/common/libraries/plugin/getid3/module.graphic.bmp.php

<?php

/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at http://getid3.sourceforge.net                 //
//            or http://www.getid3.org                         //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details                             //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.graphic.bmp.php                                      //
// module for analyzing BMP Image files                        //
// dependencies: NONE                                          //
//                                                            ///
/////////////////////////////////////////////////////////////////




class getid3_bmp

{



    function __construct(&$fd, &$ThisFileInfo, $ExtractPalette = false, $ExtractData = false)

    {

        

        // shortcuts
        $ThisFileInfo['bmp']['header']['raw'] = array();

        $thisfile_bmp = &$ThisFileInfo['bmp'];

        $thisfile_bmp_header = &$thisfile_bmp['header'];

        $thisfile_bmp_header_raw = &$thisfile_bmp_header['raw'];

        

        // BITMAPFILEHEADER [14 bytes] - http://msdn.microsoft.com/library/en-us/gdi/bitmaps_62uq.asp
        // all versions
        // WORD    bfType;
        // DWORD   bfSize;
        // WORD    bfReserved1;
        // WORD    bfReserved2;
        // DWORD   bfOffBits;
        



        fseek($fd, $ThisFileInfo['avdataoffset'], SEEK_SET);

        $offset = 0;

        $BMPheader = fread($fd, 14 + 40);

        

        $thisfile_bmp_header_raw['identifier'] = substr($BMPheader, $offset, 2);

        $offset += 2;

        

        if ($thisfile_bmp_header_raw['identifier'] != 'BM')

        {

            $ThisFileInfo['error'][] = 'Expecting "BM" at offset ' . $ThisFileInfo['avdataoffset'] . ', found "' . $thisfile_bmp_header_raw['identifier'] . '"';

            unset($ThisFileInfo['fileformat']);

            unset($ThisFileInfo['bmp']);

            return false;

        }

        

        $thisfile_bmp_header_raw['filesize'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

        $offset += 4;

        $thisfile_bmp_header_raw['reserved1'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

        $offset += 2;

        $thisfile_bmp_header_raw['reserved2'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

        $offset += 2;

        $thisfile_bmp_header_raw['data_offset'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

        $offset += 4;

        $thisfile_bmp_header_raw['header_size'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

        $offset += 4;

        

        // check if the hardcoded-to-1 "planes" is at offset 22 or 26
        $planes22 = getid3_lib :: LittleEndian2Int(substr($BMPheader, 22, 2));

        $planes26 = getid3_lib :: LittleEndian2Int(substr($BMPheader, 26, 2));

        if (($planes22 == 1) && ($planes26 != 1))

        {

            $thisfile_bmp['type_os'] = 'OS/2';

            $thisfile_bmp['type_version'] = 1;

        }

        elseif (($planes26 == 1) && ($planes22 != 1))

        {

            $thisfile_bmp['type_os'] = 'Windows';

            $thisfile_bmp['type_version'] = 1;

        }

        elseif ($thisfile_bmp_header_raw['header_size'] == 12)

        {

            $thisfile_bmp['type_os'] = 'OS/2';

            $thisfile_bmp['type_version'] = 1;

        }

        elseif ($thisfile_bmp_header_raw['header_size'] == 40)

        {

            $thisfile_bmp['type_os'] = 'Windows';

            $thisfile_bmp['type_version'] = 1;

        }

        elseif ($thisfile_bmp_header_raw['header_size'] == 84)

        {

            $thisfile_bmp['type_os'] = 'Windows';

            $thisfile_bmp['type_version'] = 4;

        }

        elseif ($thisfile_bmp_header_raw['header_size'] == 100)

        {

            $thisfile_bmp['type_os'] = 'Windows';

            $thisfile_bmp['type_version'] = 5;

        }

        else

        {

            $ThisFileInfo['error'][] = 'Unknown BMP subtype (or not a BMP file)';

            unset($ThisFileInfo['fileformat']);

            unset($ThisFileInfo['bmp']);

            return false;

