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+/*
+ * jpeglib.h
+ *
+ * Copyright (C) 1991-1998, Thomas G. Lane.
+ * Modified 2002-2011 by Guido Vollbeding.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file defines the application interface for the JPEG library.
+ * Most applications using the library need only include this file,
+ * and perhaps jerror.h if they want to know the exact error codes.
+ */
+
+#ifndef JPEGLIB_H
+#define JPEGLIB_H
+
+/*
+ * First we include the configuration files that record how this
+ * installation of the JPEG library is set up. jconfig.h can be
+ * generated automatically for many systems. jmorecfg.h contains
+ * manual configuration options that most people need not worry about.
+ */
+
+#ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
+#include "jconfig.h" /* widely used configuration options */
+#endif
+#include "jmorecfg.h" /* seldom changed options */
+
+
+#ifdef __cplusplus
+#ifndef DONT_USE_EXTERN_C
+extern "C" {
+#endif
+#endif
+
+/* Version IDs for the JPEG library.
+ * Might be useful for tests like "#if JPEG_LIB_VERSION >= 80".
+ */
+
+#define JPEG_LIB_VERSION 80 /* Compatibility version 8.0 */
+#define JPEG_LIB_VERSION_MAJOR 8
+#define JPEG_LIB_VERSION_MINOR 4
+
+
+/* Various constants determining the sizes of things.
+ * All of these are specified by the JPEG standard, so don't change them
+ * if you want to be compatible.
+ */
+
+#define DCTSIZE 8 /* The basic DCT block is 8x8 coefficients */
+#define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
+#define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
+#define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
+#define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
+#define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
+#define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
+/* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
+ * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
+ * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
+ * to handle it. We even let you do this from the jconfig.h file. However,
+ * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
+ * sometimes emits noncompliant files doesn't mean you should too.
+ */
+#define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */
+#ifndef D_MAX_BLOCKS_IN_MCU
+#define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */
+#endif
+
+
+/* Data structures for images (arrays of samples and of DCT coefficients).
+ * On 80x86 machines, the image arrays are too big for near pointers,
+ * but the pointer arrays can fit in near memory.
+ */
+
+typedef JSAMPLE FAR *JSAMPROW; /* ptr to one image row of pixel samples. */
+typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */
+typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
+
+typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
+typedef JBLOCK FAR *JBLOCKROW; /* pointer to one row of coefficient blocks */
+typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */
+typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */
+
+typedef JCOEF FAR *JCOEFPTR; /* useful in a couple of places */
+
+
+/* Types for JPEG compression parameters and working tables. */
+
+
+/* DCT coefficient quantization tables. */
+
+typedef struct {
+ /* This array gives the coefficient quantizers in natural array order
+ * (not the zigzag order in which they are stored in a JPEG DQT marker).
+ * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
+ */
+ UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */
+ /* This field is used only during compression. It's initialized FALSE when
+ * the table is created, and set TRUE when it's been output to the file.
+ * You could suppress output of a table by setting this to TRUE.
+ * (See jpeg_suppress_tables for an example.)
+ */
+ boolean sent_table; /* TRUE when table has been output */
+} JQUANT_TBL;
+
+
+/* Huffman coding tables. */
+
+typedef struct {
+ /* These two fields directly represent the contents of a JPEG DHT marker */
+ UINT8 bits[17]; /* bits[k] = # of symbols with codes of */
+ /* length k bits; bits[0] is unused */
+ UINT8 huffval[256]; /* The symbols, in order of incr code length */
+ /* This field is used only during compression. It's initialized FALSE when
+ * the table is created, and set TRUE when it's been output to the file.
+ * You could suppress output of a table by setting this to TRUE.
+ * (See jpeg_suppress_tables for an example.)
+ */
+ boolean sent_table; /* TRUE when table has been output */
+} JHUFF_TBL;
+
+
+/* Basic info about one component (color channel). */
+
+typedef struct {
+ /* These values are fixed over the whole image. */
+ /* For compression, they must be supplied by parameter setup; */
+ /* for decompression, they are read from the SOF marker. */
+ int component_id; /* identifier for this component (0..255) */
+ int component_index; /* its index in SOF or cinfo->comp_info[] */
+ int h_samp_factor; /* horizontal sampling factor (1..4) */
+ int v_samp_factor; /* vertical sampling factor (1..4) */
+ int quant_tbl_no; /* quantization table selector (0..3) */
+ /* These values may vary between scans. */
+ /* For compression, they must be supplied by parameter setup; */
+ /* for decompression, they are read from the SOS marker. */
+ /* The decompressor output side may not use these variables. */
+ int dc_tbl_no; /* DC entropy table selector (0..3) */
+ int ac_tbl_no; /* AC entropy table selector (0..3) */
+
+ /* Remaining fields should be treated as private by applications. */
+
+ /* These values are computed during compression or decompression startup: */
+ /* Component's size in DCT blocks.
+ * Any dummy blocks added to complete an MCU are not counted; therefore
+ * these values do not depend on whether a scan is interleaved or not.
+ */
+ JDIMENSION width_in_blocks;
+ JDIMENSION height_in_blocks;
+ /* Size of a DCT block in samples,
+ * reflecting any scaling we choose to apply during the DCT step.
+ * Values from 1 to 16 are supported.
+ * Note that different components may receive different DCT scalings.
