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00001 /*
+00002  * jpeglib.h
+00003  *
+00004  * Copyright (C) 1991-1998, Thomas G. Lane.
+00005  * This file is part of the Independent JPEG Group's software.
+00006  * For conditions of distribution and use, see the accompanying README file.
+00007  *
+00008  * This file defines the application interface for the JPEG library.
+00009  * Most applications using the library need only include this file,
+00010  * and perhaps jerror.h if they want to know the exact error codes.
+00011  */
+00012 
+00013 #ifndef JPEGLIB_H
+00014 #define JPEGLIB_H
+00015 
+00016 /*
+00017  * First we include the configuration files that record how this
+00018  * installation of the JPEG library is set up.  jconfig.h can be
+00019  * generated automatically for many systems.  jmorecfg.h contains
+00020  * manual configuration options that most people need not worry about.
+00021  */
+00022 
+00023 #ifndef JCONFIG_INCLUDED        /* in case jinclude.h already did */
+00024 #include "jconfig.h"            /* widely used configuration options */
+00025 #endif
+00026 #include "jmorecfg.h"           /* seldom changed options */
+00027 
+00028 
+00029 /* Version ID for the JPEG library.
+00030  * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
+00031  */
+00032 
+00033 #define JPEG_LIB_VERSION  62    /* Version 6b */
+00034 
+00035 
+00036 /* Various constants determining the sizes of things.
+00037  * All of these are specified by the JPEG standard, so don't change them
+00038  * if you want to be compatible.
+00039  */
+00040 
+00041 #define DCTSIZE             8   /* The basic DCT block is 8x8 samples */
+00042 #define DCTSIZE2            64  /* DCTSIZE squared; # of elements in a block */
+00043 #define NUM_QUANT_TBLS      4   /* Quantization tables are numbered 0..3 */
+00044 #define NUM_HUFF_TBLS       4   /* Huffman tables are numbered 0..3 */
+00045 #define NUM_ARITH_TBLS      16  /* Arith-coding tables are numbered 0..15 */
+00046 #define MAX_COMPS_IN_SCAN   4   /* JPEG limit on # of components in one scan */
+00047 #define MAX_SAMP_FACTOR     4   /* JPEG limit on sampling factors */
+00048 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
+00049  * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
+00050  * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
+00051  * to handle it.  We even let you do this from the jconfig.h file.  However,
+00052  * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
+00053  * sometimes emits noncompliant files doesn't mean you should too.
+00054  */
+00055 #define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
+00056 #ifndef D_MAX_BLOCKS_IN_MCU
+00057 #define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
+00058 #endif
+00059 
+00060 
+00061 /* Data structures for images (arrays of samples and of DCT coefficients).
+00062  * On 80x86 machines, the image arrays are too big for near pointers,
+00063  * but the pointer arrays can fit in near memory.
+00064  */
+00065 
+00066 typedef JSAMPLE FAR *JSAMPROW;  /* ptr to one image row of pixel samples. */
+00067 typedef JSAMPROW *JSAMPARRAY;   /* ptr to some rows (a 2-D sample array) */
+00068 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
+00069 
+00070 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
+00071 typedef JBLOCK FAR *JBLOCKROW;  /* pointer to one row of coefficient blocks */
+00072 typedef JBLOCKROW *JBLOCKARRAY;         /* a 2-D array of coefficient blocks */
+00073 typedef JBLOCKARRAY *JBLOCKIMAGE;       /* a 3-D array of coefficient blocks */
+00074 
+00075 typedef JCOEF FAR *JCOEFPTR;    /* useful in a couple of places */
+00076 
+00077 
+00078 /* Types for JPEG compression parameters and working tables. */
+00079 
+00080 
+00081 /* DCT coefficient quantization tables. */
+00082 
+00083 typedef struct {
+00084   /* This array gives the coefficient quantizers in natural array order
+00085    * (not the zigzag order in which they are stored in a JPEG DQT marker).
+00086    * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
+00087    */
+00088   UINT16 quantval[DCTSIZE2];    /* quantization step for each coefficient */
+00089   /* This field is used only during compression.  It's initialized FALSE when
+00090    * the table is created, and set TRUE when it's been output to the file.
+00091    * You could suppress output of a table by setting this to TRUE.
+00092    * (See jpeg_suppress_tables for an example.)
+00093    */
+00094   boolean sent_table;           /* TRUE when table has been output */
+00095 } JQUANT_TBL;
+00096 
+00097 
+00098 /* Huffman coding tables. */
+00099 
+00100 typedef struct {
+00101   /* These two fields directly represent the contents of a JPEG DHT marker */
+00102   UINT8 bits[17];               /* bits[k] = # of symbols with codes of */
+00103                                 /* length k bits; bits[0] is unused */
+00104   UINT8 huffval[256];           /* The symbols, in order of incr code length */
+00105   /* This field is used only during compression.  It's initialized FALSE when
+00106    * the table is created, and set TRUE when it's been output to the file.
+00107    * You could suppress output of a table by setting this to TRUE.
+00108    * (See jpeg_suppress_tables for an example.)
+00109    */
+00110   boolean sent_table;           /* TRUE when table has been output */
+00111 } JHUFF_TBL;
+00112 
+00113 
+00114 /* Basic info about one component (color channel). */
+00115 
+00116 typedef struct {
+00117   /* These values are fixed over the whole image. */
+00118   /* For compression, they must be supplied by parameter setup; */
+00119   /* for decompression, they are read from the SOF marker. */
+00120   int component_id;             /* identifier for this component (0..255) */
+00121   int component_index;          /* its index in SOF or cinfo->comp_info[] */
+00122   int h_samp_factor;            /* horizontal sampling factor (1..4) */
+00123   int v_samp_factor;            /* vertical sampling factor (1..4) */
+00124   int quant_tbl_no;             /* quantization table selector (0..3) */
+00125   /* These values may vary between scans. */
+00126   /* For compression, they must be supplied by parameter setup; */
+00127   /* for decompression, they are read from the SOS marker. */
+00128   /* The decompressor output side may not use these variables. */
+00129   int dc_tbl_no;                /* DC entropy table selector (0..3) */
+00130   int ac_tbl_no;                /* AC entropy table selector (0..3) */
+00131   
+00132   /* Remaining fields should be treated as private by applications. */
+00133   
+00134   /* These values are computed during compression or decompression startup: */
+00135   /* Component's size in DCT blocks.