        }

        

        $ThisFileInfo['fileformat'] = 'bmp';

        $ThisFileInfo['video']['dataformat'] = 'bmp';

        $ThisFileInfo['video']['lossless'] = true;

        $ThisFileInfo['video']['pixel_aspect_ratio'] = (float) 1;

        

        if ($thisfile_bmp['type_os'] == 'OS/2')

        {

            

            // OS/2-format BMP
            // http://netghost.narod.ru/gff/graphics/summary/os2bmp.htm
            



            // DWORD  Size;             /* Size of this structure in bytes */
            // DWORD  Width;            /* Bitmap width in pixels */
            // DWORD  Height;           /* Bitmap height in pixel */
            // WORD   NumPlanes;        /* Number of bit planes (color depth) */
            // WORD   BitsPerPixel;     /* Number of bits per pixel per plane */
            



            $thisfile_bmp_header_raw['width'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

            $offset += 2;

            $thisfile_bmp_header_raw['height'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

            $offset += 2;

            $thisfile_bmp_header_raw['planes'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

            $offset += 2;

            $thisfile_bmp_header_raw['bits_per_pixel'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

            $offset += 2;

            

            $ThisFileInfo['video']['resolution_x'] = $thisfile_bmp_header_raw['width'];

            $ThisFileInfo['video']['resolution_y'] = $thisfile_bmp_header_raw['height'];

            $ThisFileInfo['video']['codec'] = 'BI_RGB ' . $thisfile_bmp_header_raw['bits_per_pixel'] . '-bit';

            $ThisFileInfo['video']['bits_per_sample'] = $thisfile_bmp_header_raw['bits_per_pixel'];

            

            if ($thisfile_bmp['type_version'] >= 2)

            {

                // DWORD  Compression;      /* Bitmap compression scheme */
                // DWORD  ImageDataSize;    /* Size of bitmap data in bytes */
                // DWORD  XResolution;      /* X resolution of display device */
                // DWORD  YResolution;      /* Y resolution of display device */
                // DWORD  ColorsUsed;       /* Number of color table indices used */
                // DWORD  ColorsImportant;  /* Number of important color indices */
                // WORD   Units;            /* Type of units used to measure resolution */
                // WORD   Reserved;         /* Pad structure to 4-byte boundary */
                // WORD   Recording;        /* Recording algorithm */
                // WORD   Rendering;        /* Halftoning algorithm used */
                // DWORD  Size1;            /* Reserved for halftoning algorithm use */
                // DWORD  Size2;            /* Reserved for halftoning algorithm use */
                // DWORD  ColorEncoding;    /* Color model used in bitmap */
                // DWORD  Identifier;       /* Reserved for application use */
                



                $thisfile_bmp_header_raw['compression'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['bmp_data_size'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['resolution_h'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['resolution_v'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['colors_used'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['colors_important'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['resolution_units'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

                $offset += 2;

                $thisfile_bmp_header_raw['reserved1'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

                $offset += 2;

                $thisfile_bmp_header_raw['recording'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

                $offset += 2;

                $thisfile_bmp_header_raw['rendering'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

                $offset += 2;

                $thisfile_bmp_header_raw['size1'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['size2'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['color_encoding'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['identifier'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                

                $thisfile_bmp_header['compression'] = $this->BMPcompressionOS2Lookup($thisfile_bmp_header_raw['compression']);

                

                $ThisFileInfo['video']['codec'] = $thisfile_bmp_header['compression'] . ' ' . $thisfile_bmp_header_raw['bits_per_pixel'] . '-bit';

            }

        

        }

        elseif ($thisfile_bmp['type_os'] == 'Windows')

        {

            

            // Windows-format BMP
            



            // BITMAPINFOHEADER - [40 bytes] http://msdn.microsoft.com/library/en-us/gdi/bitmaps_1rw2.asp
            // all versions
            // DWORD  biSize;
            // LONG   biWidth;
            // LONG   biHeight;
            // WORD   biPlanes;
            // WORD   biBitCount;
            // DWORD  biCompression;
            // DWORD  biSizeImage;
            // LONG   biXPelsPerMeter;
            // LONG   biYPelsPerMeter;
            // DWORD  biClrUsed;
            // DWORD  biClrImportant;
            



            // possibly integrate this section and module.audio-video.riff.php::ParseBITMAPINFOHEADER() ?
            



