/src/libjpeg-turbo.main/jpegint.h

Source (jump to first uncovered line)
/*
 * jpegint.h
 *
 * This file was part of the Independent JPEG Group's software:
 * Copyright (C) 1991-1997, Thomas G. Lane.
 * Modified 1997-2009 by Guido Vollbeding.
 * libjpeg-turbo Modifications:
 * Copyright (C) 2015-2016, 2019, 2021, D. R. Commander.
 * Copyright (C) 2015, Google, Inc.
 * Copyright (C) 2021, Alex Richardson.
 * For conditions of distribution and use, see the accompanying README.ijg
 * file.
 *
 * This file provides common declarations for the various JPEG modules.
 * These declarations are considered internal to the JPEG library; most
 * applications using the library shouldn't need to include this file.
 */


/* Declarations for both compression & decompression */

typedef enum {            /* Operating modes for buffer controllers */
  JBUF_PASS_THRU,         /* Plain stripwise operation */
  /* Remaining modes require a full-image buffer to have been created */
  JBUF_SAVE_SOURCE,       /* Run source subobject only, save output */
  JBUF_CRANK_DEST,        /* Run dest subobject only, using saved data */
  JBUF_SAVE_AND_PASS      /* Run both subobjects, save output */
} J_BUF_MODE;

/* Values of global_state field (jdapi.c has some dependencies on ordering!) */
#define CSTATE_START     100    /* after create_compress */
#define CSTATE_SCANNING  101    /* start_compress done, write_scanlines OK */
#define CSTATE_RAW_OK    102    /* start_compress done, write_raw_data OK */
#define CSTATE_WRCOEFS   103    /* jpeg_write_coefficients done */
#define DSTATE_START     200    /* after create_decompress */
#define DSTATE_INHEADER  201    /* reading header markers, no SOS yet */
#define DSTATE_READY     202    /* found SOS, ready for start_decompress */
#define DSTATE_PRELOAD   203    /* reading multiscan file in start_decompress*/
#define DSTATE_PRESCAN   204    /* performing dummy pass for 2-pass quant */
#define DSTATE_SCANNING  205    /* start_decompress done, read_scanlines OK */
#define DSTATE_RAW_OK    206    /* start_decompress done, read_raw_data OK */
#define DSTATE_BUFIMAGE  207    /* expecting jpeg_start_output */
#define DSTATE_BUFPOST   208    /* looking for SOS/EOI in jpeg_finish_output */
#define DSTATE_RDCOEFS   209    /* reading file in jpeg_read_coefficients */
#define DSTATE_STOPPING  210    /* looking for EOI in jpeg_finish_decompress */


/* JLONG must hold at least signed 32-bit values. */
typedef long JLONG;

/* JUINTPTR must hold pointer values. */
#ifdef __UINTPTR_TYPE__
/*
 * __UINTPTR_TYPE__ is GNU-specific and available in GCC 4.6+ and Clang 3.0+.
 * Fortunately, that is sufficient to support the few architectures for which
 * sizeof(void *) != sizeof(size_t).  The only other options would require C99
 * or Clang-specific builtins.
 */
typedef __UINTPTR_TYPE__ JUINTPTR;
#else
typedef size_t JUINTPTR;
#endif

/*
 * Left shift macro that handles a negative operand without causing any
 * sanitizer warnings
 */

#define LEFT_SHIFT(a, b)  ((JLONG)((unsigned long)(a) << (b)))


/* Declarations for compression modules */

/* Master control module */
struct jpeg_comp_master {
  void (*prepare_for_pass) (j_compress_ptr cinfo);
  void (*pass_startup) (j_compress_ptr cinfo);
  void (*finish_pass) (j_compress_ptr cinfo);

  /* State variables made visible to other modules */
  boolean call_pass_startup;    /* True if pass_startup must be called */
  boolean is_last_pass;         /* True during last pass */
};

/* Main buffer control (downsampled-data buffer) */
struct jpeg_c_main_controller {
  void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode);
  void (*process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf,
                        JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail);
};

/* Compression preprocessing (downsampling input buffer control) */
struct jpeg_c_prep_controller {
  void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode);
  void (*pre_process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf,
                            JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail,
                            JSAMPIMAGE output_buf,
                            JDIMENSION *out_row_group_ctr,
                            JDIMENSION out_row_groups_avail);
};

