IRIX Base Documentation 1998 November/IRIX 6.5.2 Base Documentation November 1998.img/usr/share/catman/p_man/cat3/ifl/libtiff.z/libtiff

Text File | 1998-10-20 | 23KB | 392 lines

IIIINNNNTTTTRRRROOOO((((3333TTTT))))         IIIImmmmaaaaggggeeee FFFFoooorrrrmmmmaaaatttt LLLLiiiibbbbrrrraaaarrrryyyy CCCC++++++++ RRRReeeeffffeeeerrrreeeennnncccceeee MMMMaaaannnnuuuuaaaallll          IIIINNNNTTTTRRRROOOO((((3333TTTT))))



NNNNAAAAMMMMEEEE
     libtiff - introduction to _l_i_b_t_i_f_f, a library for reading and writing TIFF
     files

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
     ####iiiinnnncccclllluuuuddddeeee <<<<ttttiiiiffffffffiiiioooo....hhhh>>>>
     cc file.c ----llllttttiiiiffffffff

DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     _l_i_b_t_i_f_f is a library for reading and writing data files encoded with the
     _T_a_g _I_m_a_g_e _F_i_l_e format, Revision 6.0 (or revision 5.0 or revision 4.0).
     This file format is suitable for archiving multi-color and monochromatic
     image data.

     The library supports several compression algorithms, as indicated by the
     _C_o_m_p_r_e_s_s_i_o_n field, including:  no compression (1), CCITT 1D Huffman
     compression (2), CCITT Group 3 Facsimile compression (3), CCITT Group 4
     Facsimile compression (4), Lempel-Ziv & Welch compression (5), baseline
     JPEG compression (7), word-aligned 1D Huffman compression (32771), and
     PackBits compression (32773).  In addition, several nonstandard
     compression algorithms are supported:  the 4-bit compression algorithm
     used by the _T_h_u_n_d_e_r_S_c_a_n program (32809) (decompression only), NeXT's 2-
     bit compression algorithm (32766) (decompression only), and an
     experimental LZ-style algorithm known as Deflate (32946).  Directory
     information may be in either little- or big-endian byte order-byte
     swapping is automatically done by the library.  Data bit ordering may be
     either Most Significant Bit (MSB) to Least Significant Bit (LSB) or LSB
     to MSB.  Finally, the library does not support files in which the
     _B_i_t_s_P_e_r_S_a_m_p_l_e, _C_o_m_p_r_e_s_s_i_o_n, _M_i_n_S_a_m_p_l_e_V_a_l_u_e, or _M_a_x_S_a_m_p_l_e_V_a_l_u_e fields are
     defined differently on a per-sample basis (in Rev. 6.0 the _C_o_m_p_r_e_s_s_i_o_n
     tag is not defined on a per-sample basis, so this is immaterial).

DDDDAAAATTTTAAAA TTTTYYYYPPPPEEEESSSS
     The library makes extensive use of C typedefs to promote portability.
     Two sets of typedefs are used, one for communication with clients of the
     library and one for internal data structures and parsing of the TIFF
     format.  The following typedefs are exposed to users either through
     function definitions or through parameters passed through the varargs
     interfaces.
          typedef unsigned short uint16;      16-bit unsigned integer
          typedef unsigned <_t_h_i_n_g> uint32;    32-bit unsigned integer
          typedef unsigned int ttag_t;        directory tag
          typedef uint16 tdir_t;              directory index
          typedef uint16 tsample_t;           sample number
          typedef uint32 tstrip_t;            strip number
          typedef uint32 ttile_t;             tile number
          typedef int32 tsize_t;              i/o size in bytes
          typedef void* tdata_t;              image data ref
          typedef void* thandle_t;            client data handle
          typedef int32 toff_t;               file offset
     Note that _t_s_t_r_i_p__t, _t_t_i_l_e__t, and _t_s_i_z_e__t are constrained to be no more


