tiffio.c

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/*====================================================================*
 -  Copyright (C) 2001 Leptonica.  All rights reserved.
 -
 -  Redistribution and use in source and binary forms, with or without
 -  modification, are permitted provided that the following conditions
 -  are met:
 -  1. Redistributions of source code must retain the above copyright
 -     notice, this list of conditions and the following disclaimer.
 -  2. Redistributions in binary form must reproduce the above
 -     copyright notice, this list of conditions and the following
 -     disclaimer in the documentation and/or other materials
 -     provided with the distribution.
 -
 -  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 -  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 -  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 -  A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ANY
 -  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 -  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 -  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 -  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 -  OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 -  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 -  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *====================================================================*/
 
#ifdef HAVE_CONFIG_H
#include <config_auto.h>
#endif  /* HAVE_CONFIG_H */
 
#include <string.h>
#include <math.h>   /* for isnan */
#include <sys/types.h>
#ifndef _MSC_VER
#include <unistd.h>
#else  /* _MSC_VER */
#include <io.h>
#endif  /* _MSC_VER */
#include <fcntl.h>
#include "allheaders.h"
 
/* --------------------------------------------*/
#if  HAVE_LIBTIFF   /* defined in environ.h */
/* --------------------------------------------*/
 
#include "tiff.h"
#include "tiffio.h"
 
static const l_int32  DefaultResolution = 300;   /* ppi */
static const l_int32  ManyPagesInTiffFile = 3000;  /* warn if big */
 
    /* Verified that tiflib makes valid g4 files of this size */
static const l_int32  MaxTiffWidth = 1 << 20;  /* 1M pixels */
static const l_int32  MaxTiffHeight = 1 << 20;  /* 1M pixels */
 
    /* Check g4 data size */
static const size_t  MaxNumTiffBytes = (1 << 28) - 1;  /* 256 MB */
 
    /* All functions with TIFF interfaces are static. */
static PIX      *pixReadFromTiffStream(TIFF *tif);
static l_int32   getTiffStreamResolution(TIFF *tif, l_int32 *pxres,
                                         l_int32 *pyres);
static l_int32   tiffReadHeaderTiff(TIFF *tif, l_int32 *pwidth,
                                    l_int32 *pheight, l_int32 *pbps,
                                    l_int32 *pspp, l_int32 *pres,
                                    l_int32 *pcmap, l_int32 *pformat);
static l_int32   writeCustomTiffTags(TIFF *tif, NUMA *natags,
                                     SARRAY *savals, SARRAY  *satypes,
                                     NUMA *nasizes);
static l_int32   pixWriteToTiffStream(TIFF *tif, PIX *pix, l_int32 comptype,
                                      NUMA *natags, SARRAY *savals,
                                      SARRAY *satypes, NUMA *nasizes);
static TIFF     *fopenTiff(FILE *fp, const char *modestring);
static TIFF     *openTiff(const char *filename, const char *modestring);
 
    /* Static helper for tiff compression type */
static l_int32   getTiffCompressedFormat(l_uint16 tiffcomp);
 
    /* Static function for memory I/O */
static TIFF     *fopenTiffMemstream(const char *filename, const char *operation,
                                    l_uint8 **pdata, size_t *pdatasize);
 
    /* This structure defines a transform to be performed on a TIFF image
     * (note that the same transformation can be represented in
     * several different ways using this structure since
     * vflip + hflip + counterclockwise == clockwise). */
struct tiff_transform {
    int vflip;    /* if non-zero, image needs a vertical fip */
    int hflip;    /* if non-zero, image needs a horizontal flip */
    int rotate;   /* -1 -> counterclockwise 90-degree rotation,
                      0 -> no rotation
                      1 -> clockwise 90-degree rotation */
};
 
    /* This describes the transformations needed for a given orientation
     * tag.  The tag values start at 1, so you need to subtract 1 to get a
     * valid index into this array.  It is only valid when not using
     * TIFFReadRGBAImageOriented(). */
static struct tiff_transform tiff_orientation_transforms[] = {
    {0, 0, 0},
    {0, 1, 0},
    {1, 1, 0},
    {1, 0, 0},
    {0, 1, -1},
    {0, 0, 1},
    {0, 1, 1},
    {0, 0, -1}
};
 
    /* Same as above, except that test transformations are only valid
     * when using TIFFReadRGBAImageOriented().  Transformations
     * were determined empirically.  See the libtiff mailing list for
     * more discussion: http://www.asmail.be/msg0054683875.html  */
static struct tiff_transform tiff_partial_orientation_transforms[] = {
    {0, 0, 0},
    {0, 0, 0},
    {0, 0, 0},
    {0, 0, 0},
    {0, 1, -1},
    {0, 1, 1},
    {1, 0, 1},
    {0, 1, -1}
};
 
 
/*-----------------------------------------------------------------------*
 *             TIFFClientOpen() wrappers for FILE*                       *
 *             Provided by Jürgen Buchmüller                             *
 *                                                                       *
 *  We previously used TIFFFdOpen(), which used low-level file           *
 *  descriptors.  It had portability issues with Windows, along          *
 *  with other limitations from lack of stream control operations.       *
 *  These callbacks to TIFFClientOpen() avoid the problems.              *
 *                                                                       *
 *  Jürgen made the functions use 64 bit file operations where possible  *
 *  or required, namely for seek and size. On Windows there are specific *
 *  _fseeki64() and _ftelli64() functions.  On unix it is common to look *
 *  for a macro _LARGEFILE64_SOURCE being defined, which makes available *
 *  the off64_t type, and to use fseeko() and ftello() in this case.     *
 *-----------------------------------------------------------------------*/
static tsize_t
lept_read_proc(thandle_t  cookie,
               tdata_t    buff,
               tsize_t    size)
{
    FILE* fp = (FILE *)cookie;
    tsize_t done;
    if (!buff || !cookie || !fp)
        return (tsize_t)-1;
    done = fread(buff, 1, size, fp);
    return done;
}
 
static tsize_t
lept_write_proc(thandle_t  cookie,
                tdata_t    buff,
                tsize_t    size)
{
    FILE* fp = (FILE *)cookie;
    tsize_t done;
    if (!buff || !cookie || !fp)
        return (tsize_t)-1;
    done = fwrite(buff, 1, size, fp);
    return done;
}
 
static toff_t
lept_seek_proc(thandle_t  cookie,
               toff_t     offs,
               int        whence)
{
    FILE* fp = (FILE *)cookie;
#if defined(_MSC_VER)
    __int64 pos = 0;
    if (!cookie || !fp)
        return (tsize_t)-1;
    switch (whence) {
    case SEEK_SET:
        pos = 0;
        break;
    case SEEK_CUR:
        pos = ftell(fp);
        break;
    case SEEK_END:
        _fseeki64(fp, 0, SEEK_END);
        pos = _ftelli64(fp);
        break;
    }
    pos = (__int64)(pos + offs);
    _fseeki64(fp, pos, SEEK_SET);
    if (pos == _ftelli64(fp))
        return (tsize_t)pos;
#elif defined(_LARGEFILE64_SOURCE)
    off64_t pos = 0;
    if (!cookie || !fp)
        return (tsize_t)-1;
    switch (whence) {
    case SEEK_SET:
        pos = 0;
        break;
    case SEEK_CUR:
        pos = ftello(fp);
        break;
    case SEEK_END:
        fseeko(fp, 0, SEEK_END);
        pos = ftello(fp);
        break;
    }
    pos = (off64_t)(pos + offs);
    fseeko(fp, pos, SEEK_SET);
    if (pos == ftello(fp))
        return (tsize_t)pos;
#else
    off_t pos = 0;
    if (!cookie || !fp)
        return (tsize_t)-1;
    switch (whence) {
    case SEEK_SET:
        pos = 0;
        break;
    case SEEK_CUR:
        pos = ftell(fp);
        break;
    case SEEK_END:
        fseek(fp, 0, SEEK_END);
        pos = ftell(fp);
        break;
    }
    pos = (off_t)(pos + offs);
    fseek(fp, pos, SEEK_SET);
    if (pos == ftell(fp))
        return (tsize_t)pos;
#endif
    return (tsize_t)-1;
}
 
static int
lept_close_proc(thandle_t  cookie)
{
    FILE* fp = (FILE *)cookie;
    if (!cookie || !fp)
        return 0;
    fseek(fp, 0, SEEK_SET);
    return 0;
}
 
static toff_t
lept_size_proc(thandle_t  cookie)
{
    FILE* fp = (FILE *)cookie;
#if defined(_MSC_VER)
    __int64 pos;
    __int64 size;
    if (!cookie || !fp)
        return (tsize_t)-1;
    pos = _ftelli64(fp);
    _fseeki64(fp, 0, SEEK_END);
    size = _ftelli64(fp);
    _fseeki64(fp, pos, SEEK_SET);
#elif defined(_LARGEFILE64_SOURCE)
    off64_t pos;
    off64_t size;
    if (!fp)
        return (tsize_t)-1;
    pos = ftello(fp);
    fseeko(fp, 0, SEEK_END);
    size = ftello(fp);
    fseeko(fp, pos, SEEK_SET);
#else
    off_t pos;
    off_t size;
    if (!cookie || !fp)
        return (tsize_t)-1;
    pos = ftell(fp);
    fseek(fp, 0, SEEK_END);
    size = ftell(fp);
    fseek(fp, pos, SEEK_SET);
#endif
    return (toff_t)size;
}
 
 
/*--------------------------------------------------------------*
 *                      Reading from file                       *
 *--------------------------------------------------------------*/
PIX *
pixReadTiff(const char  *filename,
            l_int32      n)
{
FILE  *fp;
PIX   *pix;
 