+ */
+ int DCT_h_scaled_size;
+ int DCT_v_scaled_size;
+ /* The downsampled dimensions are the component's actual, unpadded number
+ * of samples at the main buffer (preprocessing/compression interface);
+ * DCT scaling is included, so
+ * downsampled_width = ceil(image_width * Hi/Hmax * DCT_h_scaled_size/DCTSIZE)
+ * and similarly for height.
+ */
+ JDIMENSION downsampled_width; /* actual width in samples */
+ JDIMENSION downsampled_height; /* actual height in samples */
+ /* This flag is used only for decompression. In cases where some of the
+ * components will be ignored (eg grayscale output from YCbCr image),
+ * we can skip most computations for the unused components.
+ */
+ boolean component_needed; /* do we need the value of this component? */
+
+ /* These values are computed before starting a scan of the component. */
+ /* The decompressor output side may not use these variables. */
+ int MCU_width; /* number of blocks per MCU, horizontally */
+ int MCU_height; /* number of blocks per MCU, vertically */
+ int MCU_blocks; /* MCU_width * MCU_height */
+ int MCU_sample_width; /* MCU width in samples: MCU_width * DCT_h_scaled_size */
+ int last_col_width; /* # of non-dummy blocks across in last MCU */
+ int last_row_height; /* # of non-dummy blocks down in last MCU */
+
+ /* Saved quantization table for component; NULL if none yet saved.
+ * See jdinput.c comments about the need for this information.
+ * This field is currently used only for decompression.
+ */
+ JQUANT_TBL * quant_table;
+
+ /* Private per-component storage for DCT or IDCT subsystem. */
+ void * dct_table;
+} jpeg_component_info;
+
+
+/* The script for encoding a multiple-scan file is an array of these: */
+
+typedef struct {
+ int comps_in_scan; /* number of components encoded in this scan */
+ int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
+ int Ss, Se; /* progressive JPEG spectral selection parms */
+ int Ah, Al; /* progressive JPEG successive approx. parms */
+} jpeg_scan_info;
+
+/* The decompressor can save APPn and COM markers in a list of these: */
+
+typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
+
+struct jpeg_marker_struct {
+ jpeg_saved_marker_ptr next; /* next in list, or NULL */
+ UINT8 marker; /* marker code: JPEG_COM, or JPEG_APP0+n */
+ unsigned int original_length; /* # bytes of data in the file */
+ unsigned int data_length; /* # bytes of data saved at data[] */
+ JOCTET FAR * data; /* the data contained in the marker */
+ /* the marker length word is not counted in data_length or original_length */
+};
+
+/* Known color spaces. */
+
+typedef enum {
+ JCS_UNKNOWN, /* error/unspecified */
+ JCS_GRAYSCALE, /* monochrome */
+ JCS_RGB, /* red/green/blue */
+ JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */
+ JCS_CMYK, /* C/M/Y/K */
+ JCS_YCCK /* Y/Cb/Cr/K */
+} J_COLOR_SPACE;
+
+/* DCT/IDCT algorithm options. */
+
+typedef enum {
+ JDCT_ISLOW, /* slow but accurate integer algorithm */
+ JDCT_IFAST, /* faster, less accurate integer method */
+ JDCT_FLOAT /* floating-point: accurate, fast on fast HW */
+} J_DCT_METHOD;
+
+#ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */
+#define JDCT_DEFAULT JDCT_ISLOW
+#endif
+#ifndef JDCT_FASTEST /* may be overridden in jconfig.h */
+#define JDCT_FASTEST JDCT_IFAST
+#endif
+
+/* Dithering options for decompression. */
+
+typedef enum {
+ JDITHER_NONE, /* no dithering */
+ JDITHER_ORDERED, /* simple ordered dither */
+ JDITHER_FS /* Floyd-Steinberg error diffusion dither */
+} J_DITHER_MODE;
+
+
+/* Common fields between JPEG compression and decompression master structs. */
+
+#define jpeg_common_fields \
+ struct jpeg_error_mgr * err; /* Error handler module */\
+ struct jpeg_memory_mgr * mem; /* Memory manager module */\
+ struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
+ void * client_data; /* Available for use by application */\
+ boolean is_decompressor; /* So common code can tell which is which */\
+ int global_state /* For checking call sequence validity */
+
+/* Routines that are to be used by both halves of the library are declared
+ * to receive a pointer to this structure. There are no actual instances of
+ * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
+ */
+struct jpeg_common_struct {
+ jpeg_common_fields; /* Fields common to both master struct types */
+ /* Additional fields follow in an actual jpeg_compress_struct or
+ * jpeg_decompress_struct. All three structs must agree on these
+ * initial fields! (This would be a lot cleaner in C++.)
+ */
+};
+
+typedef struct jpeg_common_struct * j_common_ptr;
+typedef struct jpeg_compress_struct * j_compress_ptr;
+typedef struct jpeg_decompress_struct * j_decompress_ptr;
+
+
+/* Master record for a compression instance */
+
+struct jpeg_compress_struct {
+ jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */
+
+ /* Destination for compressed data */
+ struct jpeg_destination_mgr * dest;
+
+ /* Description of source image --- these fields must be filled in by
+ * outer application before starting compression. in_color_space must
+ * be correct before you can even call jpeg_set_defaults().