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IIIINNNNTTTTRRRROOOO((((3333TTTT))))         IIIImmmmaaaaggggeeee FFFFoooorrrrmmmmaaaatttt LLLLiiiibbbbrrrraaaarrrryyyy CCCC++++++++ RRRReeeeffffeeeerrrreeeennnncccceeee MMMMaaaannnnuuuuaaaallll          IIIINNNNTTTTRRRROOOO((((3333TTTT))))



     than 32-bit quantities by 32-bit fields they are stored in in the TIFF
     image.  Likewise _t_s_a_m_p_l_e__t is limited by the 16-bit field used to store
     the _S_a_m_p_l_e_s_P_e_r_P_i_x_e_l tag.  _t_d_i_r__t constrains the maximum number of IFDs
     that may appear in an image and may be an arbitrary size (w/o penalty).
     _t_t_a_g__t must be either int, unsigned int, pointer, or double because the
     library uses a varargs interface and ANSI C restricts the type of the
     parameter before an ellipsis to be a promoted type.  _t_o_f_f__t is defined as
     int32 because TIFF file offsets are (unsigned) 32-bit quantities.  A
     signed value is used because some interfaces return -1 on error.
     Finally, note that user-specified data references are passed as opaque
     handles and only cast at the lowest layers where their type is presumed.

LLLLIIIISSSSTTTT OOOOFFFF RRRROOOOUUUUTTTTIIIINNNNEEEESSSS
     The following routines are part of the library.  Consult specific manual
     pages for details on their operation.  The manual page names listed below
     are for systems where the full function names can not be encoded in the
     filesystem; on most systems doing ``man function-name'' will work.
     _N_a_m_e                   _A_p_p_e_a_r_s _o_n _P_a_g_e  _D_e_s_c_r_i_p_t_i_o_n
     TIFFCheckTile          tile.3t          very x,y,z,sample is within image
     TIFFClientOpen         open.3t          open a file for reading or writing
     TIFFClose              close.3t         close an open file
     TIFFComputeStrip       strip.3t         return strip containing y,sample
     TIFFComputeTile        tile.3t          return tile containing x,y,z,sample
     TIFFCurrentDirectory   query.3t         return index of current directory
     TIFFCurrentRow         query.3t         return index of current scanline
     TIFFCurrentStrip       query.3t         return index of current strip
     TIFFCurrentTile        query.3t         return index of current tile
     TIFFError              error.3t         library error handler
     TIFFFdOpen             open.3t          open a file for reading or writing
     TIFFFileName           query.3t         return name of open file
     TIFFFileno             query.3t         return open file descriptor
     TIFFFlush              flush.3t         flush all pending writes
     TIFFFlushData          flush.3t         flush pending data writes
     TIFFGetBitRevTable     swab.3t          return bit reversal table
     TIFFGetField           getfield.3t      return tag value in current directory
     TIFFGetFieldDefaulted  getfield.3t      return tag value in current directory
     TIFFGetMode            query.3t         return open file mode
     TIFFGetVersion         query.3t         return library version string
     TIFFIsTiled            query.3t         return true if image data is tiled
     TIFFIsByteSwapped      query.3t         return true if image data is byte-swapped
     TIFFNumberOfStrips     strip.3t         return number of strips in an image
     TIFFNumberOfTiles      tile.3t          return number of tiles in an image
     TIFFOpen               open.3t          open a file for reading or writing
     TIFFPrintDirectory     print.3t         print description of the current directory
     TIFFReadBufferSetup    rdbuf.3t         specify i/o buffer for reading
     TIFFReadDirectory      readdir.3t       read the next directory
     TIFFReadEncodedStrip   rdestrip.3t      read and decode a strip of data
     TIFFReadEncodedTile    rdetile.3t       read and decode a tile of data
     TIFFReadRawStrip       rdrstrip.3t      read a raw strip of data
     TIFFReadRawTile        rdrtile.3t       read a raw tile of data
     TIFFReadRGBAImage      rdimage.3t       read an image into a fixed format raster



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IIIINNNNTTTTRRRROOOO((((3333TTTT))))         IIIImmmmaaaaggggeeee FFFFoooorrrrmmmmaaaatttt LLLLiiiibbbbrrrraaaarrrryyyy CCCC++++++++ RRRReeeeffffeeeerrrreeeennnncccceeee MMMMaaaannnnuuuuaaaallll          IIIINNNNTTTTRRRROOOO((((3333TTTT))))