    PROCNAME("pixReadTiff");
 
    if (!filename)
        return (PIX *)ERROR_PTR("filename not defined", procName, NULL);
 
    if ((fp = fopenReadStream(filename)) == NULL)
        return (PIX *)ERROR_PTR("image file not found", procName, NULL);
    pix = pixReadStreamTiff(fp, n);
    fclose(fp);
    return pix;
}
 
 
/*--------------------------------------------------------------*
 *                     Reading from stream                      *
 *--------------------------------------------------------------*/
PIX *
pixReadStreamTiff(FILE    *fp,
                  l_int32  n)
{
PIX   *pix;
TIFF  *tif;
 
    PROCNAME("pixReadStreamTiff");
 
    if (!fp)
        return (PIX *)ERROR_PTR("stream not defined", procName, NULL);
 
    if ((tif = fopenTiff(fp, "r")) == NULL)
        return (PIX *)ERROR_PTR("tif not opened", procName, NULL);
 
    if (TIFFSetDirectory(tif, n) == 0) {
        TIFFCleanup(tif);
        return NULL;
    }
    if ((pix = pixReadFromTiffStream(tif)) == NULL) {
        TIFFCleanup(tif);
        return NULL;
    }
    TIFFCleanup(tif);
    return pix;
}
 
 
static PIX *
pixReadFromTiffStream(TIFF  *tif)
{
char      *text;
l_uint8   *linebuf, *data, *rowptr;
l_uint16   spp, bps, photometry, tiffcomp, orientation, sample_fmt;
l_uint16  *redmap, *greenmap, *bluemap;
l_int32    d, wpl, bpl, comptype, i, j, k, ncolors, rval, gval, bval, aval;
l_int32    xres, yres, tiffbpl, packedbpl, half_size, twothirds_size;
l_uint32   w, h, tiffword, read_oriented;
l_uint32  *line, *ppixel, *tiffdata, *pixdata;
PIX       *pix, *pix1;
PIXCMAP   *cmap;
 
    PROCNAME("pixReadFromTiffStream");
 
    if (!tif)
        return (PIX *)ERROR_PTR("tif not defined", procName, NULL);
 
    read_oriented = 0;
 
        /* Only accept uint image data:
         *   SAMPLEFORMAT_UINT = 1;
         *   SAMPLEFORMAT_INT = 2;
         *   SAMPLEFORMAT_IEEEFP = 3;
         *   SAMPLEFORMAT_VOID = 4;   */
    TIFFGetFieldDefaulted(tif, TIFFTAG_SAMPLEFORMAT, &sample_fmt);
    if (sample_fmt != SAMPLEFORMAT_UINT) {
        L_ERROR("sample format = %d is not uint\n", procName, sample_fmt);
        return NULL;
    }
 
        /* Can't read tiff in tiled format. For what is involved, see, e.g:
         *   https://www.cs.rochester.edu/~nelson/courses/vision/\
         *     resources/tiff/libtiff.html#Tiles
         * A tiled tiff can be converted to a normal (strip) tif:
         *   tiffcp -s <input-tiled-tif> <output-strip-tif>    */
    if (TIFFIsTiled(tif)) {
        L_ERROR("tiled format is not supported\n", procName);
        return NULL;
    }
 
        /* Old style jpeg is not supported.  We tried supporting 8 bpp.
         * TIFFReadScanline() fails on this format, so we used RGBA
         * reading, which generates a 4 spp image, and pulled out the
         * red component.  However, there were problems with double-frees
         * in cleanup.  For RGB, tiffbpl is exactly half the size that
         * you would expect for the raster data in a scanline, which
         * is 3 * w.  */
    TIFFGetFieldDefaulted(tif, TIFFTAG_COMPRESSION, &tiffcomp);
    if (tiffcomp == COMPRESSION_OJPEG) {
        L_ERROR("old style jpeg format is not supported\n", procName);
        return NULL;
    }
 
        /* webp in tiff is in 4.1.0 and not yet supported in Adobe registry */
#if defined(COMPRESSION_WEBP)
    if (tiffcomp == COMPRESSION_WEBP) {
        L_ERROR("webp in tiff not generally supported yet\n", procName);
        return NULL;
    }
#endif  /* COMPRESSION_WEBP */
 
        /* Use default fields for bps and spp */
    TIFFGetFieldDefaulted(tif, TIFFTAG_BITSPERSAMPLE, &bps);
    TIFFGetFieldDefaulted(tif, TIFFTAG_SAMPLESPERPIXEL, &spp);
    if (bps != 1 && bps != 2 && bps != 4 && bps != 8 && bps != 16) {
        L_ERROR("invalid bps = %d\n", procName, bps);
        return NULL;
    }
    if (spp == 2 && bps != 8) {
        L_WARNING("for 2 spp, only handle 8 bps\n", procName);
        return NULL;
    }
    if (spp == 1) {
        d = bps;
    } else if (spp == 2) {  /* gray plus alpha */
        d = 32;  /* will convert to RGBA */
    } else if (spp == 3 || spp == 4) {
        d = 32;
    } else {
        L_ERROR("spp = %d; not in {1,2,3,4}\n", procName, spp);
        return NULL;
    }
 
    TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &w);
    TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &h);
    if (w > MaxTiffWidth) {
        L_ERROR("width = %d pixels; too large\n", procName, w);
        return NULL;
    }
    if (h > MaxTiffHeight) {
        L_ERROR("height = %d pixels; too large\n", procName, h);
        return NULL;
    }
 
        /* The relation between the size of a byte buffer required to hold
           a raster of image pixels (packedbpl) and the size of the tiff
           buffer (tiffbuf) is either 1:1 or approximately 1.5:1 or 2:1,
           depending on how the data is stored and subsampled.  For security,
           we test this relation between tiffbuf and the image parameters
           w, spp and bps. */
    tiffbpl = TIFFScanlineSize(tif);
    packedbpl = (bps * spp * w + 7) / 8;
    half_size = (L_ABS(2 * tiffbpl - packedbpl) <= 8);
    twothirds_size = (L_ABS(3 * tiffbpl - 2 * packedbpl) <= 8);
#if 0
    if (half_size)
        L_INFO("half_size: packedbpl = %d is approx. twice tiffbpl = %d\n",
               procName, packedbpl, tiffbpl);
    if (twothirds_size)
        L_INFO("twothirds_size: packedbpl = %d is approx. 1.5 tiffbpl = %d\n",
               procName, packedbpl, tiffbpl);
    lept_stderr("tiffbpl = %d, packedbpl = %d, bps = %d, spp = %d, w = %d\n",
                tiffbpl, packedbpl, bps, spp, w);
#endif
    if (tiffbpl != packedbpl && !half_size && !twothirds_size) {
        L_ERROR("invalid tiffbpl: tiffbpl = %d, packedbpl = %d, "
                "bps = %d, spp = %d, w = %d\n",
                procName, tiffbpl, packedbpl, bps, spp, w);
        return NULL;
    }
 
        /* Use a linebuf that will hold all the pixels generated
           by tiff when reading (decompressing) a scanline. */
    if ((pix = pixCreate(w, h, d)) == NULL)
        return (PIX *)ERROR_PTR("pix not made", procName, NULL);
    pixSetInputFormat(pix, IFF_TIFF);
    data = (l_uint8 *)pixGetData(pix);
    wpl = pixGetWpl(pix);
    bpl = 4 * wpl;
    if (spp == 1) {
        linebuf = (l_uint8 *)LEPT_CALLOC(4 * wpl, sizeof(l_uint8));
        for (i = 0; i < h; i++) {
            if (TIFFReadScanline(tif, linebuf, i, 0) < 0) {
                LEPT_FREE(linebuf);
                pixDestroy(&pix);
                L_ERROR("spp = 1, read fail at line %d\n", procName, i);
                return NULL;
            }
            memcpy(data, linebuf, tiffbpl);
            data += bpl;
        }
        if (bps <= 8)
            pixEndianByteSwap(pix);
        else   /* bps == 16 */
            pixEndianTwoByteSwap(pix);
        LEPT_FREE(linebuf);
    } else if (spp == 2 && bps == 8) {  /* gray plus alpha */
        L_INFO("gray+alpha is not supported; converting to RGBA\n", procName);
        pixSetSpp(pix, 4);
        linebuf = (l_uint8 *)LEPT_CALLOC(4 * wpl, sizeof(l_uint8));
        pixdata = pixGetData(pix);
        for (i = 0; i < h; i++) {
            if (TIFFReadScanline(tif, linebuf, i, 0) < 0) {
                LEPT_FREE(linebuf);
                pixDestroy(&pix);
                L_ERROR("spp = 2, read fail at line %d\n", procName, i);
                return NULL;
            }
            rowptr = linebuf;
            ppixel = pixdata + i * wpl;
            for (j = k = 0; j < w; j++) {
                    /* Copy gray value into r, g and b */
                SET_DATA_BYTE(ppixel, COLOR_RED, rowptr[k]);
                SET_DATA_BYTE(ppixel, COLOR_GREEN, rowptr[k]);
                SET_DATA_BYTE(ppixel, COLOR_BLUE, rowptr[k++]);
                SET_DATA_BYTE(ppixel, L_ALPHA_CHANNEL, rowptr[k++]);
                ppixel++;
            }
        }
        LEPT_FREE(linebuf);
    } else {  /* rgb and rgba */
        if ((tiffdata = (l_uint32 *)LEPT_CALLOC((size_t)w * h,
                                                 sizeof(l_uint32))) == NULL) {
            pixDestroy(&pix);
            return (PIX *)ERROR_PTR("calloc fail for tiffdata", procName, NULL);
        }
            /* TIFFReadRGBAImageOriented() converts to 8 bps */
        if (!TIFFReadRGBAImageOriented(tif, w, h, tiffdata,
                                       ORIENTATION_TOPLEFT, 0)) {
            LEPT_FREE(tiffdata);
            pixDestroy(&pix);
            return (PIX *)ERROR_PTR("failed to read tiffdata", procName, NULL);
        } else {
            read_oriented = 1;
        }
 
        if (spp == 4) pixSetSpp(pix, 4);
        line = pixGetData(pix);
        for (i = 0; i < h; i++, line += wpl) {
            for (j = 0, ppixel = line; j < w; j++) {
                    /* TIFFGet* are macros */
                tiffword = tiffdata[i * w + j];
                rval = TIFFGetR(tiffword);
                gval = TIFFGetG(tiffword);
                bval = TIFFGetB(tiffword);
                if (spp == 3) {
                    composeRGBPixel(rval, gval, bval, ppixel);
                } else {  /* spp == 4 */
                    aval = TIFFGetA(tiffword);
                    composeRGBAPixel(rval, gval, bval, aval, ppixel);
                }
                ppixel++;
            }
        }
        LEPT_FREE(tiffdata);
    }
 
    if (getTiffStreamResolution(tif, &xres, &yres) == 0) {
        pixSetXRes(pix, xres);
        pixSetYRes(pix, yres);
    }
 