+ */
+
+ JDIMENSION image_width; /* input image width */
+ JDIMENSION image_height; /* input image height */
+ int input_components; /* # of color components in input image */
+ J_COLOR_SPACE in_color_space; /* colorspace of input image */
+
+ double input_gamma; /* image gamma of input image */
+
+ /* Compression parameters --- these fields must be set before calling
+ * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
+ * initialize everything to reasonable defaults, then changing anything
+ * the application specifically wants to change. That way you won't get
+ * burnt when new parameters are added. Also note that there are several
+ * helper routines to simplify changing parameters.
+ */
+
+ unsigned int scale_num, scale_denom; /* fraction by which to scale image */
+
+ JDIMENSION jpeg_width; /* scaled JPEG image width */
+ JDIMENSION jpeg_height; /* scaled JPEG image height */
+ /* Dimensions of actual JPEG image that will be written to file,
+ * derived from input dimensions by scaling factors above.
+ * These fields are computed by jpeg_start_compress().
+ * You can also use jpeg_calc_jpeg_dimensions() to determine these values
+ * in advance of calling jpeg_start_compress().
+ */
+
+ int data_precision; /* bits of precision in image data */
+
+ int num_components; /* # of color components in JPEG image */
+ J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
+
+ jpeg_component_info * comp_info;
+ /* comp_info[i] describes component that appears i'th in SOF */
+
+ JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
+ int q_scale_factor[NUM_QUANT_TBLS];
+ /* ptrs to coefficient quantization tables, or NULL if not defined,
+ * and corresponding scale factors (percentage, initialized 100).
+ */
+
+ JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
+ JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
+ /* ptrs to Huffman coding tables, or NULL if not defined */
+
+ UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
+ UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
+ UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
+
+ int num_scans; /* # of entries in scan_info array */
+ const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
+ /* The default value of scan_info is NULL, which causes a single-scan
+ * sequential JPEG file to be emitted. To create a multi-scan file,
+ * set num_scans and scan_info to point to an array of scan definitions.
+ */
+
+ boolean raw_data_in; /* TRUE=caller supplies downsampled data */
+ boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
+ boolean optimize_coding; /* TRUE=optimize entropy encoding parms */
+ boolean CCIR601_sampling; /* TRUE=first samples are cosited */
+ boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */
+ int smoothing_factor; /* 1..100, or 0 for no input smoothing */
+ J_DCT_METHOD dct_method; /* DCT algorithm selector */
+
+ /* The restart interval can be specified in absolute MCUs by setting
+ * restart_interval, or in MCU rows by setting restart_in_rows
+ * (in which case the correct restart_interval will be figured
+ * for each scan).
+ */
+ unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
+ int restart_in_rows; /* if > 0, MCU rows per restart interval */
+
+ /* Parameters controlling emission of special markers. */
+
+ boolean write_JFIF_header; /* should a JFIF marker be written? */
+ UINT8 JFIF_major_version; /* What to write for the JFIF version number */
+ UINT8 JFIF_minor_version;
+ /* These three values are not used by the JPEG code, merely copied */
+ /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */
+ /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */
+ /* ratio is defined by X_density/Y_density even when density_unit=0. */
+ UINT8 density_unit; /* JFIF code for pixel size units */
+ UINT16 X_density; /* Horizontal pixel density */
+ UINT16 Y_density; /* Vertical pixel density */
+ boolean write_Adobe_marker; /* should an Adobe marker be written? */
+
+ /* State variable: index of next scanline to be written to
+ * jpeg_write_scanlines(). Application may use this to control its
+ * processing loop, e.g., "while (next_scanline < image_height)".
+ */
+
+ JDIMENSION next_scanline; /* 0 .. image_height-1 */
+
+ /* Remaining fields are known throughout compressor, but generally
+ * should not be touched by a surrounding application.
+ */
+
+ /*
+ * These fields are computed during compression startup
+ */
+ boolean progressive_mode; /* TRUE if scan script uses progressive mode */
+ int max_h_samp_factor; /* largest h_samp_factor */
+ int max_v_samp_factor; /* largest v_samp_factor */
+
+ int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */
+ int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */
+
+ JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */
+ /* The coefficient controller receives data in units of MCU rows as defined
+ * for fully interleaved scans (whether the JPEG file is interleaved or not).
+ * There are v_samp_factor * DCTSIZE sample rows of each component in an
+ * "iMCU" (interleaved MCU) row.
+ */
+
+ /*
+ * These fields are valid during any one scan.
+ * They describe the components and MCUs actually appearing in the scan.