     TIFFReadScanline       readline.3t      read and decode a row of data
     TIFFReadTile           readtile.3t      read and decode a tile of data
     TIFFReverseBits        swab.3t          reverse bits in an array of bytes
     TIFFRGBAImageBegin     rgbaimage.3t     setup decoder state for TIFFRGBAImageGet
     TIFFRGBAImageEnd       rgbaimage.3t     release TIFFRGBAImage decoder state
     TIFFRGBAImageGet       rgbaimage.3t     read and decode an image
     TIFFRGBAImageOK        rgbaimage.3t     is image readable by TIFFRGBAImageGet
     TIFFScanlineSize       size.3t          return size of a scanline
     TIFFSetDirectory       setdir.3t        set the current directory
     TIFFSetSubDirectory    setdir.3t        set the current directory
     TIFFSetErrorHandler    error.3t         set error handler function
     TIFFSetField           setfield.3t      set a tag's value in the current directory
     TIFFSetWarningHandler  error.3t         set warning handler function
     TIFFStripSize          size.3t          return size of a strip
     TIFFSwabShort          swab.3t          swap bytes of short
     TIFFSwabLong           swab.3t          swap bytes of long
     TIFFSwabArrayOfShort   swab.3t          swap bytes of an array of shorts
     TIFFSwabArrayOfLong    swab.3t          swap bytes of an array of longs
     TIFFTileRowSize        size.3t          return size of a row in a tile
     TIFFTileSize           size.3t          return size of a tile
     TIFFVGetField          getfield.3t      return tag value in current directory
     TIFFVGetFieldDefaulted getfield.3t      return tag value in current directory
     TIFFVSetField          setfield.3t      set a tag's value in the current directory
     TIFFWarning            warning.3t       library warning handler
     TIFFWriteDirectory     writedir.3t      write the current directory
     TIFFWriteEncodedStrip  wrestrip.3t      compress and write a strip of data
     TIFFWriteEncodedTile   wretile.3t       compress and write a tile of data
     TIFFWriteRawStrip      wrrstrip.3t      write a raw strip of data
     TIFFWriteRawTile       wrrtile.3t       write a raw tile of data
     TIFFWriteScanline      writeline.3t     write a scanline of data
     TIFFWriteTile          wrrtile.3t       compress and write a tile of data

TTTTAAAAGGGG UUUUSSSSAAAAGGGGEEEE
     The table below lists the TIFF tags that are recognized and handled by
     the library.  If no use is indicated in the table, then the library reads
     and writes the tag, but does not use it internally.  Note that some tags
     are meaningful only when a particular compression scheme is being used;
     e.g.  _G_r_o_u_p_3_O_p_t_i_o_n_s is only useful if _C_o_m_p_r_e_s_s_i_o_n is set to CCITT Group 3
     encoding.  Tags of this sort are considered _c_o_d_e_c-_s_p_e_c_i_f_i_c tags and the
     library does not recognize them except when the _C_o_m_p_r_e_s_s_i_o_n tag has been
     previously set to the relevant compression scheme.
     _T_a_g _N_a_m_e                _V_a_l_u_e  _R/_W  _L_i_b_r_a_r_y _U_s_e/_N_o_t_e_s
     Artist                  315    R/W
     BadFaxLines             326    R/W
     BitsPerSample           258    R/W  lots
     CellLength              265         parsed but ignored
     CellWidth               264         parsed but ignored
     CleanFaxData            327    R/W
     ColorMap                320    R/W
     ColorResponseUnit       300         parsed but ignored
     Compression             259    R/W  choosing codec



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IIIINNNNTTTTRRRROOOO((((3333TTTT))))         IIIImmmmaaaaggggeeee FFFFoooorrrrmmmmaaaatttt LLLLiiiibbbbrrrraaaarrrryyyy CCCC++++++++ RRRReeeeffffeeeerrrreeeennnncccceeee MMMMaaaannnnuuuuaaaallll          IIIINNNNTTTTRRRROOOO((((3333TTTT))))