            $thisfile_bmp_header_raw['width'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4), true);

            $offset += 4;

            $thisfile_bmp_header_raw['height'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4), true);

            $offset += 4;

            $thisfile_bmp_header_raw['planes'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

            $offset += 2;

            $thisfile_bmp_header_raw['bits_per_pixel'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 2));

            $offset += 2;

            $thisfile_bmp_header_raw['compression'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

            $offset += 4;

            $thisfile_bmp_header_raw['bmp_data_size'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

            $offset += 4;

            $thisfile_bmp_header_raw['resolution_h'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4), true);

            $offset += 4;

            $thisfile_bmp_header_raw['resolution_v'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4), true);

            $offset += 4;

            $thisfile_bmp_header_raw['colors_used'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

            $offset += 4;

            $thisfile_bmp_header_raw['colors_important'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

            $offset += 4;

            

            $thisfile_bmp_header['compression'] = $this->BMPcompressionWindowsLookup($thisfile_bmp_header_raw['compression']);

            $ThisFileInfo['video']['resolution_x'] = $thisfile_bmp_header_raw['width'];

            $ThisFileInfo['video']['resolution_y'] = $thisfile_bmp_header_raw['height'];

            $ThisFileInfo['video']['codec'] = $thisfile_bmp_header['compression'] . ' ' . $thisfile_bmp_header_raw['bits_per_pixel'] . '-bit';

            $ThisFileInfo['video']['bits_per_sample'] = $thisfile_bmp_header_raw['bits_per_pixel'];

            

            if (($thisfile_bmp['type_version'] >= 4) || ($thisfile_bmp_header_raw['compression'] == 3))

            {

                // should only be v4+, but BMPs with type_version==1 and BI_BITFIELDS compression have been seen
                $BMPheader .= fread($fd, 44);

                

                // BITMAPV4HEADER - [44 bytes] - http://msdn.microsoft.com/library/en-us/gdi/bitmaps_2k1e.asp
                // Win95+, WinNT4.0+
                // DWORD        bV4RedMask;
                // DWORD        bV4GreenMask;
                // DWORD        bV4BlueMask;
                // DWORD        bV4AlphaMask;
                // DWORD        bV4CSType;
                // CIEXYZTRIPLE bV4Endpoints;
                // DWORD        bV4GammaRed;
                // DWORD        bV4GammaGreen;
                // DWORD        bV4GammaBlue;
                $thisfile_bmp_header_raw['red_mask'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['green_mask'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['blue_mask'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['alpha_mask'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['cs_type'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['ciexyz_red'] = substr($BMPheader, $offset, 4);

                $offset += 4;

                $thisfile_bmp_header_raw['ciexyz_green'] = substr($BMPheader, $offset, 4);

                $offset += 4;

                $thisfile_bmp_header_raw['ciexyz_blue'] = substr($BMPheader, $offset, 4);

                $offset += 4;

                $thisfile_bmp_header_raw['gamma_red'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['gamma_green'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['gamma_blue'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                

                $thisfile_bmp_header['ciexyz_red'] = getid3_lib :: FixedPoint2_30(strrev($thisfile_bmp_header_raw['ciexyz_red']));

                $thisfile_bmp_header['ciexyz_green'] = getid3_lib :: FixedPoint2_30(strrev($thisfile_bmp_header_raw['ciexyz_green']));