+ */
+ int comps_in_scan; /* # of JPEG components in this scan */
+ jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
+ /* *cur_comp_info[i] describes component that appears i'th in SOS */
+
+ JDIMENSION MCUs_per_row; /* # of MCUs across the image */
+ JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
+
+ int blocks_in_MCU; /* # of DCT blocks per MCU */
+ int MCU_membership[C_MAX_BLOCKS_IN_MCU];
+ /* MCU_membership[i] is index in cur_comp_info of component owning */
+ /* i'th block in an MCU */
+
+ int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
+
+ int block_size; /* the basic DCT block size: 1..16 */
+ const int * natural_order; /* natural-order position array */
+ int lim_Se; /* min( Se, DCTSIZE2-1 ) */
+
+ /*
+ * Links to compression subobjects (methods and private variables of modules)
+ */
+ struct jpeg_comp_master * master;
+ struct jpeg_c_main_controller * main;
+ struct jpeg_c_prep_controller * prep;
+ struct jpeg_c_coef_controller * coef;
+ struct jpeg_marker_writer * marker;
+ struct jpeg_color_converter * cconvert;
+ struct jpeg_downsampler * downsample;
+ struct jpeg_forward_dct * fdct;
+ struct jpeg_entropy_encoder * entropy;
+ jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
+ int script_space_size;
+};
+
+
+/* Master record for a decompression instance */
+
+struct jpeg_decompress_struct {
+ jpeg_common_fields; /* Fields shared with jpeg_compress_struct */
+
+ /* Source of compressed data */
+ struct jpeg_source_mgr * src;
+
+ /* Basic description of image --- filled in by jpeg_read_header(). */
+ /* Application may inspect these values to decide how to process image. */
+
+ JDIMENSION image_width; /* nominal image width (from SOF marker) */
+ JDIMENSION image_height; /* nominal image height */
+ int num_components; /* # of color components in JPEG image */
+ J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
+
+ /* Decompression processing parameters --- these fields must be set before
+ * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes
+ * them to default values.
+ */
+
+ J_COLOR_SPACE out_color_space; /* colorspace for output */
+
+ unsigned int scale_num, scale_denom; /* fraction by which to scale image */
+
+ double output_gamma; /* image gamma wanted in output */
+
+ boolean buffered_image; /* TRUE=multiple output passes */
+ boolean raw_data_out; /* TRUE=downsampled data wanted */
+
+ J_DCT_METHOD dct_method; /* IDCT algorithm selector */
+ boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */
+ boolean do_block_smoothing; /* TRUE=apply interblock smoothing */
+
+ boolean quantize_colors; /* TRUE=colormapped output wanted */
+ /* the following are ignored if not quantize_colors: */
+ J_DITHER_MODE dither_mode; /* type of color dithering to use */
+ boolean two_pass_quantize; /* TRUE=use two-pass color quantization */
+ int desired_number_of_colors; /* max # colors to use in created colormap */
+ /* these are significant only in buffered-image mode: */
+ boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */
+ boolean enable_external_quant;/* enable future use of external colormap */
+ boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */
+
+ /* Description of actual output image that will be returned to application.
+ * These fields are computed by jpeg_start_decompress().
+ * You can also use jpeg_calc_output_dimensions() to determine these values
+ * in advance of calling jpeg_start_decompress().
+ */
+
+ JDIMENSION output_width; /* scaled image width */
+ JDIMENSION output_height; /* scaled image height */
+ int out_color_components; /* # of color components in out_color_space */
+ int output_components; /* # of color components returned */
+ /* output_components is 1 (a colormap index) when quantizing colors;
+ * otherwise it equals out_color_components.
+ */
+ int rec_outbuf_height; /* min recommended height of scanline buffer */
+ /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
+ * high, space and time will be wasted due to unnecessary data copying.
+ * Usually rec_outbuf_height will be 1 or 2, at most 4.
+ */
+
+ /* When quantizing colors, the output colormap is described by these fields.
+ * The application can supply a colormap by setting colormap non-NULL before
+ * calling jpeg_start_decompress; otherwise a colormap is created during
+ * jpeg_start_decompress or jpeg_start_output.
+ * The map has out_color_components rows and actual_number_of_colors columns.
+ */
+ int actual_number_of_colors; /* number of entries in use */
+ JSAMPARRAY colormap; /* The color map as a 2-D pixel array */
+
+ /* State variables: these variables indicate the progress of decompression.
+ * The application may examine these but must not modify them.
+ */
+
+ /* Row index of next scanline to be read from jpeg_read_scanlines().
+ * Application may use this to control its processing loop, e.g.,
+ * "while (output_scanline < output_height)".
+ */
+ JDIMENSION output_scanline; /* 0 .. output_height-1 */
+
+ /* Current input scan number and number of iMCU rows completed in scan.
+ * These indicate the progress of the decompressor input side.
+ */
+ int input_scan_number; /* Number of SOS markers seen so far */
+ JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */
+
+ /* The "output scan number" is the notional scan being displayed by the
+ * output side. The decompressor will not allow output scan/row number
+ * to get ahead of input scan/row, but it can fall arbitrarily far behind.
+ */
+ int output_scan_number; /* Nominal scan number being displayed */
+ JDIMENSION output_iMCU_row; /* Number of iMCU rows read */
+
+ /* Current progression status. coef_bits[c][i] indicates the precision
+ * with which component c's DCT coefficient i (in zigzag order) is known.
+ * It is -1 when no data has yet been received, otherwise it is the point
+ * transform (shift) value for the most recent scan of the coefficient
+ * (thus, 0 at completion of the progression).
+ * This pointer is NULL when reading a non-progressive file.
+ */
+ int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */
+
+ /* Internal JPEG parameters --- the application usually need not look at
+ * these fields. Note that the decompressor output side may not use
+ * any parameters that can change between scans.
+ */
+
+ /* Quantization and Huffman tables are carried forward across input
+ * datastreams when processing abbreviated JPEG datastreams.
+ */
+
+ JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
+ /* ptrs to coefficient quantization tables, or NULL if not defined */
+
+ JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
+ JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
+ /* ptrs to Huffman coding tables, or NULL if not defined */
+
+ /* These parameters are never carried across datastreams, since they
+ * are given in SOF/SOS markers or defined to be reset by SOI.
