<?php

// GIF Util - (C) 2003 Yamasoft (S/C)
// http://www.yamasoft.com
// All Rights Reserved
// This file can be freely copied, distributed, modified, updated by anyone under the only
// condition to leave the original address (Yamasoft, http://www.yamasoft.com) and this header.

// <gif>  = gif_loadFile(filename, [index])
// <bool> = gif_getSize(<gif> or filename, &width, &height)
// <bool> = gif_outputAsPng(<gif>, filename, [bgColor])
// <bool> = gif_outputAsBmp(<gif>, filename, [bgcolor])
// <bool> = gif_outputAsJpeg(<gif>, filename, [bgcolor]) - Requires cjpeg

function gif_loadFile($lpszFileName, $iIndex = 0)
{
    $gif = new CGIF();

    if (!$gif->loadFile($lpszFileName, $iIndex)) {
        return false;
    }

    return $gif;
}

function gif_outputAsBmp($gif, $lpszFileName, $bgColor = -1)
{
    if (!isSet($gif) || (@get_class($gif) <> "cgif") || !$gif->loaded() || ($lpszFileName == "")) {
        return false;
    }

    $fd = $gif->getBmp($bgColor);
    if (strlen($fd) <= 0) {
        return false;
    }

    if (!($fh = @fOpen($lpszFileName, "wb"))) {
        return false;
    }
    @fWrite($fh, $fd, strlen($fd));
    @fFlush($fh);
    @fClose($fh);
    return true;
}

function gif_outputAsPng($gif, $lpszFileName, $bgColor = -1)
{
    if (!isSet($gif) || (@get_class($gif) <> "cgif") || !$gif->loaded() || ($lpszFileName == "")) {
        return false;
    }

    $fd = $gif->getPng($bgColor);
    if (strlen($fd) <= 0) {
        return false;
    }

    if (!($fh = @fOpen($lpszFileName, "wb"))) {
        return false;
    }
    @fWrite($fh, $fd, strlen($fd));
    @fFlush($fh);
    @fClose($fh);
    return true;
}

function gif_outputAsJpeg($gif, $lpszFileName, $bgColor = -1)
{
    if (gif_outputAsBmp($gif, "$lpszFileName.bmp", $gbColor)) {
        exec("cjpeg $lpszFileName.bmp >$lpszFileName 2>/dev/null");
        @unLink("$lpszFileName.bmp");

        if (@file_exists($lpszFileName)) {
            if (@fileSize($lpszFileName) > 0) {
                return true;
            }

            @unLink($lpszFileName);
        }
    }

    return false;
}

function gif_getSize($gif, &$width, &$height)
{
    if (isSet($gif) && (@get_class($gif) == "cgif") && $gif->loaded()) {
        $width = $gif->width();
        $height = $gif->height();
    } elseif (@file_exists($gif)) {
        $myGIF = new CGIF();
        if (!$myGIF->getSize($gif, $width, $height)) {
            return false;
        }
    } else {
        return false;
    }

    return true;
}

class CGIFLZW
{
    var $MAX_LZW_BITS;
    var $Fresh, $CodeSize, $SetCodeSize, $MaxCode, $MaxCodeSize, $FirstCode, $OldCode;
    var $ClearCode, $EndCode, $Next, $Vals, $Stack, $sp, $Buf, $CurBit, $LastBit, $Done, $LastByte;

    // CONSTRUCTOR
    function CGIFLZW()
    {
        $this->MAX_LZW_BITS = 12;
        unSet($this->Next);
        unSet($this->Vals);
        unSet($this->Stack);
        unSet($this->Buf);

        $this->Next = range(0, (1 << $this->MAX_LZW_BITS) - 1);
        $this->Vals = range(0, (1 << $this->MAX_LZW_BITS) - 1);
        $this->Stack = range(0, (1 << ($this->MAX_LZW_BITS + 1)) - 1);
        $this->Buf = range(0, 279);
    }

    function deCompress($data, &$datLen)
    {
        $stLen = strlen($data);
        $datLen = 0;
        $ret = "";

        // INITIALIZATION
        $this->LZWCommand($data, true);

        while (($iIndex = $this->LZWCommand($data, false)) >= 0) {
            $ret .= chr($iIndex);
        }

