text: /*
   * jpeglib.h
   *
   * This file was part of the Independent JPEG Group's software:
   * Copyright (C) 1991-1998, Thomas G. Lane.
   * Modified 2002-2009 by Guido Vollbeding.
   * libjpeg-turbo Modifications:
   * Copyright (C) 2009-2011, 2013-2014, 2016-2017, D. R. Commander.
   * Copyright (C) 2015, Google, Inc.
   * For conditions of distribution and use, see the accompanying README.ijg
   * file.
   *
   * This file defines the application interface for the JPEG library.
   * Most applications using the library need only include this file,
   * and perhaps jerror.h if they want to know the exact error codes.
   */
  
  #ifndef JPEGLIB_H
  #define JPEGLIB_H
  
  /*
   * First we include the configuration files that record how this
   * installation of the JPEG library is set up.  jconfig.h can be
   * generated automatically for many systems.  jmorecfg.h contains
   * manual configuration options that most people need not worry about.
   */
  
  #ifndef JCONFIG_INCLUDED        /* in case jinclude.h already did */
  #include "jconfig.h"            /* widely used configuration options */
  #endif
  #include "jmorecfg.h"           /* seldom changed options */
  
  
  #ifdef __cplusplus
  #ifndef DONT_USE_EXTERN_C
  extern "C" {
  #endif
  #endif
  
  
  /* Various constants determining the sizes of things.
   * All of these are specified by the JPEG standard, so don't change them
   * if you want to be compatible.
   */
  
  #define DCTSIZE             8   /* The basic DCT block is 8x8 samples */
  #define DCTSIZE2            64  /* DCTSIZE squared; # of elements in a block */
  #define NUM_QUANT_TBLS      4   /* Quantization tables are numbered 0..3 */
  #define NUM_HUFF_TBLS       4   /* Huffman tables are numbered 0..3 */
  #define NUM_ARITH_TBLS      16  /* Arith-coding tables are numbered 0..15 */
  #define MAX_COMPS_IN_SCAN   4   /* JPEG limit on # of components in one scan */
  #define MAX_SAMP_FACTOR     4   /* JPEG limit on sampling factors */
  /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
   * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
   * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
   * to handle it.  We even let you do this from the jconfig.h file.  However,
   * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
   * sometimes emits noncompliant files doesn't mean you should too.
   */
  #define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
  #ifndef D_MAX_BLOCKS_IN_MCU
  #define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
  #endif
  
  
  /* Data structures for images (arrays of samples and of DCT coefficients).
   */
  
  typedef JSAMPLE *JSAMPROW;      /* ptr to one image row of pixel samples. */
  typedef JSAMPROW *JSAMPARRAY;   /* ptr to some rows (a 2-D sample array) */
  typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
  
  typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
  typedef JBLOCK *JBLOCKROW;      /* pointer to one row of coefficient blocks */
  typedef JBLOCKROW *JBLOCKARRAY;         /* a 2-D array of coefficient blocks */
  typedef JBLOCKARRAY *JBLOCKIMAGE;       /* a 3-D array of coefficient blocks */
  
  typedef JCOEF *JCOEFPTR;        /* useful in a couple of places */
  
  
  /* Types for JPEG compression parameters and working tables. */
  
  
  /* DCT coefficient quantization tables. */
  
  typedef struct {
    /* This array gives the coefficient quantizers in natural array order
     * (not the zigzag order in which they are stored in a JPEG DQT marker).
     * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
     */
    UINT16 quantval[DCTSIZE2];    /* quantization step for each coefficient */
    /* This field is used only during compression.  It's initialized FALSE when
     * the table is created, and set TRUE when it's been output to the file.
     * You could suppress output of a table by setting this to TRUE.
     * (See jpeg_suppress_tables for an example.)
     */
    boolean sent_table;           /* TRUE when table has been output */
  } JQUANT_TBL;
  
  
  /* Huffman coding tables. */
  
  typedef struct {
    /* These two fields directly represent the contents of a JPEG DHT marker */
    UINT8 bits[17];               /* bits[k] = # of symbols with codes of */
                                  /* length k bits; bits[0] is unused */
    UINT8 huffval[256];           /* The symbols, in order of incr code length */
    /* This field is used only during compression.  It's initialized FALSE when
     * the table is created, and set TRUE when it's been output to the file.
     * You could suppress output of a table by setting this to TRUE.
     * (See jpeg_suppress_tables for an example.)
     */
    boolean sent_table;           /* TRUE when table has been output */
  } JHUFF_TBL;
  
  
  /* Basic info about one component (color channel). */
  
  typedef struct {
    /* These values are fixed over the whole image. */
    /* For compression, they must be supplied by parameter setup; */
    /* for decompression, they are read from the SOF marker. */
    int component_id;             /* identifier for this component (0..255) */
    int component_index;          /* its index in SOF or cinfo->comp_info[] */
    int h_samp_factor;            /* horizontal sampling factor (1..4) */
    int v_samp_factor;            /* vertical sampling factor (1..4) */
    int quant_tbl_no;             /* quantization table selector (0..3) */
    /* These values may vary between scans. */
    /* For compression, they must be supplied by parameter setup; */
    /* for decompression, they are read from the SOS marker. */
    /* The decompressor output side may not use these variables. */
    int dc_tbl_no;                /* DC entropy table selector (0..3) */
    int ac_tbl_no;                /* AC entropy table selector (0..3) */
  
    /* Remaining fields should be treated as private by applications. */
  
    /* These values are computed during compression or decompression startup: */
    /* Component's size in DCT blocks.
     * Any dummy blocks added to complete an MCU are not counted; therefore
     * these values do not depend on whether a scan is interleaved or not.
     */
    JDIMENSION width_in_blocks;
    JDIMENSION height_in_blocks;
    /* Size of a DCT block in samples.  Always DCTSIZE for compression.
     * For decompression this is the size of the output from one DCT block,
     * reflecting any scaling we choose to apply during the IDCT step.
     * Values from 1 to 16 are supported.
     * Note that different components may receive different IDCT scalings.
     */
  #if JPEG_LIB_VERSION >= 70
    int DCT_h_scaled_size;
    int DCT_v_scaled_size;
  #else
    int DCT_scaled_size;
  #endif
    /* The downsampled dimensions are the component's actual, unpadded number
     * of samples at the main buffer (preprocessing/compression interface), thus
     * downsampled_width = ceil(image_width * Hi/Hmax)
     * and similarly for height.  For decompression, IDCT scaling is included, so
     * downsampled_width = ceil(image_width * Hi/Hmax * DCT_[h_]scaled_size/DCTSIZE)
     */
    JDIMENSION downsampled_width;  /* actual width in samples */
    JDIMENSION downsampled_height; /* actual height in samples */
    /* This flag is used only for decompression.  In cases where some of the
     * components will be ignored (eg grayscale output from YCbCr image),
     * we can skip most computations for the unused components.
     */
    boolean component_needed;     /* do we need the value of this component? */
  