                $thisfile_bmp_header['ciexyz_blue'] = getid3_lib :: FixedPoint2_30(strrev($thisfile_bmp_header_raw['ciexyz_blue']));

            }

            

            if ($thisfile_bmp['type_version'] >= 5)

            {

                $BMPheader .= fread($fd, 16);

                

                // BITMAPV5HEADER - [16 bytes] - http://msdn.microsoft.com/library/en-us/gdi/bitmaps_7c36.asp
                // Win98+, Win2000+
                // DWORD        bV5Intent;
                // DWORD        bV5ProfileData;
                // DWORD        bV5ProfileSize;
                // DWORD        bV5Reserved;
                $thisfile_bmp_header_raw['intent'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['profile_data_offset'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['profile_data_size'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

                $thisfile_bmp_header_raw['reserved3'] = getid3_lib :: LittleEndian2Int(substr($BMPheader, $offset, 4));

                $offset += 4;

            }

        

        }

        else

        {

            

            $ThisFileInfo['error'][] = 'Unknown BMP format in header.';

            return false;

        

        }

        

        if ($ExtractPalette || $ExtractData)

        {

            $PaletteEntries = 0;

            if ($thisfile_bmp_header_raw['bits_per_pixel'] < 16)

            {

                $PaletteEntries = pow(2, $thisfile_bmp_header_raw['bits_per_pixel']);

            }

            elseif (isset($thisfile_bmp_header_raw['colors_used']) && ($thisfile_bmp_header_raw['colors_used'] > 0) && ($thisfile_bmp_header_raw['colors_used'] <= 256))

            {

                $PaletteEntries = $thisfile_bmp_header_raw['colors_used'];

            }

            if ($PaletteEntries > 0)

            {

                $BMPpalette = fread($fd, 4 * $PaletteEntries);

                $paletteoffset = 0;

                for($i = 0; $i < $PaletteEntries; $i ++)

                {

                    // RGBQUAD          - http://msdn.microsoft.com/library/en-us/gdi/bitmaps_5f8y.asp
                    // BYTE    rgbBlue;
                    // BYTE    rgbGreen;
                    // BYTE    rgbRed;
                    // BYTE    rgbReserved;
                    $blue = getid3_lib :: LittleEndian2Int(substr($BMPpalette, $paletteoffset ++, 1));

                    $green = getid3_lib :: LittleEndian2Int(substr($BMPpalette, $paletteoffset ++, 1));

                    $red = getid3_lib :: LittleEndian2Int(substr($BMPpalette, $paletteoffset ++, 1));

                    if (($thisfile_bmp['type_os'] == 'OS/2') && ($thisfile_bmp['type_version'] == 1))

                    {

                        // no padding byte
                    }

                    else

                    {

                        $paletteoffset ++; // padding byte
                    }

                    $thisfile_bmp['palette'][$i] = (($red << 16) | ($green << 8) | $blue);

                }

            }

        }

        

        if ($ExtractData)

        {

            fseek($fd, $thisfile_bmp_header_raw['data_offset'], SEEK_SET);

            $RowByteLength = ceil(($thisfile_bmp_header_raw['width'] * ($thisfile_bmp_header_raw['bits_per_pixel'] / 8)) / 4) * 4; // round up to nearest DWORD boundry
            $BMPpixelData = fread($fd, $thisfile_bmp_header_raw['height'] * $RowByteLength);

            $pixeldataoffset = 0;

            switch (@$thisfile_bmp_header_raw['compression'])

            {

                

                case 0 : // BI_RGB
                    switch ($thisfile_bmp_header_raw['bits_per_pixel'])

                    {

                        case 1 :

                            for($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row --)

                            {

                                for($col = 0; $col < $thisfile_bmp_header_raw['width']; $col = $col)

                                {

                                    $paletteindexbyte = ord($BMPpixelData{$pixeldataoffset ++});