        $datLen = $stLen - strlen($data);

        if ($iIndex != -2) {
            return false;
        }

        return $ret;
    }

    function LZWCommand(&$data, $bInit)
    {
        if ($bInit) {
            $this->SetCodeSize = ord($data{0});
            $data = substr($data, 1);

            $this->CodeSize = $this->SetCodeSize + 1;
            $this->ClearCode = 1 << $this->SetCodeSize;
            $this->EndCode = $this->ClearCode + 1;
            $this->MaxCode = $this->ClearCode + 2;
            $this->MaxCodeSize = $this->ClearCode << 1;

            $this->GetCode($data, $bInit);

            $this->Fresh = 1;
            for ($i = 0; $i < $this->ClearCode; $i++) {
                $this->Next[$i] = 0;
                $this->Vals[$i] = $i;
            }

            for (; $i < (1 << $this->MAX_LZW_BITS); $i++) {
                $this->Next[$i] = 0;
                $this->Vals[$i] = 0;
            }

            $this->sp = 0;
            return 1;
        }

        if ($this->Fresh) {
            $this->Fresh = 0;
            do {
                $this->FirstCode = $this->GetCode($data, $bInit);
                $this->OldCode = $this->FirstCode;
            } while ($this->FirstCode == $this->ClearCode);

            return $this->FirstCode;
        }

        if ($this->sp > 0) {
            $this->sp--;
            return $this->Stack[$this->sp];
        }

        while (($Code = $this->GetCode($data, $bInit)) >= 0) {
            if ($Code == $this->ClearCode) {
                for ($i = 0; $i < $this->ClearCode; $i++) {
                    $this->Next[$i] = 0;
                    $this->Vals[$i] = $i;
                }

                for (; $i < (1 << $this->MAX_LZW_BITS); $i++) {
                    $this->Next[$i] = 0;
                    $this->Vals[$i] = 0;
                }

                $this->CodeSize = $this->SetCodeSize + 1;
                $this->MaxCodeSize = $this->ClearCode << 1;
                $this->MaxCode = $this->ClearCode + 2;
                $this->sp = 0;
                $this->FirstCode = $this->GetCode($data, $bInit);
                $this->OldCode = $this->FirstCode;

                return $this->FirstCode;
            }

            if ($Code == $this->EndCode) {
                return -2;
            }

            $InCode = $Code;
            if ($Code >= $this->MaxCode) {
                $this->Stack[$this->sp] = $this->FirstCode;
                $this->sp++;
                $Code = $this->OldCode;
            }

            while ($Code >= $this->ClearCode) {
                $this->Stack[$this->sp] = $this->Vals[$Code];
                $this->sp++;

                if ($Code == $this->Next[$Code]) // Circular table entry, big GIF Error!
                    return -1;

                $Code = $this->Next[$Code];
            }

            $this->FirstCode = $this->Vals[$Code];
            $this->Stack[$this->sp] = $this->FirstCode;
            $this->sp++;

            if (($Code = $this->MaxCode) < (1 << $this->MAX_LZW_BITS)) {
                $this->Next[$Code] = $this->OldCode;
                $this->Vals[$Code] = $this->FirstCode;
                $this->MaxCode++;

                if (($this->MaxCode >= $this->MaxCodeSize) && ($this->MaxCodeSize < (1 << $this->MAX_LZW_BITS))) {
                    $this->MaxCodeSize *= 2;
                    $this->CodeSize++;
                }
            }

            $this->OldCode = $InCode;
            if ($this->sp > 0) {
                $this->sp--;
                return $this->Stack[$this->sp];
            }
        }

        return $Code;
    }

    function GetCode(&$data, $bInit)
    {
        if ($bInit) {
            $this->CurBit = 0;
            $this->LastBit = 0;
            $this->Done = 0;
            $this->LastByte = 2;
            return 1;
        }

        if (($this->CurBit + $this->CodeSize) >= $this->LastBit) {
            if ($this->Done) {
                if ($this->CurBit >= $this->LastBit) {
                    // Ran off the end of my bits
                    return 0;
                }
                return -1;
            }

            $this->Buf[0] = $this->Buf[$this->LastByte - 2];
            $this->Buf[1] = $this->Buf[$this->LastByte - 1];

            $Count = ord($data{0});
            $data = substr($data, 1);

            if ($Count) {
                for ($i = 0; $i < $Count; $i++) {
                    $this->Buf[2 + $i] = ord($data{$i});
                }
                $data = substr($data, $Count);
            } else {
                $this->Done = 1;
            }

