using System;
using System.IO;
using iTextSharp.text;
using iTextSharp.text.pdf;
using System.util.zlib;
using iTextSharp.text.error_messages;
/*
 * This file is part of the iText project.
 * Copyright (c) 1998-2012 1T3XT BVBA
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * you must retain the producer line in every PDF that is created or manipulated
 * using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */

namespace iTextSharp.text.pdf.codec {
    /** Reads TIFF images
    * @author Paulo Soares
    */
    public class TiffImage {
        
        /** Gets the number of pages the TIFF document has.
        * @param s the file source
        * @return the number of pages
        */    
        public static int GetNumberOfPages(RandomAccessFileOrArray s) {
            return TIFFDirectory.GetNumDirectories(s);
        }

        static int GetDpi(TIFFField fd, int resolutionUnit) {
            if (fd == null)
                return 0;
            long[] res = fd.GetAsRational(0);
            float frac = (float)res[0] / (float)res[1];
            int dpi = 0;
            switch (resolutionUnit) {
                case TIFFConstants.RESUNIT_INCH:
                case TIFFConstants.RESUNIT_NONE:
                    dpi = (int)(frac + 0.5);
                    break;
                case TIFFConstants.RESUNIT_CENTIMETER:
                    dpi = (int)(frac * 2.54 + 0.5);
                    break;
            }
            return dpi;
        }
        
        /** Reads a page from a TIFF image. Direct mode is not used.
        * @param s the file source
        * @param page the page to get. The first page is 1
        * @return the <CODE>Image</CODE>
        */    
        public static Image GetTiffImage(RandomAccessFileOrArray s, int page) {
            return GetTiffImage(s, page, false);
        }
        
        /** Reads a page from a TIFF image.
        * @param s the file source
        * @param page the page to get. The first page is 1
        * @param direct for single strip, CCITT images, generate the image
        * by direct byte copying. It's faster but may not work
        * every time
        * @return the <CODE>Image</CODE>
        */    
        public static Image GetTiffImage(RandomAccessFileOrArray s, int page, bool direct) {
            if (page < 1)
                throw new ArgumentException(MessageLocalization.GetComposedMessage("the.page.number.must.be.gt.eq.1"));
            TIFFDirectory dir = new TIFFDirectory(s, page - 1);
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_TILEWIDTH))
                throw new ArgumentException(MessageLocalization.GetComposedMessage("tiles.are.not.supported"));
            int compression = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_COMPRESSION);
            switch (compression) {
                case TIFFConstants.COMPRESSION_CCITTRLEW:
                case TIFFConstants.COMPRESSION_CCITTRLE:
                case TIFFConstants.COMPRESSION_CCITTFAX3:
                case TIFFConstants.COMPRESSION_CCITTFAX4:
                    break;
                default:
                    return GetTiffImageColor(dir, s);
            }
            float rotation = 0;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_ORIENTATION)) {
                int rot = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_ORIENTATION);
                if (rot == TIFFConstants.ORIENTATION_BOTRIGHT || rot == TIFFConstants.ORIENTATION_BOTLEFT)
                    rotation = (float)Math.PI;
                else if (rot == TIFFConstants.ORIENTATION_LEFTTOP || rot == TIFFConstants.ORIENTATION_LEFTBOT)
                    rotation = (float)(Math.PI / 2.0);
                else if (rot == TIFFConstants.ORIENTATION_RIGHTTOP || rot == TIFFConstants.ORIENTATION_RIGHTBOT)
                    rotation = -(float)(Math.PI / 2.0);
            }