                                    for($i = 7; $i >= 0; $i --)

                                    {

                                        $paletteindex = ($paletteindexbyte & (0x01 << $i)) >> $i;

                                        $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindex];

                                        $col ++;

                                    }

                                }

                                while (($pixeldataoffset % 4) != 0)

                                {

                                    // lines are padded to nearest DWORD
                                    $pixeldataoffset ++;

                                }

                            }

                            break;

                        

                        case 4 :

                            for($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row --)

                            {

                                for($col = 0; $col < $thisfile_bmp_header_raw['width']; $col = $col)

                                {

                                    $paletteindexbyte = ord($BMPpixelData{$pixeldataoffset ++});

                                    for($i = 1; $i >= 0; $i --)

                                    {

                                        $paletteindex = ($paletteindexbyte & (0x0F << (4 * $i))) >> (4 * $i);

                                        $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindex];

                                        $col ++;

                                    }

                                }

                                while (($pixeldataoffset % 4) != 0)

                                {

                                    // lines are padded to nearest DWORD
                                    $pixeldataoffset ++;

                                }

                            }

                            break;

                        

                        case 8 :

                            for($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row --)

                            {

                                for($col = 0; $col < $thisfile_bmp_header_raw['width']; $col ++)

                                {

                                    $paletteindex = ord($BMPpixelData{$pixeldataoffset ++});

                                    $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindex];

                                }

                                while (($pixeldataoffset % 4) != 0)

                                {

                                    // lines are padded to nearest DWORD
                                    $pixeldataoffset ++;

                                }

                            }

                            break;

                        

                        case 24 :

                            for($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row --)

                            {

                                for($col = 0; $col < $thisfile_bmp_header_raw['width']; $col ++)

                                {

                                    $thisfile_bmp['data'][$row][$col] = (ord($BMPpixelData{$pixeldataoffset + 2}) << 16) | (ord($BMPpixelData{$pixeldataoffset + 1}) << 8) | ord($BMPpixelData{$pixeldataoffset});

                                    $pixeldataoffset += 3;

                                }

                                while (($pixeldataoffset % 4) != 0)

                                {

                                    // lines are padded to nearest DWORD
                                    $pixeldataoffset ++;

                                }

                            }

                            break;

                        

                        case 32 :

                            for($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row --)

                            {

                                for($col = 0; $col < $thisfile_bmp_header_raw['width']; $col ++)

                                {

                                    $thisfile_bmp['data'][$row][$col] = (ord($BMPpixelData{$pixeldataoffset + 3}) << 24) | (ord($BMPpixelData{$pixeldataoffset + 2}) << 16) | (ord($BMPpixelData{$pixeldataoffset + 1}) << 8) | ord($BMPpixelData{$pixeldataoffset});

                                    $pixeldataoffset += 4;

                                }

                                while (($pixeldataoffset % 4) != 0)

                                {

                                    // lines are padded to nearest DWORD
                                    $pixeldataoffset ++;

                                }

                            }

                            break;

                        

                        case 16 :

                            // ?
                            break;

                        

                        default :

                            $ThisFileInfo['error'][] = 'Unknown bits-per-pixel value (' . $thisfile_bmp_header_raw['bits_per_pixel'] . ') - cannot read pixel data';

                            break;

                    }

                    break;

                

                case 1 : // BI_RLE8 - http://msdn.microsoft.com/library/en-us/gdi/bitmaps_6x0u.asp
                    switch ($thisfile_bmp_header_raw['bits_per_pixel'])

                    {

                        case 8 :

                            $pixelcounter = 0;

                            while ($pixeldataoffset < strlen($BMPpixelData))

                            {

                                $firstbyte = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                $secondbyte = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                if ($firstbyte == 0)

                                {

                                    

                                    // escaped/absolute mode - the first byte of the pair can be set to zero to
                                    // indicate an escape character that denotes the end of a line, the end of
                                    // a bitmap, or a delta, depending on the value of the second byte.
                                    switch ($secondbyte)