            $this->LastByte = 2 + $Count;
            $this->CurBit = ($this->CurBit - $this->LastBit) + 16;
            $this->LastBit = (2 + $Count) << 3;
        }

        $iRet = 0;
        for ($i = $this->CurBit, $j = 0; $j < $this->CodeSize; $i++, $j++) {
            $iRet |= (($this->Buf[intval($i / 8)] & (1 << ($i % 8))) != 0) << $j;
        }

        $this->CurBit += $this->CodeSize;
        return $iRet;
    }
}

class CGIFCOLORTABLE
{
    var $m_nColors;
    var $m_arColors;

    // CONSTRUCTOR
    function CGIFCOLORTABLE()
    {
        unSet($this->m_nColors);
        unSet($this->m_arColors);
    }

    function load($lpData, $num)
    {
        $this->m_nColors = 0;
        $this->m_arColors = array();

        for ($i = 0; $i < $num; $i++) {
            $rgb = substr($lpData, $i * 3, 3);
            if (strlen($rgb) < 3) {
                return false;
            }

            $this->m_arColors[] = (ord($rgb{2}) << 16) + (ord($rgb{1}) << 8) + ord($rgb{0});
            $this->m_nColors++;
        }

        return true;
    }

    function toString()
    {
        $ret = "";

        for ($i = 0; $i < $this->m_nColors; $i++) {
            $ret .=
                chr(($this->m_arColors[$i] & 0x000000FF)) . // R
                    chr(($this->m_arColors[$i] & 0x0000FF00) >> 8) . // G
                    chr(($this->m_arColors[$i] & 0x00FF0000) >> 16); // B
        }

        return $ret;
    }

    function toRGBQuad()
    {
        $ret = "";

        for ($i = 0; $i < $this->m_nColors; $i++) {
            $ret .=
                chr(($this->m_arColors[$i] & 0x00FF0000) >> 16) . // B
                    chr(($this->m_arColors[$i] & 0x0000FF00) >> 8) . // G
                    chr(($this->m_arColors[$i] & 0x000000FF)) . // R
                    "\x00";
        }

        return $ret;
    }

    function colorIndex($rgb)
    {
        $rgb = intval($rgb) & 0xFFFFFF;
        $r1 = ($rgb & 0x0000FF);
        $g1 = ($rgb & 0x00FF00) >> 8;
        $b1 = ($rgb & 0xFF0000) >> 16;
        $idx = -1;

        for ($i = 0; $i < $this->m_nColors; $i++) {
            $r2 = ($this->m_arColors[$i] & 0x000000FF);
            $g2 = ($this->m_arColors[$i] & 0x0000FF00) >> 8;
            $b2 = ($this->m_arColors[$i] & 0x00FF0000) >> 16;
            $d = abs($r2 - $r1) + abs($g2 - $g1) + abs($b2 - $b1);

            if (($idx == -1) || ($d < $dif)) {
                $idx = $i;
                $dif = $d;
            }
        }

        return $idx;
    }
}

class CGIFFILEHEADER
{
    var $m_lpVer;
    var $m_nWidth;
    var $m_nHeight;
    var $m_bGlobalClr;
    var $m_nColorRes;
    var $m_bSorted;
    var $m_nTableSize;
    var $m_nBgColor;
    var $m_nPixelRatio;
    var $m_colorTable;

    // CONSTRUCTOR
    function CGIFFILEHEADER()
    {
        unSet($this->m_lpVer);
        unSet($this->m_nWidth);
        unSet($this->m_nHeight);
        unSet($this->m_bGlobalClr);
        unSet($this->m_nColorRes);
        unSet($this->m_bSorted);
        unSet($this->m_nTableSize);
        unSet($this->m_nBgColor);
        unSet($this->m_nPixelRatio);
        unSet($this->m_colorTable);
    }

    function load($lpData, &$hdrLen)
    {
        $hdrLen = 0;

        $this->m_lpVer = substr($lpData, 0, 6);
        if (($this->m_lpVer <> "GIF87a") && ($this->m_lpVer <> "GIF89a")) {
            return false;
        }