        /* Find and save the compression type */
    comptype = getTiffCompressedFormat(tiffcomp);
    pixSetInputFormat(pix, comptype);
 
    if (TIFFGetField(tif, TIFFTAG_COLORMAP, &redmap, &greenmap, &bluemap)) {
            /* Save the colormap as a pix cmap.  Because the
             * tiff colormap components are 16 bit unsigned,
             * and go from black (0) to white (0xffff), the
             * the pix cmap takes the most significant byte. */
        if (bps > 8) {
            pixDestroy(&pix);
            return (PIX *)ERROR_PTR("colormap size > 256", procName, NULL);
        }
        if ((cmap = pixcmapCreate(bps)) == NULL) {
            pixDestroy(&pix);
            return (PIX *)ERROR_PTR("colormap not made", procName, NULL);
        }
        ncolors = 1 << bps;
        for (i = 0; i < ncolors; i++)
            pixcmapAddColor(cmap, redmap[i] >> 8, greenmap[i] >> 8,
                            bluemap[i] >> 8);
        if (pixSetColormap(pix, cmap)) {
            pixDestroy(&pix);
            return (PIX *)ERROR_PTR("invalid colormap", procName, NULL);
        }
 
            /* Remove the colormap for 1 bpp. */
        if (bps == 1) {
            pix1 = pixRemoveColormap(pix, REMOVE_CMAP_BASED_ON_SRC);
            pixDestroy(&pix);
            pix = pix1;
        }
    } else {   /* No colormap: check photometry and invert if necessary */
        if (!TIFFGetField(tif, TIFFTAG_PHOTOMETRIC, &photometry)) {
                /* Guess default photometry setting.  Assume min_is_white
                 * if compressed 1 bpp; min_is_black otherwise. */
            if (tiffcomp == COMPRESSION_CCITTFAX3 ||
                tiffcomp == COMPRESSION_CCITTFAX4 ||
                tiffcomp == COMPRESSION_CCITTRLE ||
                tiffcomp == COMPRESSION_CCITTRLEW) {
                photometry = PHOTOMETRIC_MINISWHITE;
            } else {
                photometry = PHOTOMETRIC_MINISBLACK;
            }
        }
        if ((d == 1 && photometry == PHOTOMETRIC_MINISBLACK) ||
            (d == 8 && photometry == PHOTOMETRIC_MINISWHITE))
            pixInvert(pix, pix);
    }
 
    if (TIFFGetField(tif, TIFFTAG_ORIENTATION, &orientation)) {
        if (orientation >= 1 && orientation <= 8) {
            struct tiff_transform *transform = (read_oriented) ?
                &tiff_partial_orientation_transforms[orientation - 1] :
                &tiff_orientation_transforms[orientation - 1];
            if (transform->vflip) pixFlipTB(pix, pix);
            if (transform->hflip) pixFlipLR(pix, pix);
            if (transform->rotate) {
                PIX *oldpix = pix;
                pix = pixRotate90(oldpix, transform->rotate);
                pixDestroy(&oldpix);
            }
        }
    }
 
    text = NULL;
    TIFFGetField(tif, TIFFTAG_IMAGEDESCRIPTION, &text);
    if (text) pixSetText(pix, text);
    return pix;
}
 
 
/*--------------------------------------------------------------*
 *                       Writing to file                        *
 *--------------------------------------------------------------*/
l_ok
pixWriteTiff(const char  *filename,
             PIX         *pix,
             l_int32      comptype,
             const char  *modestr)
{
    return pixWriteTiffCustom(filename, pix, comptype, modestr,
                              NULL, NULL, NULL, NULL);
}
 
 
l_ok
pixWriteTiffCustom(const char  *filename,
                   PIX         *pix,
                   l_int32      comptype,
                   const char  *modestr,
                   NUMA        *natags,
                   SARRAY      *savals,
                   SARRAY      *satypes,
                   NUMA        *nasizes)
{
l_int32  ret;
TIFF    *tif;
 
    PROCNAME("pixWriteTiffCustom");
 
    if (!filename)
        return ERROR_INT("filename not defined", procName, 1);
    if (!pix)
        return ERROR_INT("pix not defined", procName, 1);
 
    if ((tif = openTiff(filename, modestr)) == NULL)
        return ERROR_INT("tif not opened", procName, 1);
    ret = pixWriteToTiffStream(tif, pix, comptype, natags, savals,
                               satypes, nasizes);
    TIFFClose(tif);
    return ret;
}
 
 
/*--------------------------------------------------------------*
 *                       Writing to stream                      *
 *--------------------------------------------------------------*/
l_ok
pixWriteStreamTiff(FILE    *fp,
                   PIX     *pix,
                   l_int32  comptype)
{
    return pixWriteStreamTiffWA(fp, pix, comptype, "w");
}
 
 
l_ok
pixWriteStreamTiffWA(FILE        *fp,
                     PIX         *pix,
                     l_int32      comptype,
                     const char  *modestr)
{
TIFF  *tif;
 
    PROCNAME("pixWriteStreamTiffWA");
 
    if (!fp)
        return ERROR_INT("stream not defined", procName, 1 );
    if (!pix)
        return ERROR_INT("pix not defined", procName, 1 );
    if (strcmp(modestr, "w") && strcmp(modestr, "a")) {
        L_ERROR("modestr = %s; not 'w' or 'a'\n", procName, modestr);
        return 1;
    }
 
    if (pixGetDepth(pix) != 1 && comptype != IFF_TIFF &&
        comptype != IFF_TIFF_LZW && comptype != IFF_TIFF_ZIP &&
        comptype != IFF_TIFF_JPEG) {
        L_WARNING("invalid compression type %d for bpp > 1; using TIFF_ZIP\n",
                  procName, comptype);
        comptype = IFF_TIFF_ZIP;
    }
 
    if ((tif = fopenTiff(fp, modestr)) == NULL)
        return ERROR_INT("tif not opened", procName, 1);
 
    if (pixWriteToTiffStream(tif, pix, comptype, NULL, NULL, NULL, NULL)) {
        TIFFCleanup(tif);
        return ERROR_INT("tif write error", procName, 1);
    }
 
    TIFFCleanup(tif);
    return 0;
}
 
 
static l_int32
pixWriteToTiffStream(TIFF    *tif,
                     PIX     *pix,
                     l_int32  comptype,
                     NUMA    *natags,
                     SARRAY  *savals,
                     SARRAY  *satypes,
                     NUMA    *nasizes)
{
l_uint8   *linebuf, *data;
l_uint16   redmap[256], greenmap[256], bluemap[256];
l_int32    w, h, d, spp, i, j, k, wpl, bpl, tiffbpl, ncolors, cmapsize;
l_int32   *rmap, *gmap, *bmap;
l_int32    xres, yres;
l_uint32  *line, *ppixel;
PIX       *pixt;
PIXCMAP   *cmap;
char      *text;
 
    PROCNAME("pixWriteToTiffStream");
 
    if (!tif)
        return ERROR_INT("tif stream not defined", procName, 1);
    if (!pix)
        return ERROR_INT( "pix not defined", procName, 1 );
 
    pixSetPadBits(pix, 0);
    pixGetDimensions(pix, &w, &h, &d);
    spp = pixGetSpp(pix);
    xres = pixGetXRes(pix);
    yres = pixGetYRes(pix);
    if (xres == 0) xres = DefaultResolution;
    if (yres == 0) yres = DefaultResolution;
 
        /* ------------------ Write out the header -------------  */
    TIFFSetField(tif, TIFFTAG_RESOLUTIONUNIT, (l_uint32)RESUNIT_INCH);
    TIFFSetField(tif, TIFFTAG_XRESOLUTION, (l_float64)xres);
    TIFFSetField(tif, TIFFTAG_YRESOLUTION, (l_float64)yres);
 