            Image img = null;
            long tiffT4Options = 0;
            long tiffT6Options = 0;
            int fillOrder = 1;
            int h = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_IMAGELENGTH);
            int w = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_IMAGEWIDTH);
            int dpiX = 0;
            int dpiY = 0;
            float XYRatio = 0;
            int resolutionUnit = TIFFConstants.RESUNIT_INCH;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_RESOLUTIONUNIT))
                resolutionUnit = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_RESOLUTIONUNIT);
            dpiX = GetDpi(dir.GetField(TIFFConstants.TIFFTAG_XRESOLUTION), resolutionUnit);
            dpiY = GetDpi(dir.GetField(TIFFConstants.TIFFTAG_YRESOLUTION), resolutionUnit);
            if (resolutionUnit == TIFFConstants.RESUNIT_NONE) {
                if (dpiY != 0)
                    XYRatio = (float)dpiX / (float)dpiY;
                dpiX = 0;
                dpiY = 0;
            }
            int rowsStrip = h;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_ROWSPERSTRIP))
                rowsStrip = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_ROWSPERSTRIP);
            if (rowsStrip <= 0 || rowsStrip > h)
                rowsStrip = h;
            long[] offset = GetArrayLongShort(dir, TIFFConstants.TIFFTAG_STRIPOFFSETS);
            long[] size = GetArrayLongShort(dir, TIFFConstants.TIFFTAG_STRIPBYTECOUNTS);
            if ((size == null || (size.Length == 1 && (size[0] == 0 || size[0] + offset[0] > s.Length))) && h == rowsStrip) { // some TIFF producers are really lousy, so...
                size = new long[]{s.Length - (int)offset[0]};
            }
            bool reverse = false;
            TIFFField fillOrderField =  dir.GetField(TIFFConstants.TIFFTAG_FILLORDER);
            if (fillOrderField != null)
                fillOrder = fillOrderField.GetAsInt(0);
            reverse = (fillOrder == TIFFConstants.FILLORDER_LSB2MSB);
            int paramsn = 0;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_PHOTOMETRIC)) {
                long photo = dir.GetFieldAsLong(TIFFConstants.TIFFTAG_PHOTOMETRIC);
                if (photo == TIFFConstants.PHOTOMETRIC_MINISBLACK)
                    paramsn |= Image.CCITT_BLACKIS1;
            }
            int imagecomp = 0;
            switch (compression) {
                case TIFFConstants.COMPRESSION_CCITTRLEW:
                case TIFFConstants.COMPRESSION_CCITTRLE:
                    imagecomp = Image.CCITTG3_1D;
                    paramsn |= Image.CCITT_ENCODEDBYTEALIGN | Image.CCITT_ENDOFBLOCK;
                    break;
                case TIFFConstants.COMPRESSION_CCITTFAX3:
                    imagecomp = Image.CCITTG3_1D;
                    paramsn |= Image.CCITT_ENDOFLINE | Image.CCITT_ENDOFBLOCK;
                    TIFFField t4OptionsField = dir.GetField(TIFFConstants.TIFFTAG_GROUP3OPTIONS);
                    if (t4OptionsField != null) {
                        tiffT4Options = t4OptionsField.GetAsLong(0);
                    if ((tiffT4Options & TIFFConstants.GROUP3OPT_2DENCODING) != 0)
                        imagecomp = Image.CCITTG3_2D;
                    if ((tiffT4Options & TIFFConstants.GROUP3OPT_FILLBITS) != 0)
                        paramsn |= Image.CCITT_ENCODEDBYTEALIGN;
                    }
                    break;
                case TIFFConstants.COMPRESSION_CCITTFAX4:
                    imagecomp = Image.CCITTG4;
                    TIFFField t6OptionsField = dir.GetField(TIFFConstants.TIFFTAG_GROUP4OPTIONS);
                    if (t6OptionsField != null)
                        tiffT6Options = t6OptionsField.GetAsLong(0);
                    break;
            }
            if (direct && rowsStrip == h) { //single strip, direct
                byte[] im = new byte[(int)size[0]];
                s.Seek(offset[0]);
                s.ReadFully(im);
                img = Image.GetInstance(w, h, false, imagecomp, paramsn, im);
                img.Inverted = true;
            }
            else {
                int rowsLeft = h;
                CCITTG4Encoder g4 = new CCITTG4Encoder(w);
                for (int k = 0; k < offset.Length; ++k) {
                    byte[] im = new byte[(int)size[k]];
                    s.Seek(offset[k]);
                    s.ReadFully(im);
                    int height = Math.Min(rowsStrip, rowsLeft);
                    TIFFFaxDecoder decoder = new TIFFFaxDecoder(fillOrder, w, height);
                    byte[] outBuf = new byte[(w + 7) / 8 * height];
                    switch (compression) {
                        case TIFFConstants.COMPRESSION_CCITTRLEW:
                        case TIFFConstants.COMPRESSION_CCITTRLE:
                            decoder.Decode1D(outBuf, im, 0, height);
                            g4.Fax4Encode(outBuf, height);
                            break;
                        case TIFFConstants.COMPRESSION_CCITTFAX3:
                            try {
                                decoder.Decode2D(outBuf, im, 0, height, tiffT4Options);
                            }
                            catch (Exception e) {
                                // let's flip the fill bits and try again...
                                tiffT4Options ^= TIFFConstants.GROUP3OPT_FILLBITS;
                                try {
                                    decoder.Decode2D(outBuf, im, 0, height, tiffT4Options);
                                }
                                catch {
                                    throw e;
                                }
                            }
                            g4.Fax4Encode(outBuf, height);
                            break;
                        case TIFFConstants.COMPRESSION_CCITTFAX4:
                            decoder.DecodeT6(outBuf, im, 0, height, tiffT6Options);
                            g4.Fax4Encode(outBuf, height);
                            break;
                    }
                    rowsLeft -= rowsStrip;
                }
                byte[] g4pic = g4.Close();
                img = Image.GetInstance(w, h, false, Image.CCITTG4, paramsn & Image.CCITT_BLACKIS1, g4pic);
            }
            img.SetDpi(dpiX, dpiY);
            img.XYRatio = XYRatio;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_ICCPROFILE)) {
                try {
                    TIFFField fd = dir.GetField(TIFFConstants.TIFFTAG_ICCPROFILE);
                    ICC_Profile icc_prof = ICC_Profile.GetInstance(fd.GetAsBytes());
                    if (icc_prof.NumComponents == 1)
                        img.TagICC = icc_prof;
                }
                catch {
                    //empty
                }
            }
            img.OriginalType = Image.ORIGINAL_TIFF;
            if (rotation != 0)
                img.InitialRotation = rotation;
            return img;
        }
        