+00136    * Any dummy blocks added to complete an MCU are not counted; therefore
+00137    * these values do not depend on whether a scan is interleaved or not.
+00138    */
+00139   JDIMENSION width_in_blocks;
+00140   JDIMENSION height_in_blocks;
+00141   /* Size of a DCT block in samples.  Always DCTSIZE for compression.
+00142    * For decompression this is the size of the output from one DCT block,
+00143    * reflecting any scaling we choose to apply during the IDCT step.
+00144    * Values of 1,2,4,8 are likely to be supported.  Note that different
+00145    * components may receive different IDCT scalings.
+00146    */
+00147   int DCT_scaled_size;
+00148   /* The downsampled dimensions are the component's actual, unpadded number
+00149    * of samples at the main buffer (preprocessing/compression interface), thus
+00150    * downsampled_width = ceil(image_width * Hi/Hmax)
+00151    * and similarly for height.  For decompression, IDCT scaling is included, so
+00152    * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
+00153    */
+00154   JDIMENSION downsampled_width;  /* actual width in samples */
+00155   JDIMENSION downsampled_height; /* actual height in samples */
+00156   /* This flag is used only for decompression.  In cases where some of the
+00157    * components will be ignored (eg grayscale output from YCbCr image),
+00158    * we can skip most computations for the unused components.
+00159    */
+00160   boolean component_needed;     /* do we need the value of this component? */
+00161 
+00162   /* These values are computed before starting a scan of the component. */
+00163   /* The decompressor output side may not use these variables. */
+00164   int MCU_width;                /* number of blocks per MCU, horizontally */
+00165   int MCU_height;               /* number of blocks per MCU, vertically */
+00166   int MCU_blocks;               /* MCU_width * MCU_height */
+00167   int MCU_sample_width;         /* MCU width in samples, MCU_width*DCT_scaled_size */
+00168   int last_col_width;           /* # of non-dummy blocks across in last MCU */
+00169   int last_row_height;          /* # of non-dummy blocks down in last MCU */
+00170 
+00171   /* Saved quantization table for component; NULL if none yet saved.
+00172    * See jdinput.c comments about the need for this information.
+00173    * This field is currently used only for decompression.
+00174    */
+00175   JQUANT_TBL * quant_table;
+00176 
+00177   /* Private per-component storage for DCT or IDCT subsystem. */
+00178   void * dct_table;
+00179 } jpeg_component_info;
+00180 
+00181 
+00182 /* The script for encoding a multiple-scan file is an array of these: */
+00183 
+00184 typedef struct {
+00185   int comps_in_scan;            /* number of components encoded in this scan */
+00186   int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
+00187   int Ss, Se;                   /* progressive JPEG spectral selection parms */
+00188   int Ah, Al;                   /* progressive JPEG successive approx. parms */
+00189 } jpeg_scan_info;
+00190 
+00191 /* The decompressor can save APPn and COM markers in a list of these: */
+00192 
+00193 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
+00194 
+00195 struct jpeg_marker_struct {
+00196   jpeg_saved_marker_ptr next;   /* next in list, or NULL */
+00197   UINT8 marker;                 /* marker code: JPEG_COM, or JPEG_APP0+n */
+00198   unsigned int original_length; /* # bytes of data in the file */
+00199   unsigned int data_length;     /* # bytes of data saved at data[] */
+00200   JOCTET FAR * data;            /* the data contained in the marker */
+00201   /* the marker length word is not counted in data_length or original_length */
+00202 };
+00203 
+00204 /* Known color spaces. */
+00205 
+00206 typedef enum {
+00207         JCS_UNKNOWN,            /* error/unspecified */
+00208         JCS_GRAYSCALE,          /* monochrome */
+00209         JCS_RGB,                /* red/green/blue */
+00210         JCS_YCbCr,              /* Y/Cb/Cr (also known as YUV) */
+00211         JCS_CMYK,               /* C/M/Y/K */
+00212         JCS_YCCK                /* Y/Cb/Cr/K */
+00213 } J_COLOR_SPACE;
+00214 
+00215 /* DCT/IDCT algorithm options. */
+00216 
+00217 typedef enum {
+00218         JDCT_ISLOW,             /* slow but accurate integer algorithm */
+00219         JDCT_IFAST,             /* faster, less accurate integer method */
+00220         JDCT_FLOAT              /* floating-point: accurate, fast on fast HW */
+00221 } J_DCT_METHOD;
+00222 
+00223 #ifndef JDCT_DEFAULT            /* may be overridden in jconfig.h */
+00224 #define JDCT_DEFAULT  JDCT_ISLOW
+00225 #endif
+00226 #ifndef JDCT_FASTEST            /* may be overridden in jconfig.h */
+00227 #define JDCT_FASTEST  JDCT_IFAST
+00228 #endif
+00229 
+00230 /* Dithering options for decompression. */
+00231 
+00232 typedef enum {
+00233         JDITHER_NONE,           /* no dithering */
+00234         JDITHER_ORDERED,        /* simple ordered dither */
+00235         JDITHER_FS              /* Floyd-Steinberg error diffusion dither */
+00236 } J_DITHER_MODE;
+00237 
+00238 
+00239 /* Common fields between JPEG compression and decompression master structs. */
+00240 
+00241 #define jpeg_common_fields \
+00242   struct jpeg_error_mgr * err;  /* Error handler module */\
+00243   struct jpeg_memory_mgr * mem; /* Memory manager module */\
+00244   struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
+00245   void * client_data;           /* Available for use by application */\
+00246   boolean is_decompressor;      /* So common code can tell which is which */\
+00247   int global_state              /* For checking call sequence validity */
+00248 
+00249 /* Routines that are to be used by both halves of the library are declared
+00250  * to receive a pointer to this structure.  There are no actual instances of
+00251  * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
+00252  */
+00253 struct jpeg_common_struct {
+00254   jpeg_common_fields;           /* Fields common to both master struct types */
+00255   /* Additional fields follow in an actual jpeg_compress_struct or
+00256    * jpeg_decompress_struct.  All three structs must agree on these
+00257    * initial fields!  (This would be a lot cleaner in C++.)