    /* These values are computed before starting a scan of the component. */
    /* The decompressor output side may not use these variables. */
    int MCU_width;                /* number of blocks per MCU, horizontally */
    int MCU_height;               /* number of blocks per MCU, vertically */
    int MCU_blocks;               /* MCU_width * MCU_height */
    int MCU_sample_width;         /* MCU width in samples, MCU_width*DCT_[h_]scaled_size */
    int last_col_width;           /* # of non-dummy blocks across in last MCU */
    int last_row_height;          /* # of non-dummy blocks down in last MCU */
  
    /* Saved quantization table for component; NULL if none yet saved.
     * See jdinput.c comments about the need for this information.
     * This field is currently used only for decompression.
     */
    JQUANT_TBL *quant_table;
  
    /* Private per-component storage for DCT or IDCT subsystem. */
    void *dct_table;
  } jpeg_component_info;
  
  
  /* The script for encoding a multiple-scan file is an array of these: */
  
  typedef struct {
    int comps_in_scan;            /* number of components encoded in this scan */
    int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
    int Ss, Se;                   /* progressive JPEG spectral selection parms */
    int Ah, Al;                   /* progressive JPEG successive approx. parms */
  } jpeg_scan_info;
  
  /* The decompressor can save APPn and COM markers in a list of these: */
  
  typedef struct jpeg_marker_struct *jpeg_saved_marker_ptr;
  
  struct jpeg_marker_struct {
    jpeg_saved_marker_ptr next;   /* next in list, or NULL */
    UINT8 marker;                 /* marker code: JPEG_COM, or JPEG_APP0+n */
    unsigned int original_length; /* # bytes of data in the file */
    unsigned int data_length;     /* # bytes of data saved at data[] */
    JOCTET *data;                 /* the data contained in the marker */
    /* the marker length word is not counted in data_length or original_length */
  };
  
  /* Known color spaces. */
  
  #define JCS_EXTENSIONS  1
  #define JCS_ALPHA_EXTENSIONS  1
  
  typedef enum {
    JCS_UNKNOWN,            /* error/unspecified */
    JCS_GRAYSCALE,          /* monochrome */
    JCS_RGB,                /* red/green/blue as specified by the RGB_RED,
                               RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros */
    JCS_YCbCr,              /* Y/Cb/Cr (also known as YUV) */
    JCS_CMYK,               /* C/M/Y/K */
    JCS_YCCK,               /* Y/Cb/Cr/K */
    JCS_EXT_RGB,            /* red/green/blue */
    JCS_EXT_RGBX,           /* red/green/blue/x */
    JCS_EXT_BGR,            /* blue/green/red */
    JCS_EXT_BGRX,           /* blue/green/red/x */
    JCS_EXT_XBGR,           /* x/blue/green/red */
    JCS_EXT_XRGB,           /* x/red/green/blue */
    /* When out_color_space it set to JCS_EXT_RGBX, JCS_EXT_BGRX, JCS_EXT_XBGR,
       or JCS_EXT_XRGB during decompression, the X byte is undefined, and in
       order to ensure the best performance, libjpeg-turbo can set that byte to
       whatever value it wishes.  Use the following colorspace constants to
       ensure that the X byte is set to 0xFF, so that it can be interpreted as an
       opaque alpha channel. */
    JCS_EXT_RGBA,           /* red/green/blue/alpha */
    JCS_EXT_BGRA,           /* blue/green/red/alpha */
    JCS_EXT_ABGR,           /* alpha/blue/green/red */
    JCS_EXT_ARGB,           /* alpha/red/green/blue */
    JCS_RGB565              /* 5-bit red/6-bit green/5-bit blue */
  } J_COLOR_SPACE;
  
  /* DCT/IDCT algorithm options. */
  
  typedef enum {
    JDCT_ISLOW,             /* slow but accurate integer algorithm */
    JDCT_IFAST,             /* faster, less accurate integer method */
    JDCT_FLOAT              /* floating-point: accurate, fast on fast HW */
  } J_DCT_METHOD;
  
  #ifndef JDCT_DEFAULT            /* may be overridden in jconfig.h */
  #define JDCT_DEFAULT  JDCT_ISLOW
  #endif
  #ifndef JDCT_FASTEST            /* may be overridden in jconfig.h */
  #define JDCT_FASTEST  JDCT_IFAST
  #endif
  
  /* Dithering options for decompression. */
  
  typedef enum {
    JDITHER_NONE,           /* no dithering */
    JDITHER_ORDERED,        /* simple ordered dither */
    JDITHER_FS              /* Floyd-Steinberg error diffusion dither */
  } J_DITHER_MODE;
  
  
  /* Common fields between JPEG compression and decompression master structs. */
  
  #define jpeg_common_fields \
    struct jpeg_error_mgr *err;   /* Error handler module */ \
    struct jpeg_memory_mgr *mem;  /* Memory manager module */ \
    struct jpeg_progress_mgr *progress; /* Progress monitor, or NULL if none */ \
    void *client_data;            /* Available for use by application */ \
    boolean is_decompressor;      /* So common code can tell which is which */ \
    int global_state              /* For checking call sequence validity */
  