        protected static Image GetTiffImageColor(TIFFDirectory dir, RandomAccessFileOrArray s) {
            int predictor = 1;
            TIFFLZWDecoder lzwDecoder = null;
            int compression = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_COMPRESSION);
            switch (compression) {
                case TIFFConstants.COMPRESSION_NONE:
                case TIFFConstants.COMPRESSION_LZW:
                case TIFFConstants.COMPRESSION_PACKBITS:
                case TIFFConstants.COMPRESSION_DEFLATE:
                case TIFFConstants.COMPRESSION_ADOBE_DEFLATE:
                case TIFFConstants.COMPRESSION_OJPEG:
                case TIFFConstants.COMPRESSION_JPEG:
                    break;
                default:
                    throw new ArgumentException(MessageLocalization.GetComposedMessage("the.compression.1.is.not.supported", compression));
            }
            int photometric = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_PHOTOMETRIC);
            switch (photometric) {
                case TIFFConstants.PHOTOMETRIC_MINISWHITE:
                case TIFFConstants.PHOTOMETRIC_MINISBLACK:
                case TIFFConstants.PHOTOMETRIC_RGB:
                case TIFFConstants.PHOTOMETRIC_SEPARATED:
                case TIFFConstants.PHOTOMETRIC_PALETTE:
                    break;
                default:
                    if (compression != TIFFConstants.COMPRESSION_OJPEG && compression != TIFFConstants.COMPRESSION_JPEG)
                        throw new ArgumentException(MessageLocalization.GetComposedMessage("the.photometric.1.is.not.supported", photometric));
                    break;
            }
            float rotation = 0;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_ORIENTATION)) {
                int rot = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_ORIENTATION);
                if (rot == TIFFConstants.ORIENTATION_BOTRIGHT || rot == TIFFConstants.ORIENTATION_BOTLEFT)
                    rotation = (float)Math.PI;
                else if (rot == TIFFConstants.ORIENTATION_LEFTTOP || rot == TIFFConstants.ORIENTATION_LEFTBOT)
                    rotation = (float)(Math.PI / 2.0);
                else if (rot == TIFFConstants.ORIENTATION_RIGHTTOP || rot == TIFFConstants.ORIENTATION_RIGHTBOT)
                    rotation = -(float)(Math.PI / 2.0);
            }