    TIFFSetField(tif, TIFFTAG_IMAGEWIDTH, (l_uint32)w);
    TIFFSetField(tif, TIFFTAG_IMAGELENGTH, (l_uint32)h);
    TIFFSetField(tif, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
 
    if ((text = pixGetText(pix)) != NULL)
        TIFFSetField(tif, TIFFTAG_IMAGEDESCRIPTION, text);
 
    if (d == 1 && !pixGetColormap(pix)) {
            /* If d == 1, preserve the colormap.  Note that when
             * d == 1 pix with colormaps are read, the colormaps
             * are removed.  The only pix in leptonica that have
             * colormaps are made programmatically. */
        TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_MINISWHITE);
    } else if ((d == 32 && spp == 3) || d == 24) {
        TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_RGB);
        TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, (l_uint16)3);
        TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE,
                       (l_uint16)8, (l_uint16)8, (l_uint16)8);
    } else if (d == 32 && spp == 4) {
        l_uint16  val[1];
        val[0] = EXTRASAMPLE_ASSOCALPHA;
        TIFFSetField(tif, TIFFTAG_EXTRASAMPLES, (l_uint16)1, &val);
        TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_RGB);
        TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, (l_uint16)4);
        TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE,
                     (l_uint16)8, (l_uint16)8, (l_uint16)8, (l_uint16)8);
    } else if (d == 16) {  /* we only support spp = 1, bps = 16 */
        TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_MINISBLACK);
    } else if ((cmap = pixGetColormap(pix)) == NULL) {
        TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_MINISBLACK);
    } else {  /* Save colormap in the tiff; not more than 256 colors */
        if (d > 8) {
            L_ERROR("d = %d > 8 with colormap!; reducing to 8\n", procName, d);
            d = 8;
        }
        pixcmapToArrays(cmap, &rmap, &gmap, &bmap, NULL);
        ncolors = pixcmapGetCount(cmap);
        ncolors = L_MIN(256, ncolors);  /* max 256 */
        cmapsize = 1 << d;
        cmapsize = L_MIN(256, cmapsize);  /* power of 2; max 256 */
        if (ncolors > cmapsize) {
            L_WARNING("too many colors in cmap for tiff; truncating\n",
                      procName);
            ncolors = cmapsize;
        }
        for (i = 0; i < ncolors; i++) {
            redmap[i] = (rmap[i] << 8) | rmap[i];
            greenmap[i] = (gmap[i] << 8) | gmap[i];
            bluemap[i] = (bmap[i] << 8) | bmap[i];
        }
        for (i = ncolors; i < cmapsize; i++)  /* init, even though not used */
            redmap[i] = greenmap[i] = bluemap[i] = 0;
        LEPT_FREE(rmap);
        LEPT_FREE(gmap);
        LEPT_FREE(bmap);
 
        TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_PALETTE);
        TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, (l_uint16)1);
        TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, (l_uint16)d);
        TIFFSetField(tif, TIFFTAG_COLORMAP, redmap, greenmap, bluemap);
    }
 
    if (d <= 16) {
        TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, (l_uint16)d);
        TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, (l_uint16)1);
    }
 
    TIFFSetField(tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
    if (comptype == IFF_TIFF) {  /* no compression */
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_NONE);
    } else if (comptype == IFF_TIFF_G4) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_CCITTFAX4);
    } else if (comptype == IFF_TIFF_G3) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_CCITTFAX3);
    } else if (comptype == IFF_TIFF_RLE) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_CCITTRLE);
    } else if (comptype == IFF_TIFF_PACKBITS) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_PACKBITS);
    } else if (comptype == IFF_TIFF_LZW) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_LZW);
    } else if (comptype == IFF_TIFF_ZIP) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_ADOBE_DEFLATE);
    } else if (comptype == IFF_TIFF_JPEG) {
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_JPEG);
    } else {
        L_WARNING("unknown tiff compression; using none\n", procName);
        TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_NONE);
    }
 
        /* This is a no-op if arrays are NULL */
    writeCustomTiffTags(tif, natags, savals, satypes, nasizes);
 
        /* ------------- Write out the image data -------------  */
    tiffbpl = TIFFScanlineSize(tif);
    wpl = pixGetWpl(pix);
    bpl = 4 * wpl;
    if (tiffbpl > bpl)
        lept_stderr("Big trouble: tiffbpl = %d, bpl = %d\n", tiffbpl, bpl);
    if ((linebuf = (l_uint8 *)LEPT_CALLOC(1, bpl)) == NULL)
        return ERROR_INT("calloc fail for linebuf", procName, 1);
 
        /* Use single strip for image */
    TIFFSetField(tif, TIFFTAG_ROWSPERSTRIP, h);
 
    if (d != 24 && d != 32) {
        if (d == 16)
            pixt = pixEndianTwoByteSwapNew(pix);
        else
            pixt = pixEndianByteSwapNew(pix);
        data = (l_uint8 *)pixGetData(pixt);
        for (i = 0; i < h; i++, data += bpl) {
            memcpy(linebuf, data, tiffbpl);
            if (TIFFWriteScanline(tif, linebuf, i, 0) < 0)
                break;
        }
        pixDestroy(&pixt);
    } else if (d == 24) {  /* See note 4 above: special case of 24 bpp rgb */
        for (i = 0; i < h; i++) {
            line = pixGetData(pix) + i * wpl;
            if (TIFFWriteScanline(tif, (l_uint8 *)line, i, 0) < 0)
                break;
        }
    } else {  /* 32 bpp rgb or rgba */
        for (i = 0; i < h; i++) {
            line = pixGetData(pix) + i * wpl;
            for (j = 0, k = 0, ppixel = line; j < w; j++) {
                linebuf[k++] = GET_DATA_BYTE(ppixel, COLOR_RED);
                linebuf[k++] = GET_DATA_BYTE(ppixel, COLOR_GREEN);
                linebuf[k++] = GET_DATA_BYTE(ppixel, COLOR_BLUE);
                if (spp == 4)
                    linebuf[k++] = GET_DATA_BYTE(ppixel, L_ALPHA_CHANNEL);
                ppixel++;
            }
            if (TIFFWriteScanline(tif, linebuf, i, 0) < 0)
                break;
        }
    }
 
/*    TIFFWriteDirectory(tif); */
    LEPT_FREE(linebuf);
 
    return 0;
}
 
 
static l_int32
writeCustomTiffTags(TIFF    *tif,
                    NUMA    *natags,
                    SARRAY  *savals,
                    SARRAY  *satypes,
                    NUMA    *nasizes)
{
char      *sval, *type;
l_int32    i, n, ns, size, tagval, val;
l_float64  dval;
l_uint32   uval, uval2;
 
    PROCNAME("writeCustomTiffTags");
 
    if (!tif)
        return ERROR_INT("tif stream not defined", procName, 1);
    if (!natags && !savals && !satypes)
        return 0;
    if (!natags || !savals || !satypes)
        return ERROR_INT("not all arrays defined", procName, 1);
    n = numaGetCount(natags);
    if ((sarrayGetCount(savals) != n) || (sarrayGetCount(satypes) != n))
        return ERROR_INT("not all sa the same size", procName, 1);
 
        /* The sized arrays (4 args to TIFFSetField) are written first */
    if (nasizes) {
        ns = numaGetCount(nasizes);
        if (ns > n)
            return ERROR_INT("too many 4-arg tag calls", procName, 1);
        for (i = 0; i < ns; i++) {
            numaGetIValue(natags, i, &tagval);
            sval = sarrayGetString(savals, i, L_NOCOPY);
            type = sarrayGetString(satypes, i, L_NOCOPY);
            numaGetIValue(nasizes, i, &size);
            if (strcmp(type, "char*") && strcmp(type, "l_uint8*"))
                L_WARNING("array type not char* or l_uint8*; ignore\n",
                          procName);
            TIFFSetField(tif, tagval, size, sval);
        }
    } else {
        ns = 0;
    }
 
        /* The typical tags (3 args to TIFFSetField) are now written */
    for (i = ns; i < n; i++) {
        numaGetIValue(natags, i, &tagval);
        sval = sarrayGetString(savals, i, L_NOCOPY);
        type = sarrayGetString(satypes, i, L_NOCOPY);
        if (!strcmp(type, "char*") || !strcmp(type, "const char*")) {
            TIFFSetField(tif, tagval, sval);
        } else if (!strcmp(type, "l_uint16")) {
            if (sscanf(sval, "%u", &uval) == 1) {
                TIFFSetField(tif, tagval, (l_uint16)uval);
            } else {
                lept_stderr("val %s not of type %s\n", sval, type);
                return ERROR_INT("custom tag(s) not written", procName, 1);
            }
        } else if (!strcmp(type, "l_uint32")) {
            if (sscanf(sval, "%u", &uval) == 1) {
                TIFFSetField(tif, tagval, uval);
            } else {
                lept_stderr("val %s not of type %s\n", sval, type);
                return ERROR_INT("custom tag(s) not written", procName, 1);
            }
        } else if (!strcmp(type, "l_int32")) {
            if (sscanf(sval, "%d", &val) == 1) {
                TIFFSetField(tif, tagval, val);
            } else {
                lept_stderr("val %s not of type %s\n", sval, type);
                return ERROR_INT("custom tag(s) not written", procName, 1);
            }
        } else if (!strcmp(type, "l_float64")) {
            if (sscanf(sval, "%lf", &dval) == 1) {
                TIFFSetField(tif, tagval, dval);
            } else {
                lept_stderr("val %s not of type %s\n", sval, type);
                return ERROR_INT("custom tag(s) not written", procName, 1);
            }
        } else if (!strcmp(type, "l_uint16-l_uint16")) {
            if (sscanf(sval, "%u-%u", &uval, &uval2) == 2) {
                TIFFSetField(tif, tagval, (l_uint16)uval, (l_uint16)uval2);
            } else {
                lept_stderr("val %s not of type %s\n", sval, type);
                return ERROR_INT("custom tag(s) not written", procName, 1);
            }
        } else {
            lept_stderr("unknown type %s\n",type);
            return ERROR_INT("unknown type; tag(s) not written", procName, 1);
        }
    }
    return 0;
}
 
 
/*--------------------------------------------------------------*
 *               Reading and writing multipage tiff             *
 *--------------------------------------------------------------*/
PIX *
pixReadFromMultipageTiff(const char  *fname,
                         size_t      *poffset)
{
l_int32  retval;
size_t   offset;
PIX     *pix;
TIFF    *tif;
 