  /* Routines that are to be used by both halves of the library are declared
   * to receive a pointer to this structure.  There are no actual instances of
   * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
   */
  struct jpeg_common_struct {
    jpeg_common_fields;           /* Fields common to both master struct types */
    /* Additional fields follow in an actual jpeg_compress_struct or
     * jpeg_decompress_struct.  All three structs must agree on these
     * initial fields!  (This would be a lot cleaner in C++.)
     */
  };
  
  typedef struct jpeg_common_struct *j_common_ptr;
  typedef struct jpeg_compress_struct *j_compress_ptr;
  typedef struct jpeg_decompress_struct *j_decompress_ptr;
  
  
  /* Master record for a compression instance */
  
  struct jpeg_compress_struct {
    jpeg_common_fields;           /* Fields shared with jpeg_decompress_struct */
  
    /* Destination for compressed data */
    struct jpeg_destination_mgr *dest;
  
    /* Description of source image --- these fields must be filled in by
     * outer application before starting compression.  in_color_space must
     * be correct before you can even call jpeg_set_defaults().
     */
  
    JDIMENSION image_width;       /* input image width */
    JDIMENSION image_height;      /* input image height */
    int input_components;         /* # of color components in input image */
    J_COLOR_SPACE in_color_space; /* colorspace of input image */
  
    double input_gamma;           /* image gamma of input image */
  
    /* Compression parameters --- these fields must be set before calling
     * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to
     * initialize everything to reasonable defaults, then changing anything
     * the application specifically wants to change.  That way you won't get
     * burnt when new parameters are added.  Also note that there are several
     * helper routines to simplify changing parameters.
     */
  
  #if JPEG_LIB_VERSION >= 70
    unsigned int scale_num, scale_denom; /* fraction by which to scale image */
  
    JDIMENSION jpeg_width;        /* scaled JPEG image width */
    JDIMENSION jpeg_height;       /* scaled JPEG image height */
    /* Dimensions of actual JPEG image that will be written to file,
     * derived from input dimensions by scaling factors above.
     * These fields are computed by jpeg_start_compress().
     * You can also use jpeg_calc_jpeg_dimensions() to determine these values
     * in advance of calling jpeg_start_compress().
     */
  #endif
  
    int data_precision;           /* bits of precision in image data */
  
    int num_components;           /* # of color components in JPEG image */
    J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
  
    jpeg_component_info *comp_info;
    /* comp_info[i] describes component that appears i'th in SOF */
  
    JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS];
  #if JPEG_LIB_VERSION >= 70
    int q_scale_factor[NUM_QUANT_TBLS];
  #endif
    /* ptrs to coefficient quantization tables, or NULL if not defined,
     * and corresponding scale factors (percentage, initialized 100).
     */
  
    JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
    JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
    /* ptrs to Huffman coding tables, or NULL if not defined */
  
    UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
    UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
    UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
  
    int num_scans;                /* # of entries in scan_info array */
    const jpeg_scan_info *scan_info; /* script for multi-scan file, or NULL */
    /* The default value of scan_info is NULL, which causes a single-scan
     * sequential JPEG file to be emitted.  To create a multi-scan file,
     * set num_scans and scan_info to point to an array of scan definitions.
     */
  
    boolean raw_data_in;          /* TRUE=caller supplies downsampled data */
    boolean arith_code;           /* TRUE=arithmetic coding, FALSE=Huffman */
    boolean optimize_coding;      /* TRUE=optimize entropy encoding parms */
    boolean CCIR601_sampling;     /* TRUE=first samples are cosited */
  #if JPEG_LIB_VERSION >= 70
    boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */
  #endif
    int smoothing_factor;         /* 1..100, or 0 for no input smoothing */
    J_DCT_METHOD dct_method;      /* DCT algorithm selector */
  
    /* The restart interval can be specified in absolute MCUs by setting
     * restart_interval, or in MCU rows by setting restart_in_rows
     * (in which case the correct restart_interval will be figured
     * for each scan).
     */
    unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
    int restart_in_rows;          /* if > 0, MCU rows per restart interval */
  
    /* Parameters controlling emission of special markers. */
  
    boolean write_JFIF_header;    /* should a JFIF marker be written? */
    UINT8 JFIF_major_version;     /* What to write for the JFIF version number */
    UINT8 JFIF_minor_version;
    /* These three values are not used by the JPEG code, merely copied */
    /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */
    /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */
    /* ratio is defined by X_density/Y_density even when density_unit=0. */
    UINT8 density_unit;           /* JFIF code for pixel size units */
    UINT16 X_density;             /* Horizontal pixel density */
    UINT16 Y_density;             /* Vertical pixel density */
    boolean write_Adobe_marker;   /* should an Adobe marker be written? */
  
    /* State variable: index of next scanline to be written to
     * jpeg_write_scanlines().  Application may use this to control its
     * processing loop, e.g., "while (next_scanline < image_height)".
     */
  
    JDIMENSION next_scanline;     /* 0 .. image_height-1  */
  
    /* Remaining fields are known throughout compressor, but generally
     * should not be touched by a surrounding application.
     */
  
    /*
     * These fields are computed during compression startup
     */
    boolean progressive_mode;     /* TRUE if scan script uses progressive mode */
    int max_h_samp_factor;        /* largest h_samp_factor */
    int max_v_samp_factor;        /* largest v_samp_factor */
  
  #if JPEG_LIB_VERSION >= 70
    int min_DCT_h_scaled_size;    /* smallest DCT_h_scaled_size of any component */
    int min_DCT_v_scaled_size;    /* smallest DCT_v_scaled_size of any component */
  #endif
  
    JDIMENSION total_iMCU_rows;   /* # of iMCU rows to be input to coef ctlr */
    /* The coefficient controller receives data in units of MCU rows as defined
     * for fully interleaved scans (whether the JPEG file is interleaved or not).
     * There are v_samp_factor * DCTSIZE sample rows of each component in an
     * "iMCU" (interleaved MCU) row.
     */
  
    /*
     * These fields are valid during any one scan.
     * They describe the components and MCUs actually appearing in the scan.
     */
    int comps_in_scan;            /* # of JPEG components in this scan */
    jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN];
    /* *cur_comp_info[i] describes component that appears i'th in SOS */
  