+00258    */
+00259 };
+00260 
+00261 typedef struct jpeg_common_struct * j_common_ptr;
+00262 typedef struct jpeg_compress_struct * j_compress_ptr;
+00263 typedef struct jpeg_decompress_struct * j_decompress_ptr;
+00264 
+00265 
+00266 /* Master record for a compression instance */
+00267 
+00268 struct jpeg_compress_struct {
+00269   jpeg_common_fields;           /* Fields shared with jpeg_decompress_struct */
+00270 
+00271   /* Destination for compressed data */
+00272   struct jpeg_destination_mgr * dest;
+00273 
+00274   /* Description of source image --- these fields must be filled in by
+00275    * outer application before starting compression.  in_color_space must
+00276    * be correct before you can even call jpeg_set_defaults().
+00277    */
+00278 
+00279   JDIMENSION image_width;       /* input image width */
+00280   JDIMENSION image_height;      /* input image height */
+00281   int input_components;         /* # of color components in input image */
+00282   J_COLOR_SPACE in_color_space; /* colorspace of input image */
+00283 
+00284   double input_gamma;           /* image gamma of input image */
+00285 
+00286   /* Compression parameters --- these fields must be set before calling
+00287    * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to
+00288    * initialize everything to reasonable defaults, then changing anything
+00289    * the application specifically wants to change.  That way you won't get
+00290    * burnt when new parameters are added.  Also note that there are several
+00291    * helper routines to simplify changing parameters.
+00292    */
+00293 
+00294   int data_precision;           /* bits of precision in image data */
+00295 
+00296   int num_components;           /* # of color components in JPEG image */
+00297   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
+00298 
+00299   jpeg_component_info * comp_info;
+00300   /* comp_info[i] describes component that appears i'th in SOF */
+00301   
+00302   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
+00303   /* ptrs to coefficient quantization tables, or NULL if not defined */
+00304   
+00305   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
+00306   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
+00307   /* ptrs to Huffman coding tables, or NULL if not defined */
+00308   
+00309   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
+00310   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
+00311   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
+00312 
+00313   int num_scans;                /* # of entries in scan_info array */
+00314   const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
+00315   /* The default value of scan_info is NULL, which causes a single-scan
+00316    * sequential JPEG file to be emitted.  To create a multi-scan file,
+00317    * set num_scans and scan_info to point to an array of scan definitions.
+00318    */
+00319 
+00320   boolean raw_data_in;          /* TRUE=caller supplies downsampled data */
+00321   boolean arith_code;           /* TRUE=arithmetic coding, FALSE=Huffman */
+00322   boolean optimize_coding;      /* TRUE=optimize entropy encoding parms */
+00323   boolean CCIR601_sampling;     /* TRUE=first samples are cosited */
+00324   int smoothing_factor;         /* 1..100, or 0 for no input smoothing */
+00325   J_DCT_METHOD dct_method;      /* DCT algorithm selector */
+00326 
+00327   /* The restart interval can be specified in absolute MCUs by setting
+00328    * restart_interval, or in MCU rows by setting restart_in_rows
+00329    * (in which case the correct restart_interval will be figured
+00330    * for each scan).
+00331    */
+00332   unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
+00333   int restart_in_rows;          /* if > 0, MCU rows per restart interval */
+00334 
+00335   /* Parameters controlling emission of special markers. */
+00336 
+00337   boolean write_JFIF_header;    /* should a JFIF marker be written? */
+00338   UINT8 JFIF_major_version;     /* What to write for the JFIF version number */
+00339   UINT8 JFIF_minor_version;
+00340   /* These three values are not used by the JPEG code, merely copied */
+00341   /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */
+00342   /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */
+00343   /* ratio is defined by X_density/Y_density even when density_unit=0. */
+00344   UINT8 density_unit;           /* JFIF code for pixel size units */
+00345   UINT16 X_density;             /* Horizontal pixel density */
+00346   UINT16 Y_density;             /* Vertical pixel density */
+00347   boolean write_Adobe_marker;   /* should an Adobe marker be written? */
+00348   
+00349   /* State variable: index of next scanline to be written to
+00350    * jpeg_write_scanlines().  Application may use this to control its
+00351    * processing loop, e.g., "while (next_scanline < image_height)".
+00352    */
+00353 
+00354   JDIMENSION next_scanline;     /* 0 .. image_height-1  */
+00355 
+00356   /* Remaining fields are known throughout compressor, but generally
+00357    * should not be touched by a surrounding application.
+00358    */
+00359 
+00360   /*
+00361    * These fields are computed during compression startup
+00362    */
+00363   boolean progressive_mode;     /* TRUE if scan script uses progressive mode */
+00364   int max_h_samp_factor;        /* largest h_samp_factor */
+00365   int max_v_samp_factor;        /* largest v_samp_factor */
+00366 
+00367   JDIMENSION total_iMCU_rows;   /* # of iMCU rows to be input to coef ctlr */
+00368   /* The coefficient controller receives data in units of MCU rows as defined
+00369    * for fully interleaved scans (whether the JPEG file is interleaved or not).
+00370    * There are v_samp_factor * DCTSIZE sample rows of each component in an
+00371    * "iMCU" (interleaved MCU) row.
+00372    */
+00373   
+00374   /*
+00375    * These fields are valid during any one scan.
+00376    * They describe the components and MCUs actually appearing in the scan.