+ */
+
+ int data_precision; /* bits of precision in image data */
+
+ jpeg_component_info * comp_info;
+ /* comp_info[i] describes component that appears i'th in SOF */
+
+ boolean is_baseline; /* TRUE if Baseline SOF0 encountered */
+ boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
+ boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
+
+ UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
+ UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
+ UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
+
+ unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
+
+ /* These fields record data obtained from optional markers recognized by
+ * the JPEG library.
+ */
+ boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */
+ /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
+ UINT8 JFIF_major_version; /* JFIF version number */
+ UINT8 JFIF_minor_version;
+ UINT8 density_unit; /* JFIF code for pixel size units */
+ UINT16 X_density; /* Horizontal pixel density */
+ UINT16 Y_density; /* Vertical pixel density */
+ boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
+ UINT8 Adobe_transform; /* Color transform code from Adobe marker */
+
+ boolean CCIR601_sampling; /* TRUE=first samples are cosited */
+
+ /* Aside from the specific data retained from APPn markers known to the
+ * library, the uninterpreted contents of any or all APPn and COM markers
+ * can be saved in a list for examination by the application.
+ */
+ jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
+
+ /* Remaining fields are known throughout decompressor, but generally
+ * should not be touched by a surrounding application.
+ */
+
+ /*
+ * These fields are computed during decompression startup
+ */
+ int max_h_samp_factor; /* largest h_samp_factor */
+ int max_v_samp_factor; /* largest v_samp_factor */
+
+ int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */
+ int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */
+
+ JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */
+ /* The coefficient controller's input and output progress is measured in
+ * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows
+ * in fully interleaved JPEG scans, but are used whether the scan is
+ * interleaved or not. We define an iMCU row as v_samp_factor DCT block
+ * rows of each component. Therefore, the IDCT output contains
+ * v_samp_factor*DCT_v_scaled_size sample rows of a component per iMCU row.
+ */
+
+ JSAMPLE * sample_range_limit; /* table for fast range-limiting */
+
+ /*
+ * These fields are valid during any one scan.
+ * They describe the components and MCUs actually appearing in the scan.
+ * Note that the decompressor output side must not use these fields.
+ */
+ int comps_in_scan; /* # of JPEG components in this scan */
+ jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
+ /* *cur_comp_info[i] describes component that appears i'th in SOS */
+
+ JDIMENSION MCUs_per_row; /* # of MCUs across the image */
+ JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
+
+ int blocks_in_MCU; /* # of DCT blocks per MCU */
+ int MCU_membership[D_MAX_BLOCKS_IN_MCU];
+ /* MCU_membership[i] is index in cur_comp_info of component owning */
+ /* i'th block in an MCU */
+
+ int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
+
+ /* These fields are derived from Se of first SOS marker.
+ */
+ int block_size; /* the basic DCT block size: 1..16 */
+ const int * natural_order; /* natural-order position array for entropy decode */
+ int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */
+
+ /* This field is shared between entropy decoder and marker parser.
+ * It is either zero or the code of a JPEG marker that has been
+ * read from the data source, but has not yet been processed.
+ */
+ int unread_marker;
+
+ /*
+ * Links to decompression subobjects (methods, private variables of modules)
+ */
+ struct jpeg_decomp_master * master;
+ struct jpeg_d_main_controller * main;
+ struct jpeg_d_coef_controller * coef;
+ struct jpeg_d_post_controller * post;
+ struct jpeg_input_controller * inputctl;
+ struct jpeg_marker_reader * marker;
+ struct jpeg_entropy_decoder * entropy;
+ struct jpeg_inverse_dct * idct;
+ struct jpeg_upsampler * upsample;
+ struct jpeg_color_deconverter * cconvert;
+ struct jpeg_color_quantizer * cquantize;
+};
+
+
+/* "Object" declarations for JPEG modules that may be supplied or called
+ * directly by the surrounding application.
+ * As with all objects in the JPEG library, these structs only define the
+ * publicly visible methods and state variables of a module. Additional
+ * private fields may exist after the public ones.
+ */
+
+
+/* Error handler object */
+
+struct jpeg_error_mgr {
+ /* Error exit handler: does not return to caller */
+ JMETHOD(void, error_exit, (j_common_ptr cinfo));
+ /* Conditionally emit a trace or warning message */
+ JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
+ /* Routine that actually outputs a trace or error message */
+ JMETHOD(void, output_message, (j_common_ptr cinfo));
+ /* Format a message string for the most recent JPEG error or message */
+ JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
+#define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */
+ /* Reset error state variables at start of a new image */
+ JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
+
+ /* The message ID code and any parameters are saved here.
+ * A message can have one string parameter or up to 8 int parameters.
+ */
+ int msg_code;
+#define JMSG_STR_PARM_MAX 80
+ union {
+ int i[8];
+ char s[JMSG_STR_PARM_MAX];
+ } msg_parm;
+
+ /* Standard state variables for error facility */
+
+ int trace_level; /* max msg_level that will be displayed */
+
+ /* For recoverable corrupt-data errors, we emit a warning message,
+ * but keep going unless emit_message chooses to abort. emit_message
+ * should count warnings in num_warnings. The surrounding application
+ * can check for bad data by seeing if num_warnings is nonzero at the
+ * end of processing.
+ */
+ long num_warnings; /* number of corrupt-data warnings */
+
+ /* These fields point to the table(s) of error message strings.
