s ( %s )!", $this->VER, $this->ERR [ 'ERR02' ], $GIF_mod );
??????????????? exit??????? ( 0 );
??????????? }
??????????? if ( substr ( $this->BUF [ $i ], 0, 6 ) != "GIF87a" && substr ( $this->BUF [ $i ], 0, 6 ) != "GIF89a" ) {
??????????????? printf??????? ( "%s: %d %s", $this->VER, $i, $this->ERR [ 'ERR01' ] );
??????????????? exit??????? ( 0 );
??????????? }
??????????? for ( $j = ( 13 + 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ) ), $k = TRUE; $k; $j++ ) {
??????????????? switch ( $this->BUF [ $i ] { $j } ) {
??????????????????? case "!":
??????????????????????? if ( ( substr ( $this->BUF [ $i ], ( $j + 3 ), 8 ) ) == "NETSCAPE" ) {
??????????????????????????? printf??????? ( "%s: %s ( %s source )!", $this->VER, $this->ERR [ 'ERR03' ], ( $i + 1 ) );
??????????????????????????? exit??????? ( 0 );
??????????????????????? }
??????????????????????? break;
??????????????????? case ";":
??????????????????????? $k = FALSE;
??????????????????????? break;
??????????????? }
??????????? }
??????? }
??????? GIFEncoder::GIFAddHeader ( );
??????? for ( $i = 0; $i < count ( $this->BUF ); $i++ ) {
??????????? GIFEncoder::GIFAddFrames ( $i, $GIF_dly [ $i ] );
??????? }
??????? GIFEncoder::GIFAddFooter ( );
??? }
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GIFAddHeader...
??? ::
??? */
??? function GIFAddHeader ( ) {
??????? $cmap = 0;
??????? if ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x80 ) {
??????????? $cmap = 3 * ( 2 << ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 ) );
??????????? $this->GIF .= substr ( $this->BUF [ 0 ], 6, 7??????????????? );
??????????? $this->GIF .= substr ( $this->BUF [ 0 ], 13, $cmap??????? );
??????????? $this->GIF .= "!/377/13NETSCAPE2.0/3/1" . GIFEncoder::GIFWord ( $this->LOP ) . "/0";
??????? }
??? }
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GIFAddFrames...
??? ::
??? */
??? function GIFAddFrames ( $i, $d ) {
??????? $Locals_str = 13 + 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) );
??????? $Locals_end = strlen ( $this->BUF [ $i ] ) - $Locals_str - 1;
??????? $Locals_tmp = substr ( $this->BUF [ $i ], $Locals_str, $Locals_end );
??????? $Global_len = 2 << ( ord ( $this->BUF [ 0? ] { 10 } ) & 0x07 );
??????? $Locals_len = 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 );
??????? $Global_rgb = substr ( $this->BUF [ 0? ], 13,
??????? 3 * ( 2 << ( ord ( $this->BUF [ 0? ] { 10 } ) & 0x07 ) ) );
??????? $Locals_rgb = substr ( $this->BUF [ $i ], 13,
??????? 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ) );
??????? $Locals_ext = "!/xF9/x04" . chr ( ( $this->DIS << 2 ) + 0 ) .
??????? chr ( ( $d >> 0 ) & 0xFF ) . chr ( ( $d >> 8 ) & 0xFF ) . "/x0/x0";
??????? if ( $this->COL > -1 && ord ( $this->BUF [ $i ] { 10 } ) & 0x80 ) {
??????????? for ( $j = 0; $j < ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ); $j++ ) {
??????????????? 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
??????????????? ) {
??????????????????? $Locals_ext = "!/xF9/x04" . chr ( ( $this->DIS << 2 ) + 1 ) .
??????????????????? chr ( ( $d >> 0 ) & 0xFF ) . chr ( ( $d >> 8 ) & 0xFF ) . chr ( $j ) . "/x0";
??????????????????? break;
??????????????? }
??????????? }
??????? }
??????? switch ( $Locals_tmp { 0 } ) {
??????????? case "!":
??????????????? $Locals_img = substr ( $Locals_tmp, 8, 10 );
??????????????? $Locals_tmp = substr ( $Locals_tmp, 18, strlen ( $Locals_tmp ) - 18 );
??????????????? break;
??????????? case ",":
??????????????? $Locals_img = substr ( $Locals_tmp, 0, 10 );
??????????????? $Locals_tmp = substr ( $Locals_tmp, 10, strlen ( $Locals_tmp ) - 10 );
??????????????? break;
??????? }
??????? if ( ord ( $this->BUF [ $i ] { 10 } ) & 0x80 && $this->IMG > -1 ) {
??????????? if ( $Global_len == $Locals_len ) {
??????????????? if ( GIFEncoder::GIFBlockCompare ( $Global_rgb, $Locals_rgb, $Global_len ) ) {
??????????????????? $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );
??????????????? }
??????????????? else {
??????????????????? $byte? = ord ( $Locals_img { 9 } );
??????????????????? $byte |= 0x80;
??????????????????? $byte &= 0xF8;
??????????????????? $byte |= ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 );
??????????????????? $Locals_img { 9 } = chr ( $byte );
??????????????????? $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );
??????????????? }
??????????? }
??????????? else {
??????????????? $byte? = ord ( $Locals_img { 9 } );
??????????????? $byte |= 0x80;
??????????????? $byte &= 0xF8;
??????????????? $byte |= ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 );
??????????????? $Locals_img { 9 } = chr ( $byte );
??????????????? $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );
??????????? }
??????? }
??????? else {
??????????? $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );
??????? }
??????? $this->IMG? = 1;
??? }
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GIFAddFooter...
??? ::
??? */
??? function GIFAddFooter ( ) {
??????? $this->GIF .= ";";
??? }
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GIFBlockCompare...
??? ::
??? */
??? function GIFBlockCompare ( $GlobalBlock, $LocalBlock, $Len ) {
??????? for ( $i = 0; $i < $Len; $i++ ) {
??????????? 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 }
??????????? ) {
??????????????? return ( 0 );
??????????? }
??????? }
??????? return ( 1 );
??? }
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GIFWord...
??? ::
??? */
??? function GIFWord ( $int ) {
??????? return ( chr ( $int & 0xFF ) . chr ( ( $int >> 8 ) & 0xFF ) );
??? }
??? /*
??? :::::::::::::::::::::::::::::::::::::::::::::::::::
??? ::
??? ::??????? GetAnimation...
??? ::
??? */
??? function GetAnimation ( ) {
??????? return ( $this->GIF );
??? }
}
?>
?
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