+00377    */
+00378   int comps_in_scan;            /* # of JPEG components in this scan */
+00379   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
+00380   /* *cur_comp_info[i] describes component that appears i'th in SOS */
+00381   
+00382   JDIMENSION MCUs_per_row;      /* # of MCUs across the image */
+00383   JDIMENSION MCU_rows_in_scan;  /* # of MCU rows in the image */
+00384   
+00385   int blocks_in_MCU;            /* # of DCT blocks per MCU */
+00386   int MCU_membership[C_MAX_BLOCKS_IN_MCU];
+00387   /* MCU_membership[i] is index in cur_comp_info of component owning */
+00388   /* i'th block in an MCU */
+00389 
+00390   int Ss, Se, Ah, Al;           /* progressive JPEG parameters for scan */
+00391 
+00392   /*
+00393    * Links to compression subobjects (methods and private variables of modules)
+00394    */
+00395   struct jpeg_comp_master * master;
+00396   struct jpeg_c_main_controller * main;
+00397   struct jpeg_c_prep_controller * prep;
+00398   struct jpeg_c_coef_controller * coef;
+00399   struct jpeg_marker_writer * marker;
+00400   struct jpeg_color_converter * cconvert;
+00401   struct jpeg_downsampler * downsample;
+00402   struct jpeg_forward_dct * fdct;
+00403   struct jpeg_entropy_encoder * entropy;
+00404   jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
+00405   int script_space_size;
+00406 };
+00407 
+00408 
+00409 /* Master record for a decompression instance */
+00410 
+00411 struct jpeg_decompress_struct {
+00412   jpeg_common_fields;           /* Fields shared with jpeg_compress_struct */
+00413 
+00414   /* Source of compressed data */
+00415   struct jpeg_source_mgr * src;
+00416 
+00417   /* Basic description of image --- filled in by jpeg_read_header(). */
+00418   /* Application may inspect these values to decide how to process image. */
+00419 
+00420   JDIMENSION image_width;       /* nominal image width (from SOF marker) */
+00421   JDIMENSION image_height;      /* nominal image height */
+00422   int num_components;           /* # of color components in JPEG image */
+00423   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
+00424 
+00425   /* Decompression processing parameters --- these fields must be set before
+00426    * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes
+00427    * them to default values.
+00428    */
+00429 
+00430   J_COLOR_SPACE out_color_space; /* colorspace for output */
+00431 
+00432   unsigned int scale_num, scale_denom; /* fraction by which to scale image */
+00433 
+00434   double output_gamma;          /* image gamma wanted in output */
+00435 
+00436   boolean buffered_image;       /* TRUE=multiple output passes */
+00437   boolean raw_data_out;         /* TRUE=downsampled data wanted */
+00438 
+00439   J_DCT_METHOD dct_method;      /* IDCT algorithm selector */
+00440   boolean do_fancy_upsampling;  /* TRUE=apply fancy upsampling */
+00441   boolean do_block_smoothing;   /* TRUE=apply interblock smoothing */
+00442 
+00443   boolean quantize_colors;      /* TRUE=colormapped output wanted */
+00444   /* the following are ignored if not quantize_colors: */
+00445   J_DITHER_MODE dither_mode;    /* type of color dithering to use */
+00446   boolean two_pass_quantize;    /* TRUE=use two-pass color quantization */
+00447   int desired_number_of_colors; /* max # colors to use in created colormap */
+00448   /* these are significant only in buffered-image mode: */
+00449   boolean enable_1pass_quant;   /* enable future use of 1-pass quantizer */
+00450   boolean enable_external_quant;/* enable future use of external colormap */
+00451   boolean enable_2pass_quant;   /* enable future use of 2-pass quantizer */
+00452 
+00453   /* Description of actual output image that will be returned to application.
+00454    * These fields are computed by jpeg_start_decompress().
+00455    * You can also use jpeg_calc_output_dimensions() to determine these values
+00456    * in advance of calling jpeg_start_decompress().
+00457    */
+00458 
+00459   JDIMENSION output_width;      /* scaled image width */
+00460   JDIMENSION output_height;     /* scaled image height */
+00461   int out_color_components;     /* # of color components in out_color_space */
+00462   int output_components;        /* # of color components returned */
+00463   /* output_components is 1 (a colormap index) when quantizing colors;
+00464    * otherwise it equals out_color_components.
+00465    */
+00466   int rec_outbuf_height;        /* min recommended height of scanline buffer */
+00467   /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
+00468    * high, space and time will be wasted due to unnecessary data copying.
+00469    * Usually rec_outbuf_height will be 1 or 2, at most 4.
+00470    */
+00471 
+00472   /* When quantizing colors, the output colormap is described by these fields.
+00473    * The application can supply a colormap by setting colormap non-NULL before
+00474    * calling jpeg_start_decompress; otherwise a colormap is created during
+00475    * jpeg_start_decompress or jpeg_start_output.
+00476    * The map has out_color_components rows and actual_number_of_colors columns.
+00477    */
+00478   int actual_number_of_colors;  /* number of entries in use */
+00479   JSAMPARRAY colormap;          /* The color map as a 2-D pixel array */
+00480 
+00481   /* State variables: these variables indicate the progress of decompression.
+00482    * The application may examine these but must not modify them.
+00483    */
+00484 
+00485   /* Row index of next scanline to be read from jpeg_read_scanlines().
+00486    * Application may use this to control its processing loop, e.g.,
+00487    * "while (output_scanline < output_height)".
+00488    */
+00489   JDIMENSION output_scanline;   /* 0 .. output_height-1  */
+00490 
+00491   /* Current input scan number and number of iMCU rows completed in scan.
+00492    * These indicate the progress of the decompressor input side.
+00493    */
+00494   int input_scan_number;        /* Number of SOS markers seen so far */
+00495   JDIMENSION input_iMCU_row;    /* Number of iMCU rows completed */
+00496 
+00497   /* The "output scan number" is the notional scan being displayed by the
+00498    * output side.  The decompressor will not allow output scan/row number
+00499    * to get ahead of input scan/row, but it can fall arbitrarily far behind.
+00500    */
+00501   int output_scan_number;       /* Nominal scan number being displayed */
+00502   JDIMENSION output_iMCU_row;   /* Number of iMCU rows read */
+00503 
+00504   /* Current progression status.  coef_bits[c][i] indicates the precision
+00505    * with which component c's DCT coefficient i (in zigzag order) is known.
+00506    * It is -1 when no data has yet been received, otherwise it is the point
+00507    * transform (shift) value for the most recent scan of the coefficient
+00508    * (thus, 0 at completion of the progression).
+00509    * This pointer is NULL when reading a non-progressive file.
+00510    */
+00511   int (*coef_bits)[DCTSIZE2];   /* -1 or current Al value for each coef */
+00512 
+00513   /* Internal JPEG parameters --- the application usually need not look at
+00514    * these fields.  Note that the decompressor output side may not use
+00515    * any parameters that can change between scans.
+00516    */
+00517 
+00518   /* Quantization and Huffman tables are carried forward across input
+00519    * datastreams when processing abbreviated JPEG datastreams.
