This is jpeglib.h in view mode; [Download] [Up]
/*
* jpeglib.h
*
* Copyright (C) 1991-1994, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file defines the application interface for the JPEG library.
* Most applications using the library need only include this file,
* and perhaps jerror.h if they want to know the exact error codes.
*/
#ifndef JPEGLIB_H
#define JPEGLIB_H
/*
* First we include the configuration files that record how this
* installation of the JPEG library is set up. jconfig.h can be
* generated automatically for many systems. jmorecfg.h contains
* manual configuration options that most people need not worry about.
*/
#ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
#include "jconfig.h" /* widely used configuration options */
#endif
#include "jmorecfg.h" /* seldom changed options */
/* Version ID for the JPEG library.
* Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
*/
#define JPEG_LIB_VERSION 51 /* Version 5a */
/* Various constants determining the sizes of things.
* All of these are specified by the JPEG standard, so don't change them
* if you want to be compatible.
*/
#define DCTSIZE 8 /* The basic DCT block is 8x8 samples */
#define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
#define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
#define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
#define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
#define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
#define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
#define MAX_BLOCKS_IN_MCU 10 /* JPEG limit on # of blocks in an MCU */
/* This macro is used to declare a "method", that is, a function pointer.
* We want to supply prototype parameters if the compiler can cope.
* Note that the arglist parameter must be parenthesized!
*/
#ifdef HAVE_PROTOTYPES
#define JMETHOD(type,methodname,arglist) type (*methodname) arglist
#else
#define JMETHOD(type,methodname,arglist) type (*methodname) ()
#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 field directly represents the contents of a JPEG DQT marker.
* Note: the values are always given 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. */
int dc_tbl_no; /* DC entropy table selector (0..3) */
int ac_tbl_no; /* AC entropy table selector (0..3) */
/* Remaining fields should be treated as private by applications. */
/* These values are computed during compression or decompression startup: */
/* Component's size in DCT blocks.
* Any dummy blocks added to complete an MCU are not counted; therefore
* these values do not depend on whether a scan is interleaved or not.
*/
JDIMENSION width_in_blocks;
JDIMENSION height_in_blocks;
/* Size of a DCT block in samples. Always DCTSIZE for compression.
* For decompression this is the size of the output from one DCT block,
* reflecting any scaling we choose to apply during the IDCT step.
* Values of 1,2,4,8 are likely to be supported. Note that different
* components may receive different IDCT scalings.
*/
int DCT_scaled_size;
/* The downsampled dimensions are the component's actual, unpadded number
* of samples at the main buffer (preprocessing/compression interface), thus
* downsampled_width = ceil(image_width * Hi/Hmax)
* and similarly for height. For decompression, IDCT scaling is included, so
* downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
*/
JDIMENSION downsampled_width; /* actual width in samples */
JDIMENSION downsampled_height; /* actual height in samples */
/* This flag is used only for decompression. In cases where some of the
* components will be ignored (eg grayscale output from YCbCr image),
* we can skip most computations for the unused components.
*/
boolean component_needed; /* do we need the value of this component? */
/* These values are computed before starting a scan of the component: */
int MCU_width; /* number of blocks per MCU, horizontally */
int MCU_height; /* number of blocks per MCU, vertically */
int MCU_blocks; /* MCU_width * MCU_height */
int MCU_sample_width; /* MCU width in samples, MCU_width*DCT_scaled_size */
int last_col_width; /* # of non-dummy blocks across in last MCU */
int last_row_height; /* # of non-dummy blocks down in last MCU */
/* Private per-component storage for DCT or IDCT subsystem. */
void * dct_table;
} jpeg_component_info;
/* 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 */\
boolean is_decompressor; /* so common code can tell which is which */\
int global_state /* for checking call sequence validity */
/* Routines that are to be used by both halves of the library are declared
* to receive a pointer to this structure. There are no actual instances of
* jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
*/
struct jpeg_common_struct {
jpeg_common_fields; /* Fields common to both master struct types */
/* Additional fields follow in an actual jpeg_compress_struct or
* jpeg_decompress_struct. All three structs must agree on these
* initial fields! (This would be a lot cleaner in C++.)
*/
};
typedef struct jpeg_common_struct * j_common_ptr;
typedef struct jpeg_compress_struct * j_compress_ptr;
typedef struct jpeg_decompress_struct * j_decompress_ptr;
/* Master record for a compression instance */
struct jpeg_compress_struct {
jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */
/* Destination for compressed data */
struct jpeg_destination_mgr * dest;
/* Description of source image --- these fields must be filled in by
* outer application before starting compression. in_color_space must
* be correct before you can even call jpeg_set_defaults().
