Back to index

lightning-sunbird  0.9+nobinonly
jpeglib.h
Go to the documentation of this file.
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 #ifdef XP_OS2
00017 /*
00018  * On OS/2, the system will have defined RGB_* so we #undef 'em to avoid warnings
00019  * from jmorecfg.h.
00020  */
00021 #ifdef RGB_RED
00022        #undef RGB_RED
00023 #endif
00024 #ifdef RGB_GREEN
00025        #undef RGB_GREEN
00026 #endif
00027 #ifdef RGB_BLUE
00028        #undef RGB_BLUE
00029 #endif
00030 
00031 #endif
00032 
00033 /*
00034  * First we include the configuration files that record how this
00035  * installation of the JPEG library is set up.  jconfig.h can be
00036  * generated automatically for many systems.  jmorecfg.h contains
00037  * manual configuration options that most people need not worry about.
00038  */
00039 
00040 #ifndef JCONFIG_INCLUDED    /* in case jinclude.h already did */
00041 #include "jconfig.h"        /* widely used configuration options */
00042 #endif
00043 #include "jmorecfg.h"              /* seldom changed options */
00044 
00045 
00046 #ifdef HAVE_MMX_INTEL_MNEMONICS
00047        extern int MMXAvailable;
00048 #endif
00049 
00050 
00051 /* Version ID for the JPEG library.
00052  * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
00053  */
00054 
00055 #define JPEG_LIB_VERSION  62       /* Version 6b */
00056 
00057 
00058 /* Various constants determining the sizes of things.
00059  * All of these are specified by the JPEG standard, so don't change them
00060  * if you want to be compatible.
00061  */
00062 
00063 #define DCTSIZE                 8  /* The basic DCT block is 8x8 samples */
00064 #define DCTSIZE2         64 /* DCTSIZE squared; # of elements in a block */
00065 #define NUM_QUANT_TBLS      4      /* Quantization tables are numbered 0..3 */
00066 #define NUM_HUFF_TBLS       4      /* Huffman tables are numbered 0..3 */
00067 #define NUM_ARITH_TBLS      16     /* Arith-coding tables are numbered 0..15 */
00068 #define MAX_COMPS_IN_SCAN   4      /* JPEG limit on # of components in one scan */
00069 #define MAX_SAMP_FACTOR     4      /* JPEG limit on sampling factors */
00070 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
00071  * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
00072  * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
00073  * to handle it.  We even let you do this from the jconfig.h file.  However,
00074  * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
00075  * sometimes emits noncompliant files doesn't mean you should too.
00076  */
00077 #define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
00078 #ifndef D_MAX_BLOCKS_IN_MCU
00079 #define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
00080 #endif
00081 
00082 
00083 /* Data structures for images (arrays of samples and of DCT coefficients).
00084  * On 80x86 machines, the image arrays are too big for near pointers,
00085  * but the pointer arrays can fit in near memory.
00086  */
00087 
00088 typedef JSAMPLE FAR *JSAMPROW;     /* ptr to one image row of pixel samples. */
00089 typedef JSAMPROW *JSAMPARRAY;      /* ptr to some rows (a 2-D sample array) */
00090 typedef JSAMPARRAY *JSAMPIMAGE;    /* a 3-D sample array: top index is color */
00091 
00092 typedef JCOEF JBLOCK[DCTSIZE2];    /* one block of coefficients */
00093 typedef JBLOCK FAR *JBLOCKROW;     /* pointer to one row of coefficient blocks */
00094 typedef JBLOCKROW *JBLOCKARRAY;           /* a 2-D array of coefficient blocks */
00095 typedef JBLOCKARRAY *JBLOCKIMAGE;  /* a 3-D array of coefficient blocks */
00096 
00097 typedef JCOEF FAR *JCOEFPTR;       /* useful in a couple of places */
00098 
00099 
00100 /* Types for JPEG compression parameters and working tables. */
00101 
00102 
00103 /* DCT coefficient quantization tables. */
00104 
00105 typedef struct {
00106   /* This array gives the coefficient quantizers in natural array order
00107    * (not the zigzag order in which they are stored in a JPEG DQT marker).
00108    * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
00109    */
00110   UINT16 quantval[DCTSIZE2];       /* quantization step for each coefficient */
00111   /* This field is used only during compression.  It's initialized FALSE when
00112    * the table is created, and set TRUE when it's been output to the file.
00113    * You could suppress output of a table by setting this to TRUE.
00114    * (See jpeg_suppress_tables for an example.)
00115    */
00116   boolean sent_table;              /* TRUE when table has been output */
00117 } JQUANT_TBL;
00118 
00119 
00120 /* Huffman coding tables. */
00121 
00122 typedef struct {
00123   /* These two fields directly represent the contents of a JPEG DHT marker */
00124   UINT8 bits[17];           /* bits[k] = # of symbols with codes of */
00125                             /* length k bits; bits[0] is unused */
00126   UINT8 huffval[256];              /* The symbols, in order of incr code length */
00127   /* This field is used only during compression.  It's initialized FALSE when
00128    * the table is created, and set TRUE when it's been output to the file.
00129    * You could suppress output of a table by setting this to TRUE.
00130    * (See jpeg_suppress_tables for an example.)
00131    */
00132   boolean sent_table;              /* TRUE when table has been output */
00133 } JHUFF_TBL;
00134 
00135 
00136 /* Basic info about one component (color channel). */
00137 
00138 typedef struct {
00139   /* These values are fixed over the whole image. */
00140   /* For compression, they must be supplied by parameter setup; */
00141   /* for decompression, they are read from the SOF marker. */
00142   int component_id;         /* identifier for this component (0..255) */
00143   int component_index;             /* its index in SOF or cinfo->comp_info[] */
00144   int h_samp_factor;        /* horizontal sampling factor (1..4) */
00145   int v_samp_factor;        /* vertical sampling factor (1..4) */
00146   int quant_tbl_no;         /* quantization table selector (0..3) */
00147   /* These values may vary between scans. */
00148   /* For compression, they must be supplied by parameter setup; */
00149   /* for decompression, they are read from the SOS marker. */
00150   /* The decompressor output side may not use these variables. */
00151   int dc_tbl_no;            /* DC entropy table selector (0..3) */
00152   int ac_tbl_no;            /* AC entropy table selector (0..3) */
00153   
00154   /* Remaining fields should be treated as private by applications. */
00155   
00156   /* These values are computed during compression or decompression startup: */
00157   /* Component's size in DCT blocks.
00158    * Any dummy blocks added to complete an MCU are not counted; therefore
00159    * these values do not depend on whether a scan is interleaved or not.
00160    */
00161   JDIMENSION width_in_blocks;
00162   JDIMENSION height_in_blocks;
00163   /* Size of a DCT block in samples.  Always DCTSIZE for compression.
00164    * For decompression this is the size of the output from one DCT block,
00165    * reflecting any scaling we choose to apply during the IDCT step.
00166    * Values of 1,2,4,8 are likely to be supported.  Note that different
00167    * components may receive different IDCT scalings.
00168    */
00169   int DCT_scaled_size;
00170   /* The downsampled dimensions are the component's actual, unpadded number
00171    * of samples at the main buffer (preprocessing/compression interface), thus
00172    * downsampled_width = ceil(image_width * Hi/Hmax)
00173    * and similarly for height.  For decompression, IDCT scaling is included, so
00174    * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
00175    */
00176   JDIMENSION downsampled_width;     /* actual width in samples */
00177   JDIMENSION downsampled_height; /* actual height in samples */
00178   /* This flag is used only for decompression.  In cases where some of the
00179    * components will be ignored (eg grayscale output from YCbCr image),
00180    * we can skip most computations for the unused components.
00181    */
00182   boolean component_needed; /* do we need the value of this component? */
00183 
00184   /* These values are computed before starting a scan of the component. */
00185   /* The decompressor output side may not use these variables. */
00186   int MCU_width;            /* number of blocks per MCU, horizontally */
00187   int MCU_height;           /* number of blocks per MCU, vertically */
00188   int MCU_blocks;           /* MCU_width * MCU_height */
00189   int MCU_sample_width;            /* MCU width in samples, MCU_width*DCT_scaled_size */
00190   int last_col_width;              /* # of non-dummy blocks across in last MCU */
00191   int last_row_height;             /* # of non-dummy blocks down in last MCU */
00192 
00193   /* Saved quantization table for component; NULL if none yet saved.
00194    * See jdinput.c comments about the need for this information.
00195    * This field is currently used only for decompression.
00196    */
00197   JQUANT_TBL * quant_table;
00198 
00199   /* Private per-component storage for DCT or IDCT subsystem. */
00200   void * dct_table;
00201 } jpeg_component_info;
00202 
00203 
00204 /* The script for encoding a multiple-scan file is an array of these: */
00205 
00206 typedef struct {
00207   int comps_in_scan;        /* number of components encoded in this scan */
00208   int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
00209   int Ss, Se;               /* progressive JPEG spectral selection parms */
00210   int Ah, Al;               /* progressive JPEG successive approx. parms */
00211 } jpeg_scan_info;
00212 
00213 /* The decompressor can save APPn and COM markers in a list of these: */
00214 
00215 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
00216 
00217 struct jpeg_marker_struct {
00218   jpeg_saved_marker_ptr next;      /* next in list, or NULL */
00219   UINT8 marker;                    /* marker code: JPEG_COM, or JPEG_APP0+n */
00220   unsigned int original_length;    /* # bytes of data in the file */
00221   unsigned int data_length; /* # bytes of data saved at data[] */
00222   JOCTET FAR * data;        /* the data contained in the marker */
00223   /* the marker length word is not counted in data_length or original_length */
00224 };
00225 
00226 /* Known color spaces. */
00227 
00228 typedef enum {
00229        JCS_UNKNOWN,         /* error/unspecified */
00230        JCS_GRAYSCALE,              /* monochrome */
00231        JCS_RGB,             /* red/green/blue */
00232        JCS_YCbCr,           /* Y/Cb/Cr (also known as YUV) */
00233        JCS_CMYK,            /* C/M/Y/K */
00234        JCS_YCCK             /* Y/Cb/Cr/K */
00235 } J_COLOR_SPACE;
00236 
00237 /* DCT/IDCT algorithm options. */
00238 
00239 typedef enum {
00240        JDCT_ISLOW,          /* slow but accurate integer algorithm */
00241        JDCT_IFAST,          /* faster, less accurate integer method */
00242        JDCT_FLOAT           /* floating-point: accurate, fast on fast HW */
00243 } J_DCT_METHOD;
00244 
00245 #ifndef JDCT_DEFAULT        /* may be overridden in jconfig.h */
00246 #define JDCT_DEFAULT  JDCT_ISLOW
00247 #endif
00248 #ifndef JDCT_FASTEST        /* may be overridden in jconfig.h */
00249 #define JDCT_FASTEST  JDCT_IFAST
00250 #endif
00251 
00252 /* Dithering options for decompression. */
00253 
00254 typedef enum {
00255        JDITHER_NONE,        /* no dithering */
00256        JDITHER_ORDERED,     /* simple ordered dither */
00257        JDITHER_FS           /* Floyd-Steinberg error diffusion dither */
00258 } J_DITHER_MODE;
00259 
00260 
00261 /* Common fields between JPEG compression and decompression master structs. */
00262 
00263 #define jpeg_common_fields \
00264   struct jpeg_error_mgr * err;     /* Error handler module */\
00265   struct jpeg_memory_mgr * mem;    /* Memory manager module */\
00266   struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
00267   void * client_data;              /* Available for use by application */\
00268   boolean is_decompressor;  /* So common code can tell which is which */\
00269   int global_state          /* For checking call sequence validity */
00270 
00271 /* Routines that are to be used by both halves of the library are declared
00272  * to receive a pointer to this structure.  There are no actual instances of
00273  * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
00274  */
00275 struct jpeg_common_struct {
00276   jpeg_common_fields;              /* Fields common to both master struct types */
00277   /* Additional fields follow in an actual jpeg_compress_struct or
00278    * jpeg_decompress_struct.  All three structs must agree on these
00279    * initial fields!  (This would be a lot cleaner in C++.)
00280    */
00281 };
00282 
00283 typedef struct jpeg_common_struct * j_common_ptr;
00284 typedef struct jpeg_compress_struct * j_compress_ptr;
00285 typedef struct jpeg_decompress_struct * j_decompress_ptr;
00286 
00287 
00288 /* Master record for a compression instance */
00289 
00290 struct jpeg_compress_struct {
00291   jpeg_common_fields;              /* Fields shared with jpeg_decompress_struct */
00292 
00293   /* Destination for compressed data */
00294   struct jpeg_destination_mgr * dest;
00295 
00296   /* Description of source image --- these fields must be filled in by
00297    * outer application before starting compression.  in_color_space must
00298    * be correct before you can even call jpeg_set_defaults().
00299    */
00300 
00301   JDIMENSION image_width;   /* input image width */
00302   JDIMENSION image_height;  /* input image height */
00303   int input_components;            /* # of color components in input image */
00304   J_COLOR_SPACE in_color_space;    /* colorspace of input image */
00305 
00306   double input_gamma;              /* image gamma of input image */
00307 
00308   /* Compression parameters --- these fields must be set before calling
00309    * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to
00310    * initialize everything to reasonable defaults, then changing anything
00311    * the application specifically wants to change.  That way you won't get
00312    * burnt when new parameters are added.  Also note that there are several
00313    * helper routines to simplify changing parameters.
00314    */
00315 
00316   int data_precision;              /* bits of precision in image data */
00317 
00318   int num_components;              /* # of color components in JPEG image */
00319   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
00320 
00321   jpeg_component_info * comp_info;
00322   /* comp_info[i] describes component that appears i'th in SOF */
00323   
00324   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
00325   /* ptrs to coefficient quantization tables, or NULL if not defined */
00326   
00327   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
00328   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
00329   /* ptrs to Huffman coding tables, or NULL if not defined */
00330   
00331   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
00332   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
00333   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
00334 
00335   int num_scans;            /* # of entries in scan_info array */
00336   const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
00337   /* The default value of scan_info is NULL, which causes a single-scan
00338    * sequential JPEG file to be emitted.  To create a multi-scan file,
00339    * set num_scans and scan_info to point to an array of scan definitions.
00340    */
00341 
00342   boolean raw_data_in;             /* TRUE=caller supplies downsampled data */
00343   boolean arith_code;              /* TRUE=arithmetic coding, FALSE=Huffman */
00344   boolean optimize_coding;  /* TRUE=optimize entropy encoding parms */
00345   boolean CCIR601_sampling; /* TRUE=first samples are cosited */
00346   int smoothing_factor;            /* 1..100, or 0 for no input smoothing */
00347   J_DCT_METHOD dct_method;  /* DCT algorithm selector */
00348 
00349   /* The restart interval can be specified in absolute MCUs by setting
00350    * restart_interval, or in MCU rows by setting restart_in_rows
00351    * (in which case the correct restart_interval will be figured
00352    * for each scan).
00353    */
00354   unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
00355   int restart_in_rows;             /* if > 0, MCU rows per restart interval */
00356 
00357   /* Parameters controlling emission of special markers. */
00358 
00359   boolean write_JFIF_header;       /* should a JFIF marker be written? */
00360   UINT8 JFIF_major_version; /* What to write for the JFIF version number */
00361   UINT8 JFIF_minor_version;
00362   /* These three values are not used by the JPEG code, merely copied */
00363   /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */
00364   /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */
00365   /* ratio is defined by X_density/Y_density even when density_unit=0. */
00366   UINT8 density_unit;              /* JFIF code for pixel size units */
00367   UINT16 X_density;         /* Horizontal pixel density */
00368   UINT16 Y_density;         /* Vertical pixel density */
00369   boolean write_Adobe_marker;      /* should an Adobe marker be written? */
00370   
00371   /* State variable: index of next scanline to be written to
00372    * jpeg_write_scanlines().  Application may use this to control its
00373    * processing loop, e.g., "while (next_scanline < image_height)".
00374    */
00375 
00376   JDIMENSION next_scanline; /* 0 .. image_height-1  */
00377 
00378   /* Remaining fields are known throughout compressor, but generally
00379    * should not be touched by a surrounding application.
00380    */
00381 
00382   /*
00383    * These fields are computed during compression startup
00384    */
00385   boolean progressive_mode; /* TRUE if scan script uses progressive mode */
00386   int max_h_samp_factor;    /* largest h_samp_factor */
00387   int max_v_samp_factor;    /* largest v_samp_factor */
00388 
00389   JDIMENSION total_iMCU_rows;      /* # of iMCU rows to be input to coef ctlr */
00390   /* The coefficient controller receives data in units of MCU rows as defined
00391    * for fully interleaved scans (whether the JPEG file is interleaved or not).
00392    * There are v_samp_factor * DCTSIZE sample rows of each component in an
00393    * "iMCU" (interleaved MCU) row.
00394    */
00395   
00396   /*
00397    * These fields are valid during any one scan.
00398    * They describe the components and MCUs actually appearing in the scan.
00399    */
00400   int comps_in_scan;        /* # of JPEG components in this scan */
00401   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
00402   /* *cur_comp_info[i] describes component that appears i'th in SOS */
00403   
00404   JDIMENSION MCUs_per_row;  /* # of MCUs across the image */
00405   JDIMENSION MCU_rows_in_scan;     /* # of MCU rows in the image */
00406   
00407   int blocks_in_MCU;        /* # of DCT blocks per MCU */
00408   int MCU_membership[C_MAX_BLOCKS_IN_MCU];
00409   /* MCU_membership[i] is index in cur_comp_info of component owning */
00410   /* i'th block in an MCU */
00411 
00412   int Ss, Se, Ah, Al;              /* progressive JPEG parameters for scan */
00413 
00414   /*
00415    * Links to compression subobjects (methods and private variables of modules)
00416    */
00417   struct jpeg_comp_master * master;
00418   struct jpeg_c_main_controller * main;
00419   struct jpeg_c_prep_controller * prep;
00420   struct jpeg_c_coef_controller * coef;
00421   struct jpeg_marker_writer * marker;
00422   struct jpeg_color_converter * cconvert;
00423   struct jpeg_downsampler * downsample;
00424   struct jpeg_forward_dct * fdct;
00425   struct jpeg_entropy_encoder * entropy;
00426   jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
00427   int script_space_size;
00428 };
00429 
00430 
00431 /* Master record for a decompression instance */
00432 
00433 struct jpeg_decompress_struct {
00434   jpeg_common_fields;              /* Fields shared with jpeg_compress_struct */
00435 
00436   /* Source of compressed data */
00437   struct jpeg_source_mgr * src;
00438 
00439   /* Basic description of image --- filled in by jpeg_read_header(). */
00440   /* Application may inspect these values to decide how to process image. */
00441 
00442   JDIMENSION image_width;   /* nominal image width (from SOF marker) */
00443   JDIMENSION image_height;  /* nominal image height */
00444   int num_components;              /* # of color components in JPEG image */
00445   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
00446 
00447   /* Decompression processing parameters --- these fields must be set before
00448    * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes
00449    * them to default values.
00450    */
00451 
00452   J_COLOR_SPACE out_color_space; /* colorspace for output */
00453 
00454   unsigned int scale_num, scale_denom; /* fraction by which to scale image */
00455 
00456   double output_gamma;             /* image gamma wanted in output */
00457 
00458   boolean buffered_image;   /* TRUE=multiple output passes */
00459   boolean raw_data_out;            /* TRUE=downsampled data wanted */
00460 
00461   J_DCT_METHOD dct_method;  /* IDCT algorithm selector */
00462   boolean do_fancy_upsampling;     /* TRUE=apply fancy upsampling */
00463   boolean do_block_smoothing;      /* TRUE=apply interblock smoothing */
00464 
00465   boolean quantize_colors;  /* TRUE=colormapped output wanted */
00466   /* the following are ignored if not quantize_colors: */
00467   J_DITHER_MODE dither_mode;       /* type of color dithering to use */
00468   boolean two_pass_quantize;       /* TRUE=use two-pass color quantization */
00469   int desired_number_of_colors;    /* max # colors to use in created colormap */
00470   /* these are significant only in buffered-image mode: */
00471   boolean enable_1pass_quant;      /* enable future use of 1-pass quantizer */
00472   boolean enable_external_quant;/* enable future use of external colormap */
00473   boolean enable_2pass_quant;      /* enable future use of 2-pass quantizer */
00474 
00475   /* Description of actual output image that will be returned to application.
00476    * These fields are computed by jpeg_start_decompress().
00477    * You can also use jpeg_calc_output_dimensions() to determine these values
00478    * in advance of calling jpeg_start_decompress().
00479    */
00480 
00481   JDIMENSION output_width;  /* scaled image width */
00482   JDIMENSION output_height; /* scaled image height */
00483   int out_color_components; /* # of color components in out_color_space */
00484   int output_components;    /* # of color components returned */
00485   /* output_components is 1 (a colormap index) when quantizing colors;
00486    * otherwise it equals out_color_components.
00487    */
00488   int rec_outbuf_height;    /* min recommended height of scanline buffer */
00489   /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
00490    * high, space and time will be wasted due to unnecessary data copying.
00491    * Usually rec_outbuf_height will be 1 or 2, at most 4.
00492    */
00493 
00494   /* When quantizing colors, the output colormap is described by these fields.
00495    * The application can supply a colormap by setting colormap non-NULL before
00496    * calling jpeg_start_decompress; otherwise a colormap is created during
00497    * jpeg_start_decompress or jpeg_start_output.
00498    * The map has out_color_components rows and actual_number_of_colors columns.
00499    */
00500   int actual_number_of_colors;     /* number of entries in use */
00501   JSAMPARRAY colormap;             /* The color map as a 2-D pixel array */
00502 
00503   /* State variables: these variables indicate the progress of decompression.
00504    * The application may examine these but must not modify them.
00505    */
00506 
00507   /* Row index of next scanline to be read from jpeg_read_scanlines().
00508    * Application may use this to control its processing loop, e.g.,
00509    * "while (output_scanline < output_height)".
00510    */
00511   JDIMENSION output_scanline;      /* 0 .. output_height-1  */
00512 
00513   /* Current input scan number and number of iMCU rows completed in scan.
00514    * These indicate the progress of the decompressor input side.
00515    */
00516   int input_scan_number;    /* Number of SOS markers seen so far */
00517   JDIMENSION input_iMCU_row;       /* Number of iMCU rows completed */
00518 
00519   /* The "output scan number" is the notional scan being displayed by the
00520    * output side.  The decompressor will not allow output scan/row number
00521    * to get ahead of input scan/row, but it can fall arbitrarily far behind.
00522    */
00523   int output_scan_number;   /* Nominal scan number being displayed */
00524   JDIMENSION output_iMCU_row;      /* Number of iMCU rows read */
00525 
00526   /* Current progression status.  coef_bits[c][i] indicates the precision
00527    * with which component c's DCT coefficient i (in zigzag order) is known.
00528    * It is -1 when no data has yet been received, otherwise it is the point
00529    * transform (shift) value for the most recent scan of the coefficient
00530    * (thus, 0 at completion of the progression).
00531    * This pointer is NULL when reading a non-progressive file.
00532    */
00533   int (*coef_bits)[DCTSIZE2];      /* -1 or current Al value for each coef */
00534 
00535   /* Internal JPEG parameters --- the application usually need not look at
00536    * these fields.  Note that the decompressor output side may not use
00537    * any parameters that can change between scans.
00538    */
00539 
00540   /* Quantization and Huffman tables are carried forward across input
00541    * datastreams when processing abbreviated JPEG datastreams.
00542    */
00543 
00544   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
00545   /* ptrs to coefficient quantization tables, or NULL if not defined */
00546 
00547   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
00548   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
00549   /* ptrs to Huffman coding tables, or NULL if not defined */
00550 
00551   /* These parameters are never carried across datastreams, since they
00552    * are given in SOF/SOS markers or defined to be reset by SOI.
00553    */
00554 
00555   int data_precision;              /* bits of precision in image data */
00556 
00557   jpeg_component_info * comp_info;
00558   /* comp_info[i] describes component that appears i'th in SOF */
00559 
00560   boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
00561   boolean arith_code;              /* TRUE=arithmetic coding, FALSE=Huffman */
00562 
00563   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
00564   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
00565   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
00566 
00567   unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
00568 
00569   /* These fields record data obtained from optional markers recognized by
00570    * the JPEG library.
00571    */
00572   boolean saw_JFIF_marker;  /* TRUE iff a JFIF APP0 marker was found */
00573   /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
00574   UINT8 JFIF_major_version; /* JFIF version number */
00575   UINT8 JFIF_minor_version;
00576   UINT8 density_unit;              /* JFIF code for pixel size units */
00577   UINT16 X_density;         /* Horizontal pixel density */
00578   UINT16 Y_density;         /* Vertical pixel density */
00579   boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
00580   UINT8 Adobe_transform;    /* Color transform code from Adobe marker */
00581 
00582   boolean CCIR601_sampling; /* TRUE=first samples are cosited */
00583 
00584   /* Aside from the specific data retained from APPn markers known to the
00585    * library, the uninterpreted contents of any or all APPn and COM markers
00586    * can be saved in a list for examination by the application.
00587    */
00588   jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
00589 
00590   /* Remaining fields are known throughout decompressor, but generally
00591    * should not be touched by a surrounding application.
00592    */
00593 
00594   /*
00595    * These fields are computed during decompression startup
00596    */
00597   int max_h_samp_factor;    /* largest h_samp_factor */
00598   int max_v_samp_factor;    /* largest v_samp_factor */
00599 
00600   int min_DCT_scaled_size;  /* smallest DCT_scaled_size of any component */
00601 
00602   JDIMENSION total_iMCU_rows;      /* # of iMCU rows in image */
00603   /* The coefficient controller's input and output progress is measured in
00604    * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows
00605    * in fully interleaved JPEG scans, but are used whether the scan is
00606    * interleaved or not.  We define an iMCU row as v_samp_factor DCT block
00607    * rows of each component.  Therefore, the IDCT output contains
00608    * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.
00609    */
00610 
00611   JSAMPLE * sample_range_limit; /* table for fast range-limiting */
00612 
00613   /*
00614    * These fields are valid during any one scan.
00615    * They describe the components and MCUs actually appearing in the scan.
00616    * Note that the decompressor output side must not use these fields.
00617    */
00618   int comps_in_scan;        /* # of JPEG components in this scan */
00619   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
00620   /* *cur_comp_info[i] describes component that appears i'th in SOS */
00621 
00622   JDIMENSION MCUs_per_row;  /* # of MCUs across the image */
00623   JDIMENSION MCU_rows_in_scan;     /* # of MCU rows in the image */
00624 
00625   int blocks_in_MCU;        /* # of DCT blocks per MCU */
00626   int MCU_membership[D_MAX_BLOCKS_IN_MCU];
00627   /* MCU_membership[i] is index in cur_comp_info of component owning */
00628   /* i'th block in an MCU */
00629 
00630   int Ss, Se, Ah, Al;              /* progressive JPEG parameters for scan */
00631 
00632   /* This field is shared between entropy decoder and marker parser.
00633    * It is either zero or the code of a JPEG marker that has been
00634    * read from the data source, but has not yet been processed.
00635    */
00636   int unread_marker;
00637 
00638   /*
00639    * Links to decompression subobjects (methods, private variables of modules)
00640    */
00641   struct jpeg_decomp_master * master;
00642   struct jpeg_d_main_controller * main;
00643   struct jpeg_d_coef_controller * coef;
00644   struct jpeg_d_post_controller * post;
00645   struct jpeg_input_controller * inputctl;
00646   struct jpeg_marker_reader * marker;
00647   struct jpeg_entropy_decoder * entropy;
00648   struct jpeg_inverse_dct * idct;
00649   struct jpeg_upsampler * upsample;
00650   struct jpeg_color_deconverter * cconvert;
00651   struct jpeg_color_quantizer * cquantize;
00652 };
00653 
00654 
00655 /* "Object" declarations for JPEG modules that may be supplied or called
00656  * directly by the surrounding application.
00657  * As with all objects in the JPEG library, these structs only define the
00658  * publicly visible methods and state variables of a module.  Additional
00659  * private fields may exist after the public ones.
00660  */
00661 
00662 
00663 /* Error handler object */
00664 
00665 struct jpeg_error_mgr {
00666   /* Error exit handler: does not return to caller */
00667   JMETHOD(void, error_exit, (j_common_ptr cinfo));
00668   /* Conditionally emit a trace or warning message */
00669   JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
00670   /* Routine that actually outputs a trace or error message */
00671   JMETHOD(void, output_message, (j_common_ptr cinfo));
00672   /* Format a message string for the most recent JPEG error or message */
00673   JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
00674 #define JMSG_LENGTH_MAX  200       /* recommended size of format_message buffer */
00675   /* Reset error state variables at start of a new image */
00676   JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
00677   
00678   /* The message ID code and any parameters are saved here.
00679    * A message can have one string parameter or up to 8 int parameters.
00680    */
00681   int msg_code;
00682 #define JMSG_STR_PARM_MAX  80
00683   union {
00684     int i[8];
00685     char s[JMSG_STR_PARM_MAX];
00686   } msg_parm;
00687   
00688   /* Standard state variables for error facility */
00689   
00690   int trace_level;          /* max msg_level that will be displayed */
00691   
00692   /* For recoverable corrupt-data errors, we emit a warning message,
00693    * but keep going unless emit_message chooses to abort.  emit_message
00694    * should count warnings in num_warnings.  The surrounding application
00695    * can check for bad data by seeing if num_warnings is nonzero at the
00696    * end of processing.
00697    */
00698   long num_warnings;        /* number of corrupt-data warnings */
00699 
00700   /* These fields point to the table(s) of error message strings.
00701    * An application can change the table pointer to switch to a different
00702    * message list (typically, to change the language in which errors are
00703    * reported).  Some applications may wish to add additional error codes
00704    * that will be handled by the JPEG library error mechanism; the second
00705    * table pointer is used for this purpose.
00706    *
00707    * First table includes all errors generated by JPEG library itself.
00708    * Error code 0 is reserved for a "no such error string" message.
00709    */
00710   const char * const * jpeg_message_table; /* Library errors */
00711   int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */
00712   /* Second table can be added by application (see cjpeg/djpeg for example).
00713    * It contains strings numbered first_addon_message..last_addon_message.
00714    */
00715   const char * const * addon_message_table; /* Non-library errors */
00716   int first_addon_message;  /* code for first string in addon table */
00717   int last_addon_message;   /* code for last string in addon table */
00718 };
00719 
00720 
00721 /* Progress monitor object */
00722 
00723 struct jpeg_progress_mgr {
00724   JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
00725 
00726   long pass_counter;        /* work units completed in this pass */
00727   long pass_limit;          /* total number of work units in this pass */
00728   int completed_passes;            /* passes completed so far */
00729   int total_passes;         /* total number of passes expected */
00730 };
00731 
00732 
00733 /* Data destination object for compression */
00734 
00735 struct jpeg_destination_mgr {
00736   JOCTET * next_output_byte;       /* => next byte to write in buffer */
00737   size_t free_in_buffer;    /* # of byte spaces remaining in buffer */
00738 
00739   JMETHOD(void, init_destination, (j_compress_ptr cinfo));
00740   JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
00741   JMETHOD(void, term_destination, (j_compress_ptr cinfo));
00742 };
00743 
00744 
00745 /* Data source object for decompression */
00746 
00747 struct jpeg_source_mgr {
00748   const JOCTET * next_input_byte; /* => next byte to read from buffer */
00749   size_t bytes_in_buffer;   /* # of bytes remaining in buffer */
00750 
00751   JMETHOD(void, init_source, (j_decompress_ptr cinfo));
00752   JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
00753   JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
00754   JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
00755   JMETHOD(void, term_source, (j_decompress_ptr cinfo));
00756 };
00757 
00758 
00759 /* Memory manager object.
00760  * Allocates "small" objects (a few K total), "large" objects (tens of K),
00761  * and "really big" objects (virtual arrays with backing store if needed).
00762  * The memory manager does not allow individual objects to be freed; rather,
00763  * each created object is assigned to a pool, and whole pools can be freed
00764  * at once.  This is faster and more convenient than remembering exactly what
00765  * to free, especially where malloc()/free() are not too speedy.
00766  * NB: alloc routines never return NULL.  They exit to error_exit if not
00767  * successful.
00768  */
00769 
00770 #define JPOOL_PERMANENT     0      /* lasts until master record is destroyed */
00771 #define JPOOL_IMAGE  1      /* lasts until done with image/datastream */
00772 #define JPOOL_NUMPOOLS      2
00773 
00774 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
00775 typedef struct jvirt_barray_control * jvirt_barray_ptr;
00776 
00777 
00778 struct jpeg_memory_mgr {
00779   /* Method pointers */
00780   JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
00781                             size_t sizeofobject));
00782   JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
00783                                  size_t sizeofobject));
00784   JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
00785                                  JDIMENSION samplesperrow,
00786                                  JDIMENSION numrows));
00787   JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
00788                                   JDIMENSION blocksperrow,
00789                                   JDIMENSION numrows));
00790   JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
00791                                             int pool_id,
00792                                             boolean pre_zero,
00793                                             JDIMENSION samplesperrow,
00794                                             JDIMENSION numrows,
00795                                             JDIMENSION maxaccess));
00796   JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
00797                                             int pool_id,
00798                                             boolean pre_zero,
00799                                             JDIMENSION blocksperrow,
00800                                             JDIMENSION numrows,
00801                                             JDIMENSION maxaccess));
00802   JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
00803   JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
00804                                       jvirt_sarray_ptr ptr,
00805                                       JDIMENSION start_row,
00806                                       JDIMENSION num_rows,
00807                                       boolean writable));
00808   JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
00809                                        jvirt_barray_ptr ptr,
00810                                        JDIMENSION start_row,
00811                                        JDIMENSION num_rows,
00812                                        boolean writable));
00813   JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
00814   JMETHOD(void, self_destruct, (j_common_ptr cinfo));
00815 
00816   /* Limit on memory allocation for this JPEG object.  (Note that this is
00817    * merely advisory, not a guaranteed maximum; it only affects the space
00818    * used for virtual-array buffers.)  May be changed by outer application
00819    * after creating the JPEG object.
00820    */
00821   long max_memory_to_use;
00822 
00823   /* Maximum allocation request accepted by alloc_large. */
00824   long max_alloc_chunk;
00825 };
00826 
00827 
00828 /* Routine signature for application-supplied marker processing methods.
00829  * Need not pass marker code since it is stored in cinfo->unread_marker.
00830  */
00831 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
00832 
00833 
00834 /* Declarations for routines called by application.
00835  * The JPP macro hides prototype parameters from compilers that can't cope.
00836  * Note JPP requires double parentheses.
00837  */
00838 
00839 #ifdef HAVE_PROTOTYPES
00840 #define JPP(arglist) arglist
00841 #else
00842 #define JPP(arglist) ()
00843 #endif
00844 
00845 
00846 /* Short forms of external names for systems with brain-damaged linkers.
00847  * We shorten external names to be unique in the first six letters, which
00848  * is good enough for all known systems.
00849  * (If your compiler itself needs names to be unique in less than 15 
00850  * characters, you are out of luck.  Get a better compiler.)
00851  */
00852 
00853 #ifdef NEED_SHORT_EXTERNAL_NAMES
00854 #define jpeg_std_error             jStdError
00855 #define jpeg_CreateCompress jCreaCompress
00856 #define jpeg_CreateDecompress      jCreaDecompress
00857 #define jpeg_destroy_compress      jDestCompress
00858 #define jpeg_destroy_decompress    jDestDecompress
00859 #define jpeg_stdio_dest            jStdDest
00860 #define jpeg_stdio_src             jStdSrc
00861 #define jpeg_set_defaults   jSetDefaults
00862 #define jpeg_set_colorspace jSetColorspace
00863 #define jpeg_default_colorspace    jDefColorspace
00864 #define jpeg_set_quality    jSetQuality
00865 #define jpeg_set_linear_quality    jSetLQuality
00866 #define jpeg_add_quant_table       jAddQuantTable
00867 #define jpeg_quality_scaling       jQualityScaling
00868 #define jpeg_simple_progression    jSimProgress
00869 #define jpeg_suppress_tables       jSuppressTables
00870 #define jpeg_alloc_quant_table     jAlcQTable
00871 #define jpeg_alloc_huff_table      jAlcHTable
00872 #define jpeg_start_compress jStrtCompress
00873 #define jpeg_write_scanlines       jWrtScanlines
00874 #define jpeg_finish_compress       jFinCompress
00875 #define jpeg_write_raw_data jWrtRawData
00876 #define jpeg_write_marker   jWrtMarker
00877 #define jpeg_write_m_header jWrtMHeader
00878 #define jpeg_write_m_byte   jWrtMByte
00879 #define jpeg_write_tables   jWrtTables
00880 #define jpeg_read_header    jReadHeader
00881 #define jpeg_start_decompress      jStrtDecompress
00882 #define jpeg_read_scanlines jReadScanlines
00883 #define jpeg_finish_decompress     jFinDecompress
00884 #define jpeg_read_raw_data  jReadRawData
00885 #define jpeg_has_multiple_scans    jHasMultScn
00886 #define jpeg_start_output   jStrtOutput
00887 #define jpeg_finish_output  jFinOutput
00888 #define jpeg_input_complete jInComplete
00889 #define jpeg_new_colormap   jNewCMap
00890 #define jpeg_consume_input  jConsumeInput
00891 #define jpeg_calc_output_dimensions       jCalcDimensions
00892 #define jpeg_save_markers   jSaveMarkers
00893 #define jpeg_set_marker_processor  jSetMarker
00894 #define jpeg_read_coefficients     jReadCoefs
00895 #define jpeg_write_coefficients    jWrtCoefs
00896 #define jpeg_copy_critical_parameters     jCopyCrit
00897 #define jpeg_abort_compress jAbrtCompress
00898 #define jpeg_abort_decompress      jAbrtDecompress
00899 #define jpeg_abort          jAbort
00900 #define jpeg_destroy        jDestroy
00901 #define jpeg_resync_to_restart     jResyncRestart
00902 #endif /* NEED_SHORT_EXTERNAL_NAMES */
00903 
00904 #ifdef __cplusplus
00905 extern "C" {
00906 #endif
00907 
00908 /* Default error-management setup */
00909 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
00910        JPP((struct jpeg_error_mgr * err));
00911 
00912 /* Initialization of JPEG compression objects.
00913  * jpeg_create_compress() and jpeg_create_decompress() are the exported
00914  * names that applications should call.  These expand to calls on
00915  * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
00916  * passed for version mismatch checking.
00917  * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
00918  */
00919 #define jpeg_create_compress(cinfo) \
00920     jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
00921                      (size_t) sizeof(struct jpeg_compress_struct))
00922 #define jpeg_create_decompress(cinfo) \
00923     jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
00924                        (size_t) sizeof(struct jpeg_decompress_struct))
00925 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
00926                                   int version, size_t structsize));
00927 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
00928                                    int version, size_t structsize));
00929 /* Destruction of JPEG compression objects */
00930 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
00931 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
00932 
00933 /* Standard data source and destination managers: stdio streams. */
00934 /* Caller is responsible for opening the file before and closing after. */
00935 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
00936 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
00937 
00938 /* Default parameter setup for compression */
00939 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
00940 /* Compression parameter setup aids */
00941 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
00942                                   J_COLOR_SPACE colorspace));
00943 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
00944 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
00945                                boolean force_baseline));
00946 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
00947                                      int scale_factor,
00948                                      boolean force_baseline));
00949 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
00950                                    const unsigned int *basic_table,
00951                                    int scale_factor,
00952                                    boolean force_baseline));
00953 EXTERN(int) jpeg_quality_scaling JPP((int quality));
00954 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
00955 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
00956                                    boolean suppress));
00957 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
00958 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
00959 
00960 /* Main entry points for compression */
00961 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
00962                                   boolean write_all_tables));
00963 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
00964                                         JSAMPARRAY scanlines,
00965                                         JDIMENSION num_lines));
00966 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
00967 
00968 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
00969 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
00970                                        JSAMPIMAGE data,
00971                                        JDIMENSION num_lines));
00972 
00973 /* Write a special marker.  See libjpeg.doc concerning safe usage. */
00974 EXTERN(void) jpeg_write_marker
00975        JPP((j_compress_ptr cinfo, int marker,
00976             const JOCTET * dataptr, unsigned int datalen));
00977 /* Same, but piecemeal. */
00978 EXTERN(void) jpeg_write_m_header
00979        JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
00980 EXTERN(void) jpeg_write_m_byte
00981        JPP((j_compress_ptr cinfo, int val));
00982 
00983 /* Alternate compression function: just write an abbreviated table file */
00984 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
00985 
00986 /* Decompression startup: read start of JPEG datastream to see what's there */
00987 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
00988                               boolean require_image));
00989 /* Return value is one of: */
00990 #define JPEG_SUSPENDED             0 /* Suspended due to lack of input data */
00991 #define JPEG_HEADER_OK             1 /* Found valid image datastream */
00992 #define JPEG_HEADER_TABLES_ONLY    2 /* Found valid table-specs-only datastream */
00993 /* If you pass require_image = TRUE (normal case), you need not check for
00994  * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
00995  * JPEG_SUSPENDED is only possible if you use a data source module that can
00996  * give a suspension return (the stdio source module doesn't).
00997  */
00998 
00999 /* Main entry points for decompression */
01000 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
01001 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
01002                                        JSAMPARRAY scanlines,
01003                                        JDIMENSION max_lines));
01004 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
01005 
01006 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
01007 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
01008                                       JSAMPIMAGE data,
01009                                       JDIMENSION max_lines));
01010 
01011 /* Additional entry points for buffered-image mode. */
01012 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
01013 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
01014                                    int scan_number));
01015 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
01016 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
01017 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
01018 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
01019 /* Return value is one of: */
01020 /* #define JPEG_SUSPENDED   0    Suspended due to lack of input data */
01021 #define JPEG_REACHED_SOS    1 /* Reached start of new scan */
01022 #define JPEG_REACHED_EOI    2 /* Reached end of image */
01023 #define JPEG_ROW_COMPLETED  3 /* Completed one iMCU row */
01024 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
01025 
01026 /* Precalculate output dimensions for current decompression parameters. */
01027 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
01028 
01029 /* Control saving of COM and APPn markers into marker_list. */
01030 EXTERN(void) jpeg_save_markers
01031        JPP((j_decompress_ptr cinfo, int marker_code,
01032             unsigned int length_limit));
01033 
01034 /* Install a special processing method for COM or APPn markers. */
01035 EXTERN(void) jpeg_set_marker_processor
01036        JPP((j_decompress_ptr cinfo, int marker_code,
01037             jpeg_marker_parser_method routine));
01038 
01039 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
01040 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
01041 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
01042                                      jvirt_barray_ptr * coef_arrays));
01043 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
01044                                           j_compress_ptr dstinfo));
01045 
01046 /* If you choose to abort compression or decompression before completing
01047  * jpeg_finish_(de)compress, then you need to clean up to release memory,
01048  * temporary files, etc.  You can just call jpeg_destroy_(de)compress
01049  * if you're done with the JPEG object, but if you want to clean it up and
01050  * reuse it, call this:
01051  */
01052 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
01053 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
01054 
01055 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
01056  * flavor of JPEG object.  These may be more convenient in some places.
01057  */
01058 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
01059 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
01060 
01061 /* Default restart-marker-resync procedure for use by data source modules */
01062 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
01063                                        int desired));
01064 
01065 #ifdef __cplusplus
01066 } /* extern "C" */
01067 #endif /* __cplusplus */
01068 
01069 /* These marker codes are exported since applications and data source modules
01070  * are likely to want to use them.
01071  */
01072 
01073 #define JPEG_RST0    0xD0   /* RST0 marker code */
01074 #define JPEG_EOI     0xD9   /* EOI marker code */
01075 #define JPEG_APP0    0xE0   /* APP0 marker code */
01076 #define JPEG_COM     0xFE   /* COM marker code */
01077 
01078 
01079 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
01080  * for structure definitions that are never filled in, keep it quiet by
01081  * supplying dummy definitions for the various substructures.
01082  */
01083 
01084 #ifdef INCOMPLETE_TYPES_BROKEN
01085 #ifndef JPEG_INTERNALS             /* will be defined in jpegint.h */
01086 struct jvirt_sarray_control { long dummy; };
01087 struct jvirt_barray_control { long dummy; };
01088 struct jpeg_comp_master { long dummy; };
01089 struct jpeg_c_main_controller { long dummy; };
01090 struct jpeg_c_prep_controller { long dummy; };
01091 struct jpeg_c_coef_controller { long dummy; };
01092 struct jpeg_marker_writer { long dummy; };
01093 struct jpeg_color_converter { long dummy; };
01094 struct jpeg_downsampler { long dummy; };
01095 struct jpeg_forward_dct { long dummy; };
01096 struct jpeg_entropy_encoder { long dummy; };
01097 struct jpeg_decomp_master { long dummy; };
01098 struct jpeg_d_main_controller { long dummy; };
01099 struct jpeg_d_coef_controller { long dummy; };
01100 struct jpeg_d_post_controller { long dummy; };
01101 struct jpeg_input_controller { long dummy; };
01102 struct jpeg_marker_reader { long dummy; };
01103 struct jpeg_entropy_decoder { long dummy; };
01104 struct jpeg_inverse_dct { long dummy; };
01105 struct jpeg_upsampler { long dummy; };
01106 struct jpeg_color_deconverter { long dummy; };
01107 struct jpeg_color_quantizer { long dummy; };
01108 #endif /* JPEG_INTERNALS */
01109 #endif /* INCOMPLETE_TYPES_BROKEN */
01110 
01111 
01112 /*
01113  * The JPEG library modules define JPEG_INTERNALS before including this file.
01114  * The internal structure declarations are read only when that is true.
01115  * Applications using the library should not include jpegint.h, but may wish
01116  * to include jerror.h.
01117  */
01118 
01119 #ifdef JPEG_INTERNALS
01120 #include "jpegint.h"        /* fetch private declarations */
01121 #include "jerror.h"         /* fetch error codes too */
01122 #endif
01123 
01124 #endif /* JPEGLIB_H */