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/* Copyright (C) 1994, 2000 Aladdin Enterprises.  All rights reserved.
  
  This software is provided AS-IS with no warranty, either express or
  implied.
  
  This software is distributed under license and may not be copied,
  modified or distributed except as expressly authorized under the terms
  of the license contained in the file LICENSE in this distribution.
  
  For more information about licensing, please refer to
  http://www.ghostscript.com/licensing/. For information on
  commercial licensing, go to http://www.artifex.com/licensing/ or
  contact Artifex Software, Inc., 101 Lucas Valley Road #110,
  San Rafael, CA  94903, U.S.A., +1(415)492-9861.
*/

/* $Id: gdevtifs.h,v 1.6 2002/06/16 07:25:26 lpd Exp $ */
/* Definitions for writing TIFF file formats. */

#ifndef gdevtifs_INCLUDED
#  define gdevtifs_INCLUDED

/* ================ TIFF specification ================ */

/* Based on TIFF specification version 6.0 obtained from */
/* sgi.com:graphics/tiff/TIFF6.ps.Z. */

/*
 * The sizes of TIFF data types are system-independent.  Therefore,
 * we cannot use short, long, etc., but must use types of known sizes.
 */
#if arch_sizeof_short == 2
typedef short TIFF_short;	/* no plausible alternative */
typedef unsigned short TIFF_ushort;

#endif
#if arch_sizeof_int == 4
typedef int TIFF_long;
typedef unsigned int TIFF_ulong;

#else
# if arch_sizeof_long == 4
typedef long TIFF_long;
typedef unsigned long TIFF_ulong;

# endif
#endif

/*
 * Define the TIFF file header.
 */
typedef struct TIFF_header_s {
    TIFF_ushort magic;		/* magic number (defines byte order) */
    TIFF_ushort version;	/* TIFF version number */
    TIFF_ulong diroff;		/* byte offset to first directory */
} TIFF_header;

#define	TIFF_magic_big_endian		0x4d4d	/* 'MM' */
#define	TIFF_magic_little_endian	0x4949	/* 'II' */

#define	TIFF_version_value	42

/*
 * Define an individual entry in a TIFF directory.  Within a directory,
 * the entries must be sorted by increasing tag value.
 *
 * The value field contains either the offset of the field data in the file,
 * or, if the value fits in 32 bits, the value itself, left-justified.
 * Field data may appear anywhere in the file, so long as each data block is
 * aligned on a 32-bit boundary and is disjoint from all other data blocks.
 */
typedef struct TIFF_dir_entry_s {
    TIFF_ushort tag;		/* TIFF_tag */
    TIFF_ushort type;		/* TIFF_data_type */
    TIFF_ulong count;		/* number of items (spec calls this 'length') */
    TIFF_ulong value;		/* byte offset to field data, */
    /* or actual value if <=4 bytes */
} TIFF_dir_entry;

/*
 * Define the tag data type values.
 */
typedef enum {
    TIFF_BYTE = 1,		/* 8-bit unsigned integer */
    TIFF_ASCII = 2,		/* 8-bit bytes with last byte null */
    TIFF_SHORT = 3,		/* 16-bit unsigned integer */
    TIFF_LONG = 4,		/* 32-bit unsigned integer */
    TIFF_RATIONAL = 5,		/* 64-bit unsigned fraction */
    /* (ratio of two 32-bit unsigned integers) */
    TIFF_SBYTE = 6,		/* 8-bit signed integer */
    TIFF_UNDEFINED = 7,		/* 8-bit untyped data */
    TIFF_SSHORT = 8,		/* 16-bit signed integer */
    TIFF_SLONG = 9,		/* 32-bit signed integer */
    TIFF_SRATIONAL = 10,	/* 64-bit signed fraction */
    /* (ratio of two 32-bit signed integers) */
    TIFF_FLOAT = 11,		/* 32-bit IEEE floating point */
    TIFF_DOUBLE = 12,		/* 64-bit IEEE floating point */
    /* A flag to indicate the value is indirect. */
    /* This is only used internally; it is not part of the */
    /* TIFF specification (although it should be!). */
    TIFF_INDIRECT = 128
} TIFF_data_type;