*/
JDIMENSION image_width; /* input image width */
JDIMENSION image_height; /* input image height */
int input_components; /* # of color components in input image */
J_COLOR_SPACE in_color_space; /* colorspace of input image */
double input_gamma; /* image gamma of input image */
/* Compression parameters --- these fields must be set before calling
* jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
* initialize everything to reasonable defaults, then changing anything
* the application specifically wants to change. That way you won't get
* burnt when new parameters are added. Also note that there are several
* helper routines to simplify changing parameters.
*/
int data_precision; /* bits of precision in image data */
int num_components; /* # of color components in JPEG image */
J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
jpeg_component_info * comp_info;
/* comp_info[i] describes component that appears i'th in SOF */
JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
/* ptrs to coefficient quantization tables, or NULL if not defined */
JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
/* ptrs to Huffman coding tables, or NULL if not defined */
UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
boolean raw_data_in; /* TRUE=caller supplies downsampled data */
boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
boolean interleave; /* TRUE=interleaved output, FALSE=not */
boolean optimize_coding; /* TRUE=optimize entropy encoding parms */
boolean CCIR601_sampling; /* TRUE=first samples are cosited */
int smoothing_factor; /* 1..100, or 0 for no input smoothing */
J_DCT_METHOD dct_method; /* DCT algorithm selector */
/* The restart interval can be specified in absolute MCUs by setting
* restart_interval, or in MCU rows by setting restart_in_rows
* (in which case the correct restart_interval will be figured
* for each scan).
*/
unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
int restart_in_rows; /* if > 0, MCU rows per restart interval */
/* Parameters controlling emission of special markers. */
boolean write_JFIF_header; /* should a JFIF marker be written? */
/* 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
*/
int max_h_samp_factor; /* largest h_samp_factor */
int max_v_samp_factor; /* largest v_samp_factor */
JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */
/* The coefficient controller receives data in units of MCU rows as defined
* for fully interleaved scans (whether the JPEG file is interleaved or not).
* There are v_samp_factor * DCTSIZE sample rows of each component in an
* "iMCU" (interleaved MCU) row.
*/
/*
* These fields are valid during any one scan.
* They describe the components and MCUs actually appearing in the scan.
*/
int comps_in_scan; /* # of JPEG components in this scan */
jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
/* *cur_comp_info[i] describes component that appears i'th in SOS */
JDIMENSION MCUs_per_row; /* # of MCUs across the image */
JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
int blocks_in_MCU; /* # of DCT blocks per MCU */
int MCU_membership[MAX_BLOCKS_IN_MCU];
/* MCU_membership[i] is index in cur_comp_info of component owning */
/* i'th block in an MCU */
/*
* 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;
};
/* 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 raw_data_out; /* TRUE=downsampled data wanted */
boolean quantize_colors; /* TRUE=colormapped output wanted */
/* the following are ignored if not quantize_colors: */
boolean two_pass_quantize; /* TRUE=use two-pass color quantization */
J_DITHER_MODE dither_mode; /* type of color dithering to use */
int desired_number_of_colors; /* max number of colors to use */
J_DCT_METHOD dct_method; /* DCT algorithm selector */
boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */
/* 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.
* 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 variable: index of next scaled 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 */
/* Internal JPEG parameters --- the application usually need not look at
* these fields.
*/
/* 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 */
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 */
boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
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: */
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 */
/* Remaining fields are known throughout decompressor, but generally
* should not be touched by a surrounding application.
*/
/*
* These fields are computed during decompression startup
*/
int max_h_samp_factor; /* largest h_samp_factor */
int max_v_samp_factor; /* largest v_samp_factor */
int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */
JDIMENSION total_iMCU_rows; /* # of iMCU rows to be output by coef ctlr */
/* The coefficient controller outputs 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 * DCT_scaled_size sample rows of each component
* in an "iMCU" (interleaved MCU) 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.