/* Coefficient buffer control */
struct jpeg_c_coef_controller {
  void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode);
  boolean (*compress_data) (j_compress_ptr cinfo, JSAMPIMAGE input_buf);
};

/* Colorspace conversion */
struct jpeg_color_converter {
  void (*start_pass) (j_compress_ptr cinfo);
  void (*color_convert) (j_compress_ptr cinfo, JSAMPARRAY input_buf,
                         JSAMPIMAGE output_buf, JDIMENSION output_row,
                         int num_rows);
};

/* Downsampling */
struct jpeg_downsampler {
  void (*start_pass) (j_compress_ptr cinfo);
  void (*downsample) (j_compress_ptr cinfo, JSAMPIMAGE input_buf,
                      JDIMENSION in_row_index, JSAMPIMAGE output_buf,
                      JDIMENSION out_row_group_index);

  boolean need_context_rows;    /* TRUE if need rows above & below */
};

/* Forward DCT (also controls coefficient quantization) */
struct jpeg_forward_dct {
  void (*start_pass) (j_compress_ptr cinfo);
  /* perhaps this should be an array??? */
  void (*forward_DCT) (j_compress_ptr cinfo, jpeg_component_info *compptr,
                       JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
                       JDIMENSION start_row, JDIMENSION start_col,
                       JDIMENSION num_blocks);
};

/* Entropy encoding */
struct jpeg_entropy_encoder {
  void (*start_pass) (j_compress_ptr cinfo, boolean gather_statistics);
  boolean (*encode_mcu) (j_compress_ptr cinfo, JBLOCKROW *MCU_data);
  void (*finish_pass) (j_compress_ptr cinfo);
};

/* Marker writing */
struct jpeg_marker_writer {
  void (*write_file_header) (j_compress_ptr cinfo);
  void (*write_frame_header) (j_compress_ptr cinfo);
  void (*write_scan_header) (j_compress_ptr cinfo);
  void (*write_file_trailer) (j_compress_ptr cinfo);
  void (*write_tables_only) (j_compress_ptr cinfo);
  /* These routines are exported to allow insertion of extra markers */
  /* Probably only COM and APPn markers should be written this way */
  void (*write_marker_header) (j_compress_ptr cinfo, int marker,
                               unsigned int datalen);
  void (*write_marker_byte) (j_compress_ptr cinfo, int val);
};


/* Declarations for decompression modules */

/* Master control module */
struct jpeg_decomp_master {
  void (*prepare_for_output_pass) (j_decompress_ptr cinfo);
  void (*finish_output_pass) (j_decompress_ptr cinfo);

  /* State variables made visible to other modules */
  boolean is_dummy_pass;        /* True during 1st pass for 2-pass quant */

  /* Partial decompression variables */
  JDIMENSION first_iMCU_col;
  JDIMENSION last_iMCU_col;
  JDIMENSION first_MCU_col[MAX_COMPONENTS];
  JDIMENSION last_MCU_col[MAX_COMPONENTS];
  boolean jinit_upsampler_no_alloc;

  /* Last iMCU row that was successfully decoded */
  JDIMENSION last_good_iMCU_row;
};

/* Input control module */
struct jpeg_input_controller {
  int (*consume_input) (j_decompress_ptr cinfo);
  void (*reset_input_controller) (j_decompress_ptr cinfo);
  void (*start_input_pass) (j_decompress_ptr cinfo);
  void (*finish_input_pass) (j_decompress_ptr cinfo);

  /* State variables made visible to other modules */
  boolean has_multiple_scans;   /* True if file has multiple scans */
  boolean eoi_reached;          /* True when EOI has been consumed */
};

/* Main buffer control (downsampled-data buffer) */
struct jpeg_d_main_controller {
  void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode);
  void (*process_data) (j_decompress_ptr cinfo, JSAMPARRAY output_buf,
                        JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail);
};