    JDIMENSION MCUs_per_row;      /* # of MCUs across the image */
    JDIMENSION MCU_rows_in_scan;  /* # of MCU rows in the image */
  
    int blocks_in_MCU;            /* # of DCT blocks per MCU */
    int MCU_membership[C_MAX_BLOCKS_IN_MCU];
    /* MCU_membership[i] is index in cur_comp_info of component owning */
    /* i'th block in an MCU */
  
    int Ss, Se, Ah, Al;           /* progressive JPEG parameters for scan */
  
  #if JPEG_LIB_VERSION >= 80
    int block_size;               /* the basic DCT block size: 1..16 */
    const int *natural_order;     /* natural-order position array */
    int lim_Se;                   /* min( Se, DCTSIZE2-1 ) */
  #endif
  
    /*
     * Links to compression subobjects (methods and private variables of modules)
     */
    struct jpeg_comp_master *master;
    struct jpeg_c_main_controller *main;
    struct jpeg_c_prep_controller *prep;
    struct jpeg_c_coef_controller *coef;
    struct jpeg_marker_writer *marker;
    struct jpeg_color_converter *cconvert;
    struct jpeg_downsampler *downsample;
    struct jpeg_forward_dct *fdct;
    struct jpeg_entropy_encoder *entropy;
    jpeg_scan_info *script_space; /* workspace for jpeg_simple_progression */
    int script_space_size;
  };
  
  
  /* Master record for a decompression instance */
  
  struct jpeg_decompress_struct {
    jpeg_common_fields;           /* Fields shared with jpeg_compress_struct */
  
    /* Source of compressed data */
    struct jpeg_source_mgr *src;
  
    /* Basic description of image --- filled in by jpeg_read_header(). */
    /* Application may inspect these values to decide how to process image. */
  
    JDIMENSION image_width;       /* nominal image width (from SOF marker) */
    JDIMENSION image_height;      /* nominal image height */
    int num_components;           /* # of color components in JPEG image */
    J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
  
    /* Decompression processing parameters --- these fields must be set before
     * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes
     * them to default values.
     */
  
    J_COLOR_SPACE out_color_space; /* colorspace for output */
  
    unsigned int scale_num, scale_denom; /* fraction by which to scale image */
  
    double output_gamma;          /* image gamma wanted in output */
  
    boolean buffered_image;       /* TRUE=multiple output passes */
    boolean raw_data_out;         /* TRUE=downsampled data wanted */
  
    J_DCT_METHOD dct_method;      /* IDCT algorithm selector */
    boolean do_fancy_upsampling;  /* TRUE=apply fancy upsampling */
    boolean do_block_smoothing;   /* TRUE=apply interblock smoothing */
  
    boolean quantize_colors;      /* TRUE=colormapped output wanted */
    /* the following are ignored if not quantize_colors: */
    J_DITHER_MODE dither_mode;    /* type of color dithering to use */
    boolean two_pass_quantize;    /* TRUE=use two-pass color quantization */
    int desired_number_of_colors; /* max # colors to use in created colormap */
    /* these are significant only in buffered-image mode: */
    boolean enable_1pass_quant;   /* enable future use of 1-pass quantizer */
    boolean enable_external_quant;/* enable future use of external colormap */
    boolean enable_2pass_quant;   /* enable future use of 2-pass quantizer */
  
    /* Description of actual output image that will be returned to application.
     * These fields are computed by jpeg_start_decompress().
     * You can also use jpeg_calc_output_dimensions() to determine these values
     * in advance of calling jpeg_start_decompress().
     */
  
    JDIMENSION output_width;      /* scaled image width */
    JDIMENSION output_height;     /* scaled image height */
    int out_color_components;     /* # of color components in out_color_space */
    int output_components;        /* # of color components returned */
    /* output_components is 1 (a colormap index) when quantizing colors;
     * otherwise it equals out_color_components.
     */
    int rec_outbuf_height;        /* min recommended height of scanline buffer */
    /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
     * high, space and time will be wasted due to unnecessary data copying.
     * Usually rec_outbuf_height will be 1 or 2, at most 4.
     */
  
    /* When quantizing colors, the output colormap is described by these fields.
     * The application can supply a colormap by setting colormap non-NULL before
     * calling jpeg_start_decompress; otherwise a colormap is created during
     * jpeg_start_decompress or jpeg_start_output.
     * The map has out_color_components rows and actual_number_of_colors columns.
     */
    int actual_number_of_colors;  /* number of entries in use */
    JSAMPARRAY colormap;          /* The color map as a 2-D pixel array */
  
    /* State variables: these variables indicate the progress of decompression.
     * The application may examine these but must not modify them.
     */
  
    /* Row index of next scanline to be read from jpeg_read_scanlines().
     * Application may use this to control its processing loop, e.g.,
     * "while (output_scanline < output_height)".
     */
    JDIMENSION output_scanline;   /* 0 .. output_height-1  */
  
    /* Current input scan number and number of iMCU rows completed in scan.
     * These indicate the progress of the decompressor input side.
     */
    int input_scan_number;        /* Number of SOS markers seen so far */
    JDIMENSION input_iMCU_row;    /* Number of iMCU rows completed */
  
    /* The "output scan number" is the notional scan being displayed by the
     * output side.  The decompressor will not allow output scan/row number
     * to get ahead of input scan/row, but it can fall arbitrarily far behind.
     */
    int output_scan_number;       /* Nominal scan number being displayed */
    JDIMENSION output_iMCU_row;   /* Number of iMCU rows read */
  
    /* Current progression status.  coef_bits[c][i] indicates the precision
     * with which component c's DCT coefficient i (in zigzag order) is known.
     * It is -1 when no data has yet been received, otherwise it is the point
     * transform (shift) value for the most recent scan of the coefficient
     * (thus, 0 at completion of the progression).
     * This pointer is NULL when reading a non-progressive file.
     */
    int (*coef_bits)[DCTSIZE2];   /* -1 or current Al value for each coef */
  
    /* Internal JPEG parameters --- the application usually need not look at
     * these fields.  Note that the decompressor output side may not use
     * any parameters that can change between scans.
     */
  
    /* Quantization and Huffman tables are carried forward across input
     * datastreams when processing abbreviated JPEG datastreams.
     */
  
    JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS];
    /* ptrs to coefficient quantization tables, or NULL if not defined */
  
    JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
    JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
    /* ptrs to Huffman coding tables, or NULL if not defined */
  