+ * An application can change the table pointer to switch to a different
+ * message list (typically, to change the language in which errors are
+ * reported). Some applications may wish to add additional error codes
+ * that will be handled by the JPEG library error mechanism; the second
+ * table pointer is used for this purpose.
+ *
+ * First table includes all errors generated by JPEG library itself.
+ * Error code 0 is reserved for a "no such error string" message.
+ */
+ const char * const * jpeg_message_table; /* Library errors */
+ int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */
+ /* Second table can be added by application (see cjpeg/djpeg for example).
+ * It contains strings numbered first_addon_message..last_addon_message.
+ */
+ const char * const * addon_message_table; /* Non-library errors */
+ int first_addon_message; /* code for first string in addon table */
+ int last_addon_message; /* code for last string in addon table */
+};
+
+
+/* Progress monitor object */
+
+struct jpeg_progress_mgr {
+ JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
+
+ long pass_counter; /* work units completed in this pass */
+ long pass_limit; /* total number of work units in this pass */
+ int completed_passes; /* passes completed so far */
+ int total_passes; /* total number of passes expected */
+};
+
+
+/* Data destination object for compression */
+
+struct jpeg_destination_mgr {
+ JOCTET * next_output_byte; /* => next byte to write in buffer */
+ size_t free_in_buffer; /* # of byte spaces remaining in buffer */
+
+ JMETHOD(void, init_destination, (j_compress_ptr cinfo));
+ JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
+ JMETHOD(void, term_destination, (j_compress_ptr cinfo));
+};
+
+
+/* Data source object for decompression */
+
+struct jpeg_source_mgr {
+ const JOCTET * next_input_byte; /* => next byte to read from buffer */
+ size_t bytes_in_buffer; /* # of bytes remaining in buffer */
+
+ JMETHOD(void, init_source, (j_decompress_ptr cinfo));
+ JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
+ JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
+ JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
+ JMETHOD(void, term_source, (j_decompress_ptr cinfo));
+};
+
+
+/* Memory manager object.
+ * Allocates "small" objects (a few K total), "large" objects (tens of K),
+ * and "really big" objects (virtual arrays with backing store if needed).
+ * The memory manager does not allow individual objects to be freed; rather,
+ * each created object is assigned to a pool, and whole pools can be freed
+ * at once. This is faster and more convenient than remembering exactly what
+ * to free, especially where malloc()/free() are not too speedy.
+ * NB: alloc routines never return NULL. They exit to error_exit if not
+ * successful.
+ */
+
+#define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */
+#define JPOOL_IMAGE 1 /* lasts until done with image/datastream */
+#define JPOOL_NUMPOOLS 2
+
+typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
+typedef struct jvirt_barray_control * jvirt_barray_ptr;
+
+
+struct jpeg_memory_mgr {
+ /* Method pointers */
+ JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
+ size_t sizeofobject));
+ JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
+ size_t sizeofobject));
+ JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
+ JDIMENSION samplesperrow,
+ JDIMENSION numrows));
+ JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
+ JDIMENSION blocksperrow,
+ JDIMENSION numrows));
+ JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
+ int pool_id,
+ boolean pre_zero,
+ JDIMENSION samplesperrow,
+ JDIMENSION numrows,
+ JDIMENSION maxaccess));
+ JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
+ int pool_id,
+ boolean pre_zero,
+ JDIMENSION blocksperrow,
+ JDIMENSION numrows,
+ JDIMENSION maxaccess));
+ JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
+ JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
+ jvirt_sarray_ptr ptr,
+ JDIMENSION start_row,
+ JDIMENSION num_rows,
+ boolean writable));
+ JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
+ jvirt_barray_ptr ptr,
+ JDIMENSION start_row,
+ JDIMENSION num_rows,
+ boolean writable));
+ JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
+ JMETHOD(void, self_destruct, (j_common_ptr cinfo));
+
+ /* Limit on memory allocation for this JPEG object. (Note that this is
+ * merely advisory, not a guaranteed maximum; it only affects the space
+ * used for virtual-array buffers.) May be changed by outer application
+ * after creating the JPEG object.
+ */
+ long max_memory_to_use;
+
+ /* Maximum allocation request accepted by alloc_large. */
+ long max_alloc_chunk;
+};
+
+
+/* Routine signature for application-supplied marker processing methods.
+ * Need not pass marker code since it is stored in cinfo->unread_marker.
+ */
+typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
+
+
+/* Declarations for routines called by application.
+ * The JPP macro hides prototype parameters from compilers that can't cope.
+ * Note JPP requires double parentheses.
+ */
+
+#ifdef HAVE_PROTOTYPES
+#define JPP(arglist) arglist
+#else
+#define JPP(arglist) ()
+#endif
+
+
+/* Short forms of external names for systems with brain-damaged linkers.
+ * We shorten external names to be unique in the first six letters, which
+ * is good enough for all known systems.
+ * (If your compiler itself needs names to be unique in less than 15
+ * characters, you are out of luck. Get a better compiler.)