/* Coefficient buffer control */
struct jpeg_d_coef_controller {
  void (*start_input_pass) (j_decompress_ptr cinfo);
  int (*consume_data) (j_decompress_ptr cinfo);
  void (*start_output_pass) (j_decompress_ptr cinfo);
  int (*decompress_data) (j_decompress_ptr cinfo, JSAMPIMAGE output_buf);
  /* Pointer to array of coefficient virtual arrays, or NULL if none */
  jvirt_barray_ptr *coef_arrays;
};

/* Decompression postprocessing (color quantization buffer control) */
struct jpeg_d_post_controller {
  void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode);
  void (*post_process_data) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
                             JDIMENSION *in_row_group_ctr,
                             JDIMENSION in_row_groups_avail,
                             JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
                             JDIMENSION out_rows_avail);
};

/* Marker reading & parsing */
struct jpeg_marker_reader {
  void (*reset_marker_reader) (j_decompress_ptr cinfo);
  /* Read markers until SOS or EOI.
   * Returns same codes as are defined for jpeg_consume_input:
   * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
   */
  int (*read_markers) (j_decompress_ptr cinfo);
  /* Read a restart marker --- exported for use by entropy decoder only */
  jpeg_marker_parser_method read_restart_marker;

  /* State of marker reader --- nominally internal, but applications
   * supplying COM or APPn handlers might like to know the state.
   */
  boolean saw_SOI;              /* found SOI? */
  boolean saw_SOF;              /* found SOF? */
  int next_restart_num;         /* next restart number expected (0-7) */
  unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
};

/* Entropy decoding */
struct jpeg_entropy_decoder {
  void (*start_pass) (j_decompress_ptr cinfo);
  boolean (*decode_mcu) (j_decompress_ptr cinfo, JBLOCKROW *MCU_data);

  /* This is here to share code between baseline and progressive decoders; */
  /* other modules probably should not use it */
  boolean insufficient_data;    /* set TRUE after emitting warning */
};

/* Inverse DCT (also performs dequantization) */
typedef void (*inverse_DCT_method_ptr) (j_decompress_ptr cinfo,
                                        jpeg_component_info *compptr,
                                        JCOEFPTR coef_block,
                                        JSAMPARRAY output_buf,
                                        JDIMENSION output_col);

struct jpeg_inverse_dct {
  void (*start_pass) (j_decompress_ptr cinfo);
  /* It is useful to allow each component to have a separate IDCT method. */
  inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
};

/* Upsampling (note that upsampler must also call color converter) */
struct jpeg_upsampler {
  void (*start_pass) (j_decompress_ptr cinfo);
  void (*upsample) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
                    JDIMENSION *in_row_group_ctr,
                    JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf,
                    JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail);

  boolean need_context_rows;    /* TRUE if need rows above & below */
};

/* Colorspace conversion */
struct jpeg_color_deconverter {
  void (*start_pass) (j_decompress_ptr cinfo);
  void (*color_convert) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
                         JDIMENSION input_row, JSAMPARRAY output_buf,
                         int num_rows);
};

/* Color quantization or color precision reduction */
struct jpeg_color_quantizer {
  void (*start_pass) (j_decompress_ptr cinfo, boolean is_pre_scan);
  void (*color_quantize) (j_decompress_ptr cinfo, JSAMPARRAY input_buf,
                          JSAMPARRAY output_buf, int num_rows);
  void (*finish_pass) (j_decompress_ptr cinfo);
  void (*new_color_map) (j_decompress_ptr cinfo);
};


/* Miscellaneous useful macros */

#undef MAX
#define MAX(a, b)       ((a) > (b) ? (a) : (b))
#undef MIN
#define MIN(a, b)       ((a) < (b) ? (a) : (b))


/* We assume that right shift corresponds to signed division by 2 with
 * rounding towards minus infinity.  This is correct for typical "arithmetic
 * shift" instructions that shift in copies of the sign bit.  But some
 * C compilers implement >> with an unsigned shift.  For these machines you
 * must define RIGHT_SHIFT_IS_UNSIGNED.
 * RIGHT_SHIFT provides a proper signed right shift of a JLONG quantity.
 * It is only applied with constant shift counts.  SHIFT_TEMPS must be
 * included in the variables of any routine using RIGHT_SHIFT.
 */