    PROCNAME("pixReadFromMultipageTiff");
 
    if (!fname)
        return (PIX *)ERROR_PTR("fname not defined", procName, NULL);
    if (!poffset)
        return (PIX *)ERROR_PTR("&offset not defined", procName, NULL);
 
    if ((tif = openTiff(fname, "r")) == NULL) {
        L_ERROR("tif open failed for %s\n", procName, fname);
        return NULL;
    }
 
        /* Set ptrs in the TIFF to the beginning of the image */
    offset = *poffset;
    retval = (offset == 0) ? TIFFSetDirectory(tif, 0)
                            : TIFFSetSubDirectory(tif, offset);
    if (retval == 0) {
        TIFFClose(tif);
        return NULL;
    }
 
    if ((pix = pixReadFromTiffStream(tif)) == NULL) {
        TIFFClose(tif);
        return NULL;
    }
 
        /* Advance to the next image and return the new offset */
    TIFFReadDirectory(tif);
    *poffset = TIFFCurrentDirOffset(tif);
    TIFFClose(tif);
    return pix;
}
 
 
PIXA *
pixaReadMultipageTiff(const char  *filename)
{
l_int32  i, npages;
FILE    *fp;
PIX     *pix;
PIXA    *pixa;
TIFF    *tif;
 
    PROCNAME("pixaReadMultipageTiff");
 
    if (!filename)
        return (PIXA *)ERROR_PTR("filename not defined", procName, NULL);
 
    if ((fp = fopenReadStream(filename)) == NULL)
        return (PIXA *)ERROR_PTR("stream not opened", procName, NULL);
    if (fileFormatIsTiff(fp)) {
        tiffGetCount(fp, &npages);
        L_INFO(" Tiff: %d pages\n", procName, npages);
    } else {
        return (PIXA *)ERROR_PTR("file not tiff", procName, NULL);
    }
 
    if ((tif = fopenTiff(fp, "r")) == NULL)
        return (PIXA *)ERROR_PTR("tif not opened", procName, NULL);
 
    pixa = pixaCreate(npages);
    pix = NULL;
    for (i = 0; i < npages; i++) {
        if ((pix = pixReadFromTiffStream(tif)) != NULL) {
            pixaAddPix(pixa, pix, L_INSERT);
        } else {
            L_WARNING("pix not read for page %d\n", procName, i);
        }
 
            /* Advance to the next directory (i.e., the next image) */
        if (TIFFReadDirectory(tif) == 0)
            break;
    }
 
    fclose(fp);
    TIFFCleanup(tif);
    return pixa;
}
 
 
l_ok
pixaWriteMultipageTiff(const char  *fname,
                       PIXA        *pixa)
{
const char  *modestr;
l_int32      i, n;
PIX         *pix1;
 
    PROCNAME("pixaWriteMultipageTiff");
 
    if (!fname)
        return ERROR_INT("fname not defined", procName, 1);
    if (!pixa)
        return ERROR_INT("pixa not defined", procName, 1);
 
    n = pixaGetCount(pixa);
    for (i = 0; i < n; i++) {
        modestr = (i == 0) ? "w" : "a";
        pix1 = pixaGetPix(pixa, i, L_CLONE);
        if (pixGetDepth(pix1) == 1)
            pixWriteTiff(fname, pix1, IFF_TIFF_G4, modestr);
        else
            pixWriteTiff(fname, pix1, IFF_TIFF_ZIP, modestr);
        pixDestroy(&pix1);
    }
 
    return 0;
}
 
 
l_ok
writeMultipageTiff(const char  *dirin,
                   const char  *substr,
                   const char  *fileout)
{
SARRAY  *sa;
 
    PROCNAME("writeMultipageTiff");
 
    if (!dirin)
        return ERROR_INT("dirin not defined", procName, 1);
    if (!fileout)
        return ERROR_INT("fileout not defined", procName, 1);
 
        /* Get all filtered and sorted full pathnames. */
    sa = getSortedPathnamesInDirectory(dirin, substr, 0, 0);
 
        /* Generate the tiff file */
    writeMultipageTiffSA(sa, fileout);
    sarrayDestroy(&sa);
    return 0;
}
 
 
l_ok
writeMultipageTiffSA(SARRAY      *sa,
                     const char  *fileout)
{
char        *fname;
const char  *op;
l_int32      i, nfiles, firstfile, format;
PIX         *pix;
 
    PROCNAME("writeMultipageTiffSA");
 
    if (!sa)
        return ERROR_INT("sa not defined", procName, 1);
    if (!fileout)
        return ERROR_INT("fileout not defined", procName, 1);
 
    nfiles = sarrayGetCount(sa);
    firstfile = TRUE;
    for (i = 0; i < nfiles; i++) {
        op = (firstfile) ? "w" : "a";
        fname = sarrayGetString(sa, i, L_NOCOPY);
        findFileFormat(fname, &format);
        if (format == IFF_UNKNOWN) {
            L_INFO("format of %s not known\n", procName, fname);
            continue;
        }
 
        if ((pix = pixRead(fname)) == NULL) {
            L_WARNING("pix not made for file: %s\n", procName, fname);
            continue;
        }
        if (pixGetDepth(pix) == 1)
            pixWriteTiff(fileout, pix, IFF_TIFF_G4, op);
        else
            pixWriteTiff(fileout, pix, IFF_TIFF_ZIP, op);
        firstfile = FALSE;
        pixDestroy(&pix);
    }
 
    return 0;
}
 
 
/*--------------------------------------------------------------*
 *                    Print info to stream                      *
 *--------------------------------------------------------------*/
l_ok
fprintTiffInfo(FILE        *fpout,
               const char  *tiffile)
{
TIFF  *tif;
 
    PROCNAME("fprintTiffInfo");
 
    if (!tiffile)
        return ERROR_INT("tiffile not defined", procName, 1);
    if (!fpout)
        return ERROR_INT("stream out not defined", procName, 1);
 
    if ((tif = openTiff(tiffile, "rb")) == NULL)
        return ERROR_INT("tif not open for read", procName, 1);
 
    TIFFPrintDirectory(tif, fpout, 0);
    TIFFClose(tif);
 
    return 0;
}
 
 
/*--------------------------------------------------------------*
 *                        Get page count                        *
 *--------------------------------------------------------------*/
l_ok
tiffGetCount(FILE     *fp,
             l_int32  *pn)
{
l_int32  i;
TIFF    *tif;
 
    PROCNAME("tiffGetCount");
 
    if (!fp)
        return ERROR_INT("stream not defined", procName, 1);
    if (!pn)
        return ERROR_INT("&n not defined", procName, 1);
    *pn = 0;
 
    if ((tif = fopenTiff(fp, "r")) == NULL)
        return ERROR_INT("tif not open for read", procName, 1);
 
    for (i = 1; ; i++) {
        if (TIFFReadDirectory(tif) == 0)
            break;
        if (i == ManyPagesInTiffFile + 1) {
            L_WARNING("big file: more than %d pages\n", procName,
                      ManyPagesInTiffFile);
        }
    }
    *pn = i;
    TIFFCleanup(tif);
    return 0;
}
 
 
/*--------------------------------------------------------------*
 *                   Get resolution from tif                    *
 *--------------------------------------------------------------*/
l_ok
getTiffResolution(FILE     *fp,
                  l_int32  *pxres,
                  l_int32  *pyres)
{
TIFF  *tif;
 
    PROCNAME("getTiffResolution");
 
    if (!pxres || !pyres)
        return ERROR_INT("&xres and &yres not both defined", procName, 1);
    *pxres = *pyres = 0;
    if (!fp)
        return ERROR_INT("stream not opened", procName, 1);
 
    if ((tif = fopenTiff(fp, "r")) == NULL)
        return ERROR_INT("tif not open for read", procName, 1);
    getTiffStreamResolution(tif, pxres, pyres);
    TIFFCleanup(tif);
    return 0;
}
 
 
static l_int32
getTiffStreamResolution(TIFF     *tif,
                        l_int32  *pxres,
                        l_int32  *pyres)
{
l_uint16   resunit;
l_int32    foundxres, foundyres;
l_float32  fxres, fyres;
 
    PROCNAME("getTiffStreamResolution");
 
    if (!tif)
        return ERROR_INT("tif not opened", procName, 1);
    if (!pxres || !pyres)
        return ERROR_INT("&xres and &yres not both defined", procName, 1);
    *pxres = *pyres = 0;
 
    TIFFGetFieldDefaulted(tif, TIFFTAG_RESOLUTIONUNIT, &resunit);
    foundxres = TIFFGetField(tif, TIFFTAG_XRESOLUTION, &fxres);
    foundyres = TIFFGetField(tif, TIFFTAG_YRESOLUTION, &fyres);
    if (!foundxres && !foundyres) return 1;
    if (isnan(fxres) || isnan(fyres)) return 1;
    if (!foundxres && foundyres)
        fxres = fyres;
    else if (foundxres && !foundyres)
        fyres = fxres;
 
        /* Avoid overflow into int32; set max fxres and fyres to 5 x 10^8 */
    if (fxres < 0 || fxres > (1L << 29) || fyres < 0 || fyres > (1L << 29))
        return ERROR_INT("fxres and/or fyres values are invalid", procName, 1);
 
    if (resunit == RESUNIT_CENTIMETER) {  /* convert to ppi */
        *pxres = (l_int32)(2.54 * fxres + 0.5);
        *pyres = (l_int32)(2.54 * fyres + 0.5);
    } else {
        *pxres = (l_int32)fxres;
        *pyres = (l_int32)fyres;
    }
 
    return 0;
}
 
 
/*--------------------------------------------------------------*
 *              Get some tiff header information                *
 *--------------------------------------------------------------*/
l_ok
readHeaderTiff(const char *filename,
               l_int32     n,
               l_int32    *pw,
               l_int32    *ph,
               l_int32    *pbps,
               l_int32    *pspp,
               l_int32    *pres,
               l_int32    *pcmap,
               l_int32    *pformat)
{
l_int32  ret;
FILE    *fp;
 