/*
 * Define the tag values we need.  Note that this is only a very small subset
 * of all the values defined in the TIFF specification; we will add more
 * as the need arises.
 */
typedef enum {
    TIFFTAG_SubFileType = 254,	/* subfile data descriptor */
#define	    SubFileType_reduced_image	0x1	/* reduced resolution version */
#define	    SubFileType_page		0x2	/* one page of many */
#define	    SubFileType_mask		0x4	/* transparency mask */
    TIFFTAG_ImageWidth = 256,	/* image width in pixels */
    TIFFTAG_ImageLength = 257,	/* image height in pixels */
    TIFFTAG_BitsPerSample = 258,	/* bits per channel (sample) */
    TIFFTAG_Compression = 259,	/* data compression technique */
#define	    Compression_none		1	/* dump mode */
#define	    Compression_CCITT_RLE	2	/* CCITT modified Huffman RLE */
#define	    Compression_CCITT_T4	3	/* CCITT T.4 fax encoding */
#define	    Compression_CCITT_T6	4	/* CCITT T.6 fax encoding */
#define	    Compression_LZW		5	/* Lempel-Ziv  & Welch */
#define	    Compression_JPEG		6	/* !JPEG compression */
#define	    Compression_NeXT		32766	/* NeXT 2-bit RLE */
#define	    Compression_CCITT_RLEW	32771	/* #1 w/ word alignment */
#define	    Compression_PackBits	32773	/* Macintosh RLE */
#define	    Compression_Thunderscan	32809	/* ThunderScan RLE */
    TIFFTAG_Photometric = 262,	/* photometric interpretation */
#define	    Photometric_min_is_white	0	/* min value is white */
#define	    Photometric_min_is_black	1	/* min value is black */
#define	    Photometric_RGB		2	/* RGB color model */
#define	    Photometric_palette		3	/* color map indexed */
#define	    Photometric_mask		4	/* $holdout mask */
#define	    Photometric_separated	5	/* !color separations */
#define	    Photometric_YCbCr		6	/* !CCIR 601 */
#define	    Photometric_CIE_Lab		8	/* !1976 CIE L*a*b* */
    TIFFTAG_FillOrder = 266,	/* data order within a byte */
#define	    FillOrder_MSB2LSB		1	/* most significant -> least */
#define	    FillOrder_LSB2MSB		2	/* least significant -> most */
    TIFFTAG_StripOffsets = 273,	/* offsets to data strips */
    TIFFTAG_Orientation = 274,	/* +image Orientation */
#define	    Orientation_top_left	1	/* row 0 top, col 0 lhs */
#define	    Orientation_top_right	2	/* row 0 top, col 0 rhs */
#define	    Orientation_bot_right	3	/* row 0 bottom, col 0 rhs */
#define	    Orientation_bot_left	4	/* row 0 bottom, col 0 lhs */
#define	    Orientation_left_top	5	/* row 0 lhs, col 0 top */
#define	    Orientation_right_top	6	/* row 0 rhs, col 0 top */
#define	    Orientation_right_bot	7	/* row 0 rhs, col 0 bottom */
#define	    Orientation_left_bot	8	/* row 0 lhs, col 0 bottom */
    TIFFTAG_SamplesPerPixel = 277,	/* samples per pixel */
    TIFFTAG_RowsPerStrip = 278,	/* rows per strip of data */
    TIFFTAG_StripByteCounts = 279,	/* bytes counts for strips */
    TIFFTAG_XResolution = 282,	/* pixels/resolution in x */
    TIFFTAG_YResolution = 283,	/* pixels/resolution in y */
    TIFFTAG_PlanarConfig = 284,	/* storage organization */
#define	    PlanarConfig_contig		1	/* single image plane */
#define	    PlanarConfig_separate	2	/* separate planes of data */
    TIFFTAG_T4Options = 292,	/* 32 flag bits */
#define	    T4Options_2D_encoding	0x1	/* 2-dimensional coding */
#define	    T4Options_uncompressed	0x2	/* data not compressed */
#define	    T4Options_fill_bits		0x4	/* fill to byte boundary */
    TIFFTAG_T6Options = 293,	/* 32 flag bits */
#define	    T6Options_uncompressed	0x2	/* data not compressed */
    TIFFTAG_ResolutionUnit = 296,	/* units of resolutions */
#define	    ResolutionUnit_none		1	/* no meaningful units */
#define	    ResolutionUnit_inch		2	/* english */
#define	    ResolutionUnit_centimeter	3	/* metric */
    TIFFTAG_PageNumber = 297,	/* page number if multi-page */
    TIFFTAG_Software = 305,	/* software name & release */
    TIFFTAG_DateTime = 306,	/* creation date and time */
    /*
     * The CleanFaxData tag isn't in the TIFF 6 documentation, and many
     * TIFF-reading applications don't recognize it.  Don't use it!
     */
    TIFFTAG_CleanFaxData = 327	/* regenerated line info */
#define	    CleanFaxData_clean		0	/* no errors detected */
#define	    CleanFaxData_regenerated	1	/* receiver regenerated lines */
#define	    CleanFaxData_unclean	2	/* uncorrected errors exist */
} TIFF_tag;

/* ================ Implementation ================ */

/*
 * Define the added driver state for TIFF writing.  Note that we provide
 * no GC descriptor, so this structure must exist only on the stack,
 * never in allocated storage.
 */
typedef struct gdev_tiff_state_s {
    gs_memory_t *mem;
    long prev_dir;		/* file offset of previous directory offset */
    long dir_off;		/* file offset of next write */
    int ntags;			/* # of tags in directory */
    long strip_index;		/* current strip being output, 0 = first */
    long strip_count;		
    long rows;		
    /* Record offsets of values - these may be indirect if more than one strip */
    int offset_StripOffsets; 
    int offset_StripByteCounts;
    TIFF_ulong *StripOffsets;
    TIFF_ulong *StripByteCounts;
} gdev_tiff_state;

/*
 * Begin writing a TIFF page.  This procedure supplies a standard set of
 * tags; the client can provide additional tags (pre-sorted) and
 * indirect values.
 */
int gdev_tiff_begin_page(gx_device_printer * pdev, gdev_tiff_state * tifs,
			 FILE * fp,
			 const TIFF_dir_entry * entries, int entry_count,
			 const byte * values, int value_size,
			 long max_strip_size);

/*
 * Finish writing a TIFF strip.  All data written since begin or last
 * end_strip is considered to be a single strip.
 */
int gdev_tiff_end_strip(gdev_tiff_state * tifs, FILE * fp);

/*
 * Finish writing a TIFF page.  StripOffsets and StripByteCounts are
 * patched into the file.
 */
int gdev_tiff_end_page(gdev_tiff_state * tifs, FILE * fp);

#endif /* gdevtifs_INCLUDED */

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