+ */
+
+#ifdef NEED_SHORT_EXTERNAL_NAMES
+#define jpeg_std_error jStdError
+#define jpeg_CreateCompress jCreaCompress
+#define jpeg_CreateDecompress jCreaDecompress
+#define jpeg_destroy_compress jDestCompress
+#define jpeg_destroy_decompress jDestDecompress
+#define jpeg_stdio_dest jStdDest
+#define jpeg_stdio_src jStdSrc
+#define jpeg_mem_dest jMemDest
+#define jpeg_mem_src jMemSrc
+#define jpeg_set_defaults jSetDefaults
+#define jpeg_set_colorspace jSetColorspace
+#define jpeg_default_colorspace jDefColorspace
+#define jpeg_set_quality jSetQuality
+#define jpeg_set_linear_quality jSetLQuality
+#define jpeg_default_qtables jDefQTables
+#define jpeg_add_quant_table jAddQuantTable
+#define jpeg_quality_scaling jQualityScaling
+#define jpeg_simple_progression jSimProgress
+#define jpeg_suppress_tables jSuppressTables
+#define jpeg_alloc_quant_table jAlcQTable
+#define jpeg_alloc_huff_table jAlcHTable
+#define jpeg_start_compress jStrtCompress
+#define jpeg_write_scanlines jWrtScanlines
+#define jpeg_finish_compress jFinCompress
+#define jpeg_calc_jpeg_dimensions jCjpegDimensions
+#define jpeg_write_raw_data jWrtRawData
+#define jpeg_write_marker jWrtMarker
+#define jpeg_write_m_header jWrtMHeader
+#define jpeg_write_m_byte jWrtMByte
+#define jpeg_write_tables jWrtTables
+#define jpeg_read_header jReadHeader
+#define jpeg_start_decompress jStrtDecompress
+#define jpeg_read_scanlines jReadScanlines
+#define jpeg_finish_decompress jFinDecompress
+#define jpeg_read_raw_data jReadRawData
+#define jpeg_has_multiple_scans jHasMultScn
+#define jpeg_start_output jStrtOutput
+#define jpeg_finish_output jFinOutput
+#define jpeg_input_complete jInComplete
+#define jpeg_new_colormap jNewCMap
+#define jpeg_consume_input jConsumeInput
+#define jpeg_core_output_dimensions jCoreDimensions
+#define jpeg_calc_output_dimensions jCalcDimensions
+#define jpeg_save_markers jSaveMarkers
+#define jpeg_set_marker_processor jSetMarker
+#define jpeg_read_coefficients jReadCoefs
+#define jpeg_write_coefficients jWrtCoefs
+#define jpeg_copy_critical_parameters jCopyCrit
+#define jpeg_abort_compress jAbrtCompress
+#define jpeg_abort_decompress jAbrtDecompress
+#define jpeg_abort jAbort
+#define jpeg_destroy jDestroy
+#define jpeg_resync_to_restart jResyncRestart
+#endif /* NEED_SHORT_EXTERNAL_NAMES */
+
+
+/* Default error-management setup */
+EXTERN(struct jpeg_error_mgr *) jpeg_std_error
+ JPP((struct jpeg_error_mgr * err));
+
+/* Initialization of JPEG compression objects.
+ * jpeg_create_compress() and jpeg_create_decompress() are the exported
+ * names that applications should call. These expand to calls on
+ * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
+ * passed for version mismatch checking.
+ * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
+ */
+#define jpeg_create_compress(cinfo) \
+ jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
+ (size_t) sizeof(struct jpeg_compress_struct))
+#define jpeg_create_decompress(cinfo) \
+ jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
+ (size_t) sizeof(struct jpeg_decompress_struct))
+EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
+ int version, size_t structsize));
+EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
+ int version, size_t structsize));
+/* Destruction of JPEG compression objects */
+EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
+EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
+
+/* Standard data source and destination managers: stdio streams. */
+/* Caller is responsible for opening the file before and closing after. */
+EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
+EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
+
+/* Data source and destination managers: memory buffers. */
+EXTERN(void) jpeg_mem_dest JPP((j_compress_ptr cinfo,
+ unsigned char ** outbuffer,
+ unsigned long * outsize));
+EXTERN(void) jpeg_mem_src JPP((j_decompress_ptr cinfo,
+ unsigned char * inbuffer,
+ unsigned long insize));
+
+/* Default parameter setup for compression */
+EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
+/* Compression parameter setup aids */
+EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
+ J_COLOR_SPACE colorspace));
+EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
+EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
+ boolean force_baseline));
+EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
+ int scale_factor,
+ boolean force_baseline));
+EXTERN(void) jpeg_default_qtables JPP((j_compress_ptr cinfo,
+ boolean force_baseline));
+EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
+ const unsigned int *basic_table,
+ int scale_factor,
+ boolean force_baseline));
+EXTERN(int) jpeg_quality_scaling JPP((int quality));
+EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
+EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
+ boolean suppress));
+EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
+EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
+
+/* Main entry points for compression */
+EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
+ boolean write_all_tables));
+EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
+ JSAMPARRAY scanlines,
+ JDIMENSION num_lines));
+EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
+
+/* Precalculate JPEG dimensions for current compression parameters. */
+EXTERN(void) jpeg_calc_jpeg_dimensions JPP((j_compress_ptr cinfo));
+
+/* Replaces jpeg_write_scanlines when writing raw downsampled data. */
+EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
+ JSAMPIMAGE data,
+ JDIMENSION num_lines));
+
+/* Write a special marker. See libjpeg.txt concerning safe usage. */
+EXTERN(void) jpeg_write_marker
+ JPP((j_compress_ptr cinfo, int marker,
+ const JOCTET * dataptr, unsigned int datalen));
+/* Same, but piecemeal. */
+EXTERN(void) jpeg_write_m_header
+ JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
+EXTERN(void) jpeg_write_m_byte
+ JPP((j_compress_ptr cinfo, int val));
+
+/* Alternate compression function: just write an abbreviated table file */
+EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
+
+/* Decompression startup: read start of JPEG datastream to see what's there */
+EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
+ boolean require_image));
+/* Return value is one of: */
+#define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */
+#define JPEG_HEADER_OK 1 /* Found valid image datastream */
+#define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
+/* If you pass require_image = TRUE (normal case), you need not check for
+ * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
+ * JPEG_SUSPENDED is only possible if you use a data source module that can
+ * give a suspension return (the stdio source module doesn't).