    PROCNAME("readHeaderTiff");
 
    if (pw) *pw = 0;
    if (ph) *ph = 0;
    if (pbps) *pbps = 0;
    if (pspp) *pspp = 0;
    if (pres) *pres = 0;
    if (pcmap) *pcmap = 0;
    if (pformat) *pformat = 0;
    if (!filename)
        return ERROR_INT("filename not defined", procName, 1);
    if (!pw && !ph && !pbps && !pspp && !pres && !pcmap && !pformat)
        return ERROR_INT("no results requested", procName, 1);
 
    if ((fp = fopenReadStream(filename)) == NULL)
        return ERROR_INT("image file not found", procName, 1);
    ret = freadHeaderTiff(fp, n, pw, ph, pbps, pspp, pres, pcmap, pformat);
    fclose(fp);
    return ret;
}
 
 
l_ok
freadHeaderTiff(FILE     *fp,
                l_int32   n,
                l_int32  *pw,
                l_int32  *ph,
                l_int32  *pbps,
                l_int32  *pspp,
                l_int32  *pres,
                l_int32  *pcmap,
                l_int32  *pformat)
{
l_int32  i, ret, format;
TIFF    *tif;
 
    PROCNAME("freadHeaderTiff");
 
    if (pw) *pw = 0;
    if (ph) *ph = 0;
    if (pbps) *pbps = 0;
    if (pspp) *pspp = 0;
    if (pres) *pres = 0;
    if (pcmap) *pcmap = 0;
    if (pformat) *pformat = 0;
    if (!fp)
        return ERROR_INT("stream not defined", procName, 1);
    if (n < 0)
        return ERROR_INT("image index must be >= 0", procName, 1);
    if (!pw && !ph && !pbps && !pspp && !pres && !pcmap && !pformat)
        return ERROR_INT("no results requested", procName, 1);
 
    findFileFormatStream(fp, &format);
    if (!L_FORMAT_IS_TIFF(format))
        return ERROR_INT("file not tiff format", procName, 1);
 
    if ((tif = fopenTiff(fp, "r")) == NULL)
        return ERROR_INT("tif not open for read", procName, 1);
 
    for (i = 0; i < n; i++) {
        if (TIFFReadDirectory(tif) == 0)
            return ERROR_INT("image n not found in file", procName, 1);
    }
 
    ret = tiffReadHeaderTiff(tif, pw, ph, pbps, pspp, pres, pcmap, pformat);
    TIFFCleanup(tif);
    return ret;
}
 
 
l_ok
readHeaderMemTiff(const l_uint8  *cdata,
                  size_t          size,
                  l_int32         n,
                  l_int32        *pw,
                  l_int32        *ph,
                  l_int32        *pbps,
                  l_int32        *pspp,
                  l_int32        *pres,
                  l_int32        *pcmap,
                  l_int32        *pformat)
{
l_uint8  *data;
l_int32   i, ret;
TIFF     *tif;
 
    PROCNAME("readHeaderMemTiff");
 
    if (pw) *pw = 0;
    if (ph) *ph = 0;
    if (pbps) *pbps = 0;
    if (pspp) *pspp = 0;
    if (pres) *pres = 0;
    if (pcmap) *pcmap = 0;
    if (pformat) *pformat = 0;
    if (!pw && !ph && !pbps && !pspp && !pres && !pcmap && !pformat)
        return ERROR_INT("no results requested", procName, 1);
    if (!cdata)
        return ERROR_INT("cdata not defined", procName, 1);
 
        /* Open a tiff stream to memory */
    data = (l_uint8 *)cdata;  /* we're really not going to change this */
    if ((tif = fopenTiffMemstream("tifferror", "r", &data, &size)) == NULL)
        return ERROR_INT("tiff stream not opened", procName, 1);
 
    for (i = 0; i < n; i++) {
        if (TIFFReadDirectory(tif) == 0) {
            TIFFClose(tif);
            return ERROR_INT("image n not found in file", procName, 1);
        }
    }
 
    ret = tiffReadHeaderTiff(tif, pw, ph, pbps, pspp, pres, pcmap, pformat);
    TIFFClose(tif);
    return ret;
}
 
 
static l_int32
tiffReadHeaderTiff(TIFF     *tif,
                   l_int32  *pw,
                   l_int32  *ph,
                   l_int32  *pbps,
                   l_int32  *pspp,
                   l_int32  *pres,
                   l_int32  *pcmap,
                   l_int32  *pformat)
{
l_uint16   tiffcomp;
l_uint16   bps, spp;
l_uint16  *rmap, *gmap, *bmap;
l_int32    xres, yres;
l_uint32   w, h;
 
    PROCNAME("tiffReadHeaderTiff");
 
    if (!tif)
        return ERROR_INT("tif not opened", procName, 1);
 
    TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &w);
    TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &h);
    TIFFGetFieldDefaulted(tif, TIFFTAG_BITSPERSAMPLE, &bps);
    TIFFGetFieldDefaulted(tif, TIFFTAG_SAMPLESPERPIXEL, &spp);
    if (w < 1 || h < 1)
        return ERROR_INT("tif w and h not both > 0", procName, 1);
    if (bps != 1 && bps != 2 && bps != 4 && bps != 8 && bps != 16)
        return ERROR_INT("bps not in set {1,2,4,8,16}", procName, 1);
    if (spp != 1 && spp != 2 && spp != 3 && spp != 4)
        return ERROR_INT("spp not in set {1,2,3,4}", procName, 1);
    if (pw) *pw = w;
    if (ph) *ph = h;
    if (pbps) *pbps = bps;
    if (pspp) *pspp = spp;
    if (pres) {
        *pres = 300;  /* default ppi */
        if (getTiffStreamResolution(tif, &xres, &yres) == 0)
            *pres = (l_int32)xres;
    }
    if (pcmap) {
        *pcmap = 0;
        if (TIFFGetField(tif, TIFFTAG_COLORMAP, &rmap, &gmap, &bmap))
            *pcmap = 1;
    }
    if (pformat) {
        TIFFGetFieldDefaulted(tif, TIFFTAG_COMPRESSION, &tiffcomp);
        *pformat = getTiffCompressedFormat(tiffcomp);
    }
    return 0;
}
 
 
l_ok
findTiffCompression(FILE     *fp,
                    l_int32  *pcomptype)
{
l_uint16  tiffcomp;
TIFF     *tif;
 
    PROCNAME("findTiffCompression");
 
    if (!pcomptype)
        return ERROR_INT("&comptype not defined", procName, 1);
    *pcomptype = IFF_UNKNOWN;  /* init */
    if (!fp)
        return ERROR_INT("stream not defined", procName, 1);
 
    if ((tif = fopenTiff(fp, "r")) == NULL)
        return ERROR_INT("tif not opened", procName, 1);
    TIFFGetFieldDefaulted(tif, TIFFTAG_COMPRESSION, &tiffcomp);
    *pcomptype = getTiffCompressedFormat(tiffcomp);
    TIFFCleanup(tif);
    return 0;
}
 
 
static l_int32
getTiffCompressedFormat(l_uint16  tiffcomp)
{
l_int32  comptype;
 
    switch (tiffcomp)
    {
    case COMPRESSION_CCITTFAX4:
        comptype = IFF_TIFF_G4;
        break;
    case COMPRESSION_CCITTFAX3:
        comptype = IFF_TIFF_G3;
        break;
    case COMPRESSION_CCITTRLE:
        comptype = IFF_TIFF_RLE;
        break;
    case COMPRESSION_PACKBITS:
        comptype = IFF_TIFF_PACKBITS;
        break;
    case COMPRESSION_LZW:
        comptype = IFF_TIFF_LZW;
        break;
    case COMPRESSION_ADOBE_DEFLATE:
        comptype = IFF_TIFF_ZIP;
        break;
    case COMPRESSION_JPEG:
        comptype = IFF_TIFF_JPEG;
        break;
    default:
        comptype = IFF_TIFF;
        break;
    }
    return comptype;
}
 
 
/*--------------------------------------------------------------*
 *                   Extraction of tiff g4 data                 *
 *--------------------------------------------------------------*/
l_ok
extractG4DataFromFile(const char  *filein,
                      l_uint8    **pdata,
                      size_t      *pnbytes,
                      l_int32     *pw,
                      l_int32     *ph,
                      l_int32     *pminisblack)
{
l_uint8  *inarray, *data;
l_uint16  minisblack, comptype;  /* accessors require l_uint16 */
l_int32   istiff;
l_uint32  w, h, rowsperstrip;  /* accessors require l_uint32 */
l_uint32  diroff;
size_t    fbytes, nbytes;
FILE     *fpin;
TIFF     *tif;
 
    PROCNAME("extractG4DataFromFile");
 
    if (!pdata)
        return ERROR_INT("&data not defined", procName, 1);
    if (!pnbytes)
        return ERROR_INT("&nbytes not defined", procName, 1);
    if (!pw && !ph && !pminisblack)
        return ERROR_INT("no output data requested", procName, 1);
    *pdata = NULL;
    *pnbytes = 0;
 
    if ((fpin = fopenReadStream(filein)) == NULL)
        return ERROR_INT("stream not opened to file", procName, 1);
    istiff = fileFormatIsTiff(fpin);
    fclose(fpin);
    if (!istiff)
        return ERROR_INT("filein not tiff", procName, 1);
 
    if ((inarray = l_binaryRead(filein, &fbytes)) == NULL)
        return ERROR_INT("inarray not made", procName, 1);
 