    /* These parameters are never carried across datastreams, since they
     * are given in SOF/SOS markers or defined to be reset by SOI.
     */
  
    int data_precision;           /* bits of precision in image data */
  
    jpeg_component_info *comp_info;
    /* comp_info[i] describes component that appears i'th in SOF */
  
  #if JPEG_LIB_VERSION >= 80
    boolean is_baseline;          /* TRUE if Baseline SOF0 encountered */
  #endif
    boolean progressive_mode;     /* TRUE if SOFn specifies progressive mode */
    boolean arith_code;           /* TRUE=arithmetic coding, FALSE=Huffman */
  
    UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
    UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
    UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
  
    unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
  
    /* These fields record data obtained from optional markers recognized by
     * the JPEG library.
     */
    boolean saw_JFIF_marker;      /* TRUE iff a JFIF APP0 marker was found */
    /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
    UINT8 JFIF_major_version;     /* JFIF version number */
    UINT8 JFIF_minor_version;
    UINT8 density_unit;           /* JFIF code for pixel size units */
    UINT16 X_density;             /* Horizontal pixel density */
    UINT16 Y_density;             /* Vertical pixel density */
    boolean saw_Adobe_marker;     /* TRUE iff an Adobe APP14 marker was found */
    UINT8 Adobe_transform;        /* Color transform code from Adobe marker */
  
    boolean CCIR601_sampling;     /* TRUE=first samples are cosited */
  
    /* Aside from the specific data retained from APPn markers known to the
     * library, the uninterpreted contents of any or all APPn and COM markers
     * can be saved in a list for examination by the application.
     */
    jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
  
    /* Remaining fields are known throughout decompressor, but generally
     * should not be touched by a surrounding application.
     */
  
    /*
     * These fields are computed during decompression startup
     */
    int max_h_samp_factor;        /* largest h_samp_factor */
    int max_v_samp_factor;        /* largest v_samp_factor */
  
  #if JPEG_LIB_VERSION >= 70
    int min_DCT_h_scaled_size;    /* smallest DCT_h_scaled_size of any component */
    int min_DCT_v_scaled_size;    /* smallest DCT_v_scaled_size of any component */
  #else
    int min_DCT_scaled_size;      /* smallest DCT_scaled_size of any component */
  #endif
  
    JDIMENSION total_iMCU_rows;   /* # of iMCU rows in image */
    /* The coefficient controller's input and output progress is measured in
     * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows
     * in fully interleaved JPEG scans, but are used whether the scan is
     * interleaved or not.  We define an iMCU row as v_samp_factor DCT block
     * rows of each component.  Therefore, the IDCT output contains
     * v_samp_factor*DCT_[v_]scaled_size sample rows of a component per iMCU row.
     */
  
    JSAMPLE *sample_range_limit;  /* table for fast range-limiting */
  
    /*
     * These fields are valid during any one scan.
     * They describe the components and MCUs actually appearing in the scan.
     * Note that the decompressor output side must not use these fields.
     */
    int comps_in_scan;            /* # of JPEG components in this scan */
    jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN];
    /* *cur_comp_info[i] describes component that appears i'th in SOS */
  
    JDIMENSION MCUs_per_row;      /* # of MCUs across the image */
    JDIMENSION MCU_rows_in_scan;  /* # of MCU rows in the image */
  
    int blocks_in_MCU;            /* # of DCT blocks per MCU */
    int MCU_membership[D_MAX_BLOCKS_IN_MCU];
    /* MCU_membership[i] is index in cur_comp_info of component owning */
    /* i'th block in an MCU */
  
    int Ss, Se, Ah, Al;           /* progressive JPEG parameters for scan */
  
  #if JPEG_LIB_VERSION >= 80
    /* These fields are derived from Se of first SOS marker.
     */
    int block_size;               /* the basic DCT block size: 1..16 */
    const int *natural_order; /* natural-order position array for entropy decode */
    int lim_Se;                   /* min( Se, DCTSIZE2-1 ) for entropy decode */
  #endif
  
    /* This field is shared between entropy decoder and marker parser.
     * It is either zero or the code of a JPEG marker that has been
     * read from the data source, but has not yet been processed.
     */
    int unread_marker;
  
    /*
     * Links to decompression subobjects (methods, private variables of modules)
     */
    struct jpeg_decomp_master *master;
    struct jpeg_d_main_controller *main;
    struct jpeg_d_coef_controller *coef;
    struct jpeg_d_post_controller *post;
    struct jpeg_input_controller *inputctl;
    struct jpeg_marker_reader *marker;
    struct jpeg_entropy_decoder *entropy;
    struct jpeg_inverse_dct *idct;
    struct jpeg_upsampler *upsample;
    struct jpeg_color_deconverter *cconvert;
    struct jpeg_color_quantizer *cquantize;
  
    boolean disable_merged_upsampling;  /* FALSE=Do not disable merged upsampling */
  };
  
  
  /* "Object" declarations for JPEG modules that may be supplied or called
   * directly by the surrounding application.
   * As with all objects in the JPEG library, these structs only define the
   * publicly visible methods and state variables of a module.  Additional
   * private fields may exist after the public ones.
   */
  
  
  /* Error handler object */
  
  struct jpeg_error_mgr {
    /* Error exit handler: does not return to caller */
    void (*error_exit) (j_common_ptr cinfo);
    /* Conditionally emit a trace or warning message */
    void (*emit_message) (j_common_ptr cinfo, int msg_level);
    /* Routine that actually outputs a trace or error message */
    void (*output_message) (j_common_ptr cinfo);
    /* Format a message string for the most recent JPEG error or message */
    void (*format_message) (j_common_ptr cinfo, char *buffer);
  #define JMSG_LENGTH_MAX  200    /* recommended size of format_message buffer */
    /* Reset error state variables at start of a new image */
    void (*reset_error_mgr) (j_common_ptr cinfo);
  
    /* The message ID code and any parameters are saved here.
     * A message can have one string parameter or up to 8 int parameters.
     */
    int msg_code;
  #define JMSG_STR_PARM_MAX  80
    union {
      int i[8];
      char s[JMSG_STR_PARM_MAX];
    } msg_parm;
  
