00001 /** \file
00002  * \brief File Access
00003  *
00004  * See Copyright Notice in im_lib.h
00005  */
00006 
00007 #ifndef __IM_FILE_H
00008 #define __IM_FILE_H
00009 
00010 #include "im.h"
00011 
00012 #if defined(__cplusplus)
00013 extern "C" {
00014 #endif
00015 
00016 
00017 /** \defgroup filesdk File Format SDK
00018  * \par
00019  * All the file formats are based on theses structures. Use them to create new file formats. \n
00020  * The LineBuffer functions will help transfer image from format buffer to application buffer and vice-versa.
00021  * \par
00022  * See \ref im_file.h
00023  * \ingroup file */
00024 
00025 
00026 /** \brief Image File Format Base (SDK Use Only)
00027  *
00028  * \par
00029  * Base container to hold format independent state variables.
00030  * \ingroup filesdk */
00031 struct _imFile
00032 {
00033   int is_new;
00034   void* attrib_table;    /**< in fact is a imAttribTable, but we hide this here */
00035 
00036   void* line_buffer;     /**< used for line convertion, contains all components if packed, or only one if not */
00037   int line_buffer_size;
00038   int line_buffer_extra; /**< extra bytes to be allocated */
00039   int line_buffer_alloc; /**< total allocated so far */
00040   int counter;
00041 
00042   int convert_bpp;       /**< number of bpp to unpack/pack to/from 1 byte. 
00043                               When reading converts n packed bits to 1 byte (unpack). If n>1 will also expand to 0-255. 
00044                               When writing converts 1 byte to 1 bit (pack). 
00045                               If negative will only expand to 0-255 (no unpack or pack). */
00046   int switch_type;       /**< flag to switch the original data type: char-byte, short-ushort, uint-int, double-float */
00047 
00048   long palette[256];
00049   int palette_count;
00050 
00051   int user_color_mode,
00052       user_data_type,
00053       file_color_mode,   /* these two must be filled by te driver always. */
00054       file_data_type;
00055 
00056   /* these must be filled by the driver when reading,
00057      and given by the user when writing. */
00058 
00059   char compression[10];
00060   int image_count,
00061       image_index,
00062       width,           
00063       height;
00064 };
00065 
00066 
00067 /* Internal Use only */
00068 
00069 /* Initializes the imFile structure.
00070  * Used by the special format RAW. */
00071 void imFileClear(imFile* ifile);
00072 
00073 /* Initializes the line buffer.
00074  * Used by "im_file.cpp" only. */
00075 void imFileLineBufferInit(imFile* ifile);
00076 
00077 /* Check if the conversion is valid.
00078  * Used by "im_file.cpp" only. */
00079 int imFileCheckConversion(imFile* ifile);
00080 
00081 
00082 
00083 /* File Format SDK */
00084 
00085 /** Number of lines to be accessed.
00086  * \ingroup filesdk */
00087 int imFileLineBufferCount(imFile* ifile);
00088 
00089 /** Increments the row and plane counters.
00090  * \ingroup filesdk */
00091 void imFileLineBufferInc(imFile* ifile, int *row, int *plane);
00092 
00093 /** Converts from FILE color mode to USER color mode.
00094  * \ingroup filesdk */
00095 void imFileLineBufferRead(imFile* ifile, void* data, int line, int plane);
00096 
00097 /** Converts from USER color mode to FILE color mode.
00098  * \ingroup filesdk */
00099 void imFileLineBufferWrite(imFile* ifile, const void* data, int line, int plane);
00100 
00101 /** Utility to calculate the line size in byte with a specified alignment. \n
00102  * "align" can be 1, 2 or 4.
00103  * \ingroup filesdk */
00104 int imFileLineSizeAligned(int width, int bpp, int align);
00105 
00106 
00107 #if defined(__cplusplus)
00108 }
00109 #endif
00110 
00111 #endif