+00520    */
+00521 
+00522   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
+00523   /* ptrs to coefficient quantization tables, or NULL if not defined */
+00524 
+00525   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
+00526   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
+00527   /* ptrs to Huffman coding tables, or NULL if not defined */
+00528 
+00529   /* These parameters are never carried across datastreams, since they
+00530    * are given in SOF/SOS markers or defined to be reset by SOI.
+00531    */
+00532 
+00533   int data_precision;           /* bits of precision in image data */
+00534 
+00535   jpeg_component_info * comp_info;
+00536   /* comp_info[i] describes component that appears i'th in SOF */
+00537 
+00538   boolean progressive_mode;     /* TRUE if SOFn specifies progressive mode */
+00539   boolean arith_code;           /* TRUE=arithmetic coding, FALSE=Huffman */
+00540 
+00541   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
+00542   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
+00543   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
+00544 
+00545   unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
+00546 
+00547   /* These fields record data obtained from optional markers recognized by
+00548    * the JPEG library.
+00549    */
+00550   boolean saw_JFIF_marker;      /* TRUE iff a JFIF APP0 marker was found */
+00551   /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
+00552   UINT8 JFIF_major_version;     /* JFIF version number */
+00553   UINT8 JFIF_minor_version;
+00554   UINT8 density_unit;           /* JFIF code for pixel size units */
+00555   UINT16 X_density;             /* Horizontal pixel density */
+00556   UINT16 Y_density;             /* Vertical pixel density */
+00557   boolean saw_Adobe_marker;     /* TRUE iff an Adobe APP14 marker was found */
+00558   UINT8 Adobe_transform;        /* Color transform code from Adobe marker */
+00559 
+00560   boolean CCIR601_sampling;     /* TRUE=first samples are cosited */
+00561 
+00562   /* Aside from the specific data retained from APPn markers known to the
+00563    * library, the uninterpreted contents of any or all APPn and COM markers
+00564    * can be saved in a list for examination by the application.
+00565    */
+00566   jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
+00567 
+00568   /* Remaining fields are known throughout decompressor, but generally
+00569    * should not be touched by a surrounding application.
+00570    */
+00571 
+00572   /*
+00573    * These fields are computed during decompression startup
+00574    */
+00575   int max_h_samp_factor;        /* largest h_samp_factor */
+00576   int max_v_samp_factor;        /* largest v_samp_factor */
+00577 
+00578   int min_DCT_scaled_size;      /* smallest DCT_scaled_size of any component */
+00579 
+00580   JDIMENSION total_iMCU_rows;   /* # of iMCU rows in image */
+00581   /* The coefficient controller's input and output progress is measured in
+00582    * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows
+00583    * in fully interleaved JPEG scans, but are used whether the scan is
+00584    * interleaved or not.  We define an iMCU row as v_samp_factor DCT block
+00585    * rows of each component.  Therefore, the IDCT output contains
+00586    * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.
+00587    */
+00588 
+00589   JSAMPLE * sample_range_limit; /* table for fast range-limiting */
+00590 
+00591   /*
+00592    * These fields are valid during any one scan.
+00593    * They describe the components and MCUs actually appearing in the scan.
+00594    * Note that the decompressor output side must not use these fields.
+00595    */
+00596   int comps_in_scan;            /* # of JPEG components in this scan */
+00597   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
+00598   /* *cur_comp_info[i] describes component that appears i'th in SOS */
+00599 
+00600   JDIMENSION MCUs_per_row;      /* # of MCUs across the image */
+00601   JDIMENSION MCU_rows_in_scan;  /* # of MCU rows in the image */
+00602 
+00603   int blocks_in_MCU;            /* # of DCT blocks per MCU */
+00604   int MCU_membership[D_MAX_BLOCKS_IN_MCU];
+00605   /* MCU_membership[i] is index in cur_comp_info of component owning */
+00606   /* i'th block in an MCU */
+00607 
+00608   int Ss, Se, Ah, Al;           /* progressive JPEG parameters for scan */
+00609 
+00610   /* This field is shared between entropy decoder and marker parser.
+00611    * It is either zero or the code of a JPEG marker that has been
+00612    * read from the data source, but has not yet been processed.
+00613    */
+00614   int unread_marker;
+00615 
+00616   /*
+00617    * Links to decompression subobjects (methods, private variables of modules)
+00618    */
+00619   struct jpeg_decomp_master * master;
+00620   struct jpeg_d_main_controller * main;
+00621   struct jpeg_d_coef_controller * coef;
+00622   struct jpeg_d_post_controller * post;
+00623   struct jpeg_input_controller * inputctl;
+00624   struct jpeg_marker_reader * marker;
+00625   struct jpeg_entropy_decoder * entropy;
+00626   struct jpeg_inverse_dct * idct;
+00627   struct jpeg_upsampler * upsample;
+00628   struct jpeg_color_deconverter * cconvert;
+00629   struct jpeg_color_quantizer * cquantize;
+00630 };
+00631 
+00632 
+00633 /* "Object" declarations for JPEG modules that may be supplied or called
+00634  * directly by the surrounding application.
+00635  * As with all objects in the JPEG library, these structs only define the
+00636  * publicly visible methods and state variables of a module.  Additional
+00637  * private fields may exist after the public ones.
+00638  */
+00639 
+00640 
+00641 /* Error handler object */
+00642 
+00643 struct jpeg_error_mgr {
+00644   /* Error exit handler: does not return to caller */
+00645   JMETHOD(void, error_exit, (j_common_ptr cinfo));
+00646   /* Conditionally emit a trace or warning message */
+00647   JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
+00648   /* Routine that actually outputs a trace or error message */
+00649   JMETHOD(void, output_message, (j_common_ptr cinfo));
+00650   /* Format a message string for the most recent JPEG error or message */
+00651   JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
+00652 #define JMSG_LENGTH_MAX  200    /* recommended size of format_message buffer */
+00653   /* Reset error state variables at start of a new image */
+00654   JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
+00655   
+00656   /* The message ID code and any parameters are saved here.
+00657    * A message can have one string parameter or up to 8 int parameters.
