/*====================================================================* - 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. *====================================================================*/ /* * General features of image I/O in leptonica * * At present, there are 9 file formats for images that can be read * and written: * png (requires libpng, libz) * jpeg (requires libjpeg) * tiff (requires libtiff, libz) * gif (requires libgif) * webp (requires libwebp) * jp2 (requires libopenjp2) * bmp (no library required) * pnm (no library required) * spix (no library required) * Additionally, there are two file formats for writing (only) images: * PostScript (requires libpng, libz, libjpeg, libtiff) * pdf (requires libpng, libz, libjpeg, libtiff) * * For all 9 read/write formats, leptonica provides interconversion * between pix (with raster data) and formatted image data: * Conversion from pix (typically compression): * pixWrite(): pix --> file * pixWriteStream(): pix --> filestream (aka FILE*) * pixWriteMem(): pix --> memory buffer * Conversion to pix (typically decompression): * pixRead(): file --> pix * pixReadStream(): filestream --> pix * pixReadMem(): memory buffer --> pix * * Conversions for which the image data is not compressed are: * * uncompressed tiff (IFF_TIFF) * * bmp * * pnm * * spix (fast serialization that copies the pix raster data) * * The image header (metadata) information can be read from either * the compressed file or a memory buffer, for all 9 formats. */ #ifndef LEPTONICA_IMAGEIO_H #define LEPTONICA_IMAGEIO_H /* ------------------ Image file format types -------------- */ /* * The IFF_DEFAULT flag is used to write the file out in the * same (input) file format that the pix was read from. If the pix * was not read from file, the input format field will be * IFF_UNKNOWN and the output file format will be chosen to * be compressed and lossless; namely, IFF_TIFF_G4 for d = 1 * and IFF_PNG for everything else. IFF_JP2 is for jpeg2000, which * is not supported in leptonica. * * In the future, new format types that have defined extensions * will be added before IFF_DEFAULT, and will be kept in sync with * the file format extensions in writefile.c. The positions of * file formats before IFF_DEFAULT will remain invariant. */ enum { IFF_UNKNOWN = 0, IFF_BMP = 1, IFF_JFIF_JPEG = 2, IFF_PNG = 3, IFF_TIFF = 4, IFF_TIFF_PACKBITS = 5, IFF_TIFF_RLE = 6, IFF_TIFF_G3 = 7, IFF_TIFF_G4 = 8, IFF_TIFF_LZW = 9, IFF_TIFF_ZIP = 10, IFF_PNM = 11, IFF_PS = 12, IFF_GIF = 13, IFF_JP2 = 14, IFF_WEBP = 15, IFF_LPDF = 16, IFF_DEFAULT = 17, IFF_SPIX = 18 }; /* ---------------------- Format header ids --------------------- */ enum { BMP_ID = 0x4d42, TIFF_BIGEND_ID = 0x4d4d, /* MM - for 'motorola' */ TIFF_LITTLEEND_ID = 0x4949 /* II - for 'intel' */ }; /* ------------- Hinting bit flags in jpeg reader --------------- */ enum { L_JPEG_READ_LUMINANCE = 1, /* only want luminance data; no chroma */ L_JPEG_FAIL_ON_BAD_DATA = 2 /* don't return possibly damaged pix */ }; /* ------------------ Pdf formated encoding types --------------- */ enum { L_JPEG_ENCODE = 1, /* use dct encoding: 8 and 32 bpp, no cmap */ L_G4_ENCODE = 2, /* use ccitt g4 fax encoding: 1 bpp */ L_FLATE_ENCODE = 3, /* use flate encoding: any depth, cmap ok */ L_JP2K_ENCODE = 4 /* use jp2k encoding: 8 and 32 bpp, no cmap */ }; /* ------------------ Compressed image data --------------------- */ /* * In use, either datacomp or data85 will be produced, depending * on whether the data needs to be ascii85 encoded. PostScript * requires ascii85 encoding; pdf does not. * * For the colormap (flate compression only), PostScript uses ascii85 * encoding and pdf uses a bracketed array of space-separated * hex-encoded rgb triples. Only tiff g4 (type == L_G4_ENCODE) uses * the minisblack field. */ struct L_Compressed_Data { l_int32 type; /* encoding type: L_JPEG_ENCODE, etc */ l_uint8 *datacomp; /* gzipped raster data */ size_t nbytescomp; /* number of compressed bytes */ char *data85; /* ascii85-encoded gzipped raster data */ size_t nbytes85; /* number of ascii85 encoded bytes */ char *cmapdata85; /* ascii85-encoded uncompressed cmap */ char *cmapdatahex; /* hex pdf array for the cmap */ l_int32 ncolors; /* number of colors in cmap */ l_int32 w; /* image width */ l_int32 h; /* image height */ l_int32 bps; /* bits/sample; typ. 1, 2, 4 or 8 */ l_int32 spp; /* samples/pixel; typ. 1 or 3 */ l_int32 minisblack; /* tiff g4 photometry */ l_int32 predictor; /* flate data has PNG predictors */ size_t nbytes; /* number of uncompressed raster bytes */ l_int32 res; /* resolution (ppi) */ }; typedef struct L_Compressed_Data L_COMP_DATA; /* ------------------------ Pdf multi-image flags ------------------------ */ enum { L_FIRST_IMAGE = 1, /* first image to be used */ L_NEXT_IMAGE = 2, /* intermediate image; not first or last */ L_LAST_IMAGE = 3 /* last image to be used */ }; /* ------------------ Intermediate pdf generation data -------------------- */ /* * This accumulates data for generating a pdf of a single page consisting * of an arbitrary number of images. * * None of the strings have a trailing newline. */ struct L_Pdf_Data { char *title; /* optional title for pdf */ l_int32 n; /* number of images */ l_int32 ncmap; /* number of colormaps */ struct L_Ptra *cida; /* array of compressed image data */ char *id; /* %PDF-1.2 id string */ char *obj1; /* catalog string */ char *obj2; /* metadata string */ char *obj3; /* pages string */ char *obj4; /* page string (variable data) */ char *obj5; /* content string (variable data) */ char *poststream; /* post-binary-stream string */ char *trailer; /* trailer string (variable data) */ struct Pta *xy; /* store (xpt, ypt) array */ struct Pta *wh; /* store (wpt, hpt) array */ struct Box *mediabox; /* bounding region for all images */ struct Sarray *saprex; /* pre-binary-stream xobject strings */ struct Sarray *sacmap; /* colormap pdf object strings */ struct L_Dna *objsize; /* sizes of each pdf string object */ struct L_Dna *objloc; /* location of each pdf string object */ l_int32 xrefloc; /* location of xref */ }; typedef struct L_Pdf_Data L_PDF_DATA; #endif /* LEPTONICA_IMAGEIO_H */