        /* Get metadata about the image */
    if ((tif = openTiff(filein, "rb")) == NULL) {
        LEPT_FREE(inarray);
        return ERROR_INT("tif not open for read", procName, 1);
    }
    TIFFGetField(tif, TIFFTAG_COMPRESSION, &comptype);
    if (comptype != COMPRESSION_CCITTFAX4) {
        LEPT_FREE(inarray);
        TIFFClose(tif);
        return ERROR_INT("filein is not g4 compressed", procName, 1);
    }
 
    TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &w);
    TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &h);
    TIFFGetField(tif, TIFFTAG_ROWSPERSTRIP, &rowsperstrip);
    if (h != rowsperstrip)
        L_WARNING("more than 1 strip\n", procName);
    TIFFGetField(tif, TIFFTAG_PHOTOMETRIC, &minisblack);  /* for 1 bpp */
/*    TIFFPrintDirectory(tif, stderr, 0); */
    TIFFClose(tif);
    if (pw) *pw = (l_int32)w;
    if (ph) *ph = (l_int32)h;
    if (pminisblack) *pminisblack = (l_int32)minisblack;
 
        /* The header has 8 bytes: the first 2 are the magic number,
         * the next 2 are the version, and the last 4 are the
         * offset to the first directory.  That's what we want here.
         * We have to test the byte order before decoding 4 bytes! */
    if (inarray[0] == 0x4d) {  /* big-endian */
        diroff = (inarray[4] << 24) | (inarray[5] << 16) |
                 (inarray[6] << 8) | inarray[7];
    } else  {   /* inarray[0] == 0x49 :  little-endian */
        diroff = (inarray[7] << 24) | (inarray[6] << 16) |
                 (inarray[5] << 8) | inarray[4];
    }
/*    lept_stderr(" diroff = %d, %x\n", diroff, diroff); */
 
        /* Extract the ccittg4 encoded data from the tiff file.
         * We skip the 8 byte header and take nbytes of data,
         * up to the beginning of the directory (at diroff)  */
    nbytes = diroff - 8;
    if (nbytes > MaxNumTiffBytes) {
        LEPT_FREE(inarray);
        L_ERROR("requesting %zu bytes > %zu\n", procName,
                nbytes, MaxNumTiffBytes);
        return 1;
    }
    *pnbytes = nbytes;
    if ((data = (l_uint8 *)LEPT_CALLOC(nbytes, sizeof(l_uint8))) == NULL) {
        LEPT_FREE(inarray);
        return ERROR_INT("data not allocated", procName, 1);
    }
    *pdata = data;
    memcpy(data, inarray + 8, nbytes);
    LEPT_FREE(inarray);
 
    return 0;
}
 
 
/*--------------------------------------------------------------*
 *               Open tiff stream from file stream              *
 *--------------------------------------------------------------*/
static TIFF *
fopenTiff(FILE        *fp,
          const char  *modestring)
{
    PROCNAME("fopenTiff");
 
    if (!fp)
        return (TIFF *)ERROR_PTR("stream not opened", procName, NULL);
    if (!modestring)
        return (TIFF *)ERROR_PTR("modestring not defined", procName, NULL);
 
    TIFFSetWarningHandler(NULL);  /* disable warnings */
    TIFFSetErrorHandler(NULL);  /* disable error messages */
 
    fseek(fp, 0, SEEK_SET);
    return TIFFClientOpen("TIFFstream", modestring, (thandle_t)fp,
                          lept_read_proc, lept_write_proc, lept_seek_proc,
                          lept_close_proc, lept_size_proc, NULL, NULL);
}
 
 
/*--------------------------------------------------------------*
 *                      Wrapper for TIFFOpen                    *
 *--------------------------------------------------------------*/
static TIFF *
openTiff(const char  *filename,
         const char  *modestring)
{
char  *fname;
TIFF  *tif;
 
    PROCNAME("openTiff");
 
    if (!filename)
        return (TIFF *)ERROR_PTR("filename not defined", procName, NULL);
    if (!modestring)
        return (TIFF *)ERROR_PTR("modestring not defined", procName, NULL);
 
    TIFFSetWarningHandler(NULL);  /* disable warnings */
    TIFFSetErrorHandler(NULL);  /* disable error messages */
 
    fname = genPathname(filename, NULL);
    tif = TIFFOpen(fname, modestring);
    LEPT_FREE(fname);
    return tif;
}
 
 
/*----------------------------------------------------------------------*
 *     Memory I/O: reading memory --> pix and writing pix --> memory    *
 *----------------------------------------------------------------------*/
/*  It would be nice to use open_memstream() and fmemopen()
 *  for writing and reading to memory, rsp.  These functions manage
 *  memory for writes and reads that use a file streams interface.
 *  Unfortunately, the tiff library only has an interface for reading
 *  and writing to file descriptors, not to file streams.  The tiff
 *  library procedure is to open a "tiff stream" and read/write to it.
 *  The library provides a client interface for managing the I/O
 *  from memory, which requires seven callbacks.  See the TIFFClientOpen
 *  man page for callback signatures.  Adam Langley provided the code
 *  to do this.  */
 
struct L_Memstream
{
    l_uint8   *buffer;    /* expands to hold data when written to;         */
                          /* fixed size when read from.                    */
    size_t     bufsize;   /* current size allocated when written to;       */
                          /* fixed size of input data when read from.      */
    size_t     offset;    /* byte offset from beginning of buffer.         */
    size_t     hw;        /* high-water mark; max bytes in buffer.         */
    l_uint8  **poutdata;  /* input param for writing; data goes here.      */
    size_t    *poutsize;  /* input param for writing; data size goes here. */
};
typedef struct L_Memstream  L_MEMSTREAM;
 
 
    /* These are static functions for memory I/O */
static L_MEMSTREAM *memstreamCreateForRead(l_uint8 *indata, size_t pinsize);
static L_MEMSTREAM *memstreamCreateForWrite(l_uint8 **poutdata,
                                            size_t *poutsize);
static tsize_t tiffReadCallback(thandle_t handle, tdata_t data, tsize_t length);
static tsize_t tiffWriteCallback(thandle_t handle, tdata_t data,
                                 tsize_t length);
static toff_t tiffSeekCallback(thandle_t handle, toff_t offset, l_int32 whence);
static l_int32 tiffCloseCallback(thandle_t handle);
static toff_t tiffSizeCallback(thandle_t handle);
static l_int32 tiffMapCallback(thandle_t handle, tdata_t *data, toff_t *length);
static void tiffUnmapCallback(thandle_t handle, tdata_t data, toff_t length);
 
 
static L_MEMSTREAM *
memstreamCreateForRead(l_uint8  *indata,
                       size_t    insize)
{
L_MEMSTREAM  *mstream;
 
    mstream = (L_MEMSTREAM *)LEPT_CALLOC(1, sizeof(L_MEMSTREAM));
    mstream->buffer = indata;   /* handle to input data array */
    mstream->bufsize = insize;  /* amount of input data */
    mstream->hw = insize;       /* high-water mark fixed at input data size */
    mstream->offset = 0;        /* offset always starts at 0 */
    return mstream;
}
 
 
static L_MEMSTREAM *
memstreamCreateForWrite(l_uint8  **poutdata,
                        size_t    *poutsize)
{
L_MEMSTREAM  *mstream;
 
    mstream = (L_MEMSTREAM *)LEPT_CALLOC(1, sizeof(L_MEMSTREAM));
    mstream->buffer = (l_uint8 *)LEPT_CALLOC(8 * 1024, 1);
    mstream->bufsize = 8 * 1024;
    mstream->poutdata = poutdata;  /* used only at end of write */
    mstream->poutsize = poutsize;  /* ditto  */
    mstream->hw = mstream->offset = 0;
    return mstream;
}
 
 
static tsize_t
tiffReadCallback(thandle_t  handle,
                 tdata_t    data,
                 tsize_t    length)
{
L_MEMSTREAM  *mstream;
size_t        amount;
 
    mstream = (L_MEMSTREAM *)handle;
    amount = L_MIN((size_t)length, mstream->hw - mstream->offset);
 
        /* Fuzzed files can create this condition! */
    if (mstream->offset + amount < amount ||  /* overflow */
        mstream->offset + amount > mstream->hw) {
        lept_stderr("Bad file: amount too big: %zu\n", amount);
        return 0;
    }
 
    memcpy(data, mstream->buffer + mstream->offset, amount);
    mstream->offset += amount;
    return amount;
}
 
 
static tsize_t
tiffWriteCallback(thandle_t  handle,
                  tdata_t    data,
                  tsize_t    length)
{
L_MEMSTREAM  *mstream;
size_t        newsize;
 
        /* reallocNew() uses calloc to initialize the array.
         * If malloc is used instead, for some of the encoding methods,
         * not all the data in 'bufsize' bytes in the buffer will
         * have been initialized by the end of the compression. */
    mstream = (L_MEMSTREAM *)handle;
    if (mstream->offset + length > mstream->bufsize) {
        newsize = 2 * (mstream->offset + length);
        mstream->buffer = (l_uint8 *)reallocNew((void **)&mstream->buffer,
                                                mstream->hw, newsize);
        mstream->bufsize = newsize;
    }
 
    memcpy(mstream->buffer + mstream->offset, data, length);
    mstream->offset += length;
    mstream->hw = L_MAX(mstream->offset, mstream->hw);
    return length;
}
 
 
static toff_t
tiffSeekCallback(thandle_t  handle,
                 toff_t     offset,
                 l_int32    whence)
{
L_MEMSTREAM  *mstream;
 