+00658    */
+00659   int msg_code;
+00660 #define JMSG_STR_PARM_MAX  80
+00661   union {
+00662     int i[8];
+00663     char s[JMSG_STR_PARM_MAX];
+00664   } msg_parm;
+00665   
+00666   /* Standard state variables for error facility */
+00667   
+00668   int trace_level;              /* max msg_level that will be displayed */
+00669   
+00670   /* For recoverable corrupt-data errors, we emit a warning message,
+00671    * but keep going unless emit_message chooses to abort.  emit_message
+00672    * should count warnings in num_warnings.  The surrounding application
+00673    * can check for bad data by seeing if num_warnings is nonzero at the
+00674    * end of processing.
+00675    */
+00676   long num_warnings;            /* number of corrupt-data warnings */
+00677 
+00678   /* These fields point to the table(s) of error message strings.
+00679    * An application can change the table pointer to switch to a different
+00680    * message list (typically, to change the language in which errors are
+00681    * reported).  Some applications may wish to add additional error codes
+00682    * that will be handled by the JPEG library error mechanism; the second
+00683    * table pointer is used for this purpose.
+00684    *
+00685    * First table includes all errors generated by JPEG library itself.
+00686    * Error code 0 is reserved for a "no such error string" message.
+00687    */
+00688   const char * const * jpeg_message_table; /* Library errors */
+00689   int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */
+00690   /* Second table can be added by application (see cjpeg/djpeg for example).
+00691    * It contains strings numbered first_addon_message..last_addon_message.
+00692    */
+00693   const char * const * addon_message_table; /* Non-library errors */
+00694   int first_addon_message;      /* code for first string in addon table */
+00695   int last_addon_message;       /* code for last string in addon table */
+00696 };
+00697 
+00698 
+00699 /* Progress monitor object */
+00700 
+00701 struct jpeg_progress_mgr {
+00702   JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
+00703 
+00704   long pass_counter;            /* work units completed in this pass */
+00705   long pass_limit;              /* total number of work units in this pass */
+00706   int completed_passes;         /* passes completed so far */
+00707   int total_passes;             /* total number of passes expected */
+00708 };
+00709 
+00710 
+00711 /* Data destination object for compression */
+00712 
+00713 struct jpeg_destination_mgr {
+00714   JOCTET * next_output_byte;    /* => next byte to write in buffer */
+00715   size_t free_in_buffer;        /* # of byte spaces remaining in buffer */
+00716 
+00717   JMETHOD(void, init_destination, (j_compress_ptr cinfo));
+00718   JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
+00719   JMETHOD(void, term_destination, (j_compress_ptr cinfo));
+00720 };
+00721 
+00722 
+00723 /* Data source object for decompression */
+00724 
+00725 struct jpeg_source_mgr {
+00726   const JOCTET * next_input_byte; /* => next byte to read from buffer */
+00727   size_t bytes_in_buffer;       /* # of bytes remaining in buffer */
+00728 
+00729   JMETHOD(void, init_source, (j_decompress_ptr cinfo));
+00730   JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
+00731   JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
+00732   JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
+00733   JMETHOD(void, term_source, (j_decompress_ptr cinfo));
+00734 };
+00735 
+00736 
+00737 /* Memory manager object.
+00738  * Allocates "small" objects (a few K total), "large" objects (tens of K),
+00739  * and "really big" objects (virtual arrays with backing store if needed).
+00740  * The memory manager does not allow individual objects to be freed; rather,
+00741  * each created object is assigned to a pool, and whole pools can be freed
+00742  * at once.  This is faster and more convenient than remembering exactly what
+00743  * to free, especially where malloc()/free() are not too speedy.
+00744  * NB: alloc routines never return NULL.  They exit to error_exit if not
+00745  * successful.
+00746  */
+00747 
+00748 #define JPOOL_PERMANENT 0       /* lasts until master record is destroyed */
+00749 #define JPOOL_IMAGE     1       /* lasts until done with image/datastream */
+00750 #define JPOOL_NUMPOOLS  2
+00751 
+00752 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
+00753 typedef struct jvirt_barray_control * jvirt_barray_ptr;
+00754 
+00755 
+00756 struct jpeg_memory_mgr {
+00757   /* Method pointers */
+00758   JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
+00759                                 size_t sizeofobject));
+00760   JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
+00761                                      size_t sizeofobject));
+00762   JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
+00763                                      JDIMENSION samplesperrow,
+00764                                      JDIMENSION numrows));
+00765   JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
+00766                                       JDIMENSION blocksperrow,
+00767                                       JDIMENSION numrows));
+00768   JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
+00769                                                   int pool_id,
+00770                                                   boolean pre_zero,
+00771                                                   JDIMENSION samplesperrow,
+00772                                                   JDIMENSION numrows,
+00773                                                   JDIMENSION maxaccess));
+00774   JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
+00775                                                   int pool_id,
+00776                                                   boolean pre_zero,
+00777                                                   JDIMENSION blocksperrow,
+00778                                                   JDIMENSION numrows,
+00779                                                   JDIMENSION maxaccess));
+00780   JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
+00781   JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
+00782                                            jvirt_sarray_ptr ptr,
+00783                                            JDIMENSION start_row,
+00784                                            JDIMENSION num_rows,
+00785                                            boolean writable));
+00786   JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
+00787                                             jvirt_barray_ptr ptr,
+00788                                             JDIMENSION start_row,
+00789                                             JDIMENSION num_rows,
+00790                                             boolean writable));
+00791   JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
+00792   JMETHOD(void, self_destruct, (j_common_ptr cinfo));
+00793 
+00794   /* Limit on memory allocation for this JPEG object.  (Note that this is
+00795    * merely advisory, not a guaranteed maximum; it only affects the space
+00796    * used for virtual-array buffers.)  May be changed by outer application
+00797    * after creating the JPEG object.
+00798    */
+00799   long max_memory_to_use;
+00800 
+00801   /* Maximum allocation request accepted by alloc_large. */
+00802   long max_alloc_chunk;
+00803 };
+00804 
+00805 
+00806 /* Routine signature for application-supplied marker processing methods.
+00807  * Need not pass marker code since it is stored in cinfo->unread_marker.
+00808  */
+00809 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
+00810 
+00811 
+00812 /* Declarations for routines called by application.
+00813  * The JPP macro hides prototype parameters from compilers that can't cope.