    /* Standard state variables for error facility */
  
    int trace_level;              /* max msg_level that will be displayed */
  
    /* For recoverable corrupt-data errors, we emit a warning message,
     * but keep going unless emit_message chooses to abort.  emit_message
     * should count warnings in num_warnings.  The surrounding application
     * can check for bad data by seeing if num_warnings is nonzero at the
     * end of processing.
     */
    long num_warnings;            /* number of corrupt-data warnings */
  
    /* These fields point to the table(s) of error message strings.
     * An application can change the table pointer to switch to a different
     * message list (typically, to change the language in which errors are
     * reported).  Some applications may wish to add additional error codes
     * that will be handled by the JPEG library error mechanism; the second
     * table pointer is used for this purpose.
     *
     * First table includes all errors generated by JPEG library itself.
     * Error code 0 is reserved for a "no such error string" message.
     */
    const char * const *jpeg_message_table; /* Library errors */
    int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */
    /* Second table can be added by application (see cjpeg/djpeg for example).
     * It contains strings numbered first_addon_message..last_addon_message.
     */
    const char * const *addon_message_table; /* Non-library errors */
    int first_addon_message;      /* code for first string in addon table */
    int last_addon_message;       /* code for last string in addon table */
  };
  
  
  /* Progress monitor object */
  
  struct jpeg_progress_mgr {
    void (*progress_monitor) (j_common_ptr cinfo);
  
    long pass_counter;            /* work units completed in this pass */
    long pass_limit;              /* total number of work units in this pass */
    int completed_passes;         /* passes completed so far */
    int total_passes;             /* total number of passes expected */
  };
  
  
  /* Data destination object for compression */
  
  struct jpeg_destination_mgr {
    JOCTET *next_output_byte;     /* => next byte to write in buffer */
    size_t free_in_buffer;        /* # of byte spaces remaining in buffer */
  
    void (*init_destination) (j_compress_ptr cinfo);
    boolean (*empty_output_buffer) (j_compress_ptr cinfo);
    void (*term_destination) (j_compress_ptr cinfo);
  };
  
  
  /* Data source object for decompression */
  
  struct jpeg_source_mgr {
    const JOCTET *next_input_byte; /* => next byte to read from buffer */
    size_t bytes_in_buffer;       /* # of bytes remaining in buffer */
  
    void (*init_source) (j_decompress_ptr cinfo);
    boolean (*fill_input_buffer) (j_decompress_ptr cinfo);
    void (*skip_input_data) (j_decompress_ptr cinfo, long num_bytes);
    boolean (*resync_to_restart) (j_decompress_ptr cinfo, int desired);
    void (*term_source) (j_decompress_ptr cinfo);
  };
  
  
  /* Memory manager object.
   * Allocates "small" objects (a few K total), "large" objects (tens of K),
   * and "really big" objects (virtual arrays with backing store if needed).
   * The memory manager does not allow individual objects to be freed; rather,
   * each created object is assigned to a pool, and whole pools can be freed
   * at once.  This is faster and more convenient than remembering exactly what
   * to free, especially where malloc()/free() are not too speedy.
   * NB: alloc routines never return NULL.  They exit to error_exit if not
   * successful.
   */
  
  #define JPOOL_PERMANENT  0      /* lasts until master record is destroyed */
  #define JPOOL_IMAGE      1      /* lasts until done with image/datastream */
  #define JPOOL_NUMPOOLS   2
  
  typedef struct jvirt_sarray_control *jvirt_sarray_ptr;
  typedef struct jvirt_barray_control *jvirt_barray_ptr;
  
  
  struct jpeg_memory_mgr {
    /* Method pointers */
    void *(*alloc_small) (j_common_ptr cinfo, int pool_id, size_t sizeofobject);
    void *(*alloc_large) (j_common_ptr cinfo, int pool_id,
                          size_t sizeofobject);
    JSAMPARRAY (*alloc_sarray) (j_common_ptr cinfo, int pool_id,
                                JDIMENSION samplesperrow, JDIMENSION numrows);
    JBLOCKARRAY (*alloc_barray) (j_common_ptr cinfo, int pool_id,
                                 JDIMENSION blocksperrow, JDIMENSION numrows);
    jvirt_sarray_ptr (*request_virt_sarray) (j_common_ptr cinfo, int pool_id,
                                             boolean pre_zero,
                                             JDIMENSION samplesperrow,
                                             JDIMENSION numrows,
                                             JDIMENSION maxaccess);
    jvirt_barray_ptr (*request_virt_barray) (j_common_ptr cinfo, int pool_id,
                                             boolean pre_zero,
                                             JDIMENSION blocksperrow,
                                             JDIMENSION numrows,
                                             JDIMENSION maxaccess);
    void (*realize_virt_arrays) (j_common_ptr cinfo);
    JSAMPARRAY (*access_virt_sarray) (j_common_ptr cinfo, jvirt_sarray_ptr ptr,
                                      JDIMENSION start_row, JDIMENSION num_rows,
                                      boolean writable);
    JBLOCKARRAY (*access_virt_barray) (j_common_ptr cinfo, jvirt_barray_ptr ptr,
                                       JDIMENSION start_row, JDIMENSION num_rows,
                                       boolean writable);
    void (*free_pool) (j_common_ptr cinfo, int pool_id);
    void (*self_destruct) (j_common_ptr cinfo);
  
    /* Limit on memory allocation for this JPEG object.  (Note that this is
     * merely advisory, not a guaranteed maximum; it only affects the space
     * used for virtual-array buffers.)  May be changed by outer application
     * after creating the JPEG object.
     */
    long max_memory_to_use;
  
    /* Maximum allocation request accepted by alloc_large. */
    long max_alloc_chunk;
  };
  
  
  /* Routine signature for application-supplied marker processing methods.
   * Need not pass marker code since it is stored in cinfo->unread_marker.
   */
  typedef boolean (*jpeg_marker_parser_method) (j_decompress_ptr cinfo);
  
  
  /* Originally, this macro was used as a way of defining function prototypes
   * for both modern compilers as well as older compilers that did not support
   * prototype parameters.  libjpeg-turbo has never supported these older,
   * non-ANSI compilers, but the macro is still included because there is some
   * software out there that uses it.
   */
  