        $this->m_nWidth = $this->w2i(substr($lpData, 6, 2));
        $this->m_nHeight = $this->w2i(substr($lpData, 8, 2));
        if (!$this->m_nWidth || !$this->m_nHeight) {
            return false;
        }

        $b = ord(substr($lpData, 10, 1));
        $this->m_bGlobalClr = ($b & 0x80) ? true : false;
        $this->m_nColorRes = ($b & 0x70) >> 4;
        $this->m_bSorted = ($b & 0x08) ? true : false;
        $this->m_nTableSize = 2 << ($b & 0x07);
        $this->m_nBgColor = ord(substr($lpData, 11, 1));
        $this->m_nPixelRatio = ord(substr($lpData, 12, 1));
        $hdrLen = 13;

        if ($this->m_bGlobalClr) {
            $this->m_colorTable = new CGIFCOLORTABLE();
            if (!$this->m_colorTable->load(substr($lpData, $hdrLen), $this->m_nTableSize)) {
                return false;
            }
            $hdrLen += 3 * $this->m_nTableSize;
        }

        return true;
    }

    function w2i($str)
    {
        return ord(substr($str, 0, 1)) + (ord(substr($str, 1, 1)) << 8);
    }
}

class CGIFIMAGEHEADER
{
    var $m_nLeft;
    var $m_nTop;
    var $m_nWidth;
    var $m_nHeight;
    var $m_bLocalClr;
    var $m_bInterlace;
    var $m_bSorted;
    var $m_nTableSize;
    var $m_colorTable;

    // CONSTRUCTOR
    function CGIFIMAGEHEADER()
    {
        unSet($this->m_nLeft);
        unSet($this->m_nTop);
        unSet($this->m_nWidth);
        unSet($this->m_nHeight);
        unSet($this->m_bLocalClr);
        unSet($this->m_bInterlace);
        unSet($this->m_bSorted);
        unSet($this->m_nTableSize);
        unSet($this->m_colorTable);
    }

    function load($lpData, &$hdrLen)
    {
        $hdrLen = 0;

        $this->m_nLeft = $this->w2i(substr($lpData, 0, 2));
        $this->m_nTop = $this->w2i(substr($lpData, 2, 2));
        $this->m_nWidth = $this->w2i(substr($lpData, 4, 2));
        $this->m_nHeight = $this->w2i(substr($lpData, 6, 2));

        if (!$this->m_nWidth || !$this->m_nHeight) {
            return false;
        }

        $b = ord($lpData{8});
        $this->m_bLocalClr = ($b & 0x80) ? true : false;
        $this->m_bInterlace = ($b & 0x40) ? true : false;
        $this->m_bSorted = ($b & 0x20) ? true : false;
        $this->m_nTableSize = 2 << ($b & 0x07);
        $hdrLen = 9;

        if ($this->m_bLocalClr) {
            $this->m_colorTable = new CGIFCOLORTABLE();
            if (!$this->m_colorTable->load(substr($lpData, $hdrLen), $this->m_nTableSize)) {
                return false;
            }
            $hdrLen += 3 * $this->m_nTableSize;
        }

        return true;
    }

    function w2i($str)
    {
        return ord(substr($str, 0, 1)) + (ord(substr($str, 1, 1)) << 8);
    }
}

class CGIFIMAGE
{
    var $m_disp;
    var $m_bUser;
    var $m_bTrans;
    var $m_nDelay;
    var $m_nTrans;
    var $m_lpComm;
    var $m_gih;
    var $m_data;
    var $m_lzw;

    function CGIFIMAGE()
    {
        unSet($this->m_disp);
        unSet($this->m_bUser);
        unSet($this->m_bTrans);
        unSet($this->m_nDelay);
        unSet($this->m_nTrans);
        unSet($this->m_lpComm);
        unSet($this->m_data);
        $this->m_gih = new CGIFIMAGEHEADER();
        $this->m_lzw = new CGIFLZW();
    }

    function load($data, &$datLen)
    {
        $datLen = 0;

        while (true) {
            $b = ord($data{0});
            $data = substr($data, 1);
            $datLen++;

            switch ($b) {
                case 0x21: // Extension
                    if (!$this->skipExt($data, $len = 0)) {
                        return false;
                    }
                    $datLen += $len;
                    break;

                case 0x2C: // Image
                    // LOAD HEADER & COLOR TABLE
                    if (!$this->m_gih->load($data, $len = 0)) {
                        return false;
                    }
                    $data = substr($data, $len);
                    $datLen += $len;