+00814  * Note JPP requires double parentheses.
+00815  */
+00816 
+00817 #ifdef HAVE_PROTOTYPES
+00818 #define JPP(arglist)    arglist
+00819 #else
+00820 #define JPP(arglist)    ()
+00821 #endif
+00822 
+00823 
+00824 /* Short forms of external names for systems with brain-damaged linkers.
+00825  * We shorten external names to be unique in the first six letters, which
+00826  * is good enough for all known systems.
+00827  * (If your compiler itself needs names to be unique in less than 15 
+00828  * characters, you are out of luck.  Get a better compiler.)
+00829  */
+00830 
+00831 #ifdef NEED_SHORT_EXTERNAL_NAMES
+00832 #define jpeg_std_error          jStdError
+00833 #define jpeg_CreateCompress     jCreaCompress
+00834 #define jpeg_CreateDecompress   jCreaDecompress
+00835 #define jpeg_destroy_compress   jDestCompress
+00836 #define jpeg_destroy_decompress jDestDecompress
+00837 #define jpeg_stdio_dest         jStdDest
+00838 #define jpeg_stdio_src          jStdSrc
+00839 #define jpeg_set_defaults       jSetDefaults
+00840 #define jpeg_set_colorspace     jSetColorspace
+00841 #define jpeg_default_colorspace jDefColorspace
+00842 #define jpeg_set_quality        jSetQuality
+00843 #define jpeg_set_linear_quality jSetLQuality
+00844 #define jpeg_add_quant_table    jAddQuantTable
+00845 #define jpeg_quality_scaling    jQualityScaling
+00846 #define jpeg_simple_progression jSimProgress
+00847 #define jpeg_suppress_tables    jSuppressTables
+00848 #define jpeg_alloc_quant_table  jAlcQTable
+00849 #define jpeg_alloc_huff_table   jAlcHTable
+00850 #define jpeg_start_compress     jStrtCompress
+00851 #define jpeg_write_scanlines    jWrtScanlines
+00852 #define jpeg_finish_compress    jFinCompress
+00853 #define jpeg_write_raw_data     jWrtRawData
+00854 #define jpeg_write_marker       jWrtMarker
+00855 #define jpeg_write_m_header     jWrtMHeader
+00856 #define jpeg_write_m_byte       jWrtMByte
+00857 #define jpeg_write_tables       jWrtTables
+00858 #define jpeg_read_header        jReadHeader
+00859 #define jpeg_start_decompress   jStrtDecompress
+00860 #define jpeg_read_scanlines     jReadScanlines
+00861 #define jpeg_finish_decompress  jFinDecompress
+00862 #define jpeg_read_raw_data      jReadRawData
+00863 #define jpeg_has_multiple_scans jHasMultScn
+00864 #define jpeg_start_output       jStrtOutput
+00865 #define jpeg_finish_output      jFinOutput
+00866 #define jpeg_input_complete     jInComplete
+00867 #define jpeg_new_colormap       jNewCMap
+00868 #define jpeg_consume_input      jConsumeInput
+00869 #define jpeg_calc_output_dimensions     jCalcDimensions
+00870 #define jpeg_save_markers       jSaveMarkers
+00871 #define jpeg_set_marker_processor       jSetMarker
+00872 #define jpeg_read_coefficients  jReadCoefs
+00873 #define jpeg_write_coefficients jWrtCoefs
+00874 #define jpeg_copy_critical_parameters   jCopyCrit
+00875 #define jpeg_abort_compress     jAbrtCompress
+00876 #define jpeg_abort_decompress   jAbrtDecompress
+00877 #define jpeg_abort              jAbort
+00878 #define jpeg_destroy            jDestroy
+00879 #define jpeg_resync_to_restart  jResyncRestart
+00880 #endif /* NEED_SHORT_EXTERNAL_NAMES */
+00881 
+00882 
+00883 /* Default error-management setup */
+00884 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
+00885         JPP((struct jpeg_error_mgr * err));
+00886 
+00887 /* Initialization of JPEG compression objects.
+00888  * jpeg_create_compress() and jpeg_create_decompress() are the exported
+00889  * names that applications should call.  These expand to calls on
+00890  * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
+00891  * passed for version mismatch checking.
+00892  * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
+00893  */
+00894 #define jpeg_create_compress(cinfo) \
+00895     jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
+00896                         (size_t) sizeof(struct jpeg_compress_struct))
+00897 #define jpeg_create_decompress(cinfo) \
+00898     jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
+00899                           (size_t) sizeof(struct jpeg_decompress_struct))
+00900 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
+00901                                       int version, size_t structsize));
+00902 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
+00903                                         int version, size_t structsize));
+00904 /* Destruction of JPEG compression objects */
+00905 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
+00906 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
+00907 
+00908 /* Standard data source and destination managers: stdio streams. */
+00909 /* Caller is responsible for opening the file before and closing after. */
+00910 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
+00911 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
+00912 
+00913 /* Default parameter setup for compression */
+00914 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
+00915 /* Compression parameter setup aids */
+00916 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
+00917                                       J_COLOR_SPACE colorspace));
+00918 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
+00919 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
+00920                                    boolean force_baseline));
+00921 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
+00922                                           int scale_factor,
+00923                                           boolean force_baseline));
+00924 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
+00925                                        const unsigned int *basic_table,
+00926                                        int scale_factor,
+00927                                        boolean force_baseline));
+00928 EXTERN(int) jpeg_quality_scaling JPP((int quality));
+00929 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
+00930 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
+00931                                        boolean suppress));
+00932 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
+00933 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
+00934 
+00935 /* Main entry points for compression */
+00936 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
+00937                                       boolean write_all_tables));
+00938 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
+00939                                              JSAMPARRAY scanlines,
+00940                                              JDIMENSION num_lines));
+00941 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
+00942 
+00943 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
+00944 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
+00945                                             JSAMPIMAGE data,
+00946                                             JDIMENSION num_lines));
+00947 
+00948 /* Write a special marker.  See libjpeg.doc concerning safe usage. */
+00949 EXTERN(void) jpeg_write_marker
+00950         JPP((j_compress_ptr cinfo, int marker,
+00951              const JOCTET * dataptr, unsigned int datalen));
+00952 /* Same, but piecemeal. */
+00953 EXTERN(void) jpeg_write_m_header
+00954         JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
+00955 EXTERN(void) jpeg_write_m_byte
+00956         JPP((j_compress_ptr cinfo, int val));
+00957 
+00958 /* Alternate compression function: just write an abbreviated table file */
+00959 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
+00960 
+00961 /* Decompression startup: read start of JPEG datastream to see what's there */
+00962 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
+00963                                   boolean require_image));
+00964 /* Return value is one of: */
+00965 #define JPEG_SUSPENDED          0 /* Suspended due to lack of input data */
+00966 #define JPEG_HEADER_OK          1 /* Found valid image datastream */
+00967 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
+00968 /* If you pass require_image = TRUE (normal case), you need not check for
+00969  * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
+00970  * JPEG_SUSPENDED is only possible if you use a data source module that can
+00971  * give a suspension return (the stdio source module doesn't).