  #define JPP(arglist)    arglist
  
  
  /* Default error-management setup */
  EXTERN(struct jpeg_error_mgr *) jpeg_std_error(struct jpeg_error_mgr *err);
  
  /* Initialization of JPEG compression objects.
   * jpeg_create_compress() and jpeg_create_decompress() are the exported
   * names that applications should call.  These expand to calls on
   * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
   * passed for version mismatch checking.
   * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
   */
  #define jpeg_create_compress(cinfo) \
    jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
                        (size_t)sizeof(struct jpeg_compress_struct))
  #define jpeg_create_decompress(cinfo) \
    jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
                          (size_t)sizeof(struct jpeg_decompress_struct))
  EXTERN(void) jpeg_CreateCompress(j_compress_ptr cinfo, int version,
                                   size_t structsize);
  EXTERN(void) jpeg_CreateDecompress(j_decompress_ptr cinfo, int version,
                                     size_t structsize);
  /* Destruction of JPEG compression objects */
  EXTERN(void) jpeg_destroy_compress(j_compress_ptr cinfo);
  EXTERN(void) jpeg_destroy_decompress(j_decompress_ptr cinfo);
  
  /* Standard data source and destination managers: stdio streams. */
  /* Caller is responsible for opening the file before and closing after. */
  EXTERN(void) jpeg_stdio_dest(j_compress_ptr cinfo, FILE *outfile);
  EXTERN(void) jpeg_stdio_src(j_decompress_ptr cinfo, FILE *infile);
  
  #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
  /* Data source and destination managers: memory buffers. */
  EXTERN(void) jpeg_mem_dest(j_compress_ptr cinfo, unsigned char **outbuffer,
                             unsigned long *outsize);
  EXTERN(void) jpeg_mem_src(j_decompress_ptr cinfo,
                            const unsigned char *inbuffer, unsigned long insize);
  #endif
  
  /* Default parameter setup for compression */
  EXTERN(void) jpeg_set_defaults(j_compress_ptr cinfo);
  /* Compression parameter setup aids */
  EXTERN(void) jpeg_set_colorspace(j_compress_ptr cinfo,
                                   J_COLOR_SPACE colorspace);
  EXTERN(void) jpeg_default_colorspace(j_compress_ptr cinfo);
  EXTERN(void) jpeg_set_quality(j_compress_ptr cinfo, int quality,
                                boolean force_baseline);
  EXTERN(void) jpeg_set_linear_quality(j_compress_ptr cinfo, int scale_factor,
                                       boolean force_baseline);
  #if JPEG_LIB_VERSION >= 70
  EXTERN(void) jpeg_default_qtables(j_compress_ptr cinfo,
                                    boolean force_baseline);
  #endif
  EXTERN(void) jpeg_add_quant_table(j_compress_ptr cinfo, int which_tbl,
                                    const unsigned int *basic_table,
                                    int scale_factor, boolean force_baseline);
  EXTERN(int) jpeg_quality_scaling(int quality);
  EXTERN(void) jpeg_simple_progression(j_compress_ptr cinfo);
  EXTERN(void) jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress);
  EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table(j_common_ptr cinfo);
  EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table(j_common_ptr cinfo);
  
  /* Main entry points for compression */
  EXTERN(void) jpeg_start_compress(j_compress_ptr cinfo,
                                   boolean write_all_tables);
  EXTERN(JDIMENSION) jpeg_write_scanlines(j_compress_ptr cinfo,
                                          JSAMPARRAY scanlines,
                                          JDIMENSION num_lines);
  EXTERN(void) jpeg_finish_compress(j_compress_ptr cinfo);
  
  #if JPEG_LIB_VERSION >= 70
  /* Precalculate JPEG dimensions for current compression parameters. */
  EXTERN(void) jpeg_calc_jpeg_dimensions(j_compress_ptr cinfo);
  #endif
  
  /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
  EXTERN(JDIMENSION) jpeg_write_raw_data(j_compress_ptr cinfo, JSAMPIMAGE data,
                                         JDIMENSION num_lines);
  
  /* Write a special marker.  See libjpeg.txt concerning safe usage. */
  EXTERN(void) jpeg_write_marker(j_compress_ptr cinfo, int marker,
                                 const JOCTET *dataptr, unsigned int datalen);
  /* Same, but piecemeal. */
  EXTERN(void) jpeg_write_m_header(j_compress_ptr cinfo, int marker,
                                   unsigned int datalen);
  EXTERN(void) jpeg_write_m_byte(j_compress_ptr cinfo, int val);
  
  /* Alternate compression function: just write an abbreviated table file */
  EXTERN(void) jpeg_write_tables(j_compress_ptr cinfo);
  
  /* Write ICC profile.  See libjpeg.txt for usage information. */
  EXTERN(void) jpeg_write_icc_profile(j_compress_ptr cinfo,
                                      const JOCTET *icc_data_ptr,
                                      unsigned int icc_data_len);
  
  
  /* Decompression startup: read start of JPEG datastream to see what's there */
  EXTERN(int) jpeg_read_header(j_decompress_ptr cinfo, boolean require_image);
  /* Return value is one of: */
  #define JPEG_SUSPENDED           0 /* Suspended due to lack of input data */
  #define JPEG_HEADER_OK           1 /* Found valid image datastream */
  #define JPEG_HEADER_TABLES_ONLY  2 /* Found valid table-specs-only datastream */
  /* If you pass require_image = TRUE (normal case), you need not check for
   * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
   * JPEG_SUSPENDED is only possible if you use a data source module that can
   * give a suspension return (the stdio source module doesn't).
   */
  
  /* Main entry points for decompression */
  EXTERN(boolean) jpeg_start_decompress(j_decompress_ptr cinfo);
  EXTERN(JDIMENSION) jpeg_read_scanlines(j_decompress_ptr cinfo,
                                         JSAMPARRAY scanlines,
                                         JDIMENSION max_lines);
  EXTERN(JDIMENSION) jpeg_skip_scanlines(j_decompress_ptr cinfo,
                                         JDIMENSION num_lines);
  EXTERN(void) jpeg_crop_scanline(j_decompress_ptr cinfo, JDIMENSION *xoffset,
                                  JDIMENSION *width);
  EXTERN(boolean) jpeg_finish_decompress(j_decompress_ptr cinfo);
  