*/
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[MAX_BLOCKS_IN_MCU];
/* MCU_membership[i] is index in cur_comp_info of component owning */
/* i'th block in an MCU */
/* 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_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));
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,
JDIMENSION samplesperrow,
JDIMENSION numrows,
JDIMENSION unitheight));
JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
int pool_id,
JDIMENSION blocksperrow,
JDIMENSION numrows,
JDIMENSION unitheight));
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,
boolean writable));
JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
jvirt_barray_ptr ptr,
JDIMENSION start_row,
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;
};
/* 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_create_compress jCreaCompress
#define jpeg_create_decompress jCreaDecompress
#define jpeg_destroy_compress jDestCompress
#define jpeg_destroy_decompress jDestDecompress
#define jpeg_stdio_dest jStdDest
#define jpeg_stdio_src jStdSrc
#define jpeg_set_defaults jSetDefaults
#define jpeg_set_colorspace jSetColorspace
#define jpeg_default_colorspace jDefColorspace
#define jpeg_set_quality jSetQuality
#define jpeg_set_linear_quality jSetLQuality
#define jpeg_add_quant_table jAddQuantTable
#define jpeg_quality_scaling jQualityScaling
#define jpeg_suppress_tables jSuppressTables
#define jpeg_alloc_quant_table jAlcQTable
#define jpeg_alloc_huff_table jAlcHTable
#define jpeg_start_compress jStrtCompress
#define jpeg_write_scanlines jWrtScanlines
#define jpeg_finish_compress jFinCompress
#define jpeg_write_raw_data jWrtRawData
#define jpeg_write_marker jWrtMarker
#define jpeg_write_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_calc_output_dimensions jCalcDimensions
#define jpeg_set_marker_processor jSetMarker
#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 and destruction of JPEG compression objects */
/* NB: you must set up the error-manager BEFORE calling jpeg_create_xxx */
EXTERN void jpeg_create_compress JPP((j_compress_ptr cinfo));
EXTERN void jpeg_create_decompress JPP((j_decompress_ptr cinfo));
EXTERN void jpeg_destroy_compress JPP((j_compress_ptr cinfo));
EXTERN void jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
/* Standard data source and destination managers: stdio streams. */
/* Caller is responsible for opening the file before and closing after. */
EXTERN void jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
EXTERN void jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
/* Default parameter setup for compression */
EXTERN void jpeg_set_defaults JPP((j_compress_ptr cinfo));
/* Compression parameter setup aids */
EXTERN void jpeg_set_colorspace JPP((j_compress_ptr cinfo,
J_COLOR_SPACE colorspace));
EXTERN void jpeg_default_colorspace JPP((j_compress_ptr cinfo));
EXTERN void jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
boolean force_baseline));
EXTERN void jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
int scale_factor,
boolean force_baseline));
EXTERN void jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
const unsigned int *basic_table,
int scale_factor,
boolean force_baseline));
EXTERN int jpeg_quality_scaling JPP((int quality));
EXTERN void jpeg_suppress_tables JPP((j_compress_ptr cinfo,
boolean suppress));
EXTERN JQUANT_TBL * jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
EXTERN JHUFF_TBL * jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
/* Main entry points for compression */
EXTERN void jpeg_start_compress JPP((j_compress_ptr cinfo,
boolean write_all_tables));
EXTERN JDIMENSION jpeg_write_scanlines JPP((j_compress_ptr cinfo,
JSAMPARRAY scanlines,
JDIMENSION num_lines));
EXTERN void jpeg_finish_compress JPP((j_compress_ptr cinfo));
/* Replaces jpeg_write_scanlines when writing raw downsampled data. */
EXTERN JDIMENSION jpeg_write_raw_data JPP((j_compress_ptr cinfo,
JSAMPIMAGE data,
JDIMENSION num_lines));
/* Write a special marker. See libjpeg.doc concerning safe usage. */
EXTERN void jpeg_write_marker JPP((j_compress_ptr cinfo, int marker,
const JOCTET *dataptr, unsigned int datalen));
/* 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_HEADER_OK 0 /* Found valid image datastream */
#define JPEG_HEADER_TABLES_ONLY 1 /* Found valid table-specs-only datastream */
#define JPEG_SUSPENDED 2 /* Had to suspend before end of headers */
/* 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 void 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));
/* Precalculate output dimensions for current decompression parameters. */
EXTERN void jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
/* 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));
/* 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));
/* 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_marker_reader { long dummy; };
struct jpeg_entropy_decoder { long dummy; };
struct jpeg_inverse_dct { long dummy; };
struct jpeg_upsampler { long dummy; };
struct jpeg_color_deconverter { long dummy; };
struct jpeg_color_quantizer { long dummy; };
#endif /* JPEG_INTERNALS */
#endif /* INCOMPLETE_TYPES_BROKEN */
/*
* The JPEG library modules define JPEG_INTERNALS before including this file.
* The internal structure declarations are read only when that is true.
* Applications using the library should not include jpegint.h, but may wish
* to include jerror.h.
*/
#ifdef JPEG_INTERNALS
#include "jpegint.h" /* fetch private declarations */
#include "jerror.h" /* fetch error codes too */
#endif
#endif /* JPEGLIB_H */
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.