                    // ALLOC BUFFER
                    if (!($this->m_data = $this->m_lzw->deCompress($data, $len = 0))) {
                        return false;
                    }
                    $data = substr($data, $len);
                    $datLen += $len;

                    if ($this->m_gih->m_bInterlace) {
                        $this->deInterlace();
                    }
                    return true;

                case 0x3B: // EOF
                default:
                    return false;
            }
        }
        return false;
    }

    function skipExt(&$data, &$extLen)
    {
        $extLen = 0;

        $b = ord($data{0});
        $data = substr($data, 1);
        $extLen++;

        switch ($b) {
            case 0xF9: // Graphic Control
                $b = ord($data{1});
                $this->m_disp = ($b & 0x1C) >> 2;
                $this->m_bUser = ($b & 0x02) ? true : false;
                $this->m_bTrans = ($b & 0x01) ? true : false;
                $this->m_nDelay = $this->w2i(substr($data, 2, 2));
                $this->m_nTrans = ord($data{4});
                break;

            case 0xFE: // Comment
                $this->m_lpComm = substr($data, 1, ord($data{0}));
                break;

            case 0x01: // Plain text
                break;

            case 0xFF: // Application
                break;
        }

        // SKIP DEFAULT AS DEFS MAY CHANGE
        $b = ord($data{0});
        $data = substr($data, 1);
        $extLen++;
        while ($b > 0) {
            $data = substr($data, $b);
            $extLen += $b;
            $b = ord($data{0});
            $data = substr($data, 1);
            $extLen++;
        }
        return true;
    }

    function w2i($str)
    {
        return ord(substr($str, 0, 1)) + (ord(substr($str, 1, 1)) << 8);
    }

    function deInterlace()
    {
        $data = $this->m_data;

        for ($i = 0; $i < 4; $i++) {
            switch ($i) {
                case 0:
                    $s = 8;
                    $y = 0;
                    break;

                case 1:
                    $s = 8;
                    $y = 4;
                    break;

                case 2:
                    $s = 4;
                    $y = 2;
                    break;

                case 3:
                    $s = 2;
                    $y = 1;
                    break;
            }

            for (; $y < $this->m_gih->m_nHeight; $y += $s) {
                $lne = substr($this->m_data, 0, $this->m_gih->m_nWidth);
                $this->m_data = substr($this->m_data, $this->m_gih->m_nWidth);

                $data =
                    substr($data, 0, $y * $this->m_gih->m_nWidth) .
                        $lne .
                        substr($data, ($y + 1) * $this->m_gih->m_nWidth);
            }
        }

        $this->m_data = $data;
    }
}

class CGIF
{
    var $m_gfh;
    var $m_lpData;
    var $m_img;
    var $m_bLoaded;

    // CONSTRUCTOR
    function CGIF()
    {
        $this->m_gfh = new CGIFFILEHEADER();
        $this->m_img = new CGIFIMAGE();
        $this->m_lpData = "";
        $this->m_bLoaded = false;
    }

    function loadFile($lpszFileName, $iIndex)
    {
        if ($iIndex < 0) {
            return false;
        }

        // READ FILE
        if (!($fh = @fOpen($lpszFileName, "rb"))) {
            return false;
        }
        $data = @fRead($fh, @fileSize($lpszFileName));
        //        @fClose($fh);
        //      $data=fread($fh,filesize($lpszFileName));
        while (!feof($fh)) {
            $data = $data . @fread($fh, 1024);
            @fClose($fh);
            $this->m_lpData = @fRead($fh, @fileSize($lpszFileName));
            fClose($fh);

            // GET FILE HEADER
            if (!$this->m_gfh->load($this->m_lpData, $len = 0)) {
                return false;
            }
            $this->m_lpData = substr($this->m_lpData, $len);

            do {
                if (!$this->m_img->load($this->m_lpData, $imgLen = 0)) {
                    return false;
                }
                $this->m_lpData = substr($this->m_lpData, $imgLen);
            } while ($iIndex-- > 0);

            $this->m_bLoaded = true;
            return true;
        }

        function getSize($lpszFileName, &$width, &$height)
        {
            if (!($fh = @fOpen($lpszFileName, "rb"))) {
                return false;
            }
            $data = @fRead($fh, @fileSize($lpszFileName));
            @fClose($fh);
        }