                                    {

                                        case 0 :

                                            // end of line
                                            // no need for special processing, just ignore
                                            break;

                                        

                                        case 1 :

                                            // end of bitmap
                                            $pixeldataoffset = strlen($BMPpixelData); // force to exit loop just in case
                                            break;

                                        

                                        case 2 :

                                            // delta - The 2 bytes following the escape contain unsigned values
                                            // indicating the horizontal and vertical offsets of the next pixel
                                            // from the current position.
                                            $colincrement = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                            $rowincrement = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                            $col = ($pixelcounter % $thisfile_bmp_header_raw['width']) + $colincrement;

                                            $row = ($thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width'])) - $rowincrement;

                                            $pixelcounter = ($row * $thisfile_bmp_header_raw['width']) + $col;

                                            break;

                                        

                                        default :

                                            // In absolute mode, the first byte is zero and the second byte is a
                                            // value in the range 03H through FFH. The second byte represents the
                                            // number of bytes that follow, each of which contains the color index
                                            // of a single pixel. Each run must be aligned on a word boundary.
                                            for($i = 0; $i < $secondbyte; $i ++)

                                            {

                                                $paletteindex = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                                $col = $pixelcounter % $thisfile_bmp_header_raw['width'];

                                                $row = $thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width']);

                                                $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindex];

                                                $pixelcounter ++;

                                            }

                                            while (($pixeldataoffset % 2) != 0)

                                            {

                                                // Each run must be aligned on a word boundary.
                                                $pixeldataoffset ++;

                                            }

                                            break;

                                    }

                                

                                }

                                else

                                {

                                    

                                    // encoded mode - the first byte specifies the number of consecutive pixels
                                    // to be drawn using the color index contained in the second byte.
                                    for($i = 0; $i < $firstbyte; $i ++)

                                    {

                                        $col = $pixelcounter % $thisfile_bmp_header_raw['width'];

                                        $row = $thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width']);

                                        $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$secondbyte];

                                        $pixelcounter ++;

                                    }

                                

                                }

                            }

                            break;

                        

                        default :

                            $ThisFileInfo['error'][] = 'Unknown bits-per-pixel value (' . $thisfile_bmp_header_raw['bits_per_pixel'] . ') - cannot read pixel data';

                            break;

                    }

                    break;

                

                case 2 : // BI_RLE4 - http://msdn.microsoft.com/library/en-us/gdi/bitmaps_6x0u.asp
                    switch ($thisfile_bmp_header_raw['bits_per_pixel'])

                    {

                        case 4 :

                            $pixelcounter = 0;

                            while ($pixeldataoffset < strlen($BMPpixelData))

                            {

                                $firstbyte = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                $secondbyte = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                if ($firstbyte == 0)

                                {

                                    

                                    // escaped/absolute mode - the first byte of the pair can be set to zero to
                                    // indicate an escape character that denotes the end of a line, the end of
                                    // a bitmap, or a delta, depending on the value of the second byte.
                                    switch ($secondbyte)

                                    {

                                        case 0 :

                                            // end of line
                                            // no need for special processing, just ignore
                                            break;

                                        

                                        case 1 :

                                            // end of bitmap
                                            $pixeldataoffset = strlen($BMPpixelData); // force to exit loop just in case
                                            break;

                                        

                                        case 2 :

                                            // delta - The 2 bytes following the escape contain unsigned values
                                            // indicating the horizontal and vertical offsets of the next pixel
                                            // from the current position.
                                            $colincrement = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                            $rowincrement = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                            $col = ($pixelcounter % $thisfile_bmp_header_raw['width']) + $colincrement;

                                            $row = ($thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width'])) - $rowincrement;

                                            $pixelcounter = ($row * $thisfile_bmp_header_raw['width']) + $col;

                                            break;

                                        

                                        default :