     ConsecutiveBadFaxLines  328    R/W
     DataType                32996  R    obsoleted by SampleFormat tag
     DateTime                306    R/W
     DocumentName            269    R/W
     DotRange                336    R/W
     ExtraSamples            338    R/W  lots
     FaxRecvParams           34908  R/W
     FaxSubAddress           34909  R/W
     FaxRecvTime             34910  R/W
     FillOrder               266    R/W  control bit order
     FreeByteCounts          289         parsed but ignored
     FreeOffsets             288         parsed but ignored
     GrayResponseCurve       291         parsed but ignored
     GrayResponseUnit        290         parsed but ignored
     Group3Options           292    R/W  used by Group 3 codec
     Group4Options           293    R/W
     HostComputer            316    R/W
     ImageDepth              32997  R/W  tile/strip calculations
     ImageDescription        270    R/W
     ImageLength             257    R/W  lots
     ImageWidth              256    R/W  lots
     InkNames                333    R/W
     InkSet                  332    R/W
     JPEGTables              347    R/W  used by JPEG codec
     Make                    271    R/W
     Matteing                32995  R    obsoleted by ExtraSamples tag
     MaxSampleValue          281    R/W
     MinSampleValue          280    R/W
     Model                   272    R/W
     NewSubFileType          254    R/W  called SubFileType in spec
     NumberOfInks            334    R/W
     Orientation             274    R/W
     PageName                285    R/W
     PageNumber              297    R/W
     PhotometricInterpretation      262  R/Wused by Group 3 and JPEG codecs
     PlanarConfiguration     284    R/W  data i/o
     Predictor               317    R/W  used by LZW and Deflate codecs
     PrimaryChromacities     319    R/W
     ReferenceBlackWhite     532    R/W
     ResolutionUnit          296    R/W  used by Group 3 codec
     RowsPerStrip            278    R/W  data i/o
     SampleFormat            339    R/W
     SamplesPerPixel         277    R/W  lots
     SMinSampleValue         340    R/W
     SMaxSampleValue         341    R/W
     Software                305    R/W
     StripByteCounts         279    R/W  data i/o
     StripOffsets            273    R/W  data i/o
     SubFileType             255    R/W  called OSubFileType in spec
     TargetPrinter           337    R/W
     Thresholding            263    R/W
     TileByteCounts          324    R/W  data i/o



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IIIINNNNTTTTRRRROOOO((((3333TTTT))))         IIIImmmmaaaaggggeeee FFFFoooorrrrmmmmaaaatttt LLLLiiiibbbbrrrraaaarrrryyyy CCCC++++++++ RRRReeeeffffeeeerrrreeeennnncccceeee MMMMaaaannnnuuuuaaaallll          IIIINNNNTTTTRRRROOOO((((3333TTTT))))



     TileDepth               32998  R/W  tile/strip calculations
     TileLength              323    R/W  data i/o
     TileOffsets             324    R/W  data i/o
     TileWidth               322    R/W  data i/o
     TransferFunction        301    R/W
     WhitePoint              318    R/W
     XPosition               286    R/W
     XResolution             282    R/W
     YCbCrCoefficients       529    R/W  used by TIFFRGBAImage support
     YCbCrPositioning        531    R/W  tile/strip size calulcations
     YCbCrSubsampling        530    R/W
     YPosition               286    R/W
     YResolution             283    R/W  used by Group 3 codec

PPPPSSSSEEEEUUUUDDDDOOOO TTTTAAAAGGGGSSSS
     In addition to the normal TIFF tags the library supports a collection of
     tags whose values lie in a range outside the valid range of TIFF tags.
     These tags are termed _p_s_e_u_d-_t_a_g_s and are used to control various codec-
     specific functions within the library.  The table below summarizes the
     defined pseudo-tags.
     _T_a_g _N_a_m_e                _C_o_d_e_c  _R/_W  _L_i_b_r_a_r_y _U_s_e/_N_o_t_e_s
     TIFFTAG_FAXMODE         G3     R/W  general codec operation
     TIFFTAG_FAXFILLFUNC     G3/G4  R/W  bitmap fill function
     TIFFTAG_JPEGQUALITY     JPEG   R/W  compression quality control
     TIFFTAG_JPEGCOLORMODE   JPEG   R/W  control colorspace conversions
     TIFFTAG_JPEGTABLESMODE  JPEG   R/W  control contents of _J_P_E_G_T_a_b_l_e_s tag

     TTTTIIIIFFFFFFFFTTTTAAAAGGGG____FFFFAAAAXXXXMMMMOOOODDDDEEEE
          Control the operation of the Group 3 codec.  Possible values
          (independent bits that can be combined by or'ing them together) are:
          FAXMODE_CLASSIC (enable old-style format in which the RTC is written
          at the end of the last strip), FAXMODE_NORTC (opposite of
          FAXMODE_CLASSIC; also called FAXMODE_CLASSF), FAXMODE_NOEOL (do not
          write EOL codes at the start of each row of data), FAXMODE_BYTEALIGN
          (align each encoded row to an 8-bit boundary), FAXMODE_WORDALIGN
          (align each encoded row to an 16-bit boundary), The default value is
          dependent on the compression scheme; this pseudo-tag is used by the
          various G3 and G4 codecs to share code.