    PROCNAME("tiffSeekCallback");
    mstream = (L_MEMSTREAM *)handle;
    switch (whence) {
        case SEEK_SET:
/*            lept_stderr("seek_set: offset = %d\n", offset); */
            if((size_t)offset != offset) {  /* size_t overflow on uint32 */
                return (toff_t)ERROR_INT("too large offset value", procName, 1);
            }
            mstream->offset = offset;
            break;
        case SEEK_CUR:
/*            lept_stderr("seek_cur: offset = %d\n", offset); */
            mstream->offset += offset;
            break;
        case SEEK_END:
/*            lept_stderr("seek end: hw = %d, offset = %d\n",
                    mstream->hw, offset); */
            mstream->offset = mstream->hw - offset;  /* offset >= 0 */
            break;
        default:
            return (toff_t)ERROR_INT("bad whence value", procName,
                                     mstream->offset);
    }
 
    return mstream->offset;
}
 
 
static l_int32
tiffCloseCallback(thandle_t  handle)
{
L_MEMSTREAM  *mstream;
 
    mstream = (L_MEMSTREAM *)handle;
    if (mstream->poutdata) {   /* writing: save the output data */
        *mstream->poutdata = mstream->buffer;
        *mstream->poutsize = mstream->hw;
    }
    LEPT_FREE(mstream);  /* never free the buffer! */
    return 0;
}
 
 
static toff_t
tiffSizeCallback(thandle_t  handle)
{
L_MEMSTREAM  *mstream;
 
    mstream = (L_MEMSTREAM *)handle;
    return mstream->hw;
}
 
 
static l_int32
tiffMapCallback(thandle_t  handle,
                tdata_t   *data,
                toff_t    *length)
{
L_MEMSTREAM  *mstream;
 
    mstream = (L_MEMSTREAM *)handle;
    *data = mstream->buffer;
    *length = mstream->hw;
    return 0;
}
 
 
static void
tiffUnmapCallback(thandle_t  handle,
                  tdata_t    data,
                  toff_t     length)
{
    return;
}
 
 
static TIFF *
fopenTiffMemstream(const char  *filename,
                   const char  *operation,
                   l_uint8    **pdata,
                   size_t      *pdatasize)
{
L_MEMSTREAM  *mstream;
TIFF         *tif;
 
    PROCNAME("fopenTiffMemstream");
 
    if (!filename)
        return (TIFF *)ERROR_PTR("filename not defined", procName, NULL);
    if (!operation)
        return (TIFF *)ERROR_PTR("operation not defined", procName, NULL);
    if (!pdata)
        return (TIFF *)ERROR_PTR("&data not defined", procName, NULL);
    if (!pdatasize)
        return (TIFF *)ERROR_PTR("&datasize not defined", procName, NULL);
    if (strcmp(operation, "r") && strcmp(operation, "w"))
        return (TIFF *)ERROR_PTR("op not 'r' or 'w'", procName, NULL);
 
    if (!strcmp(operation, "r"))
        mstream = memstreamCreateForRead(*pdata, *pdatasize);
    else
        mstream = memstreamCreateForWrite(pdata, pdatasize);
 
    TIFFSetWarningHandler(NULL);  /* disable warnings */
    TIFFSetErrorHandler(NULL);  /* disable error messages */
 
    tif = TIFFClientOpen(filename, operation, (thandle_t)mstream,
                         tiffReadCallback, tiffWriteCallback,
                         tiffSeekCallback, tiffCloseCallback,
                         tiffSizeCallback, tiffMapCallback,
                         tiffUnmapCallback);
    if (!tif)
        LEPT_FREE(mstream);
    return tif;
}
 
 
PIX *
pixReadMemTiff(const l_uint8  *cdata,
               size_t          size,
               l_int32         n)
{
l_uint8  *data;
l_int32   i;
PIX      *pix;
TIFF     *tif;
 
    PROCNAME("pixReadMemTiff");
 
    if (!cdata)
        return (PIX *)ERROR_PTR("cdata not defined", procName, NULL);
 
    data = (l_uint8 *)cdata;  /* we're really not going to change this */
    if ((tif = fopenTiffMemstream("tifferror", "r", &data, &size)) == NULL)
        return (PIX *)ERROR_PTR("tiff stream not opened", procName, NULL);
 
    pix = NULL;
    for (i = 0; ; i++) {
        if (i == n) {
            if ((pix = pixReadFromTiffStream(tif)) == NULL) {
                TIFFClose(tif);
                return NULL;
            }
            pixSetInputFormat(pix, IFF_TIFF);
            break;
        }
        if (TIFFReadDirectory(tif) == 0)
            break;
        if (i == ManyPagesInTiffFile + 1) {
            L_WARNING("big file: more than %d pages\n", procName,
                      ManyPagesInTiffFile);
        }
    }
 
    TIFFClose(tif);
    return pix;
}
 
 
PIX *
pixReadMemFromMultipageTiff(const l_uint8  *cdata,
                            size_t          size,
                            size_t         *poffset)
{
l_uint8  *data;
l_int32   retval;
size_t    offset;
PIX      *pix;
TIFF     *tif;
 
    PROCNAME("pixReadMemFromMultipageTiff");
 
    if (!cdata)
        return (PIX *)ERROR_PTR("cdata not defined", procName, NULL);
    if (!poffset)
        return (PIX *)ERROR_PTR("&offset not defined", procName, NULL);
 
    data = (l_uint8 *)cdata;  /* we're really not going to change this */
    if ((tif = fopenTiffMemstream("tifferror", "r", &data, &size)) == NULL)
        return (PIX *)ERROR_PTR("tiff stream not opened", procName, NULL);
 
        /* Set ptrs in the TIFF to the beginning of the image */
    offset = *poffset;
    retval = (offset == 0) ? TIFFSetDirectory(tif, 0)
                           : TIFFSetSubDirectory(tif, offset);
    if (retval == 0) {
        TIFFClose(tif);
        return NULL;
    }
 
    if ((pix = pixReadFromTiffStream(tif)) == NULL) {
        TIFFClose(tif);
        return NULL;
    }
 
        /* Advance to the next image and return the new offset */
    TIFFReadDirectory(tif);
    *poffset = TIFFCurrentDirOffset(tif);
    TIFFClose(tif);
    return pix;
}
 
 
PIXA *
pixaReadMemMultipageTiff(const l_uint8  *data,
                         size_t          size)
{
size_t  offset;
PIX    *pix;
PIXA   *pixa;
 
    PROCNAME("pixaReadMemMultipageTiff");
 
    if (!data)
        return (PIXA *)ERROR_PTR("data not defined", procName, NULL);
 
    offset = 0;
    pixa = pixaCreate(0);
    do {
        pix = pixReadMemFromMultipageTiff(data, size, &offset);
        pixaAddPix(pixa, pix, L_INSERT);
    } while (offset != 0);
    return pixa;
}
 
 
l_ok
pixaWriteMemMultipageTiff(l_uint8  **pdata,
                          size_t    *psize,
                          PIXA      *pixa)
{
const char  *modestr;
l_int32      i, n;
FILE        *fp;
PIX         *pix1;
 
    PROCNAME("pixaWriteMemMultipageTiff");
 
    if (pdata) *pdata = NULL;
    if (!pdata)
        return ERROR_INT("pdata not defined", procName, 1);
    if (!pixa)
        return ERROR_INT("pixa not defined", procName, 1);
 
#ifdef _WIN32
    if ((fp = fopenWriteWinTempfile()) == NULL)
        return ERROR_INT("tmpfile stream not opened", procName, 1);
#else
    if ((fp = tmpfile()) == NULL)
        return ERROR_INT("tmpfile stream not opened", procName, 1);
#endif  /* _WIN32 */
 
    n = pixaGetCount(pixa);
    for (i = 0; i < n; i++) {
        modestr = (i == 0) ? "w" : "a";
        pix1 = pixaGetPix(pixa, i, L_CLONE);
        if (pixGetDepth(pix1) == 1)
            pixWriteStreamTiffWA(fp, pix1, IFF_TIFF_G4, modestr);
        else
            pixWriteStreamTiffWA(fp, pix1, IFF_TIFF_ZIP, modestr);
        pixDestroy(&pix1);
    }
 
    rewind(fp);
    *pdata = l_binaryReadStream(fp, psize);
    fclose(fp);
    return 0;
}
 
 
l_ok
pixWriteMemTiff(l_uint8  **pdata,
                size_t    *psize,
                PIX       *pix,
                l_int32    comptype)
{
    return pixWriteMemTiffCustom(pdata, psize, pix, comptype,
                                 NULL, NULL, NULL, NULL);
}
 
 
l_ok
pixWriteMemTiffCustom(l_uint8  **pdata,
                      size_t    *psize,
                      PIX       *pix,
                      l_int32    comptype,
                      NUMA      *natags,
                      SARRAY    *savals,
                      SARRAY    *satypes,
                      NUMA      *nasizes)
{
l_int32  ret;
TIFF    *tif;
 
    PROCNAME("pixWriteMemTiffCustom");
 
    if (!pdata)
        return ERROR_INT("&data not defined", procName, 1);
    if (!psize)
        return ERROR_INT("&size not defined", procName, 1);
    if (!pix)
        return ERROR_INT("&pix not defined", procName, 1);
    if (pixGetDepth(pix) != 1 && comptype != IFF_TIFF &&
        comptype != IFF_TIFF_LZW && comptype != IFF_TIFF_ZIP &&
        comptype != IFF_TIFF_JPEG) {
        L_WARNING("invalid compression type for bpp > 1\n", procName);
        comptype = IFF_TIFF_ZIP;
    }
 
    if ((tif = fopenTiffMemstream("tifferror", "w", pdata, psize)) == NULL)
        return ERROR_INT("tiff stream not opened", procName, 1);
    ret = pixWriteToTiffStream(tif, pix, comptype, natags, savals,
                               satypes, nasizes);
 
    TIFFClose(tif);
    return ret;
}
 
/* --------------------------------------------*/
#endif  /* HAVE_LIBTIFF */
/* --------------------------------------------*/