            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_PLANARCONFIG)
                && dir.GetFieldAsLong(TIFFConstants.TIFFTAG_PLANARCONFIG) == TIFFConstants.PLANARCONFIG_SEPARATE)
                throw new ArgumentException(MessageLocalization.GetComposedMessage("planar.images.are.not.supported"));
            int extraSamples = 0;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_EXTRASAMPLES))
                extraSamples = 1;
            int samplePerPixel = 1;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_SAMPLESPERPIXEL)) // 1,3,4
                samplePerPixel = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_SAMPLESPERPIXEL);
            int bitsPerSample = 1;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_BITSPERSAMPLE))
                bitsPerSample = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_BITSPERSAMPLE);
            switch (bitsPerSample) {
                case 1:
                case 2:
                case 4:
                case 8:
                    break;
                default:
                    throw new ArgumentException(MessageLocalization.GetComposedMessage("bits.per.sample.1.is.not.supported", bitsPerSample));
            }
            Image img = null;

            int h = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_IMAGELENGTH);
            int w = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_IMAGEWIDTH);
            int dpiX = 0;
            int dpiY = 0;
            int resolutionUnit = TIFFConstants.RESUNIT_INCH;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_RESOLUTIONUNIT))
                resolutionUnit = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_RESOLUTIONUNIT);
            dpiX = GetDpi(dir.GetField(TIFFConstants.TIFFTAG_XRESOLUTION), resolutionUnit);
            dpiY = GetDpi(dir.GetField(TIFFConstants.TIFFTAG_YRESOLUTION), resolutionUnit);
            int fillOrder = 1;
            bool reverse = false;
            TIFFField fillOrderField =  dir.GetField(TIFFConstants.TIFFTAG_FILLORDER);
            if (fillOrderField != null)
                fillOrder = fillOrderField.GetAsInt(0);
            reverse = (fillOrder == TIFFConstants.FILLORDER_LSB2MSB);
            int rowsStrip = h;
            if (dir.IsTagPresent(TIFFConstants.TIFFTAG_ROWSPERSTRIP)) //another hack for broken tiffs
                rowsStrip = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_ROWSPERSTRIP);
            if (rowsStrip <= 0 || rowsStrip > h)
                rowsStrip = h;
            long[] offset = GetArrayLongShort(dir, TIFFConstants.TIFFTAG_STRIPOFFSETS);
            long[] size = GetArrayLongShort(dir, TIFFConstants.TIFFTAG_STRIPBYTECOUNTS);
            if ((size == null || (size.Length == 1 && (size[0] == 0 || size[0] + offset[0] > s.Length))) && h == rowsStrip) { // some TIFF producers are really lousy, so...
                size = new long[]{s.Length - (int)offset[0]};
            }
            if (compression == TIFFConstants.COMPRESSION_LZW) {
                TIFFField predictorField = dir.GetField(TIFFConstants.TIFFTAG_PREDICTOR);
                if (predictorField != null) {
                    predictor = predictorField.GetAsInt(0);
                    if (predictor != 1 && predictor != 2) {
                        throw new Exception(MessageLocalization.GetComposedMessage("illegal.value.for.predictor.in.tiff.file"));
                    }
                    if (predictor == 2 && bitsPerSample != 8) {
                        throw new Exception(MessageLocalization.GetComposedMessage("1.bit.samples.are.not.supported.for.horizontal.differencing.predictor", bitsPerSample));
                    }
                }
                lzwDecoder = new TIFFLZWDecoder(w, predictor, 
                                                samplePerPixel); 
            }
            int rowsLeft = h;
            MemoryStream stream = null;
            MemoryStream mstream = null;
            ZDeflaterOutputStream zip = null;
            ZDeflaterOutputStream mzip = null;
            if (extraSamples > 0) {
                mstream = new MemoryStream();
                mzip = new ZDeflaterOutputStream(mstream);
            }

            CCITTG4Encoder g4 = null;
            if (bitsPerSample == 1 && samplePerPixel == 1 && photometric != TIFFConstants.PHOTOMETRIC_PALETTE) {
                g4 = new CCITTG4Encoder(w);
            }
            else {
                stream = new MemoryStream();
                if (compression != TIFFConstants.COMPRESSION_OJPEG && compression != TIFFConstants.COMPRESSION_JPEG)
                    zip = new ZDeflaterOutputStream(stream);
            }
            if (compression == TIFFConstants.COMPRESSION_OJPEG) {