#ifdef RIGHT_SHIFT_IS_UNSIGNED
#define SHIFT_TEMPS     JLONG shift_temp;
#define RIGHT_SHIFT(x, shft) \
  ((shift_temp = (x)) < 0 ? \
   (shift_temp >> (shft)) | ((~((JLONG)0)) << (32 - (shft))) : \
   (shift_temp >> (shft)))
#else
#define SHIFT_TEMPS
#define RIGHT_SHIFT(x, shft)    ((x) >> (shft))
#endif


/* Compression module initialization routines */
EXTERN(void) jinit_compress_master(j_compress_ptr cinfo);
EXTERN(void) jinit_c_master_control(j_compress_ptr cinfo,
                                    boolean transcode_only);
EXTERN(void) jinit_c_main_controller(j_compress_ptr cinfo,
                                     boolean need_full_buffer);
EXTERN(void) jinit_c_prep_controller(j_compress_ptr cinfo,
                                     boolean need_full_buffer);
EXTERN(void) jinit_c_coef_controller(j_compress_ptr cinfo,
                                     boolean need_full_buffer);
EXTERN(void) jinit_color_converter(j_compress_ptr cinfo);
EXTERN(void) jinit_downsampler(j_compress_ptr cinfo);
EXTERN(void) jinit_forward_dct(j_compress_ptr cinfo);
EXTERN(void) jinit_huff_encoder(j_compress_ptr cinfo);
EXTERN(void) jinit_phuff_encoder(j_compress_ptr cinfo);
EXTERN(void) jinit_arith_encoder(j_compress_ptr cinfo);
EXTERN(void) jinit_marker_writer(j_compress_ptr cinfo);
/* Decompression module initialization routines */
EXTERN(void) jinit_master_decompress(j_decompress_ptr cinfo);
EXTERN(void) jinit_d_main_controller(j_decompress_ptr cinfo,
                                     boolean need_full_buffer);
EXTERN(void) jinit_d_coef_controller(j_decompress_ptr cinfo,
                                     boolean need_full_buffer);
EXTERN(void) jinit_d_post_controller(j_decompress_ptr cinfo,
                                     boolean need_full_buffer);
EXTERN(void) jinit_input_controller(j_decompress_ptr cinfo);
EXTERN(void) jinit_marker_reader(j_decompress_ptr cinfo);
EXTERN(void) jinit_huff_decoder(j_decompress_ptr cinfo);
EXTERN(void) jinit_phuff_decoder(j_decompress_ptr cinfo);
EXTERN(void) jinit_arith_decoder(j_decompress_ptr cinfo);
EXTERN(void) jinit_inverse_dct(j_decompress_ptr cinfo);
EXTERN(void) jinit_upsampler(j_decompress_ptr cinfo);
EXTERN(void) jinit_color_deconverter(j_decompress_ptr cinfo);
EXTERN(void) jinit_1pass_quantizer(j_decompress_ptr cinfo);
EXTERN(void) jinit_2pass_quantizer(j_decompress_ptr cinfo);
EXTERN(void) jinit_merged_upsampler(j_decompress_ptr cinfo);
/* Memory manager initialization */
EXTERN(void) jinit_memory_mgr(j_common_ptr cinfo);

/* Utility routines in jutils.c */
EXTERN(long) jdiv_round_up(long a, long b);
EXTERN(long) jround_up(long a, long b);
EXTERN(void) jcopy_sample_rows(JSAMPARRAY input_array, int source_row,
                               JSAMPARRAY output_array, int dest_row,
                               int num_rows, JDIMENSION num_cols);
EXTERN(void) jcopy_block_row(JBLOCKROW input_row, JBLOCKROW output_row,
                             JDIMENSION num_blocks);
EXTERN(void) jzero_far(void *target, size_t bytestozero);
/* Constant tables in jutils.c */
#if 0                           /* This table is not actually needed in v6a */
extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
#endif
extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */

/* Arithmetic coding probability estimation tables in jaricom.c */
extern const JLONG jpeg_aritab[];

