File size: 8.77Kb
<?php
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFDecoder Version 2.0 by László Zsidi
::
:: Created at 2007. 02. 01. '07.47.AM'
::
:: Updated at 2009. 06. 23. '06.00.AM'
::
:: * Optimized version by xurei
:: https://github.com/xurei/GIFDecoder_optimized
:: Updated at 2015-04-13
::
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
*/
class GIF_Decoder
{
var $GIF_TransparentR = -1;
var $GIF_TransparentG = -1;
var $GIF_TransparentB = -1;
var $GIF_TransparentI = 0;
var $GIF_buffer = null;
var $GIF_arrays = Array();
var $GIF_delays = Array();
var $GIF_dispos = Array();
var $GIF_stream = "";
var $GIF_string = "";
var $GIF_bfseek = 0;
var $GIF_anloop = 0;
//xurei - frames metadata
var $GIF_frames_meta = Array();
var $GIF_screen = Array();
var $GIF_global = Array(); //global color map
var $GIF_sorted;
var $GIF_colorS; //
var $GIF_colorC; //Size of global color table
var $GIF_colorF; //if 1, global color table follows image descriptor
/*
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::
:: GIFDecoder ( $GIF_pointer )
::
*/
function __construct($GIF_pointer)
{
$this->GIF_stream = $GIF_pointer;
GIF_Decoder::GIFGetByte(6);
GIF_Decoder::GIFGetByte(7);
$this->GIF_screen = $this->GIF_buffer;
$this->GIF_colorF = $this->GIF_buffer [4] & 0x80 ? 1 : 0;
$this->GIF_sorted = $this->GIF_buffer [4] & 0x08 ? 1 : 0;
$this->GIF_colorC = $this->GIF_buffer [4] & 0x07;
$this->GIF_colorS = 2 << $this->GIF_colorC;
if ($this->GIF_colorF == 1) {
GIF_Decoder::GIFGetByte(3 * $this->GIF_colorS);
$this->GIF_global = $this->GIF_buffer;
}
for ($cycle = 1; $cycle;) {
if (GIF_Decoder::GIFGetByte(1)) {
switch ($this->GIF_buffer [0]) {
case 0x21:
GIF_Decoder::GIFReadExtensions();
break;
case 0x2C:
GIF_Decoder::GIFReadDescriptor();
break;
case 0x3B:
$cycle = 0;
break;
}
} else {
$cycle = 0;
}
}
}
/*
:::::::::::::::::::::::::::::::::::::::::::::::::::
::
:: GIFReadExtension ( )
::
*/
function GIFReadExtensions()
{
GIF_Decoder::GIFGetByte(1);
if ($this->GIF_buffer [0] == 0xff) {
for (;;) {
GIF_Decoder::GIFGetByte(1);
if (( $u = $this->GIF_buffer [0] ) == 0x00) {
break;
}
GIF_Decoder::GIFGetByte($u);
if ($u == 0x03) {
$this->GIF_anloop = ( $this->GIF_buffer [1] | $this->GIF_buffer [2] << 8 );
}
}
} else {
for (;;) {
GIF_Decoder::GIFGetByte(1);
if (( $u = $this->GIF_buffer [0] ) == 0x00) {
break;
}
GIF_Decoder::GIFGetByte($u);
if ($u == 0x04) {
$buf4 = count($this->GIF_buffer) >= 5 ? $this->GIF_buffer [4] : 0;
if ($buf4 & 0x80) {
$this->GIF_dispos [] = ( $this->GIF_buffer [0] >> 2 ) - 1;
} else {
$this->GIF_dispos [] = ( $this->GIF_buffer [0] >> 2 ) - 0;
}
$this->GIF_delays [] = ( $this->GIF_buffer [1] | $this->GIF_buffer [2] << 8 );
if ($this->GIF_buffer [3]) {
$this->GIF_TransparentI = $this->GIF_buffer [3];
}
}
}
}
}
/*
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::
:: GIFReadDescriptor ( )
::
*/
function GIFReadDescriptor()
{
$GIF_screen = Array();
GIF_Decoder::GIFGetByte(9);
//xurei - metadata saving
$this->GIF_frames_meta[] = array(
'left' => $this->GIF_buffer[0] + ($this->GIF_buffer[1] << 8),
'top' => $this->GIF_buffer[2] + ($this->GIF_buffer[3] << 8),
'width' => $this->GIF_buffer[4] + ($this->GIF_buffer[5] << 8),
'height' => $this->GIF_buffer[6] + ($this->GIF_buffer[7] << 8),
);
$GIF_screen = $this->GIF_buffer;
$GIF_colorF = $this->GIF_buffer [8] & 0x80 ? 1 : 0;
if ($GIF_colorF) {
$GIF_code = $this->GIF_buffer [8] & 0x07;
$GIF_sort = $this->GIF_buffer [8] & 0x20 ? 1 : 0;
} else {
$GIF_code = $this->GIF_colorC;
$GIF_sort = $this->GIF_sorted;
}
$GIF_size = 2 << $GIF_code;
$this->GIF_screen [4] &= 0x70;
$this->GIF_screen [4] |= 0x80;
$this->GIF_screen [4] |= $GIF_code;
if ($GIF_sort) {
$this->GIF_screen [4] |= 0x08;
}
/*
*
* GIF Data Begin