                // Assume that the TIFFTAG_JPEGIFBYTECOUNT tag is optional, since it's obsolete and 
                // is often missing

                if ((!dir.IsTagPresent(TIFFConstants.TIFFTAG_JPEGIFOFFSET))) {
                    throw new IOException(MessageLocalization.GetComposedMessage("missing.tag.s.for.ojpeg.compression"));
                }
                int jpegOffset = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_JPEGIFOFFSET);
                int jpegLength = (int)s.Length - jpegOffset;

                if (dir.IsTagPresent(TIFFConstants.TIFFTAG_JPEGIFBYTECOUNT)) {
                    jpegLength = (int)dir.GetFieldAsLong(TIFFConstants.TIFFTAG_JPEGIFBYTECOUNT) +
                        (int)size[0];
                }

                byte[] jpeg = new byte[Math.Min(jpegLength, s.Length - jpegOffset)];

                int posFilePointer = (int)s.FilePointer;
                posFilePointer += jpegOffset;
                s.Seek(posFilePointer);
                s.ReadFully(jpeg);
                img = new Jpeg(jpeg);
            } 
            else if (compression == TIFFConstants.COMPRESSION_JPEG) {
                if (size.Length > 1)
                    throw new IOException(MessageLocalization.GetComposedMessage("compression.jpeg.is.only.supported.with.a.single.strip.this.image.has.1.strips", size.Length));
                byte[] jpeg = new byte[(int)size[0]];
                s.Seek(offset[0]);
                s.ReadFully(jpeg);
                img = new Jpeg(jpeg);
            } 
            else {
                for (int k = 0; k < offset.Length; ++k) {
                    byte[] im = new byte[(int)size[k]];
                    s.Seek(offset[k]);
                    s.ReadFully(im);
                    int height = Math.Min(rowsStrip, rowsLeft);
                    byte[] outBuf = null;
                    if (compression != TIFFConstants.COMPRESSION_NONE)
                        outBuf = new byte[(w * bitsPerSample * samplePerPixel + 7) / 8 * height];
                    if (reverse)
                        TIFFFaxDecoder.ReverseBits(im);
                    switch (compression) {
                        case TIFFConstants.COMPRESSION_DEFLATE:
                        case TIFFConstants.COMPRESSION_ADOBE_DEFLATE:
                            Inflate(im, outBuf);
                            break;
                        case TIFFConstants.COMPRESSION_NONE:
                            outBuf = im;
                            break;
                        case TIFFConstants.COMPRESSION_PACKBITS:
                            DecodePackbits(im,  outBuf);
                            break;
                        case TIFFConstants.COMPRESSION_LZW:
                            lzwDecoder.Decode(im, outBuf, height);
                            break;
                    }
                    if (bitsPerSample == 1 && samplePerPixel == 1 && photometric != TIFFConstants.PHOTOMETRIC_PALETTE) {
                        g4.Fax4Encode(outBuf, height);
                    }
                    else {
                        if (extraSamples > 0)
                            ProcessExtraSamples(zip, mzip, outBuf, samplePerPixel, bitsPerSample, w, height);
                        else
                            zip.Write(outBuf, 0, outBuf.Length);
                    }
                    rowsLeft -= rowsStrip;
                }
                if (bitsPerSample == 1 && samplePerPixel == 1 && photometric != TIFFConstants.PHOTOMETRIC_PALETTE) {
                    img = Image.GetInstance(w, h, false, Image.CCITTG4, 
                        photometric == TIFFConstants.PHOTOMETRIC_MINISBLACK ? Image.CCITT_BLACKIS1 : 0, g4.Close());
                }
                else {
                    zip.Close();
                    img = new ImgRaw(w, h, samplePerPixel - extraSamples, bitsPerSample, stream.ToArray());
                    img.Deflated = true;
                }
            }
            img.SetDpi(dpiX, dpiY);
            if (compression != TIFFConstants.COMPRESSION_OJPEG && compression != TIFFConstants.COMPRESSION_JPEG) {
                if (dir.IsTagPresent(TIFFConstants.TIFFTAG_ICCPROFILE)) {
                    try {
                        TIFFField fd = dir.GetField(TIFFConstants.TIFFTAG_ICCPROFILE);
                        ICC_Profile icc_prof = ICC_Profile.GetInstance(fd.GetAsBytes());
                        if (samplePerPixel - extraSamples == icc_prof.NumComponents)
                            img.TagICC = icc_prof;
                    }
                    catch {
                        //empty
                    }
                }
                if (dir.IsTagPresent(TIFFConstants.TIFFTAG_COLORMAP)) {
                    TIFFField fd = dir.GetField(TIFFConstants.TIFFTAG_COLORMAP);
                    char[] rgb = fd.GetAsChars();
                    byte[] palette = new byte[rgb.Length];
                    int gColor = rgb.Length / 3;
                    int bColor = gColor * 2;
                    for (int k = 0; k < gColor; ++k) {
                        palette[k * 3] = (byte)(rgb[k] >> 8);
                        palette[k * 3 + 1] = (byte)(rgb[k + gColor] >> 8);
                        palette[k * 3 + 2] = (byte)(rgb[k + bColor] >> 8);
                    }
                    PdfArray indexed = new PdfArray();
                    indexed.Add(PdfName.INDEXED);
                    indexed.Add(PdfName.DEVICERGB);
                    indexed.Add(new PdfNumber(gColor - 1));
                    indexed.Add(new PdfString(palette));
                    PdfDictionary additional = new PdfDictionary();
                    additional.Put(PdfName.COLORSPACE, indexed);
                    img.Additional = additional;
                }
                img.OriginalType = Image.ORIGINAL_TIFF;
            }
            if (photometric == TIFFConstants.PHOTOMETRIC_MINISWHITE)
                img.Inverted = true;
            if (rotation != 0)
                img.InitialRotation = rotation;
            if (extraSamples > 0) {
                mzip.Close();
                Image mimg = Image.GetInstance(w, h, 1, bitsPerSample, mstream.ToArray());
                mimg.MakeMask();
                mimg.Deflated = true;
                img.ImageMask = mimg;
            }
            return img;
        }
        