Coverage Report

Created: 2024-05-12 13:53

Line	Count	Source (jump to first uncovered line)
1		/*
2		* jpegint.h
3		*
4		* This file was part of the Independent JPEG Group's software:
5		* Copyright (C) 1991-1997, Thomas G. Lane.
6		* Modified 1997-2009 by Guido Vollbeding.
7		* libjpeg-turbo Modifications:
8		* Copyright (C) 2015-2016, 2019, 2021, D. R. Commander.
9		* Copyright (C) 2015, Google, Inc.
10		* Copyright (C) 2021, Alex Richardson.
11		* For conditions of distribution and use, see the accompanying README.ijg
12		* file.
13		*
14		* This file provides common declarations for the various JPEG modules.
15		* These declarations are considered internal to the JPEG library; most
16		* applications using the library shouldn't need to include this file.
17		*/
18
19
20		/* Declarations for both compression & decompression */
21
22		typedef enum { /* Operating modes for buffer controllers */
23		JBUF_PASS_THRU, /* Plain stripwise operation */
24		/* Remaining modes require a full-image buffer to have been created */
25		JBUF_SAVE_SOURCE, /* Run source subobject only, save output */
26		JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */
27		JBUF_SAVE_AND_PASS /* Run both subobjects, save output */
28		} J_BUF_MODE;
29
30		/* Values of global_state field (jdapi.c has some dependencies on ordering!) */
31	0	#define CSTATE_START 100 /* after create_compress */
32	0	#define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */
33	0	#define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */
34	0	#define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */
35	201k	#define DSTATE_START 200 /* after create_decompress */
36	83.0k	#define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */
37	80.4k	#define DSTATE_READY 202 /* found SOS, ready for start_decompress */
38	49.2k	#define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/
39	25.8k	#define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */
40	3.93M	#define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */
41	0	#define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */
42	0	#define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */
43	0	#define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */
44	0	#define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */
45	8.09k	#define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */
46
47
48		/* JLONG must hold at least signed 32-bit values. */
49		typedef long JLONG;
50
51		/* JUINTPTR must hold pointer values. */
52		#ifdef __UINTPTR_TYPE__
53		/*
54		* __UINTPTR_TYPE__ is GNU-specific and available in GCC 4.6+ and Clang 3.0+.
55		* Fortunately, that is sufficient to support the few architectures for which
56		* sizeof(void *) != sizeof(size_t). The only other options would require C99
57		* or Clang-specific builtins.
58		*/
59		typedef __UINTPTR_TYPE__ JUINTPTR;
60		#else
61		typedef size_t JUINTPTR;
62		#endif
63
64		/*
65		* Left shift macro that handles a negative operand without causing any
66		* sanitizer warnings
67		*/
68
69	6.19M	#define LEFT_SHIFT(a, b) ((JLONG)((unsigned long)(a) << (b)))
70
71
72		/* Declarations for compression modules */
73
74		/* Master control module */
75		struct jpeg_comp_master {
76		void (*prepare_for_pass) (j_compress_ptr cinfo);
77		void (*pass_startup) (j_compress_ptr cinfo);
78		void (*finish_pass) (j_compress_ptr cinfo);
79
80		/* State variables made visible to other modules */
81		boolean call_pass_startup; /* True if pass_startup must be called */
82		boolean is_last_pass; /* True during last pass */
83		};
84
85		/* Main buffer control (downsampled-data buffer) */
86		struct jpeg_c_main_controller {
87		void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode);
88		void (*process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf,
89		JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail);
90		};
91
92		/* Compression preprocessing (downsampling input buffer control) */
93		struct jpeg_c_prep_controller {