  /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
  EXTERN(JDIMENSION) jpeg_read_raw_data(j_decompress_ptr cinfo, JSAMPIMAGE data,
                                        JDIMENSION max_lines);
  
  /* Additional entry points for buffered-image mode. */
  EXTERN(boolean) jpeg_has_multiple_scans(j_decompress_ptr cinfo);
  EXTERN(boolean) jpeg_start_output(j_decompress_ptr cinfo, int scan_number);
  EXTERN(boolean) jpeg_finish_output(j_decompress_ptr cinfo);
  EXTERN(boolean) jpeg_input_complete(j_decompress_ptr cinfo);
  EXTERN(void) jpeg_new_colormap(j_decompress_ptr cinfo);
  EXTERN(int) jpeg_consume_input(j_decompress_ptr cinfo);
  /* Return value is one of: */
  /* #define JPEG_SUSPENDED       0    Suspended due to lack of input data */
  #define JPEG_REACHED_SOS        1 /* Reached start of new scan */
  #define JPEG_REACHED_EOI        2 /* Reached end of image */
  #define JPEG_ROW_COMPLETED      3 /* Completed one iMCU row */
  #define JPEG_SCAN_COMPLETED     4 /* Completed last iMCU row of a scan */
  
  /* Precalculate output dimensions for current decompression parameters. */
  #if JPEG_LIB_VERSION >= 80
  EXTERN(void) jpeg_core_output_dimensions(j_decompress_ptr cinfo);
  #endif
  EXTERN(void) jpeg_calc_output_dimensions(j_decompress_ptr cinfo);
  
  /* Control saving of COM and APPn markers into marker_list. */
  EXTERN(void) jpeg_save_markers(j_decompress_ptr cinfo, int marker_code,
                                 unsigned int length_limit);
  
  /* Install a special processing method for COM or APPn markers. */
  EXTERN(void) jpeg_set_marker_processor(j_decompress_ptr cinfo,
                                         int marker_code,
                                         jpeg_marker_parser_method routine);
  
  /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
  EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients(j_decompress_ptr cinfo);
  EXTERN(void) jpeg_write_coefficients(j_compress_ptr cinfo,
                                       jvirt_barray_ptr *coef_arrays);
  EXTERN(void) jpeg_copy_critical_parameters(j_decompress_ptr srcinfo,
                                             j_compress_ptr dstinfo);
  
  /* If you choose to abort compression or decompression before completing
   * jpeg_finish_(de)compress, then you need to clean up to release memory,
   * temporary files, etc.  You can just call jpeg_destroy_(de)compress
   * if you're done with the JPEG object, but if you want to clean it up and
   * reuse it, call this:
   */
  EXTERN(void) jpeg_abort_compress(j_compress_ptr cinfo);
  EXTERN(void) jpeg_abort_decompress(j_decompress_ptr cinfo);
  
  /* Generic versions of jpeg_abort and jpeg_destroy that work on either
   * flavor of JPEG object.  These may be more convenient in some places.
   */
  EXTERN(void) jpeg_abort(j_common_ptr cinfo);
  EXTERN(void) jpeg_destroy(j_common_ptr cinfo);
  
  /* Default restart-marker-resync procedure for use by data source modules */
  EXTERN(boolean) jpeg_resync_to_restart(j_decompress_ptr cinfo, int desired);
  
  /* Read ICC profile.  See libjpeg.txt for usage information. */
  EXTERN(boolean) jpeg_read_icc_profile(j_decompress_ptr cinfo,
                                        JOCTET **icc_data_ptr,
                                        unsigned int *icc_data_len);
  
  
  /* These marker codes are exported since applications and data source modules
   * are likely to want to use them.
   */
  
  #define JPEG_RST0       0xD0    /* RST0 marker code */
  #define JPEG_EOI        0xD9    /* EOI marker code */
  #define JPEG_APP0       0xE0    /* APP0 marker code */
  #define JPEG_COM        0xFE    /* COM marker code */
  
  
  /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
   * for structure definitions that are never filled in, keep it quiet by
   * supplying dummy definitions for the various substructures.
   */
  
  #ifdef INCOMPLETE_TYPES_BROKEN
  #ifndef JPEG_INTERNALS          /* will be defined in jpegint.h */
  struct jvirt_sarray_control { long dummy; };
  struct jvirt_barray_control { long dummy; };
  struct jpeg_comp_master { long dummy; };
  struct jpeg_c_main_controller { long dummy; };
  struct jpeg_c_prep_controller { long dummy; };
  struct jpeg_c_coef_controller { long dummy; };
  struct jpeg_marker_writer { long dummy; };
  struct jpeg_color_converter { long dummy; };
  struct jpeg_downsampler { long dummy; };
  struct jpeg_forward_dct { long dummy; };
  struct jpeg_entropy_encoder { long dummy; };
  struct jpeg_decomp_master { long dummy; };
  struct jpeg_d_main_controller { long dummy; };
  struct jpeg_d_coef_controller { long dummy; };
  struct jpeg_d_post_controller { long dummy; };
  struct jpeg_input_controller { long dummy; };
  struct jpeg_marker_reader { long dummy; };
  struct jpeg_entropy_decoder { long dummy; };
  struct jpeg_inverse_dct { long dummy; };
  struct jpeg_upsampler { long dummy; };
  struct jpeg_color_deconverter { long dummy; };
  struct jpeg_color_quantizer { long dummy; };
  #endif /* JPEG_INTERNALS */
  #endif /* INCOMPLETE_TYPES_BROKEN */
  
  
  /*
   * The JPEG library modules define JPEG_INTERNALS before including this file.
   * The internal structure declarations are read only when that is true.
   * Applications using the library should not include jpegint.h, but may wish
   * to include jerror.h.
   */
  
  #ifdef JPEG_INTERNALS
  #include "jpegint.h"            /* fetch private declarations */
  #include "jerror.h"             /* fetch error codes too */
  #endif
  
  #ifdef __cplusplus
  #ifndef DONT_USE_EXTERN_C
  }
  #endif
  #endif
  
  #endif /* JPEGLIB_H */
  