00001 /** \file
00002  * \brief File Access
00003  *
00004  * See Copyright Notice in im_lib.h
00005  * $Id: im_file.h,v 1.2 2005/08/10 02:12:16 scuri Exp $
00006  */
00007 
00008 #ifndef __IM_FILE_H
00009 #define __IM_FILE_H
00010 
00011 #include "im.h"
00012 
00013 #if defined(__cplusplus)
00014 extern "C" {
00015 #endif
00016 
00017 
00018 /** \defgroup filesdk File Format SDK
00019  * \par
00020  * All the file formats are based on theses structures. Use them to create new file formats. \n
00021  * The LineBuffer functions will help transfer image from format buffer to application buffer and vice-versa.
00022  * \par
00023  * See \ref im_file.h
00024  * \ingroup file */
00025 
00026 
00027 /** \brief Image File Format Base (SDK Use Only)
00028  *
00029  * \par
00030  * Base container to hold format independent state variables.
00031  * \ingroup filesdk */
00032 struct _imFile
00033 {
00034   int is_new;
00035   void* attrib_table;    /**< in fact is a imAttribTable, but we hide this here */
00036 
00037   void* line_buffer;     /**< used for line convertion, contains all components if packed, or only one if not */
00038   int line_buffer_size;
00039   int line_buffer_extra; /**< extra bytes to be allocated */
00040   int line_buffer_alloc; /**< total allocated so far */
00041   int counter;
00042 
00043   int convert_bpp;       /**< number of bpp to unpack/pack to/from 1 byte. 
00044                               When reading converts n packed bits to 1 byte (unpack). If n>1 will also expand to 0-255. 
00045                               When writing converts 1 byte to 1 bit (pack). 
00046                               If negative will only expand to 0-255 (no unpack or pack). */
00047   int switch_type;       /**< flag to switch the original data type: char-byte, short-ushort, uint-int, double-float */
00048 
00049   long palette[256];
00050   int palette_count;
00051 
00052   int user_color_mode,
00053       user_data_type,
00054       file_color_mode,   /* these two must be filled by te driver always. */
00055       file_data_type;
00056 
00057   /* these must be filled by the driver when reading,
00058      and given by the user when writing. */
00059 
00060   char compression[10];
00061   int image_count,
00062       image_index,
00063       width,           
00064       height;
00065 };
00066 
00067 
00068 /* Internal Use only */
00069 
00070 /* Initializes the imFile structure.
00071  * Used by the special format RAW. */
00072 void imFileClear(imFile* ifile);
00073 
00074 /* Initializes the line buffer.
00075  * Used by "im_file.cpp" only. */
00076 void imFileLineBufferInit(imFile* ifile);
00077 
00078 /* Check if the conversion is valid.
00079  * Used by "im_file.cpp" only. */
00080 int imFileCheckConversion(imFile* ifile);
00081 
00082 
00083 
00084 /* File Format SDK */
00085 
00086 /** Number of lines to be accessed.
00087  * \ingroup filesdk */
00088 int imFileLineBufferCount(imFile* ifile);
00089 
00090 /** Increments the row and plane counters.
00091  * \ingroup filesdk */
00092 void imFileLineBufferInc(imFile* ifile, int *row, int *plane);
00093 
00094 /** Converts from FILE color mode to USER color mode.
00095  * \ingroup filesdk */
00096 void imFileLineBufferRead(imFile* ifile, void* data, int line, int plane);
00097 
00098 /** Converts from USER color mode to FILE color mode.
00099  * \ingroup filesdk */
00100 void imFileLineBufferWrite(imFile* ifile, const void* data, int line, int plane);
00101 
00102 /** Utility to calculate the line size in byte with a specified alignment. \n
00103  * "align" can be 1, 2 or 4.
00104  * \ingroup filesdk */
00105 int imFileLineSizeAligned(int width, int bpp, int align);
00106 
00107 
00108 #if defined(__cplusplus)
00109 }
00110 #endif
00111 
00112 #endif