94		void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode);
95		void (*pre_process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf,
96		JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail,
97		JSAMPIMAGE output_buf,
98		JDIMENSION *out_row_group_ctr,
99		JDIMENSION out_row_groups_avail);
100		};
101
102		/* Coefficient buffer control */
103		struct jpeg_c_coef_controller {
104		void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode);
105		boolean (*compress_data) (j_compress_ptr cinfo, JSAMPIMAGE input_buf);
106		};
107
108		/* Colorspace conversion */
109		struct jpeg_color_converter {
110		void (*start_pass) (j_compress_ptr cinfo);
111		void (*color_convert) (j_compress_ptr cinfo, JSAMPARRAY input_buf,
112		JSAMPIMAGE output_buf, JDIMENSION output_row,
113		int num_rows);
114		};
115
116		/* Downsampling */
117		struct jpeg_downsampler {
118		void (*start_pass) (j_compress_ptr cinfo);
119		void (*downsample) (j_compress_ptr cinfo, JSAMPIMAGE input_buf,
120		JDIMENSION in_row_index, JSAMPIMAGE output_buf,
121		JDIMENSION out_row_group_index);
122
123		boolean need_context_rows; /* TRUE if need rows above & below */
124		};
125
126		/* Forward DCT (also controls coefficient quantization) */
127		struct jpeg_forward_dct {
128		void (*start_pass) (j_compress_ptr cinfo);
129		/* perhaps this should be an array??? */
130		void (forward_DCT) (j_compress_ptr cinfo, jpeg_component_info compptr,
131		JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
132		JDIMENSION start_row, JDIMENSION start_col,
133		JDIMENSION num_blocks);
134		};
135
136		/* Entropy encoding */
137		struct jpeg_entropy_encoder {
138		void (*start_pass) (j_compress_ptr cinfo, boolean gather_statistics);
139		boolean (encode_mcu) (j_compress_ptr cinfo, JBLOCKROW MCU_data);
140		void (*finish_pass) (j_compress_ptr cinfo);
141		};
142
143		/* Marker writing */
144		struct jpeg_marker_writer {
145		void (*write_file_header) (j_compress_ptr cinfo);
146		void (*write_frame_header) (j_compress_ptr cinfo);
147		void (*write_scan_header) (j_compress_ptr cinfo);
148		void (*write_file_trailer) (j_compress_ptr cinfo);
149		void (*write_tables_only) (j_compress_ptr cinfo);
150		/* These routines are exported to allow insertion of extra markers */
151		/* Probably only COM and APPn markers should be written this way */
152		void (*write_marker_header) (j_compress_ptr cinfo, int marker,
153		unsigned int datalen);
154		void (*write_marker_byte) (j_compress_ptr cinfo, int val);
155		};
156
157
158		/* Declarations for decompression modules */
159
160		/* Master control module */
161		struct jpeg_decomp_master {
162		void (*prepare_for_output_pass) (j_decompress_ptr cinfo);
163		void (*finish_output_pass) (j_decompress_ptr cinfo);
164
165		/* State variables made visible to other modules */
166		boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */
167
168		/* Partial decompression variables */
169		JDIMENSION first_iMCU_col;
170		JDIMENSION last_iMCU_col;
171		JDIMENSION first_MCU_col[MAX_COMPONENTS];
172		JDIMENSION last_MCU_col[MAX_COMPONENTS];
173		boolean jinit_upsampler_no_alloc;
174
175		/* Last iMCU row that was successfully decoded */
176		JDIMENSION last_good_iMCU_row;
177		};
178
179		/* Input control module */
180		struct jpeg_input_controller {
181		int (*consume_input) (j_decompress_ptr cinfo);
182		void (*reset_input_controller) (j_decompress_ptr cinfo);
183		void (*start_input_pass) (j_decompress_ptr cinfo);
184		void (*finish_input_pass) (j_decompress_ptr cinfo);
185
186		/* State variables made visible to other modules */
187		boolean has_multiple_scans; /* True if file has multiple scans */
188		boolean eoi_reached; /* True when EOI has been consumed */
189		};
190
191		/* Main buffer control (downsampled-data buffer) */
192		struct jpeg_d_main_controller {
193		void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode);
194		void (*process_data) (j_decompress_ptr cinfo, JSAMPARRAY output_buf,