        static Image ProcessExtraSamples(ZDeflaterOutputStream zip, ZDeflaterOutputStream mzip, byte[] outBuf, int samplePerPixel, int bitsPerSample, int width, int height) {
            if (bitsPerSample == 8) {
                byte[] mask = new byte[width * height];
                int mptr = 0;
                int optr = 0;
                int total = width * height * samplePerPixel;
                for (int k = 0; k < total; k += samplePerPixel) {
                    for (int s = 0; s < samplePerPixel - 1; ++s) {
                        outBuf[optr++] = outBuf[k + s];
                    }
                    mask[mptr++] = outBuf[k + samplePerPixel - 1];
                }
                zip.Write(outBuf, 0, optr);
                mzip.Write(mask, 0, mptr);
            }
            else
                throw new ArgumentException(MessageLocalization.GetComposedMessage("extra.samples.are.not.supported"));
            return null;
        }

        static long[] GetArrayLongShort(TIFFDirectory dir, int tag) {
            TIFFField field = dir.GetField(tag);
            if (field == null)
                return null;
            long[] offset;
            if (field.GetType() == TIFFField.TIFF_LONG)
                offset = field.GetAsLongs();
            else { // must be short
                char[] temp = field.GetAsChars();
                offset = new long[temp.Length];
                for (int k = 0; k < temp.Length; ++k)
                    offset[k] = temp[k];
            }
            return offset;
        }
        
        // Uncompress packbits compressed image data.
        public static void DecodePackbits(byte[] data, byte[] dst) {
            int srcCount = 0, dstCount = 0;
            sbyte repeat, b;
            
            try {
                while (dstCount < dst.Length) {
                    b = (sbyte)data[srcCount++];
                    if (b >= 0 && b <= 127) {
                        // literal run packet
                        for (int i=0; i<(b + 1); i++) {
                            dst[dstCount++] = data[srcCount++];
                        }

                    } else if (b <= -1 && b >= -127) {
                        // 2 byte encoded run packet
                        repeat = (sbyte)data[srcCount++];
                        for (int i=0; i<(-b + 1); i++) {
                            dst[dstCount++] = (byte)repeat;
                        }
                    } else {
                        // no-op packet. Do nothing
                        srcCount++;
                    }
                }
            }
            catch {
            }
        }

        public static void Inflate(byte[] deflated, byte[] inflated) {
            byte[] outp = PdfReader.FlateDecode(deflated);
            System.Array.Copy(outp, 0, inflated, 0, Math.Min(outp.Length, inflated.Length));
        }
    }
}
