text: /*
   * jpeglib.h
   *
   * Copyright (C) 1991-1998, Thomas G. Lane.
   * This file is part of the Independent JPEG Group's software.
   * For conditions of distribution and use, see the accompanying README 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 */
  
  
  /* Version ID for the JPEG library.
   * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
   */
  
  #define JPEG_LIB_VERSION  62	/* Version 6b */
  
  
  /* 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).
   * On 80x86 machines, the image arrays are too big for near pointers,
   * but the pointer arrays can fit in near memory.
   */
  
  typedef JSAMPLE FAR *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 FAR *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 FAR *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 of 1,2,4,8 are likely to be supported.  Note that different
     * components may receive different IDCT scalings.
     */
    int DCT_scaled_size;
    /* 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_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_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 FAR * 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 FAR * data;		/* the data contained in the marker */
    /* the marker length word is not counted in data_length or original_length */
  };
  
  /* Known color spaces. */
  
  typedef enum {
  	JCS_UNKNOWN,		/* error/unspecified */
  	JCS_GRAYSCALE,		/* monochrome */
  	JCS_RGB,		/* red/green/blue */
  	JCS_YCbCr,		/* Y/Cb/Cr (also known as YUV) */
  	JCS_CMYK,		/* C/M/Y/K */
  	JCS_YCCK		/* Y/Cb/Cr/K */
  } 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.
     */
  
    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];
    /* 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 */
    
    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 */
    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 */
  
    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 */
  
    /*
     * 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 */
  
    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 */
  
    int min_DCT_scaled_size;	/* smallest DCT_scaled_size of any component */
  
    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_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 */
  
    /* 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;
  };
  
  
  /* "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 */
    JMETHOD(void, error_exit, (j_common_ptr cinfo));
    /* Conditionally emit a trace or warning message */
    JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
    /* Routine that actually outputs a trace or error message */
    JMETHOD(void, output_message, (j_common_ptr cinfo));
    /* Format a message string for the most recent JPEG error or message */
    JMETHOD(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 */
    JMETHOD(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 {
    JMETHOD(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 */
  
    JMETHOD(void, init_destination, (j_compress_ptr cinfo));
    JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
    JMETHOD(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 */
  
    JMETHOD(void, init_source, (j_decompress_ptr cinfo));
    JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
    JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
    JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
    JMETHOD(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 */
    JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
  				size_t sizeofobject));
    JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
  				     size_t sizeofobject));
    JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
  				     JDIMENSION samplesperrow,
  				     JDIMENSION numrows));
    JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
  				      JDIMENSION blocksperrow,
  				      JDIMENSION numrows));
    JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
  						  int pool_id,
  						  boolean pre_zero,
  						  JDIMENSION samplesperrow,
  						  JDIMENSION numrows,
  						  JDIMENSION maxaccess));
    JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
  						  int pool_id,
  						  boolean pre_zero,
  						  JDIMENSION blocksperrow,
  						  JDIMENSION numrows,
  						  JDIMENSION maxaccess));
    JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
    JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
  					   jvirt_sarray_ptr ptr,
  					   JDIMENSION start_row,
  					   JDIMENSION num_rows,
  					   boolean writable));
    JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
  					    jvirt_barray_ptr ptr,
  					    JDIMENSION start_row,
  					    JDIMENSION num_rows,
  					    boolean writable));
    JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
    JMETHOD(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 JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
  
  
  /* Declarations for routines called by application.
   * The JPP macro hides prototype parameters from compilers that can't cope.
   * Note JPP requires double parentheses.
   */
  
  #ifdef HAVE_PROTOTYPES
  #define JPP(arglist)	arglist
  #else
  #define JPP(arglist)	()
  #endif
  
  
  /* Short forms of external names for systems with brain-damaged linkers.
   * We shorten external names to be unique in the first six letters, which
   * is good enough for all known systems.
   * (If your compiler itself needs names to be unique in less than 15 
   * characters, you are out of luck.  Get a better compiler.)
   */
  