        $gfh = new CGIFFILEHEADER();
        if (!$gfh->load($data, $len = 0)) {
            return false;
        }

        $width = $gfh->m_nWidth;
        $height = $gfh->m_nHeight;
        return true;
    }

    function getBmp($bgColor)
    {
        $out = "";

        if (!$this->m_bLoaded) {
            return false;
        }

        // PREPARE COLOR TABLE (RGBQUADs)
        if ($this->m_img->m_gih->m_bLocalClr) {
            $nColors = $this->m_img->m_gih->m_nTableSize;
            $rgbq = $this->m_img->m_gih->m_colorTable->toRGBQuad();
            if ($bgColor != -1) {
                $bgColor = $this->m_img->m_gih->m_colorTable->colorIndex($bgColor);
            }
        } elseif ($this->m_gfh->m_bGlobalClr) {
            $nColors = $this->m_gfh->m_nTableSize;
            $rgbq = $this->m_gfh->m_colorTable->toRGBQuad();
            if ($bgColor != -1) {
                $bgColor = $this->m_gfh->m_colorTable->colorIndex($bgColor);
            }
        } else {
            $nColors = 0;
            $bgColor = -1;
        }

        // PREPARE BITMAP BITS
        $data = $this->m_img->m_data;
        $nPxl = ($this->m_gfh->m_nHeight - 1) * $this->m_gfh->m_nWidth;
        $bmp = "";

        $nPad = ($this->m_gfh->m_nWidth % 4) ? 4 - ($this->m_gfh->m_nWidth % 4) : 0;
        for ($y = 0; $y < $this->m_gfh->m_nHeight; $y++) {
            for ($x = 0; $x < $this->m_gfh->m_nWidth; $x++, $nPxl++) {
                if (
                    ($x >= $this->m_img->m_gih->m_nLeft) &&
                    ($y >= $this->m_img->m_gih->m_nTop) &&
                    ($x < ($this->m_img->m_gih->m_nLeft + $this->m_img->m_gih->m_nWidth)) &&
                    ($y < ($this->m_img->m_gih->m_nTop + $this->m_img->m_gih->m_nHeight))
                ) {
                    // PART OF IMAGE
                    if ($this->m_img->m_bTrans && (ord($data{$nPxl}) == $this->m_img->m_nTrans)) {
                        // TRANSPARENT -> BACKGROUND
                        if ($bgColor == -1) {
                            $bmp .= chr($this->m_gfh->m_nBgColor);
                        } else {
                            $bmp .= chr($bgColor);
                        }
                    } else {
                        $bmp .= $data{$nPxl};
                    }
                } else {
                    // BACKGROUND
                    if ($bgColor == -1) {
                        $bmp .= chr($this->m_gfh->m_nBgColor);
                    } else {
                        $bmp .= chr($bgColor);
                    }
                }
            }
            $nPxl -= $this->m_gfh->m_nWidth << 1;

            // ADD PADDING
            for ($x = 0; $x < $nPad; $x++) {
                $bmp .= "\x00";
            }
        }

        // BITMAPFILEHEADER
        $out .= "BM";
        $out .= $this->dword(14 + 40 + ($nColors << 2) + strlen($bmp));
        $out .= "\x00\x00";
        $out .= "\x00\x00";
        $out .= $this->dword(14 + 40 + ($nColors << 2));

        // BITMAPINFOHEADER
        $out .= $this->dword(40);
        $out .= $this->dword($this->m_gfh->m_nWidth);
        $out .= $this->dword($this->m_gfh->m_nHeight);
        $out .= "\x01\x00";
        $out .= "\x08\x00";
        $out .= "\x00\x00\x00\x00";
        $out .= "\x00\x00\x00\x00";
        $out .= "\x12\x0B\x00\x00";
        $out .= "\x12\x0B\x00\x00";
        $out .= $this->dword($nColors % 256);
        $out .= "\x00\x00\x00\x00";

