tjpgd.h

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/*----------------------------------------------------------------------------/
/ TJpgDec - Tiny JPEG Decompressor R0.03 include file         (C)ChaN, 2021
/----------------------------------------------------------------------------*/
#ifndef DEF_TJPGDEC
#define DEF_TJPGDEC
 
// Include standard library headers outside namespace to avoid conflicts
#include "fl/stl/string.h"
#include "fl/stl/stdint.h"
#include "fl/stl/noexcept.h"
#include "tjpgdcnf.h"
 
namespace fl {
namespace third_party {
 
#if JD_FASTDECODE >= 1
typedef int16_t jd_yuv_t;
#else
typedef uint8_t jd_yuv_t;
#endif
 
 
/* Error code */
typedef enum {
    JDR_OK = 0,   /* 0: Succeeded */
    JDR_INTR,   /* 1: Interrupted by output function */ 
    JDR_INP, /* 2: Device error or wrong termination of input stream */
    JDR_MEM1,   /* 3: Insufficient memory pool for the image */
    JDR_MEM2,   /* 4: Insufficient stream input buffer */
    JDR_PAR, /* 5: Parameter error */
    JDR_FMT1,   /* 6: Data format error (may be broken data) */
    JDR_FMT2,   /* 7: Right format but not supported */
    JDR_FMT3    /* 8: Not supported JPEG standard */
} JRESULT;
 
 
 
/* Rectangular region in the output image */
typedef struct {
    uint16_t left;      /* Left end */
    uint16_t right;        /* Right end */
    uint16_t top;        /* Top end */
    uint16_t bottom;  /* Bottom end */
} JRECT;
 
 
 
/* Decompressor object structure */
typedef struct JDEC JDEC;
struct JDEC {
    size_t dctr;                /* Number of bytes available in the input buffer */
    uint8_t* dptr;               /* Current data read ptr */
    uint8_t* inbuf;             /* Bit stream input buffer */
    uint8_t dbit;                /* Number of bits availavble in wreg or reading bit mask */
    uint8_t scale;              /* Output scaling ratio */
    uint8_t msx, msy;          /* MCU size in unit of block (width, height) */
    uint8_t qtid[3];         /* Quantization table ID of each component, Y, Cb, Cr */
    uint8_t ncomp;              /* Number of color components 1:grayscale, 3:color */
    int16_t dcv[3];               /* Previous DC element of each component */
    uint16_t nrst;              /* Restart inverval */
    uint16_t width, height;      /* Size of the input image (pixel) */
    uint8_t* huffbits[2][2]; /* Huffman bit distribution tables [id][dcac] */
    uint16_t* huffcode[2][2];   /* Huffman code word tables [id][dcac] */
    uint8_t* huffdata[2][2]; /* Huffman decoded data tables [id][dcac] */
    int32_t* qttbl[4];          /* Dequantizer tables [id] */
#if JD_FASTDECODE >= 1
    uint32_t wreg;              /* Working shift register */
    uint8_t marker;              /* Detected marker (0:None) */
#if JD_FASTDECODE == 2
    uint8_t longofs[2][2];       /* Table offset of long code [id][dcac] */
    uint16_t* hufflut_ac[2];    /* Fast huffman decode tables for AC short code [id] */
    uint8_t* hufflut_dc[2];      /* Fast huffman decode tables for DC short code [id] */
#endif
#endif
    void* workbuf;               /* Working buffer for IDCT and RGB output */
    jd_yuv_t* mcubuf;         /* Working buffer for the MCU */
    void* pool;                 /* Pointer to available memory pool */
    size_t sz_pool;              /* Size of momory pool (bytes available) */
    size_t (*infunc)(JDEC*, uint8_t*, size_t); /* Pointer to jpeg stream input function */
    void* device;             /* Pointer to I/O device identifiler for the session */
    uint8_t swap;       /* Added by Bodmer to control byte swapping */
};
 
/* Extended decoder state for progressive processing */
struct JDEC_Progressive {
    JDEC base;                  /* Original decoder state */
 
    /* Progressive state */
    uint16_t current_mcu_x;        /* Current MCU position X */
    uint16_t current_mcu_y;        /* Current MCU position Y */
    uint16_t mcus_processed;  /* MCUs completed so far */
    uint16_t total_mcus;      /* Total MCUs in image */
 
    /* Suspension/Resume support */
    uint8_t is_suspended;        /* Can be suspended between MCUs */
    uint8_t suspend_reason;        /* Why suspended (data/time/callback) */
 
    /* Buffer state preservation */
    size_t stream_position;      /* Current stream read position */
    uint8_t bit_buffer_state;    /* Partial bit decoding state */
    uint32_t partial_bits;      /* Bits waiting to be processed */
 
    /* Memory management */
    void* persistent_workspace; /* Workspace that survives suspend/resume */
    uint8_t workspace_initialized; /* Track initialization state */
};
 
 
 
/* TJpgDec API functions */
JRESULT jd_prepare (JDEC* jd, size_t (*infunc)(JDEC*,uint8_t*,size_t), void* pool, size_t sz_pool, void* dev) FL_NOEXCEPT;
JRESULT jd_decomp (JDEC* jd, int (*outfunc)(JDEC*,void*,JRECT*), uint8_t scale) FL_NOEXCEPT;
 
/* Progressive decompression API */
enum { JDR_SUSPEND = 9 };  /* Suspended for progressive processing */
 
JRESULT jd_decomp_progressive(
    JDEC_Progressive* jpd,                     /* Progressive decoder state */
    int (*outfunc)(JDEC*, void*, JRECT*),      /* Output callback */
    uint8_t scale,                             /* Scaling factor */
    uint16_t max_mcus_per_call,                /* MCU processing limit per call */
    uint8_t* more_data_needed,                 /* Output: needs more input data */
    uint8_t* processing_complete               /* Output: decode finished */
) FL_NOEXCEPT;
 
} // namespace third_party
} // namespace fl
 
#endif /* _TJPGDEC */