  #ifdef NEED_SHORT_EXTERNAL_NAMES
  #define jpeg_std_error		jStdError
  #define jpeg_CreateCompress	jCreaCompress
  #define jpeg_CreateDecompress	jCreaDecompress
  #define jpeg_destroy_compress	jDestCompress
  #define jpeg_destroy_decompress	jDestDecompress
  #define jpeg_stdio_dest		jStdDest
  #define jpeg_stdio_src		jStdSrc
  #define jpeg_set_defaults	jSetDefaults
  #define jpeg_set_colorspace	jSetColorspace
  #define jpeg_default_colorspace	jDefColorspace
  #define jpeg_set_quality	jSetQuality
  #define jpeg_set_linear_quality	jSetLQuality
  #define jpeg_add_quant_table	jAddQuantTable
  #define jpeg_quality_scaling	jQualityScaling
  #define jpeg_simple_progression	jSimProgress
  #define jpeg_suppress_tables	jSuppressTables
  #define jpeg_alloc_quant_table	jAlcQTable
  #define jpeg_alloc_huff_table	jAlcHTable
  #define jpeg_start_compress	jStrtCompress
  #define jpeg_write_scanlines	jWrtScanlines
  #define jpeg_finish_compress	jFinCompress
  #define jpeg_write_raw_data	jWrtRawData
  #define jpeg_write_marker	jWrtMarker
  #define jpeg_write_m_header	jWrtMHeader
  #define jpeg_write_m_byte	jWrtMByte
  #define jpeg_write_tables	jWrtTables
  #define jpeg_read_header	jReadHeader
  #define jpeg_start_decompress	jStrtDecompress
  #define jpeg_read_scanlines	jReadScanlines
  #define jpeg_finish_decompress	jFinDecompress
  #define jpeg_read_raw_data	jReadRawData
  #define jpeg_has_multiple_scans	jHasMultScn
  #define jpeg_start_output	jStrtOutput
  #define jpeg_finish_output	jFinOutput
  #define jpeg_input_complete	jInComplete
  #define jpeg_new_colormap	jNewCMap
  #define jpeg_consume_input	jConsumeInput
  #define jpeg_calc_output_dimensions	jCalcDimensions
  #define jpeg_save_markers	jSaveMarkers
  #define jpeg_set_marker_processor	jSetMarker
  #define jpeg_read_coefficients	jReadCoefs
  #define jpeg_write_coefficients	jWrtCoefs
  #define jpeg_copy_critical_parameters	jCopyCrit
  #define jpeg_abort_compress	jAbrtCompress
  #define jpeg_abort_decompress	jAbrtDecompress
  #define jpeg_abort		jAbort
  #define jpeg_destroy		jDestroy
  #define jpeg_resync_to_restart	jResyncRestart
  #endif /* NEED_SHORT_EXTERNAL_NAMES */
  
  
  /* Default error-management setup */
  EXTERN(struct jpeg_error_mgr *) jpeg_std_error
  	JPP((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 JPP((j_compress_ptr cinfo,
  				      int version, size_t structsize));
  EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
  					int version, size_t structsize));
  /* Destruction of JPEG compression objects */
  EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
  EXTERN(void) jpeg_destroy_decompress JPP((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 JPP((j_compress_ptr cinfo, FILE * outfile));
  EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
  
  /* Default parameter setup for compression */
  EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
  /* Compression parameter setup aids */
  EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
  				      J_COLOR_SPACE colorspace));
  EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
  EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
  				   boolean force_baseline));
  EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
  					  int scale_factor,
  					  boolean force_baseline));
  EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
  				       const unsigned int *basic_table,
  				       int scale_factor,
  				       boolean force_baseline));
  EXTERN(int) jpeg_quality_scaling JPP((int quality));
  EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
  EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
  				       boolean suppress));
  EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
  EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
  
  /* Main entry points for compression */
  EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
  				      boolean write_all_tables));
  EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
  					     JSAMPARRAY scanlines,
  					     JDIMENSION num_lines));
  EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
  
  /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
  EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
  					    JSAMPIMAGE data,
  					    JDIMENSION num_lines));
  
  /* Write a special marker.  See libjpeg.doc concerning safe usage. */
  EXTERN(void) jpeg_write_marker
  	JPP((j_compress_ptr cinfo, int marker,
  	     const JOCTET * dataptr, unsigned int datalen));
  /* Same, but piecemeal. */
  EXTERN(void) jpeg_write_m_header
  	JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
  EXTERN(void) jpeg_write_m_byte
  	JPP((j_compress_ptr cinfo, int val));
  
  /* Alternate compression function: just write an abbreviated table file */
  EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
  
  /* Decompression startup: read start of JPEG datastream to see what's there */
  EXTERN(int) jpeg_read_header JPP((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 JPP((j_decompress_ptr cinfo));
  EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
  					    JSAMPARRAY scanlines,
  					    JDIMENSION max_lines));
  EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
  
  /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
  EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
  					   JSAMPIMAGE data,
  					   JDIMENSION max_lines));
  
  /* Additional entry points for buffered-image mode. */
  EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
  EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
  				       int scan_number));
  EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
  EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
  EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
  EXTERN(int) jpeg_consume_input JPP((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. */
  EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
  
  /* Control saving of COM and APPn markers into marker_list. */
  EXTERN(void) jpeg_save_markers
  	JPP((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
  	JPP((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 JPP((j_decompress_ptr cinfo));
  EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
  					  jvirt_barray_ptr * coef_arrays));
  EXTERN(void) jpeg_copy_critical_parameters JPP((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 JPP((j_compress_ptr cinfo));
  EXTERN(void) jpeg_abort_decompress JPP((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 JPP((j_common_ptr cinfo));
  EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
  
  /* Default restart-marker-resync procedure for use by data source modules */
  EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
  					    int desired));
  
  
  /* 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
  
  #endif /* JPEGLIB_H */
  