        // COLOR TABLE
        if ($nColors > 0) {
            $out .= $rgbq;
        }

        // DATA
        $out .= $bmp;

        return $out;
    }

    function getPng($bgColor)
    {
        $out = "";

        if (!$this->m_bLoaded) {
            return false;
        }

        // PREPARE COLOR TABLE (RGBQUADs)
        if ($this->m_img->m_gih->m_bLocalClr) {
            $nColors = $this->m_img->m_gih->m_nTableSize;
            $pal = $this->m_img->m_gih->m_colorTable->toString();
            if ($bgColor != -1) {
                $bgColor = $this->m_img->m_gih->m_colorTable->colorIndex($bgColor);
            }
        } elseif ($this->m_gfh->m_bGlobalClr) {
            $nColors = $this->m_gfh->m_nTableSize;
            $pal = $this->m_gfh->m_colorTable->toString();
            if ($bgColor != -1) {
                $bgColor = $this->m_gfh->m_colorTable->colorIndex($bgColor);
            }
        } else {
            $nColors = 0;
            $bgColor = -1;
        }

        // PREPARE BITMAP BITS
        $data = $this->m_img->m_data;
        $nPxl = 0;
        $bmp = "";
        for ($y = 0; $y < $this->m_gfh->m_nHeight; $y++) {
            $bmp .= "\x00";
            for ($x = 0; $x < $this->m_gfh->m_nWidth; $x++, $nPxl++) {
                if (
                    ($x >= $this->m_img->m_gih->m_nLeft) &&
                    ($y >= $this->m_img->m_gih->m_nTop) &&
                    ($x < ($this->m_img->m_gih->m_nLeft + $this->m_img->m_gih->m_nWidth)) &&
                    ($y < ($this->m_img->m_gih->m_nTop + $this->m_img->m_gih->m_nHeight))
                ) {
                    // PART OF IMAGE
                    $bmp .= $data{$nPxl};
                } else {
                    // BACKGROUND
                    if ($bgColor == -1) {
                        $bmp .= chr($this->m_gfh->m_nBgColor);
                    } else {
                        $bmp .= chr($bgColor);
                    }
                }
            }
        }
        $bmp = gzcompress($bmp, 9);

        // SIGNATURE
        $out .= "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A";

        // HEADER
        $out .= "\x00\x00\x00\x0D";
        $tmp = "IHDR";
        $tmp .= $this->ndword($this->m_gfh->m_nWidth);
        $tmp .= $this->ndword($this->m_gfh->m_nHeight);
        $tmp .= "\x08\x03\x00\x00\x00";
        $out .= $tmp;
        $out .= $this->ndword(crc32($tmp));

        // PALETTE
        if ($nColors > 0) {
            $out .= $this->ndword($nColors * 3);
            $tmp = "PLTE";
            $tmp .= $pal;
            $out .= $tmp;
            $out .= $this->ndword(crc32($tmp));
        }

        // TRANSPARENCY
        if ($this->m_img->m_bTrans && ($nColors > 0)) {
            $out .= $this->ndword($nColors);
            $tmp = "tRNS";
            for ($i = 0; $i < $nColors; $i++) {
                $tmp .= ($i == $this->m_img->m_nTrans) ? "\x00" : "\xFF";
            }
            $out .= $tmp;
            $out .= $this->ndword(crc32($tmp));
        }

        // DATA BITS
        $out .= $this->ndword(strlen($bmp));
        $tmp = "IDAT";
        $tmp .= $bmp;
        $out .= $tmp;
        $out .= $this->ndword(crc32($tmp));

        // END OF FILE
        $out .= "\x00\x00\x00\x00IEND\xAE\x42\x60\x82";

        return $out;
    }

    function dword($val)
    {
        $val = intval($val);
        return chr($val & 0xFF) . chr(($val & 0xFF00) >> 8) . chr(($val & 0xFF0000) >> 16) . chr(($val & 0xFF000000) >> 24);
    }

    function ndword($val)
    {
        $val = intval($val);
        return chr(($val & 0xFF000000) >> 24) . chr(($val & 0xFF0000) >> 16) . chr(($val & 0xFF00) >> 8) . chr($val & 0xFF);
    }

    function width()
    {
        return $this->m_gfh->m_nWidth;
    }

    function height()
    {
        return $this->m_gfh->m_nHeight;
    }

    function comment()
    {
        return $this->m_img->m_lpComm;
    }

    function loaded()
    {
        return $this->m_bLoaded;
    }
}

// Local Variables:
// mode: php
// tab-width: 8
// c-basic-offset: 4
// c-hanging-comment-ender-p: nil
// indent-tabs-mode: nil
// End:
