jpeglib.h

00001 /*
00002  * jpeglib.h
00003  *
00004  * Copyright (C) 1991-1998, Thomas G. Lane.
00005  * Modified 2002-2015 by Guido Vollbeding.
00006  * This file is part of the Independent JPEG Group's software.
00007  * For conditions of distribution and use, see the accompanying README file.
00008  *
00009  * This file defines the application interface for the JPEG library.
00010  * Most applications using the library need only include this file,
00011  * and perhaps jerror.h if they want to know the exact error codes.
00012  */
00013 
00014 #ifndef JPEGLIB_H
00015 #define JPEGLIB_H
00016 
00017 /*
00018  * First we include the configuration files that record how this
00019  * installation of the JPEG library is set up.  jconfig.h can be
00020  * generated automatically for many systems.  jmorecfg.h contains
00021  * manual configuration options that most people need not worry about.
00022  */
00023 
00024 #ifndef JCONFIG_INCLUDED    /* in case jinclude.h already did */
00025 #include "jconfig.h"        /* widely used configuration options */
00026 #endif
00027 #include "jmorecfg.h"       /* seldom changed options */
00028 
00029 
00030 #ifdef __cplusplus
00031 #ifndef DONT_USE_EXTERN_C
00032 extern "C" {
00033 #endif
00034 #endif
00035 
00036 /* Version IDs for the JPEG library.
00037  * Might be useful for tests like "#if JPEG_LIB_VERSION >= 90".
00038  */
00039 
00040 #define JPEG_LIB_VERSION        90  /* Compatibility version 9.0 */
00041 #define JPEG_LIB_VERSION_MAJOR  9
00042 #define JPEG_LIB_VERSION_MINOR  2
00043 
00044 
00045 /* Various constants determining the sizes of things.
00046  * All of these are specified by the JPEG standard,
00047  * so don't change them if you want to be compatible.
00048  */
00049 
00050 #define DCTSIZE         8   /* The basic DCT block is 8x8 coefficients */
00051 #define DCTSIZE2        64  /* DCTSIZE squared; # of elements in a block */
00052 #define NUM_QUANT_TBLS      4   /* Quantization tables are numbered 0..3 */
00053 #define NUM_HUFF_TBLS       4   /* Huffman tables are numbered 0..3 */
00054 #define NUM_ARITH_TBLS      16  /* Arith-coding tables are numbered 0..15 */
00055 #define MAX_COMPS_IN_SCAN   4   /* JPEG limit on # of components in one scan */
00056 #define MAX_SAMP_FACTOR     4   /* JPEG limit on sampling factors */
00057 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
00058  * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
00059  * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
00060  * to handle it.  We even let you do this from the jconfig.h file.  However,
00061  * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
00062  * sometimes emits noncompliant files doesn't mean you should too.
00063  */
00064 #define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
00065 #ifndef D_MAX_BLOCKS_IN_MCU
00066 #define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
00067 #endif
00068 
00069 
00070 /* Data structures for images (arrays of samples and of DCT coefficients).
00071  * On 80x86 machines, the image arrays are too big for near pointers,
00072  * but the pointer arrays can fit in near memory.
00073  */
00074 
00075 typedef JSAMPLE FAR *JSAMPROW;  /* ptr to one image row of pixel samples. */
00076 typedef JSAMPROW *JSAMPARRAY;   /* ptr to some rows (a 2-D sample array) */
00077 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
00078 
00079 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
00080 typedef JBLOCK FAR *JBLOCKROW;  /* pointer to one row of coefficient blocks */
00081 typedef JBLOCKROW *JBLOCKARRAY;     /* a 2-D array of coefficient blocks */
00082 typedef JBLOCKARRAY *JBLOCKIMAGE;   /* a 3-D array of coefficient blocks */
00083 
00084 typedef JCOEF FAR *JCOEFPTR;    /* useful in a couple of places */
00085 
00086 
00087 /* Types for JPEG compression parameters and working tables. */
00088 
00089 
00090 /* DCT coefficient quantization tables. */
00091 
00092 typedef struct {
00093   /* This array gives the coefficient quantizers in natural array order
00094    * (not the zigzag order in which they are stored in a JPEG DQT marker).
00095    * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
00096    */
00097   UINT16 quantval[DCTSIZE2];    /* quantization step for each coefficient */
00098   /* This field is used only during compression.  It's initialized FALSE when
00099    * the table is created, and set TRUE when it's been output to the file.
00100    * You could suppress output of a table by setting this to TRUE.
00101    * (See jpeg_suppress_tables for an example.)
00102    */
00103   boolean sent_table;       /* TRUE when table has been output */
00104 } JQUANT_TBL;
00105 
00106 
00107 /* Huffman coding tables. */
00108 
00109 typedef struct {
00110   /* These two fields directly represent the contents of a JPEG DHT marker */
00111   UINT8 bits[17];       /* bits[k] = # of symbols with codes of */
00112                 /* length k bits; bits[0] is unused */
00113   UINT8 huffval[256];       /* The symbols, in order of incr code length */
00114   /* This field is used only during compression.  It's initialized FALSE when
00115    * the table is created, and set TRUE when it's been output to the file.
00116    * You could suppress output of a table by setting this to TRUE.
00117    * (See jpeg_suppress_tables for an example.)
00118    */
00119   boolean sent_table;       /* TRUE when table has been output */
00120 } JHUFF_TBL;
00121 
00122 
00123 /* Basic info about one component (color channel). */
00124 
00125 typedef struct {
00126   /* These values are fixed over the whole image. */
00127   /* For compression, they must be supplied by parameter setup; */
00128   /* for decompression, they are read from the SOF marker. */
00129   int component_id;     /* identifier for this component (0..255) */
00130   int component_index;      /* its index in SOF or cinfo->comp_info[] */
00131   int h_samp_factor;        /* horizontal sampling factor (1..4) */
00132   int v_samp_factor;        /* vertical sampling factor (1..4) */
00133   int quant_tbl_no;     /* quantization table selector (0..3) */
00134   /* These values may vary between scans. */
00135   /* For compression, they must be supplied by parameter setup; */
00136   /* for decompression, they are read from the SOS marker. */
00137   /* The decompressor output side may not use these variables. */
00138   int dc_tbl_no;        /* DC entropy table selector (0..3) */
00139   int ac_tbl_no;        /* AC entropy table selector (0..3) */
00140   
00141   /* Remaining fields should be treated as private by applications. */
00142   
00143   /* These values are computed during compression or decompression startup: */
00144   /* Component's size in DCT blocks.
00145    * Any dummy blocks added to complete an MCU are not counted; therefore
00146    * these values do not depend on whether a scan is interleaved or not.
00147    */
00148   JDIMENSION width_in_blocks;
00149   JDIMENSION height_in_blocks;
00150   /* Size of a DCT block in samples,
00151    * reflecting any scaling we choose to apply during the DCT step.
00152    * Values from 1 to 16 are supported.
00153    * Note that different components may receive different DCT scalings.
00154    */
00155   int DCT_h_scaled_size;
00156   int DCT_v_scaled_size;
00157   /* The downsampled dimensions are the component's actual, unpadded number
00158    * of samples at the main buffer (preprocessing/compression interface);
00159    * DCT scaling is included, so
00160    * downsampled_width =
00161    *   ceil(image_width * Hi/Hmax * DCT_h_scaled_size/block_size)
00162    * and similarly for height.
00163    */
00164   JDIMENSION downsampled_width;  /* actual width in samples */
00165   JDIMENSION downsampled_height; /* actual height in samples */
00166   /* For decompression, in cases where some of the components will be
00167    * ignored (eg grayscale output from YCbCr image), we can skip most
00168    * computations for the unused components.
00169    * For compression, some of the components will need further quantization
00170    * scale by factor of 2 after DCT (eg BG_YCC output from normal RGB input).
00171    * The field is first set TRUE for decompression, FALSE for compression
00172    * in initial_setup, and then adapted in color conversion setup.
00173    */
00174   boolean component_needed;
00175 
00176   /* These values are computed before starting a scan of the component. */
00177   /* The decompressor output side may not use these variables. */
00178   int MCU_width;        /* number of blocks per MCU, horizontally */
00179   int MCU_height;       /* number of blocks per MCU, vertically */
00180   int MCU_blocks;       /* MCU_width * MCU_height */
00181   int MCU_sample_width; /* MCU width in samples: MCU_width * DCT_h_scaled_size */
00182   int last_col_width;       /* # of non-dummy blocks across in last MCU */
00183   int last_row_height;      /* # of non-dummy blocks down in last MCU */
00184 
00185   /* Saved quantization table for component; NULL if none yet saved.
00186    * See jdinput.c comments about the need for this information.
00187    * This field is currently used only for decompression.
00188    */
00189   JQUANT_TBL * quant_table;
00190 
00191   /* Private per-component storage for DCT or IDCT subsystem. */
00192   void * dct_table;
00193 } jpeg_component_info;
00194 
00195 
00196 /* The script for encoding a multiple-scan file is an array of these: */
00197 
00198 typedef struct {
00199   int comps_in_scan;        /* number of components encoded in this scan */
00200   int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
00201   int Ss, Se;           /* progressive JPEG spectral selection parms */
00202   int Ah, Al;           /* progressive JPEG successive approx. parms */
00203 } jpeg_scan_info;
00204 
00205 /* The decompressor can save APPn and COM markers in a list of these: */
00206 
00207 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
00208 
00209 struct jpeg_marker_struct {
00210   jpeg_saved_marker_ptr next;   /* next in list, or NULL */
00211   UINT8 marker;         /* marker code: JPEG_COM, or JPEG_APP0+n */
00212   unsigned int original_length; /* # bytes of data in the file */
00213   unsigned int data_length; /* # bytes of data saved at data[] */
00214   JOCTET FAR * data;        /* the data contained in the marker */
00215   /* the marker length word is not counted in data_length or original_length */
00216 };
00217 
00218 /* Known color spaces. */
00219 
00220 typedef enum {
00221     JCS_UNKNOWN,        /* error/unspecified */
00222     JCS_GRAYSCALE,      /* monochrome */
00223     JCS_RGB,        /* red/green/blue, standard RGB (sRGB) */
00224     JCS_YCbCr,      /* Y/Cb/Cr (also known as YUV), standard YCC */
00225     JCS_CMYK,       /* C/M/Y/K */
00226     JCS_YCCK,       /* Y/Cb/Cr/K */
00227     JCS_BG_RGB,     /* big gamut red/green/blue, bg-sRGB */
00228     JCS_BG_YCC      /* big gamut Y/Cb/Cr, bg-sYCC */
00229 } J_COLOR_SPACE;
00230 
00231 /* Supported color transforms. */
00232 
00233 typedef enum {
00234     JCT_NONE           = 0,
00235     JCT_SUBTRACT_GREEN = 1
00236 } J_COLOR_TRANSFORM;
00237 
00238 /* DCT/IDCT algorithm options. */
00239 
00240 typedef enum {
00241     JDCT_ISLOW,     /* slow but accurate integer algorithm */
00242     JDCT_IFAST,     /* faster, less accurate integer method */
00243     JDCT_FLOAT      /* floating-point: accurate, fast on fast HW */
00244 } J_DCT_METHOD;
00245 
00246 #ifndef JDCT_DEFAULT        /* may be overridden in jconfig.h */
00247 #define JDCT_DEFAULT  JDCT_ISLOW
00248 #endif
00249 #ifndef JDCT_FASTEST        /* may be overridden in jconfig.h */
00250 #define JDCT_FASTEST  JDCT_IFAST
00251 #endif
00252 
00253 /* Dithering options for decompression. */
00254 
00255 typedef enum {
00256     JDITHER_NONE,       /* no dithering */
00257     JDITHER_ORDERED,    /* simple ordered dither */
00258     JDITHER_FS      /* Floyd-Steinberg error diffusion dither */
00259 } J_DITHER_MODE;
00260 
00261 
00262 /* Common fields between JPEG compression and decompression master structs. */
00263 
00264 #define jpeg_common_fields \
00265   struct jpeg_error_mgr * err;  /* Error handler module */\
00266   struct jpeg_memory_mgr * mem; /* Memory manager module */\
00267   struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
00268   void * client_data;       /* Available for use by application */\
00269   boolean is_decompressor;  /* So common code can tell which is which */\
00270   int global_state      /* For checking call sequence validity */
00271 
00272 /* Routines that are to be used by both halves of the library are declared
00273  * to receive a pointer to this structure.  There are no actual instances of
00274  * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
00275  */
00276 struct jpeg_common_struct {
00277   jpeg_common_fields;       /* Fields common to both master struct types */
00278   /* Additional fields follow in an actual jpeg_compress_struct or
00279    * jpeg_decompress_struct.  All three structs must agree on these
00280    * initial fields!  (This would be a lot cleaner in C++.)
00281    */
00282 };
00283 
00284 typedef struct jpeg_common_struct * j_common_ptr;
00285 typedef struct jpeg_compress_struct * j_compress_ptr;
00286 typedef struct jpeg_decompress_struct * j_decompress_ptr;
00287 
00288 
00289 /* Master record for a compression instance */
00290 
00291 struct jpeg_compress_struct {
00292   jpeg_common_fields;       /* Fields shared with jpeg_decompress_struct */
00293 
00294   /* Destination for compressed data */
00295   struct jpeg_destination_mgr * dest;
00296 
00297   /* Description of source image --- these fields must be filled in by
00298    * outer application before starting compression.  in_color_space must
00299    * be correct before you can even call jpeg_set_defaults().
00300    */
00301 
00302   JDIMENSION image_width;   /* input image width */
00303   JDIMENSION image_height;  /* input image height */
00304   int input_components;     /* # of color components in input image */
00305   J_COLOR_SPACE in_color_space; /* colorspace of input image */
00306 
00307   double input_gamma;       /* image gamma of input image */
00308 
00309   /* Compression parameters --- these fields must be set before calling
00310    * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to
00311    * initialize everything to reasonable defaults, then changing anything
00312    * the application specifically wants to change.  That way you won't get
00313    * burnt when new parameters are added.  Also note that there are several
00314    * helper routines to simplify changing parameters.
00315    */
00316 
00317   unsigned int scale_num, scale_denom; /* fraction by which to scale image */
00318 
00319   JDIMENSION jpeg_width;    /* scaled JPEG image width */
00320   JDIMENSION jpeg_height;   /* scaled JPEG image height */
00321   /* Dimensions of actual JPEG image that will be written to file,
00322    * derived from input dimensions by scaling factors above.
00323    * These fields are computed by jpeg_start_compress().
00324    * You can also use jpeg_calc_jpeg_dimensions() to determine these values
00325    * in advance of calling jpeg_start_compress().
00326    */
00327 
00328   int data_precision;       /* bits of precision in image data */
00329 
00330   int num_components;       /* # of color components in JPEG image */
00331   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
00332 
00333   jpeg_component_info * comp_info;
00334   /* comp_info[i] describes component that appears i'th in SOF */
00335 
00336   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
00337   int q_scale_factor[NUM_QUANT_TBLS];
00338   /* ptrs to coefficient quantization tables, or NULL if not defined,
00339    * and corresponding scale factors (percentage, initialized 100).
00340    */
00341 
00342   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
00343   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
00344   /* ptrs to Huffman coding tables, or NULL if not defined */
00345 
00346   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
00347   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
00348   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
00349 
00350   int num_scans;        /* # of entries in scan_info array */
00351   const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
00352   /* The default value of scan_info is NULL, which causes a single-scan
00353    * sequential JPEG file to be emitted.  To create a multi-scan file,
00354    * set num_scans and scan_info to point to an array of scan definitions.
00355    */
00356 
00357   boolean raw_data_in;      /* TRUE=caller supplies downsampled data */
00358   boolean arith_code;       /* TRUE=arithmetic coding, FALSE=Huffman */
00359   boolean optimize_coding;  /* TRUE=optimize entropy encoding parms */
00360   boolean CCIR601_sampling; /* TRUE=first samples are cosited */
00361   boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */
00362   int smoothing_factor;     /* 1..100, or 0 for no input smoothing */
00363   J_DCT_METHOD dct_method;  /* DCT algorithm selector */
00364 
00365   /* The restart interval can be specified in absolute MCUs by setting
00366    * restart_interval, or in MCU rows by setting restart_in_rows
00367    * (in which case the correct restart_interval will be figured
00368    * for each scan).
00369    */
00370   unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
00371   int restart_in_rows;      /* if > 0, MCU rows per restart interval */
00372 
00373   /* Parameters controlling emission of special markers. */
00374 
00375   boolean write_JFIF_header;    /* should a JFIF marker be written? */
00376   UINT8 JFIF_major_version; /* What to write for the JFIF version number */
00377   UINT8 JFIF_minor_version;
00378   /* These three values are not used by the JPEG code, merely copied */
00379   /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */
00380   /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */
00381   /* ratio is defined by X_density/Y_density even when density_unit=0. */
00382   UINT8 density_unit;       /* JFIF code for pixel size units */
00383   UINT16 X_density;     /* Horizontal pixel density */
00384   UINT16 Y_density;     /* Vertical pixel density */
00385   boolean write_Adobe_marker;   /* should an Adobe marker be written? */
00386 
00387   J_COLOR_TRANSFORM color_transform;
00388   /* Color transform identifier, writes LSE marker if nonzero */
00389 
00390   /* State variable: index of next scanline to be written to
00391    * jpeg_write_scanlines().  Application may use this to control its
00392    * processing loop, e.g., "while (next_scanline < image_height)".
00393    */
00394 
00395   JDIMENSION next_scanline; /* 0 .. image_height-1  */
00396 
00397   /* Remaining fields are known throughout compressor, but generally
00398    * should not be touched by a surrounding application.
00399    */
00400 
00401   /*
00402    * These fields are computed during compression startup
00403    */
00404   boolean progressive_mode; /* TRUE if scan script uses progressive mode */
00405   int max_h_samp_factor;    /* largest h_samp_factor */
00406   int max_v_samp_factor;    /* largest v_samp_factor */
00407 
00408   int min_DCT_h_scaled_size;    /* smallest DCT_h_scaled_size of any component */
00409   int min_DCT_v_scaled_size;    /* smallest DCT_v_scaled_size of any component */
00410 
00411   JDIMENSION total_iMCU_rows;   /* # of iMCU rows to be input to coef ctlr */
00412   /* The coefficient controller receives data in units of MCU rows as defined
00413    * for fully interleaved scans (whether the JPEG file is interleaved or not).
00414    * There are v_samp_factor * DCTSIZE sample rows of each component in an
00415    * "iMCU" (interleaved MCU) row.
00416    */
00417   
00418   /*
00419    * These fields are valid during any one scan.
00420    * They describe the components and MCUs actually appearing in the scan.
00421    */
00422   int comps_in_scan;        /* # of JPEG components in this scan */
00423   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
00424   /* *cur_comp_info[i] describes component that appears i'th in SOS */
00425   
00426   JDIMENSION MCUs_per_row;  /* # of MCUs across the image */
00427   JDIMENSION MCU_rows_in_scan;  /* # of MCU rows in the image */
00428   
00429   int blocks_in_MCU;        /* # of DCT blocks per MCU */
00430   int MCU_membership[C_MAX_BLOCKS_IN_MCU];
00431   /* MCU_membership[i] is index in cur_comp_info of component owning */
00432   /* i'th block in an MCU */
00433 
00434   int Ss, Se, Ah, Al;       /* progressive JPEG parameters for scan */
00435 
00436   int block_size;       /* the basic DCT block size: 1..16 */
00437   const int * natural_order;    /* natural-order position array */
00438   int lim_Se;           /* min( Se, DCTSIZE2-1 ) */
00439 
00440   /*
00441    * Links to compression subobjects (methods and private variables of modules)
00442    */
00443   struct jpeg_comp_master * master;
00444   struct jpeg_c_main_controller * main;
00445   struct jpeg_c_prep_controller * prep;
00446   struct jpeg_c_coef_controller * coef;
00447   struct jpeg_marker_writer * marker;
00448   struct jpeg_color_converter * cconvert;
00449   struct jpeg_downsampler * downsample;
00450   struct jpeg_forward_dct * fdct;
00451   struct jpeg_entropy_encoder * entropy;
00452   jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
00453   int script_space_size;
00454 };
00455 
00456 
00457 /* Master record for a decompression instance */
00458 
00459 struct jpeg_decompress_struct {
00460   jpeg_common_fields;       /* Fields shared with jpeg_compress_struct */
00461 
00462   /* Source of compressed data */
00463   struct jpeg_source_mgr * src;
00464 
00465   /* Basic description of image --- filled in by jpeg_read_header(). */
00466   /* Application may inspect these values to decide how to process image. */
00467 
00468   JDIMENSION image_width;   /* nominal image width (from SOF marker) */
00469   JDIMENSION image_height;  /* nominal image height */
00470   int num_components;       /* # of color components in JPEG image */
00471   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
00472 
00473   /* Decompression processing parameters --- these fields must be set before
00474    * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes
00475    * them to default values.
00476    */
00477 
00478   J_COLOR_SPACE out_color_space; /* colorspace for output */
00479 
00480   unsigned int scale_num, scale_denom; /* fraction by which to scale image */
00481 
00482   double output_gamma;      /* image gamma wanted in output */
00483 
00484   boolean buffered_image;   /* TRUE=multiple output passes */
00485   boolean raw_data_out;     /* TRUE=downsampled data wanted */
00486 
00487   J_DCT_METHOD dct_method;  /* IDCT algorithm selector */
00488   boolean do_fancy_upsampling;  /* TRUE=apply fancy upsampling */
00489   boolean do_block_smoothing;   /* TRUE=apply interblock smoothing */
00490 
00491   boolean quantize_colors;  /* TRUE=colormapped output wanted */
00492   /* the following are ignored if not quantize_colors: */
00493   J_DITHER_MODE dither_mode;    /* type of color dithering to use */
00494   boolean two_pass_quantize;    /* TRUE=use two-pass color quantization */
00495   int desired_number_of_colors; /* max # colors to use in created colormap */
00496   /* these are significant only in buffered-image mode: */
00497   boolean enable_1pass_quant;   /* enable future use of 1-pass quantizer */
00498   boolean enable_external_quant;/* enable future use of external colormap */
00499   boolean enable_2pass_quant;   /* enable future use of 2-pass quantizer */
00500 
00501   /* Description of actual output image that will be returned to application.
00502    * These fields are computed by jpeg_start_decompress().
00503    * You can also use jpeg_calc_output_dimensions() to determine these values
00504    * in advance of calling jpeg_start_decompress().
00505    */
00506 
00507   JDIMENSION output_width;  /* scaled image width */
00508   JDIMENSION output_height; /* scaled image height */
00509   int out_color_components; /* # of color components in out_color_space */
00510   int output_components;    /* # of color components returned */
00511   /* output_components is 1 (a colormap index) when quantizing colors;
00512    * otherwise it equals out_color_components.
00513    */
00514   int rec_outbuf_height;    /* min recommended height of scanline buffer */
00515   /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
00516    * high, space and time will be wasted due to unnecessary data copying.
00517    * Usually rec_outbuf_height will be 1 or 2, at most 4.
00518    */
00519 
00520   /* When quantizing colors, the output colormap is described by these fields.
00521    * The application can supply a colormap by setting colormap non-NULL before
00522    * calling jpeg_start_decompress; otherwise a colormap is created during
00523    * jpeg_start_decompress or jpeg_start_output.
00524    * The map has out_color_components rows and actual_number_of_colors columns.
00525    */
00526   int actual_number_of_colors;  /* number of entries in use */
00527   JSAMPARRAY colormap;      /* The color map as a 2-D pixel array */
00528 
00529   /* State variables: these variables indicate the progress of decompression.
00530    * The application may examine these but must not modify them.
00531    */
00532 
00533   /* Row index of next scanline to be read from jpeg_read_scanlines().
00534    * Application may use this to control its processing loop, e.g.,
00535    * "while (output_scanline < output_height)".
00536    */
00537   JDIMENSION output_scanline;   /* 0 .. output_height-1  */
00538 
00539   /* Current input scan number and number of iMCU rows completed in scan.
00540    * These indicate the progress of the decompressor input side.
00541    */
00542   int input_scan_number;    /* Number of SOS markers seen so far */
00543   JDIMENSION input_iMCU_row;    /* Number of iMCU rows completed */
00544 
00545   /* The "output scan number" is the notional scan being displayed by the
00546    * output side.  The decompressor will not allow output scan/row number
00547    * to get ahead of input scan/row, but it can fall arbitrarily far behind.
00548    */
00549   int output_scan_number;   /* Nominal scan number being displayed */
00550   JDIMENSION output_iMCU_row;   /* Number of iMCU rows read */
00551 
00552   /* Current progression status.  coef_bits[c][i] indicates the precision
00553    * with which component c's DCT coefficient i (in zigzag order) is known.
00554    * It is -1 when no data has yet been received, otherwise it is the point
00555    * transform (shift) value for the most recent scan of the coefficient
00556    * (thus, 0 at completion of the progression).
00557    * This pointer is NULL when reading a non-progressive file.
00558    */
00559   int (*coef_bits)[DCTSIZE2];   /* -1 or current Al value for each coef */
00560 
00561   /* Internal JPEG parameters --- the application usually need not look at
00562    * these fields.  Note that the decompressor output side may not use
00563    * any parameters that can change between scans.
00564    */
00565 
00566   /* Quantization and Huffman tables are carried forward across input
00567    * datastreams when processing abbreviated JPEG datastreams.
00568    */
00569 
00570   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
00571   /* ptrs to coefficient quantization tables, or NULL if not defined */
00572 
00573   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
00574   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
00575   /* ptrs to Huffman coding tables, or NULL if not defined */
00576 
00577   /* These parameters are never carried across datastreams, since they
00578    * are given in SOF/SOS markers or defined to be reset by SOI.
00579    */
00580 
00581   int data_precision;       /* bits of precision in image data */
00582 
00583   jpeg_component_info * comp_info;
00584   /* comp_info[i] describes component that appears i'th in SOF */
00585 
00586   boolean is_baseline;      /* TRUE if Baseline SOF0 encountered */
00587   boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
00588   boolean arith_code;       /* TRUE=arithmetic coding, FALSE=Huffman */
00589 
00590   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
00591   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
00592   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
00593 
00594   unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
00595 
00596   /* These fields record data obtained from optional markers recognized by
00597    * the JPEG library.
00598    */
00599   boolean saw_JFIF_marker;  /* TRUE iff a JFIF APP0 marker was found */
00600   /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
00601   UINT8 JFIF_major_version; /* JFIF version number */
00602   UINT8 JFIF_minor_version;
00603   UINT8 density_unit;       /* JFIF code for pixel size units */
00604   UINT16 X_density;     /* Horizontal pixel density */
00605   UINT16 Y_density;     /* Vertical pixel density */
00606   boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
00607   UINT8 Adobe_transform;    /* Color transform code from Adobe marker */
00608 
00609   J_COLOR_TRANSFORM color_transform;
00610   /* Color transform identifier derived from LSE marker, otherwise zero */
00611 
00612   boolean CCIR601_sampling; /* TRUE=first samples are cosited */
00613 
00614   /* Aside from the specific data retained from APPn markers known to the
00615    * library, the uninterpreted contents of any or all APPn and COM markers
00616    * can be saved in a list for examination by the application.
00617    */
00618   jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
00619 
00620   /* Remaining fields are known throughout decompressor, but generally
00621    * should not be touched by a surrounding application.
00622    */
00623 
00624   /*
00625    * These fields are computed during decompression startup
00626    */
00627   int max_h_samp_factor;    /* largest h_samp_factor */
00628   int max_v_samp_factor;    /* largest v_samp_factor */
00629 
00630   int min_DCT_h_scaled_size;    /* smallest DCT_h_scaled_size of any component */
00631   int min_DCT_v_scaled_size;    /* smallest DCT_v_scaled_size of any component */
00632 
00633   JDIMENSION total_iMCU_rows;   /* # of iMCU rows in image */
00634   /* The coefficient controller's input and output progress is measured in
00635    * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows
00636    * in fully interleaved JPEG scans, but are used whether the scan is
00637    * interleaved or not.  We define an iMCU row as v_samp_factor DCT block
00638    * rows of each component.  Therefore, the IDCT output contains
00639    * v_samp_factor*DCT_v_scaled_size sample rows of a component per iMCU row.
00640    */
00641 
00642   JSAMPLE * sample_range_limit; /* table for fast range-limiting */
00643 
00644   /*
00645    * These fields are valid during any one scan.
00646    * They describe the components and MCUs actually appearing in the scan.
00647    * Note that the decompressor output side must not use these fields.
00648    */
00649   int comps_in_scan;        /* # of JPEG components in this scan */
00650   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
00651   /* *cur_comp_info[i] describes component that appears i'th in SOS */
00652 
00653   JDIMENSION MCUs_per_row;  /* # of MCUs across the image */
00654   JDIMENSION MCU_rows_in_scan;  /* # of MCU rows in the image */
00655 
00656   int blocks_in_MCU;        /* # of DCT blocks per MCU */
00657   int MCU_membership[D_MAX_BLOCKS_IN_MCU];
00658   /* MCU_membership[i] is index in cur_comp_info of component owning */
00659   /* i'th block in an MCU */
00660 
00661   int Ss, Se, Ah, Al;       /* progressive JPEG parameters for scan */
00662 
00663   /* These fields are derived from Se of first SOS marker.
00664    */
00665   int block_size;       /* the basic DCT block size: 1..16 */
00666   const int * natural_order; /* natural-order position array for entropy decode */
00667   int lim_Se;           /* min( Se, DCTSIZE2-1 ) for entropy decode */
00668 
00669   /* This field is shared between entropy decoder and marker parser.
00670    * It is either zero or the code of a JPEG marker that has been
00671    * read from the data source, but has not yet been processed.
00672    */
00673   int unread_marker;
00674 
00675   /*
00676    * Links to decompression subobjects (methods, private variables of modules)
00677    */
00678   struct jpeg_decomp_master * master;
00679   struct jpeg_d_main_controller * main;
00680   struct jpeg_d_coef_controller * coef;
00681   struct jpeg_d_post_controller * post;
00682   struct jpeg_input_controller * inputctl;
00683   struct jpeg_marker_reader * marker;
00684   struct jpeg_entropy_decoder * entropy;
00685   struct jpeg_inverse_dct * idct;
00686   struct jpeg_upsampler * upsample;
00687   struct jpeg_color_deconverter * cconvert;
00688   struct jpeg_color_quantizer * cquantize;
00689 };
00690 
00691 
00692 /* "Object" declarations for JPEG modules that may be supplied or called
00693  * directly by the surrounding application.
00694  * As with all objects in the JPEG library, these structs only define the
00695  * publicly visible methods and state variables of a module.  Additional
00696  * private fields may exist after the public ones.
00697  */
00698 
00699 
00700 /* Error handler object */
00701 
00702 struct jpeg_error_mgr {
00703   /* Error exit handler: does not return to caller */
00704   JMETHOD(noreturn_t, error_exit, (j_common_ptr cinfo));
00705   /* Conditionally emit a trace or warning message */
00706   JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
00707   /* Routine that actually outputs a trace or error message */
00708   JMETHOD(void, output_message, (j_common_ptr cinfo));
00709   /* Format a message string for the most recent JPEG error or message */
00710   JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
00711 #define JMSG_LENGTH_MAX  200    /* recommended size of format_message buffer */
00712   /* Reset error state variables at start of a new image */
00713   JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
00714   
00715   /* The message ID code and any parameters are saved here.
00716    * A message can have one string parameter or up to 8 int parameters.
00717    */
00718   int msg_code;
00719 #define JMSG_STR_PARM_MAX  80
00720   union {
00721     int i[8];
00722     char s[JMSG_STR_PARM_MAX];
00723   } msg_parm;
00724   
00725   /* Standard state variables for error facility */
00726   
00727   int trace_level;      /* max msg_level that will be displayed */
00728   
00729   /* For recoverable corrupt-data errors, we emit a warning message,
00730    * but keep going unless emit_message chooses to abort.  emit_message
00731    * should count warnings in num_warnings.  The surrounding application
00732    * can check for bad data by seeing if num_warnings is nonzero at the
00733    * end of processing.
00734    */
00735   long num_warnings;        /* number of corrupt-data warnings */
00736 
00737   /* These fields point to the table(s) of error message strings.
00738    * An application can change the table pointer to switch to a different
00739    * message list (typically, to change the language in which errors are
00740    * reported).  Some applications may wish to add additional error codes
00741    * that will be handled by the JPEG library error mechanism; the second
00742    * table pointer is used for this purpose.
00743    *
00744    * First table includes all errors generated by JPEG library itself.
00745    * Error code 0 is reserved for a "no such error string" message.
00746    */
00747   const char * const * jpeg_message_table; /* Library errors */
00748   int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */
00749   /* Second table can be added by application (see cjpeg/djpeg for example).
00750    * It contains strings numbered first_addon_message..last_addon_message.
00751    */
00752   const char * const * addon_message_table; /* Non-library errors */
00753   int first_addon_message;  /* code for first string in addon table */
00754   int last_addon_message;   /* code for last string in addon table */
00755 };
00756 
00757 
00758 /* Progress monitor object */
00759 
00760 struct jpeg_progress_mgr {
00761   JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
00762 
00763   long pass_counter;        /* work units completed in this pass */
00764   long pass_limit;      /* total number of work units in this pass */
00765   int completed_passes;     /* passes completed so far */
00766   int total_passes;     /* total number of passes expected */
00767 };
00768 
00769 
00770 /* Data destination object for compression */
00771 
00772 struct jpeg_destination_mgr {
00773   JOCTET * next_output_byte;    /* => next byte to write in buffer */
00774   size_t free_in_buffer;    /* # of byte spaces remaining in buffer */
00775 
00776   JMETHOD(void, init_destination, (j_compress_ptr cinfo));
00777   JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
00778   JMETHOD(void, term_destination, (j_compress_ptr cinfo));
00779 };
00780 
00781 
00782 /* Data source object for decompression */
00783 
00784 struct jpeg_source_mgr {
00785   const JOCTET * next_input_byte; /* => next byte to read from buffer */
00786   size_t bytes_in_buffer;   /* # of bytes remaining in buffer */
00787 
00788   JMETHOD(void, init_source, (j_decompress_ptr cinfo));
00789   JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
00790   JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
00791   JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
00792   JMETHOD(void, term_source, (j_decompress_ptr cinfo));
00793 };
00794 
00795 
00796 /* Memory manager object.
00797  * Allocates "small" objects (a few K total), "large" objects (tens of K),
00798  * and "really big" objects (virtual arrays with backing store if needed).
00799  * The memory manager does not allow individual objects to be freed; rather,
00800  * each created object is assigned to a pool, and whole pools can be freed
00801  * at once.  This is faster and more convenient than remembering exactly what
00802  * to free, especially where malloc()/free() are not too speedy.
00803  * NB: alloc routines never return NULL.  They exit to error_exit if not
00804  * successful.
00805  */
00806 
00807 #define JPOOL_PERMANENT 0   /* lasts until master record is destroyed */
00808 #define JPOOL_IMAGE 1   /* lasts until done with image/datastream */
00809 #define JPOOL_NUMPOOLS  2
00810 
00811 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
00812 typedef struct jvirt_barray_control * jvirt_barray_ptr;
00813 
00814 
00815 struct jpeg_memory_mgr {
00816   /* Method pointers */
00817   JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
00818                 size_t sizeofobject));
00819   JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
00820                      size_t sizeofobject));
00821   JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
00822                      JDIMENSION samplesperrow,
00823                      JDIMENSION numrows));
00824   JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
00825                       JDIMENSION blocksperrow,
00826                       JDIMENSION numrows));
00827   JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
00828                           int pool_id,
00829                           boolean pre_zero,
00830                           JDIMENSION samplesperrow,
00831                           JDIMENSION numrows,
00832                           JDIMENSION maxaccess));
00833   JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
00834                           int pool_id,
00835                           boolean pre_zero,
00836                           JDIMENSION blocksperrow,
00837                           JDIMENSION numrows,
00838                           JDIMENSION maxaccess));
00839   JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
00840   JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
00841                        jvirt_sarray_ptr ptr,
00842                        JDIMENSION start_row,
00843                        JDIMENSION num_rows,
00844                        boolean writable));
00845   JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
00846                         jvirt_barray_ptr ptr,
00847                         JDIMENSION start_row,
00848                         JDIMENSION num_rows,
00849                         boolean writable));
00850   JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
00851   JMETHOD(void, self_destruct, (j_common_ptr cinfo));
00852 
00853   /* Limit on memory allocation for this JPEG object.  (Note that this is
00854    * merely advisory, not a guaranteed maximum; it only affects the space
00855    * used for virtual-array buffers.)  May be changed by outer application
00856    * after creating the JPEG object.
00857    */
00858   long max_memory_to_use;
00859 
00860   /* Maximum allocation request accepted by alloc_large. */
00861   long max_alloc_chunk;
00862 };
00863 
00864 
00865 /* Routine signature for application-supplied marker processing methods.
00866  * Need not pass marker code since it is stored in cinfo->unread_marker.
00867  */
00868 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
00869 
00870 
00871 /* Declarations for routines called by application.
00872  * The JPP macro hides prototype parameters from compilers that can't cope.
00873  * Note JPP requires double parentheses.
00874  */
00875 
00876 #ifdef HAVE_PROTOTYPES
00877 #define JPP(arglist)    arglist
00878 #else
00879 #define JPP(arglist)    ()
00880 #endif
00881 
00882 
00883 /* Short forms of external names for systems with brain-damaged linkers.
00884  * We shorten external names to be unique in the first six letters, which
00885  * is good enough for all known systems.
00886  * (If your compiler itself needs names to be unique in less than 15 
00887  * characters, you are out of luck.  Get a better compiler.)
00888  */
00889 
00890 #ifdef NEED_SHORT_EXTERNAL_NAMES
00891 #define jpeg_std_error      jStdError
00892 #define jpeg_CreateCompress jCreaCompress
00893 #define jpeg_CreateDecompress   jCreaDecompress
00894 #define jpeg_destroy_compress   jDestCompress
00895 #define jpeg_destroy_decompress jDestDecompress
00896 #define jpeg_stdio_dest     jStdDest
00897 #define jpeg_stdio_src      jStdSrc
00898 #define jpeg_mem_dest       jMemDest
00899 #define jpeg_mem_src        jMemSrc
00900 #define jpeg_set_defaults   jSetDefaults
00901 #define jpeg_set_colorspace jSetColorspace
00902 #define jpeg_default_colorspace jDefColorspace
00903 #define jpeg_set_quality    jSetQuality
00904 #define jpeg_set_linear_quality jSetLQuality
00905 #define jpeg_default_qtables    jDefQTables
00906 #define jpeg_add_quant_table    jAddQuantTable
00907 #define jpeg_quality_scaling    jQualityScaling
00908 #define jpeg_simple_progression jSimProgress
00909 #define jpeg_suppress_tables    jSuppressTables
00910 #define jpeg_alloc_quant_table  jAlcQTable
00911 #define jpeg_alloc_huff_table   jAlcHTable
00912 #define jpeg_start_compress jStrtCompress
00913 #define jpeg_write_scanlines    jWrtScanlines
00914 #define jpeg_finish_compress    jFinCompress
00915 #define jpeg_calc_jpeg_dimensions   jCjpegDimensions
00916 #define jpeg_write_raw_data jWrtRawData
00917 #define jpeg_write_marker   jWrtMarker
00918 #define jpeg_write_m_header jWrtMHeader
00919 #define jpeg_write_m_byte   jWrtMByte
00920 #define jpeg_write_tables   jWrtTables
00921 #define jpeg_read_header    jReadHeader
00922 #define jpeg_start_decompress   jStrtDecompress
00923 #define jpeg_read_scanlines jReadScanlines
00924 #define jpeg_finish_decompress  jFinDecompress
00925 #define jpeg_read_raw_data  jReadRawData
00926 #define jpeg_has_multiple_scans jHasMultScn
00927 #define jpeg_start_output   jStrtOutput
00928 #define jpeg_finish_output  jFinOutput
00929 #define jpeg_input_complete jInComplete
00930 #define jpeg_new_colormap   jNewCMap
00931 #define jpeg_consume_input  jConsumeInput
00932 #define jpeg_core_output_dimensions jCoreDimensions
00933 #define jpeg_calc_output_dimensions jCalcDimensions
00934 #define jpeg_save_markers   jSaveMarkers
00935 #define jpeg_set_marker_processor   jSetMarker
00936 #define jpeg_read_coefficients  jReadCoefs
00937 #define jpeg_write_coefficients jWrtCoefs
00938 #define jpeg_copy_critical_parameters   jCopyCrit
00939 #define jpeg_abort_compress jAbrtCompress
00940 #define jpeg_abort_decompress   jAbrtDecompress
00941 #define jpeg_abort      jAbort
00942 #define jpeg_destroy        jDestroy
00943 #define jpeg_resync_to_restart  jResyncRestart
00944 #endif /* NEED_SHORT_EXTERNAL_NAMES */
00945 
00946 
00947 /* Default error-management setup */
00948 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
00949     JPP((struct jpeg_error_mgr * err));
00950 
00951 /* Initialization of JPEG compression objects.
00952  * jpeg_create_compress() and jpeg_create_decompress() are the exported
00953  * names that applications should call.  These expand to calls on
00954  * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
00955  * passed for version mismatch checking.
00956  * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
00957  */
00958 #define jpeg_create_compress(cinfo) \
00959     jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
00960             (size_t) sizeof(struct jpeg_compress_struct))
00961 #define jpeg_create_decompress(cinfo) \
00962     jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
00963               (size_t) sizeof(struct jpeg_decompress_struct))
00964 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
00965                       int version, size_t structsize));
00966 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
00967                     int version, size_t structsize));
00968 /* Destruction of JPEG compression objects */
00969 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
00970 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
00971 
00972 /* Standard data source and destination managers: stdio streams. */
00973 /* Caller is responsible for opening the file before and closing after. */
00974 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
00975 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
00976 
00977 /* Data source and destination managers: memory buffers. */
00978 EXTERN(void) jpeg_mem_dest JPP((j_compress_ptr cinfo,
00979                    unsigned char ** outbuffer,
00980                    unsigned long * outsize));
00981 EXTERN(void) jpeg_mem_src JPP((j_decompress_ptr cinfo,
00982                   const unsigned char * inbuffer,
00983                   unsigned long insize));
00984 
00985 /* Default parameter setup for compression */
00986 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
00987 /* Compression parameter setup aids */
00988 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
00989                       J_COLOR_SPACE colorspace));
00990 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
00991 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
00992                    boolean force_baseline));
00993 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
00994                       int scale_factor,
00995                       boolean force_baseline));
00996 EXTERN(void) jpeg_default_qtables JPP((j_compress_ptr cinfo,
00997                        boolean force_baseline));
00998 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
00999                        const unsigned int *basic_table,
01000                        int scale_factor,
01001                        boolean force_baseline));
01002 EXTERN(int) jpeg_quality_scaling JPP((int quality));
01003 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
01004 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
01005                        boolean suppress));
01006 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
01007 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
01008 
01009 /* Main entry points for compression */
01010 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
01011                       boolean write_all_tables));
01012 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
01013                          JSAMPARRAY scanlines,
01014                          JDIMENSION num_lines));
01015 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
01016 
01017 /* Precalculate JPEG dimensions for current compression parameters. */
01018 EXTERN(void) jpeg_calc_jpeg_dimensions JPP((j_compress_ptr cinfo));
01019 
01020 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
01021 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
01022                         JSAMPIMAGE data,
01023                         JDIMENSION num_lines));
01024 
01025 /* Write a special marker.  See libjpeg.txt concerning safe usage. */
01026 EXTERN(void) jpeg_write_marker
01027     JPP((j_compress_ptr cinfo, int marker,
01028          const JOCTET * dataptr, unsigned int datalen));
01029 /* Same, but piecemeal. */
01030 EXTERN(void) jpeg_write_m_header
01031     JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
01032 EXTERN(void) jpeg_write_m_byte
01033     JPP((j_compress_ptr cinfo, int val));
01034 
01035 /* Alternate compression function: just write an abbreviated table file */
01036 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
01037 
01038 /* Decompression startup: read start of JPEG datastream to see what's there */
01039 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
01040                   boolean require_image));
01041 /* Return value is one of: */
01042 #define JPEG_SUSPENDED      0 /* Suspended due to lack of input data */
01043 #define JPEG_HEADER_OK      1 /* Found valid image datastream */
01044 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
01045 /* If you pass require_image = TRUE (normal case), you need not check for
01046  * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
01047  * JPEG_SUSPENDED is only possible if you use a data source module that can
01048  * give a suspension return (the stdio source module doesn't).
01049  */
01050 
01051 /* Main entry points for decompression */
01052 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
01053 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
01054                         JSAMPARRAY scanlines,
01055                         JDIMENSION max_lines));
01056 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
01057 
01058 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
01059 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
01060                        JSAMPIMAGE data,
01061                        JDIMENSION max_lines));
01062 
01063 /* Additional entry points for buffered-image mode. */
01064 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
01065 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
01066                        int scan_number));
01067 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
01068 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
01069 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
01070 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
01071 /* Return value is one of: */
01072 /* #define JPEG_SUSPENDED   0    Suspended due to lack of input data */
01073 #define JPEG_REACHED_SOS    1 /* Reached start of new scan */
01074 #define JPEG_REACHED_EOI    2 /* Reached end of image */
01075 #define JPEG_ROW_COMPLETED  3 /* Completed one iMCU row */
01076 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
01077 
01078 /* Precalculate output dimensions for current decompression parameters. */
01079 EXTERN(void) jpeg_core_output_dimensions JPP((j_decompress_ptr cinfo));
01080 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
01081 
01082 /* Control saving of COM and APPn markers into marker_list. */
01083 EXTERN(void) jpeg_save_markers
01084     JPP((j_decompress_ptr cinfo, int marker_code,
01085          unsigned int length_limit));
01086 
01087 /* Install a special processing method for COM or APPn markers. */
01088 EXTERN(void) jpeg_set_marker_processor
01089     JPP((j_decompress_ptr cinfo, int marker_code,
01090          jpeg_marker_parser_method routine));
01091 
01092 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
01093 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
01094 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
01095                       jvirt_barray_ptr * coef_arrays));
01096 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
01097                         j_compress_ptr dstinfo));
01098 
01099 /* If you choose to abort compression or decompression before completing
01100  * jpeg_finish_(de)compress, then you need to clean up to release memory,
01101  * temporary files, etc.  You can just call jpeg_destroy_(de)compress
01102  * if you're done with the JPEG object, but if you want to clean it up and
01103  * reuse it, call this:
01104  */
01105 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
01106 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
01107 
01108 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
01109  * flavor of JPEG object.  These may be more convenient in some places.
01110  */
01111 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
01112 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
01113 
01114 /* Default restart-marker-resync procedure for use by data source modules */
01115 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
01116                         int desired));
01117 
01118 
01119 /* These marker codes are exported since applications and data source modules
01120  * are likely to want to use them.
01121  */
01122 
01123 #define JPEG_RST0   0xD0    /* RST0 marker code */
01124 #define JPEG_EOI    0xD9    /* EOI marker code */
01125 #define JPEG_APP0   0xE0    /* APP0 marker code */
01126 #define JPEG_COM    0xFE    /* COM marker code */
01127 
01128 
01129 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
01130  * for structure definitions that are never filled in, keep it quiet by
01131  * supplying dummy definitions for the various substructures.
01132  */
01133 
01134 #ifdef INCOMPLETE_TYPES_BROKEN
01135 #ifndef JPEG_INTERNALS      /* will be defined in jpegint.h */
01136 struct jvirt_sarray_control { long dummy; };
01137 struct jvirt_barray_control { long dummy; };
01138 struct jpeg_comp_master { long dummy; };
01139 struct jpeg_c_main_controller { long dummy; };
01140 struct jpeg_c_prep_controller { long dummy; };
01141 struct jpeg_c_coef_controller { long dummy; };
01142 struct jpeg_marker_writer { long dummy; };
01143 struct jpeg_color_converter { long dummy; };
01144 struct jpeg_downsampler { long dummy; };
01145 struct jpeg_forward_dct { long dummy; };
01146 struct jpeg_entropy_encoder { long dummy; };
01147 struct jpeg_decomp_master { long dummy; };
01148 struct jpeg_d_main_controller { long dummy; };
01149 struct jpeg_d_coef_controller { long dummy; };
01150 struct jpeg_d_post_controller { long dummy; };
01151 struct jpeg_input_controller { long dummy; };
01152 struct jpeg_marker_reader { long dummy; };
01153 struct jpeg_entropy_decoder { long dummy; };
01154 struct jpeg_inverse_dct { long dummy; };
01155 struct jpeg_upsampler { long dummy; };
01156 struct jpeg_color_deconverter { long dummy; };
01157 struct jpeg_color_quantizer { long dummy; };
01158 #endif /* JPEG_INTERNALS */
01159 #endif /* INCOMPLETE_TYPES_BROKEN */
01160 
01161 
01162 /*
01163  * The JPEG library modules define JPEG_INTERNALS before including this file.
01164  * The internal structure declarations are read only when that is true.
01165  * Applications using the library should not include jpegint.h, but may wish
01166  * to include jerror.h.
01167  */
01168 
01169 #ifdef JPEG_INTERNALS
01170 #include "jpegint.h"        /* fetch private declarations */
01171 #include "jerror.h"     /* fetch error codes too */
01172 #endif
01173 
01174 #ifdef __cplusplus
01175 #ifndef DONT_USE_EXTERN_C
01176 }
01177 #endif
01178 #endif
01179 
01180 #endif /* JPEGLIB_H */