195		JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail);
196		};
197
198		/* Coefficient buffer control */
199		struct jpeg_d_coef_controller {
200		void (*start_input_pass) (j_decompress_ptr cinfo);
201		int (*consume_data) (j_decompress_ptr cinfo);
202		void (*start_output_pass) (j_decompress_ptr cinfo);
203		int (*decompress_data) (j_decompress_ptr cinfo, JSAMPIMAGE output_buf);
204		/* Pointer to array of coefficient virtual arrays, or NULL if none */
205		jvirt_barray_ptr *coef_arrays;
206		};
207
208		/* Decompression postprocessing (color quantization buffer control) */
209		struct jpeg_d_post_controller {
210		void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode);
211		void (*post_process_data) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
212		JDIMENSION *in_row_group_ctr,
213		JDIMENSION in_row_groups_avail,
214		JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
215		JDIMENSION out_rows_avail);
216		};
217
218		/* Marker reading & parsing */
219		struct jpeg_marker_reader {
220		void (*reset_marker_reader) (j_decompress_ptr cinfo);
221		/* Read markers until SOS or EOI.
222		* Returns same codes as are defined for jpeg_consume_input:
223		* JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
224		*/
225		int (*read_markers) (j_decompress_ptr cinfo);
226		/* Read a restart marker --- exported for use by entropy decoder only */
227		jpeg_marker_parser_method read_restart_marker;
228
229		/* State of marker reader --- nominally internal, but applications
230		* supplying COM or APPn handlers might like to know the state.
231		*/
232		boolean saw_SOI; /* found SOI? */
233		boolean saw_SOF; /* found SOF? */
234		int next_restart_num; /* next restart number expected (0-7) */
235		unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
236		};
237
238		/* Entropy decoding */
239		struct jpeg_entropy_decoder {
240		void (*start_pass) (j_decompress_ptr cinfo);
241		boolean (decode_mcu) (j_decompress_ptr cinfo, JBLOCKROW MCU_data);
242
243		/* This is here to share code between baseline and progressive decoders; */
244		/* other modules probably should not use it */
245		boolean insufficient_data; /* set TRUE after emitting warning */
246		};
247
248		/* Inverse DCT (also performs dequantization) */
249		typedef void (*inverse_DCT_method_ptr) (j_decompress_ptr cinfo,
250		jpeg_component_info *compptr,
251		JCOEFPTR coef_block,
252		JSAMPARRAY output_buf,
253		JDIMENSION output_col);
254
255		struct jpeg_inverse_dct {
256		void (*start_pass) (j_decompress_ptr cinfo);
257		/* It is useful to allow each component to have a separate IDCT method. */
258		inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
259		};
260
261		/* Upsampling (note that upsampler must also call color converter) */
262		struct jpeg_upsampler {
263		void (*start_pass) (j_decompress_ptr cinfo);
264		void (*upsample) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
265		JDIMENSION *in_row_group_ctr,
266		JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf,
267		JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail);
268
269		boolean need_context_rows; /* TRUE if need rows above & below */
270		};
271
272		/* Colorspace conversion */
273		struct jpeg_color_deconverter {
274		void (*start_pass) (j_decompress_ptr cinfo);
275		void (*color_convert) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
276		JDIMENSION input_row, JSAMPARRAY output_buf,
277		int num_rows);
278		};
279
280		/* Color quantization or color precision reduction */
281		struct jpeg_color_quantizer {
282		void (*start_pass) (j_decompress_ptr cinfo, boolean is_pre_scan);
283		void (*color_quantize) (j_decompress_ptr cinfo, JSAMPARRAY input_buf,
284		JSAMPARRAY output_buf, int num_rows);
285		void (*finish_pass) (j_decompress_ptr cinfo);
286		void (*new_color_map) (j_decompress_ptr cinfo);
287		};
288
289
290		/* Miscellaneous useful macros */
291
292		#undef MAX
293	2.55M	#define MAX(a, b) ((a) > (b) ? (a) : (b))