*
*/
if ($this->GIF_TransparentI) {
$this->GIF_string = "GIF89a";
} else {
$this->GIF_string = "GIF87a";
}
GIF_Decoder::GIFPutByte($this->GIF_screen);
if ($GIF_colorF == 1) {
GIF_Decoder::GIFGetByte(3 * $GIF_size);
if ($this->GIF_TransparentI) {
$this->GIF_TransparentR = $this->GIF_buffer [3 * $this->GIF_TransparentI + 0];
$this->GIF_TransparentG = $this->GIF_buffer [3 * $this->GIF_TransparentI + 1];
$this->GIF_TransparentB = $this->GIF_buffer [3 * $this->GIF_TransparentI + 2];
}
GIF_Decoder::GIFPutByte($this->GIF_buffer);
} else {
if ($this->GIF_TransparentI) {
$this->GIF_TransparentR = $this->GIF_global [3 * $this->GIF_TransparentI + 0];
$this->GIF_TransparentG = $this->GIF_global [3 * $this->GIF_TransparentI + 1];
$this->GIF_TransparentB = $this->GIF_global [3 * $this->GIF_TransparentI + 2];
}
GIF_Decoder::GIFPutByte($this->GIF_global);
}
if ($this->GIF_TransparentI) {
$this->GIF_string .= "!\xF9\x04\x1\x0\x0" . chr($this->GIF_TransparentI) . "\x0";
}
$this->GIF_string .= chr(0x2C);
$GIF_screen [8] &= 0x40;
GIF_Decoder::GIFPutByte($GIF_screen);
GIF_Decoder::GIFGetByte(1);
GIF_Decoder::GIFPutByte($this->GIF_buffer);
for (;;) {
GIF_Decoder::GIFGetByte(1);
GIF_Decoder::GIFPutByte($this->GIF_buffer);
if (( $u = $this->GIF_buffer [0] ) == 0x00) {
break;
}
/* for ($i=0; $i!=$u; ++$i)
{
$this->GIF_string .= $this->GIF_stream { $this->GIF_bfseek++ };
} */
$this->GIF_string .= substr($this->GIF_stream, $this->GIF_bfseek, $u);
$this->GIF_bfseek += $u;
//GIF_Decoder::GIFGetByte ( $u );
//GIF_Decoder::GIFPutByte ( $this->GIF_buffer );
}
$this->GIF_string .= chr(0x3B);
/*
*
* GIF Data End
*
*/
$this->GIF_arrays [] = $this->GIF_string;
}
/*
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::
:: GIFGetByte ( $len )
::
*/
function GIFGetByte($len)
{
$this->GIF_buffer = new SplFixedArray($len);
$l = strlen($this->GIF_stream);
for ($i = 0; $i < $len; $i++) {
if ($this->GIF_bfseek > $l) {
$this->GIF_buffer->setSize($i);
return 0;
}
$this->GIF_buffer [$i] = ord($this->GIF_stream [ $this->GIF_bfseek++]);
}
return 1;
}
/*
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::
:: GIFPutByte ( $bytes )
::
*/
function GIFPutByte($bytes)
{
$out = '';
foreach ($bytes as $byte) {
$out .= chr($byte);
}
$this->GIF_string .= $out;
}
/*
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::
:: PUBLIC FUNCTIONS
::
::
:: GIFGetFrames ( )
::
*/
function GIFGetFrames()
{
return ( $this->GIF_arrays );
}
/*
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::
:: GIFGetFramesMeta ( )
::
:: xurei - returns metadata as an array of arrays
*/
function GIFGetFramesMeta()
{
return ( $this->GIF_frames_meta );
}
/*
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::
:: GIFGetDelays ( )
::
*/
function GIFGetDelays()
{
return ( $this->GIF_delays );
}
/*
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::
:: GIFGetLoop ( )
::
*/
function GIFGetLoop()
{
return ( $this->GIF_anloop );
}
/*
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::
:: GIFGetDisposal ( )
::
*/
function GIFGetDisposal()
{
return ( $this->GIF_dispos );
}
/*
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::
:: GIFGetTransparentR ( )
::
*/
function GIFGetTransparentR()
{
return ( $this->GIF_TransparentR );
}
/*
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::
:: GIFGetTransparentG ( )
::
*/
function GIFGetTransparentG()
{
return ( $this->GIF_TransparentG );
}
/*
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::
:: GIFGetTransparentB ( )
::
*/
function GIFGetTransparentB()
{
return ( $this->GIF_TransparentB );
}
/*
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::
:: GIFGetTransparentI ( )
::
*/
function GIFGetTransparentI()
{
return ( $this->GIF_TransparentI );
}
}