TinyJpgDec.h

00001 /*----------------------------------------------------------------------------/
00002 / TJpgDec - Tiny JPEG Decompressor include file               (C)ChaN, 2012
00003 /----------------------------------------------------------------------------*/
00004 #ifndef _TJPGDEC
00005 #define _TJPGDEC
00006 /*---------------------------------------------------------------------------*/
00007 /* System Configurations */
00008 
00009 #define JD_SZBUF        1024 /* Size of stream input buffer */
00010 #define JD_FORMAT       0   /* Output pixel format 0:RGB888 (3 BYTE/pix), 1:RGB565 (1 WORD/pix) */
00011 #define JD_USE_SCALE    1   /* Use descaling feature for output */
00012 #define JD_TBLCLIP      1   /* Use table for saturation (might be a bit faster but increases 1K bytes of code size) */
00013 
00014 /*---------------------------------------------------------------------------*/
00015 
00016 #ifdef __cplusplus
00017 extern "C" {
00018 #endif
00019 
00020 #include "integer.h"
00021 
00022 
00023     /* Error code */
00024     typedef enum {
00025         JDR_OK = 0, /* 0: Succeeded */
00026         JDR_INTR,   /* 1: Interrupted by output function */
00027         JDR_INP,    /* 2: Device error or wrong termination of input stream */
00028         JDR_MEM1,   /* 3: Insufficient memory pool for the image */
00029         JDR_MEM2,   /* 4: Insufficient stream input buffer */
00030         JDR_PAR,    /* 5: Parameter error */
00031         JDR_FMT1,   /* 6: Data format error (may be damaged data) */
00032         JDR_FMT2,   /* 7: Right format but not supported */
00033         JDR_FMT3    /* 8: Not supported JPEG standard */
00034     }
00035     JRESULT;
00036 
00037 
00038 
00039     /* Rectangular structure */
00040     typedef struct {
00041         WORD left, right, top, bottom;
00042     } JRECT;
00043 
00044 
00045 
00046     /* Decompressor object structure */
00047     typedef struct JDEC JDEC;
00048     struct JDEC {
00049         JPG_UINT dctr;              /* Number of bytes available in the input buffer */
00050         BYTE* dptr;             /* Current data read ptr */
00051         BYTE* inbuf;            /* Bit stream input buffer */
00052         BYTE dmsk;              /* Current bit in the current read byte */
00053         BYTE scale;             /* Output scaling ratio */
00054         BYTE msx, msy;          /* MCU size in unit of block (width, height) */
00055         BYTE qtid[3];           /* Quantization table ID of each component */
00056         SHORT dcv[3];           /* Previous DC element of each component */
00057         WORD nrst;              /* Restart inverval */
00058         JPG_UINT width, height;     /* Size of the input image (pixel) */
00059         BYTE* huffbits[2][2];   /* Huffman bit distribution tables [id][dcac] */
00060         WORD* huffcode[2][2];   /* Huffman code word tables [id][dcac] */
00061         BYTE* huffdata[2][2];   /* Huffman decoded data tables [id][dcac] */
00062         LONG* qttbl[4];         /* Dequaitizer tables [id] */
00063         void* workbuf;          /* Working buffer for IDCT and RGB output */
00064         BYTE* mcubuf;           /* Working buffer for the MCU */
00065         void* pool;             /* Pointer to available memory pool */
00066         JPG_UINT sz_pool;           /* Size of momory pool (bytes available) */
00067         JPG_UINT (*infunc)(JDEC*, BYTE*, JPG_UINT);/* Pointer to jpeg stream input function */
00068         void* device;           /* Pointer to I/O device identifiler for the session */
00069     };
00070 
00071 
00072 
00073     /* TJpgDec API functions */
00074     JRESULT jd_prepare (JDEC*, JPG_UINT(*)(JDEC*,BYTE*,JPG_UINT), void*, JPG_UINT, void*);
00075     JRESULT jd_decomp (JDEC*, JPG_UINT(*)(JDEC*,void*,JRECT*), BYTE);
00076 
00077 
00078 #ifdef __cplusplus
00079 }
00080 #endif
00081 
00082 #endif /* _TJPGDEC */