294		#undef MIN
295	204k	#define MIN(a, b) ((a) < (b) ? (a) : (b))
296
297
298		/* We assume that right shift corresponds to signed division by 2 with
299		* rounding towards minus infinity. This is correct for typical "arithmetic
300		* shift" instructions that shift in copies of the sign bit. But some
301		* C compilers implement >> with an unsigned shift. For these machines you
302		* must define RIGHT_SHIFT_IS_UNSIGNED.
303		* RIGHT_SHIFT provides a proper signed right shift of a JLONG quantity.
304		* It is only applied with constant shift counts. SHIFT_TEMPS must be
305		* included in the variables of any routine using RIGHT_SHIFT.
306		*/
307
308		#ifdef RIGHT_SHIFT_IS_UNSIGNED
309		#define SHIFT_TEMPS JLONG shift_temp;
310		#define RIGHT_SHIFT(x, shft) \
311		((shift_temp = (x)) < 0 ? \
312		(shift_temp >> (shft)) \| ((~((JLONG)0)) << (32 - (shft))) : \
313		(shift_temp >> (shft)))
314		#else
315		#define SHIFT_TEMPS
316	4.88M	#define RIGHT_SHIFT(x, shft) ((x) >> (shft))
317		#endif
318
319
320		/* Compression module initialization routines */
321		EXTERN(void) jinit_compress_master(j_compress_ptr cinfo);
322		EXTERN(void) jinit_c_master_control(j_compress_ptr cinfo,
323		boolean transcode_only);
324		EXTERN(void) jinit_c_main_controller(j_compress_ptr cinfo,
325		boolean need_full_buffer);
326		EXTERN(void) jinit_c_prep_controller(j_compress_ptr cinfo,
327		boolean need_full_buffer);
328		EXTERN(void) jinit_c_coef_controller(j_compress_ptr cinfo,
329		boolean need_full_buffer);
330		EXTERN(void) jinit_color_converter(j_compress_ptr cinfo);
331		EXTERN(void) jinit_downsampler(j_compress_ptr cinfo);
332		EXTERN(void) jinit_forward_dct(j_compress_ptr cinfo);
333		EXTERN(void) jinit_huff_encoder(j_compress_ptr cinfo);
334		EXTERN(void) jinit_phuff_encoder(j_compress_ptr cinfo);
335		EXTERN(void) jinit_arith_encoder(j_compress_ptr cinfo);
336		EXTERN(void) jinit_marker_writer(j_compress_ptr cinfo);
337		/* Decompression module initialization routines */
338		EXTERN(void) jinit_master_decompress(j_decompress_ptr cinfo);
339		EXTERN(void) jinit_d_main_controller(j_decompress_ptr cinfo,
340		boolean need_full_buffer);
341		EXTERN(void) jinit_d_coef_controller(j_decompress_ptr cinfo,
342		boolean need_full_buffer);
343		EXTERN(void) jinit_d_post_controller(j_decompress_ptr cinfo,
344		boolean need_full_buffer);
345		EXTERN(void) jinit_input_controller(j_decompress_ptr cinfo);
346		EXTERN(void) jinit_marker_reader(j_decompress_ptr cinfo);
347		EXTERN(void) jinit_huff_decoder(j_decompress_ptr cinfo);
348		EXTERN(void) jinit_phuff_decoder(j_decompress_ptr cinfo);
349		EXTERN(void) jinit_arith_decoder(j_decompress_ptr cinfo);
350		EXTERN(void) jinit_inverse_dct(j_decompress_ptr cinfo);
351		EXTERN(void) jinit_upsampler(j_decompress_ptr cinfo);
352		EXTERN(void) jinit_color_deconverter(j_decompress_ptr cinfo);
353		EXTERN(void) jinit_1pass_quantizer(j_decompress_ptr cinfo);
354		EXTERN(void) jinit_2pass_quantizer(j_decompress_ptr cinfo);
355		EXTERN(void) jinit_merged_upsampler(j_decompress_ptr cinfo);
356		/* Memory manager initialization */
357		EXTERN(void) jinit_memory_mgr(j_common_ptr cinfo);
358
359		/* Utility routines in jutils.c */
360		EXTERN(long) jdiv_round_up(long a, long b);
361		EXTERN(long) jround_up(long a, long b);
362		EXTERN(void) jcopy_sample_rows(JSAMPARRAY input_array, int source_row,
363		JSAMPARRAY output_array, int dest_row,
364		int num_rows, JDIMENSION num_cols);
365		EXTERN(void) jcopy_block_row(JBLOCKROW input_row, JBLOCKROW output_row,
366		JDIMENSION num_blocks);
367		EXTERN(void) jzero_far(void *target, size_t bytestozero);
368		/* Constant tables in jutils.c */
369		#if 0 /* This table is not actually needed in v6a */
370		extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
371		#endif
372		extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
373
374		/* Arithmetic coding probability estimation tables in jaricom.c */
375		extern const JLONG jpeg_aritab[];