+00972  */
+00973 
+00974 /* Main entry points for decompression */
+00975 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
+00976 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
+00977                                             JSAMPARRAY scanlines,
+00978                                             JDIMENSION max_lines));
+00979 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
+00980 
+00981 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
+00982 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
+00983                                            JSAMPIMAGE data,
+00984                                            JDIMENSION max_lines));
+00985 
+00986 /* Additional entry points for buffered-image mode. */
+00987 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
+00988 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
+00989                                        int scan_number));
+00990 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
+00991 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
+00992 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
+00993 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
+00994 /* Return value is one of: */
+00995 /* #define JPEG_SUSPENDED       0    Suspended due to lack of input data */
+00996 #define JPEG_REACHED_SOS        1 /* Reached start of new scan */
+00997 #define JPEG_REACHED_EOI        2 /* Reached end of image */
+00998 #define JPEG_ROW_COMPLETED      3 /* Completed one iMCU row */
+00999 #define JPEG_SCAN_COMPLETED     4 /* Completed last iMCU row of a scan */
+01000 
+01001 /* Precalculate output dimensions for current decompression parameters. */
+01002 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
+01003 
+01004 /* Control saving of COM and APPn markers into marker_list. */
+01005 EXTERN(void) jpeg_save_markers
+01006         JPP((j_decompress_ptr cinfo, int marker_code,
+01007              unsigned int length_limit));
+01008 
+01009 /* Install a special processing method for COM or APPn markers. */
+01010 EXTERN(void) jpeg_set_marker_processor
+01011         JPP((j_decompress_ptr cinfo, int marker_code,
+01012              jpeg_marker_parser_method routine));
+01013 
+01014 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
+01015 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
+01016 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
+01017                                           jvirt_barray_ptr * coef_arrays));
+01018 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
+01019                                                 j_compress_ptr dstinfo));
+01020 
+01021 /* If you choose to abort compression or decompression before completing
+01022  * jpeg_finish_(de)compress, then you need to clean up to release memory,
+01023  * temporary files, etc.  You can just call jpeg_destroy_(de)compress
+01024  * if you're done with the JPEG object, but if you want to clean it up and
+01025  * reuse it, call this:
+01026  */
+01027 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
+01028 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
+01029 
+01030 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
+01031  * flavor of JPEG object.  These may be more convenient in some places.
+01032  */
+01033 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
+01034 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
+01035 
+01036 /* Default restart-marker-resync procedure for use by data source modules */
+01037 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
+01038                                             int desired));
+01039 
+01040 
+01041 /* These marker codes are exported since applications and data source modules
+01042  * are likely to want to use them.
+01043  */
+01044 
+01045 #define JPEG_RST0       0xD0    /* RST0 marker code */
+01046 #define JPEG_EOI        0xD9    /* EOI marker code */
+01047 #define JPEG_APP0       0xE0    /* APP0 marker code */
+01048 #define JPEG_COM        0xFE    /* COM marker code */
+01049 
+01050 
+01051 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
+01052  * for structure definitions that are never filled in, keep it quiet by
+01053  * supplying dummy definitions for the various substructures.
+01054  */
+01055 
+01056 #ifdef INCOMPLETE_TYPES_BROKEN
+01057 #ifndef JPEG_INTERNALS          /* will be defined in jpegint.h */
+01058 struct jvirt_sarray_control { long dummy; };
+01059 struct jvirt_barray_control { long dummy; };
+01060 struct jpeg_comp_master { long dummy; };
+01061 struct jpeg_c_main_controller { long dummy; };
+01062 struct jpeg_c_prep_controller { long dummy; };
+01063 struct jpeg_c_coef_controller { long dummy; };
+01064 struct jpeg_marker_writer { long dummy; };
+01065 struct jpeg_color_converter { long dummy; };
+01066 struct jpeg_downsampler { long dummy; };
+01067 struct jpeg_forward_dct { long dummy; };
+01068 struct jpeg_entropy_encoder { long dummy; };
+01069 struct jpeg_decomp_master { long dummy; };
+01070 struct jpeg_d_main_controller { long dummy; };
+01071 struct jpeg_d_coef_controller { long dummy; };
+01072 struct jpeg_d_post_controller { long dummy; };
+01073 struct jpeg_input_controller { long dummy; };
+01074 struct jpeg_marker_reader { long dummy; };
+01075 struct jpeg_entropy_decoder { long dummy; };
+01076 struct jpeg_inverse_dct { long dummy; };
+01077 struct jpeg_upsampler { long dummy; };
+01078 struct jpeg_color_deconverter { long dummy; };
+01079 struct jpeg_color_quantizer { long dummy; };
+01080 #endif /* JPEG_INTERNALS */
+01081 #endif /* INCOMPLETE_TYPES_BROKEN */
+01082 
+01083 
+01084 /*
+01085  * The JPEG library modules define JPEG_INTERNALS before including this file.
+01086  * The internal structure declarations are read only when that is true.
+01087  * Applications using the library should not include jpegint.h, but may wish
+01088  * to include jerror.h.
+01089  */
+01090 
+01091 #ifdef JPEG_INTERNALS
+01092 #include "jpegint.h"            /* fetch private declarations */
+01093 #include "jerror.h"             /* fetch error codes too */
+01094 #endif
+01095 
+01096 #endif /* JPEGLIB_H */
+