                                            // In absolute mode, the first byte is zero. The second byte contains the number
                                            // of color indexes that follow. Subsequent bytes contain color indexes in their
                                            // high- and low-order 4 bits, one color index for each pixel. In absolute mode,
                                            // each run must be aligned on a word boundary.
                                            unset($paletteindexes);

                                            for($i = 0; $i < ceil($secondbyte / 2); $i ++)

                                            {

                                                $paletteindexbyte = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset ++, 1));

                                                $paletteindexes[] = ($paletteindexbyte & 0xF0) >> 4;

                                                $paletteindexes[] = ($paletteindexbyte & 0x0F);

                                            }

                                            while (($pixeldataoffset % 2) != 0)

                                            {

                                                // Each run must be aligned on a word boundary.
                                                $pixeldataoffset ++;

                                            }

                                            

                                            foreach ($paletteindexes as $paletteindex)

                                            {

                                                $col = $pixelcounter % $thisfile_bmp_header_raw['width'];

                                                $row = $thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width']);

                                                $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindex];

                                                $pixelcounter ++;

                                            }

                                            break;

                                    }

                                

                                }

                                else

                                {

                                    

                                    // encoded mode - the first byte of the pair contains the number of pixels to be
                                    // drawn using the color indexes in the second byte. The second byte contains two
                                    // color indexes, one in its high-order 4 bits and one in its low-order 4 bits.
                                    // The first of the pixels is drawn using the color specified by the high-order
                                    // 4 bits, the second is drawn using the color in the low-order 4 bits, the third
                                    // is drawn using the color in the high-order 4 bits, and so on, until all the
                                    // pixels specified by the first byte have been drawn.
                                    $paletteindexes[0] = ($secondbyte & 0xF0) >> 4;

                                    $paletteindexes[1] = ($secondbyte & 0x0F);

                                    for($i = 0; $i < $firstbyte; $i ++)

                                    {

                                        $col = $pixelcounter % $thisfile_bmp_header_raw['width'];

                                        $row = $thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width']);

                                        $thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindexes[($i % 2)]];

                                        $pixelcounter ++;

                                    }

                                

                                }

                            }

                            break;

                        

                        default :

                            $ThisFileInfo['error'][] = 'Unknown bits-per-pixel value (' . $thisfile_bmp_header_raw['bits_per_pixel'] . ') - cannot read pixel data';

                            break;

                    }

                    break;

                

                case 3 : // BI_BITFIELDS
                    switch ($thisfile_bmp_header_raw['bits_per_pixel'])

                    {

                        case 16 :

                        case 32 :

                            $redshift = 0;

                            $greenshift = 0;

                            $blueshift = 0;

                            while ((($thisfile_bmp_header_raw['red_mask'] >> $redshift) & 0x01) == 0)

                            {

                                $redshift ++;

                            }

                            while ((($thisfile_bmp_header_raw['green_mask'] >> $greenshift) & 0x01) == 0)

                            {

                                $greenshift ++;

                            }

                            while ((($thisfile_bmp_header_raw['blue_mask'] >> $blueshift) & 0x01) == 0)

                            {

                                $blueshift ++;

                            }

                            for($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row --)

                            {

                                for($col = 0; $col < $thisfile_bmp_header_raw['width']; $col ++)

                                {

                                    $pixelvalue = getid3_lib :: LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset, $thisfile_bmp_header_raw['bits_per_pixel'] / 8));

                                    $pixeldataoffset += $thisfile_bmp_header_raw['bits_per_pixel'] / 8;

                                    

                                    $red = intval(round(((($pixelvalue & $thisfile_bmp_header_raw['red_mask']) >> $redshift) / ($thisfile_bmp_header_raw['red_mask'] >> $redshift)) * 255));

                                    $green = intval(round(((($pixelvalue & $thisfile_bmp_header_raw['green_mask']) >> $greenshift) / ($thisfile_bmp_header_raw['green_mask'] >> $greenshift)) * 255));