     TTTTIIIIFFFFFFFFTTTTAAAAGGGG____FFFFAAAAXXXXFFFFIIIILLLLLLLLFFFFUUUUNNNNCCCC
          Control the function used to convert arrays of black and white runs
          to packed bit arrays.  This hook can be used to image decoded
          scanlines in multi-bit depth rasters (e.g. for display in colormap
          mode) or for other purposes.  The default value is a pointer to a
          builtin function that images packed bilevel data.

     TTTTIIIIFFFFFFFFTTTTAAAAGGGG____JJJJPPPPEEEEGGGGQQQQUUUUAAAALLLLIIIITTTTYYYY
          Control the compression quality level used in the baseline
          algorithm.  Note that quality levels are in the range 0-100 with a
          default value of 75.




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IIIINNNNTTTTRRRROOOO((((3333TTTT))))         IIIImmmmaaaaggggeeee FFFFoooorrrrmmmmaaaatttt LLLLiiiibbbbrrrraaaarrrryyyy CCCC++++++++ RRRReeeeffffeeeerrrreeeennnncccceeee MMMMaaaannnnuuuuaaaallll          IIIINNNNTTTTRRRROOOO((((3333TTTT))))



     TTTTIIIIFFFFFFFFTTTTAAAAGGGG____JJJJPPPPEEEEGGGGCCCCOOOOLLLLOOOORRRRMMMMOOOODDDDEEEE
          Control whether or not conversion is done between RGB and YCbCr
          colorspaces.  Possible values are:  JPEGCOLORMODE_RAW (do not
          convert), and JPEGCOLORMODE_RGB (convert to/from RGB) The default
          value is JPEGCOLORMODE_RAW.

     TTTTIIIIFFFFFFFFTTTTAAAAGGGG____JJJJPPPPEEEEGGGGTTTTAAAABBBBLLLLEEEESSSSMMMMOOOODDDDEEEE
          Control the information written in the _J_P_E_G_T_a_b_l_e_s tag.  Possible
          values (independent bits that can be combined by or'ing them
          together) are:  JPEGTABLESMODE_QUANT (include quantization tables),
          and JPEGTABLESMODE_HUFF (include Huffman encoding tables).  The
          default value is JPEGTABLESMODE_QUANT|JPEGTABLESMODE_HUFF.

DDDDIIIIAAAAGGGGNNNNOOOOSSSSTTTTIIIICCCCSSSS
     All error messages are directed through the _T_I_F_F_E_r_r_o_r routine.  By
     default messages are directed to ssssttttddddeeeerrrrrrrr in the form:  _m_o_d_u_l_e: _m_e_s_s_a_g_e\_n.
     Warning messages are likewise directed through the _T_I_F_F_W_a_r_n_i_n_g routine.

SSSSEEEEEEEE AAAALLLLSSSSOOOO
     _f_a_x_2_t_i_f_f(1), _g_i_f_2_t_i_f_f(1), _p_a_l_2_r_g_b(1), _p_p_m_2_t_i_f_f(1), _r_g_b_2_y_c_b_c_r(1),
     _r_a_s_2_t_i_f_f(1), _s_g_i_2_t_i_f_f(1), _t_i_f_f_2_b_w(1), _t_i_f_f_d_i_t_h_e_r(1), _t_i_f_f_d_u_m_p(1),
     _t_i_f_f_c_p(1), _t_i_f_f_c_m_p(1), _t_i_f_f_g_t(1), _t_i_f_f_i_n_f_o(1), _t_i_f_f_m_e_d_i_a_n(1),
     _t_i_f_f_s_p_l_i_t(1), _t_i_f_f_s_v(1),

     _T_a_g _I_m_a_g_e _F_i_l_e _F_o_r_m_a_t _S_p_e_c_i_f_i_c_a_t_i_o_n - _R_e_v_i_s_i_o_n _6._0, an Aldus Technical
     Memorandum.

     _T_h_e _S_p_i_r_i_t _o_f _T_I_F_F _C_l_a_s_s _F, an appendix to the TIFF 5.0 specification
     prepared by Cygnet Technologies.

BBBBUUUUGGGGSSSS
     The library does not support multi-sample images where some samples have
     different bits/sample.

     The library does not support random access to compressed data that is
     organized with more than one row per tile or strip.  The library discards
     unknown tags.  The library should do more validity checking of a
     directory's contents.

















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