+ */
+
+/* Main entry points for decompression */
+EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
+EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
+ JSAMPARRAY scanlines,
+ JDIMENSION max_lines));
+EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
+
+/* Replaces jpeg_read_scanlines when reading raw downsampled data. */
+EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
+ JSAMPIMAGE data,
+ JDIMENSION max_lines));
+
+/* Additional entry points for buffered-image mode. */
+EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
+EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
+ int scan_number));
+EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
+EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
+EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
+EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
+/* Return value is one of: */
+/* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */
+#define JPEG_REACHED_SOS 1 /* Reached start of new scan */
+#define JPEG_REACHED_EOI 2 /* Reached end of image */
+#define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */
+#define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
+
+/* Precalculate output dimensions for current decompression parameters. */
+EXTERN(void) jpeg_core_output_dimensions JPP((j_decompress_ptr cinfo));
+EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
+
+/* Control saving of COM and APPn markers into marker_list. */
+EXTERN(void) jpeg_save_markers
+ JPP((j_decompress_ptr cinfo, int marker_code,
+ unsigned int length_limit));
+
+/* Install a special processing method for COM or APPn markers. */
+EXTERN(void) jpeg_set_marker_processor
+ JPP((j_decompress_ptr cinfo, int marker_code,
+ jpeg_marker_parser_method routine));
+
+/* Read or write raw DCT coefficients --- useful for lossless transcoding. */
+EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
+EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
+ jvirt_barray_ptr * coef_arrays));
+EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
+ j_compress_ptr dstinfo));
+
+/* If you choose to abort compression or decompression before completing
+ * jpeg_finish_(de)compress, then you need to clean up to release memory,
+ * temporary files, etc. You can just call jpeg_destroy_(de)compress
+ * if you're done with the JPEG object, but if you want to clean it up and
+ * reuse it, call this:
+ */
+EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
+EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
+
+/* Generic versions of jpeg_abort and jpeg_destroy that work on either
+ * flavor of JPEG object. These may be more convenient in some places.
+ */
+EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
+EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
+
+/* Default restart-marker-resync procedure for use by data source modules */
+EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
+ int desired));
+
+
+/* These marker codes are exported since applications and data source modules
+ * are likely to want to use them.
+ */
+
+#define JPEG_RST0 0xD0 /* RST0 marker code */
+#define JPEG_EOI 0xD9 /* EOI marker code */
+#define JPEG_APP0 0xE0 /* APP0 marker code */
+#define JPEG_COM 0xFE /* COM marker code */
+
+
+/* If we have a brain-damaged compiler that emits warnings (or worse, errors)
+ * for structure definitions that are never filled in, keep it quiet by
+ * supplying dummy definitions for the various substructures.
+ */
+
+#ifdef INCOMPLETE_TYPES_BROKEN
+#ifndef JPEG_INTERNALS /* will be defined in jpegint.h */
+struct jvirt_sarray_control { long dummy; };
+struct jvirt_barray_control { long dummy; };
+struct jpeg_comp_master { long dummy; };
+struct jpeg_c_main_controller { long dummy; };
+struct jpeg_c_prep_controller { long dummy; };
+struct jpeg_c_coef_controller { long dummy; };
+struct jpeg_marker_writer { long dummy; };
+struct jpeg_color_converter { long dummy; };
+struct jpeg_downsampler { long dummy; };
+struct jpeg_forward_dct { long dummy; };
+struct jpeg_entropy_encoder { long dummy; };
+struct jpeg_decomp_master { long dummy; };
+struct jpeg_d_main_controller { long dummy; };
+struct jpeg_d_coef_controller { long dummy; };
+struct jpeg_d_post_controller { long dummy; };
+struct jpeg_input_controller { long dummy; };
+struct jpeg_marker_reader { long dummy; };
+struct jpeg_entropy_decoder { long dummy; };
+struct jpeg_inverse_dct { long dummy; };
+struct jpeg_upsampler { long dummy; };
+struct jpeg_color_deconverter { long dummy; };
+struct jpeg_color_quantizer { long dummy; };
+#endif /* JPEG_INTERNALS */
+#endif /* INCOMPLETE_TYPES_BROKEN */
+
+
+/*
+ * The JPEG library modules define JPEG_INTERNALS before including this file.
+ * The internal structure declarations are read only when that is true.
+ * Applications using the library should not include jpegint.h, but may wish
+ * to include jerror.h.
+ */
+
+#ifdef JPEG_INTERNALS
+#include "jpegint.h" /* fetch private declarations */
+#include "jerror.h" /* fetch error codes too */
+#endif
+
+#ifdef __cplusplus
+#ifndef DONT_USE_EXTERN_C
+}
+#endif
+#endif
+
+#endif /* JPEGLIB_H */