                                    $blue = intval(round(((($pixelvalue & $thisfile_bmp_header_raw['blue_mask']) >> $blueshift) / ($thisfile_bmp_header_raw['blue_mask'] >> $blueshift)) * 255));

                                    $thisfile_bmp['data'][$row][$col] = (($red << 16) | ($green << 8) | ($blue));

                                }

                                while (($pixeldataoffset % 4) != 0)

                                {

                                    // lines are padded to nearest DWORD
                                    $pixeldataoffset ++;

                                }

                            }

                            break;

                        

                        default :

                            $ThisFileInfo['error'][] = 'Unknown bits-per-pixel value (' . $thisfile_bmp_header_raw['bits_per_pixel'] . ') - cannot read pixel data';

                            break;

                    }

                    break;

                

                default : // unhandled compression type
                    $ThisFileInfo['error'][] = 'Unknown/unhandled compression type value (' . $thisfile_bmp_header_raw['compression'] . ') - cannot decompress pixel data';

                    break;

            }

        }

        

        return true;

    }



    function PlotBMP(&$BMPinfo)

    {

        $starttime = time();

        if (! isset($BMPinfo['bmp']['data']) || ! is_array($BMPinfo['bmp']['data']))

        {

            echo 'ERROR: no pixel data<BR>';

            return false;

        }

        set_time_limit(intval(round($BMPinfo['resolution_x'] * $BMPinfo['resolution_y'] / 10000)));

        if ($im = ImageCreateTrueColor($BMPinfo['resolution_x'], $BMPinfo['resolution_y']))

        {

            for($row = 0; $row < $BMPinfo['resolution_y']; $row ++)

            {

                for($col = 0; $col < $BMPinfo['resolution_x']; $col ++)

                {

                    if (isset($BMPinfo['bmp']['data'][$row][$col]))

                    {

                        $red = ($BMPinfo['bmp']['data'][$row][$col] & 0x00FF0000) >> 16;

                        $green = ($BMPinfo['bmp']['data'][$row][$col] & 0x0000FF00) >> 8;

                        $blue = ($BMPinfo['bmp']['data'][$row][$col] & 0x000000FF);

                        $pixelcolor = ImageColorAllocate($im, $red, $green, $blue);

                        ImageSetPixel($im, $col, $row, $pixelcolor);

                    }

                    else

                    {

                        //echo 'ERROR: no data for pixel '.$row.' x '.$col.'<BR>';
                    //return false;
                    }

                }

            }

            if (headers_sent())

            {

                echo 'plotted ' . ($BMPinfo['resolution_x'] * $BMPinfo['resolution_y']) . ' pixels in ' . (time() - $starttime) . ' seconds<BR>';

                ImageDestroy($im);

                exit();

            }

            else

            {

                header('Content-type: image/png');

                ImagePNG($im);

                ImageDestroy($im);

                return true;

            }

        }

        return false;

    }



    function BMPcompressionWindowsLookup($compressionid)

    {

        static $BMPcompressionWindowsLookup = array(0 => 'BI_RGB', 1 => 'BI_RLE8', 2 => 'BI_RLE4', 3 => 'BI_BITFIELDS', 

                4 => 'BI_JPEG', 5 => 'BI_PNG');

        return (isset($BMPcompressionWindowsLookup[$compressionid]) ? $BMPcompressionWindowsLookup[$compressionid] : 'invalid');

    }



    function BMPcompressionOS2Lookup($compressionid)

    {

        static $BMPcompressionOS2Lookup = array(0 => 'BI_RGB', 1 => 'BI_RLE8', 2 => 'BI_RLE4', 3 => 'Huffman 1D', 

                4 => 'BI_RLE24');

        return (isset($BMPcompressionOS2Lookup[$compressionid]) ? $BMPcompressionOS2Lookup[$compressionid] : 'invalid');

    }



}



?>