1/*
2 * jpegint.h
3 *
4 * Copyright (C) 1991-1997, Thomas G. Lane.
5 * This file is part of the Independent JPEG Group's software.
6 * For conditions of distribution and use, see the accompanying README file.
7 *
8 * This file provides common declarations for the various JPEG modules.
9 * These declarations are considered internal to the JPEG library; most
10 * applications using the library shouldn't need to include this file.
11 */
12
13
14/* Declarations for both compression & decompression */
15
16typedef enum {			/* Operating modes for buffer controllers */
17	JBUF_PASS_THRU,		/* Plain stripwise operation */
18	/* Remaining modes require a full-image buffer to have been created */
19	JBUF_SAVE_SOURCE,	/* Run source subobject only, save output */
20	JBUF_CRANK_DEST,	/* Run dest subobject only, using saved data */
21	JBUF_SAVE_AND_PASS	/* Run both subobjects, save output */
22} J_BUF_MODE;
23
24/* Values of global_state field (jdapi.c has some dependencies on ordering!) */
25#define CSTATE_START	100	/* after create_compress */
26#define CSTATE_SCANNING	101	/* start_compress done, write_scanlines OK */
27#define CSTATE_RAW_OK	102	/* start_compress done, write_raw_data OK */
28#define CSTATE_WRCOEFS	103	/* jpeg_write_coefficients done */
29#define DSTATE_START	200	/* after create_decompress */
30#define DSTATE_INHEADER	201	/* reading header markers, no SOS yet */
31#define DSTATE_READY	202	/* found SOS, ready for start_decompress */
32#define DSTATE_PRELOAD	203	/* reading multiscan file in start_decompress*/
33#define DSTATE_PRESCAN	204	/* performing dummy pass for 2-pass quant */
34#define DSTATE_SCANNING	205	/* start_decompress done, read_scanlines OK */
35#define DSTATE_RAW_OK	206	/* start_decompress done, read_raw_data OK */
36#define DSTATE_BUFIMAGE	207	/* expecting jpeg_start_output */
37#define DSTATE_BUFPOST	208	/* looking for SOS/EOI in jpeg_finish_output */
38#define DSTATE_RDCOEFS	209	/* reading file in jpeg_read_coefficients */
39#define DSTATE_STOPPING	210	/* looking for EOI in jpeg_finish_decompress */
40
41
42/* Declarations for compression modules */
43
44/* Master control module */
45struct jpeg_comp_master {
46  JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo));
47  JMETHOD(void, pass_startup, (j_compress_ptr cinfo));
48  JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
49
50  /* State variables made visible to other modules */
51  boolean call_pass_startup;	/* True if pass_startup must be called */
52  boolean is_last_pass;		/* True during last pass */
53};
54
55/* Main buffer control (downsampled-data buffer) */
56struct jpeg_c_main_controller {
57  JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
58  JMETHOD(void, process_data, (j_compress_ptr cinfo,
59			       JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
60			       JDIMENSION in_rows_avail));
61};
62
63/* Compression preprocessing (downsampling input buffer control) */
64struct jpeg_c_prep_controller {
65  JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
66  JMETHOD(void, pre_process_data, (j_compress_ptr cinfo,
67				   JSAMPARRAY input_buf,
68				   JDIMENSION *in_row_ctr,
69				   JDIMENSION in_rows_avail,
70				   JSAMPIMAGE output_buf,
71				   JDIMENSION *out_row_group_ctr,
72				   JDIMENSION out_row_groups_avail));
73};
74
75/* Coefficient buffer control */
76struct jpeg_c_coef_controller {
77  JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
78  JMETHOD(boolean, compress_data, (j_compress_ptr cinfo,
79				   JSAMPIMAGE input_buf));
80};
81
82/* Colorspace conversion */
83struct jpeg_color_converter {
84  JMETHOD(void, start_pass, (j_compress_ptr cinfo));
85  JMETHOD(void, color_convert, (j_compress_ptr cinfo,
86				JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
87				JDIMENSION output_row, int num_rows));
88};
89
90/* Downsampling */
91struct jpeg_downsampler {
92  JMETHOD(void, start_pass, (j_compress_ptr cinfo));
93  JMETHOD(void, downsample, (j_compress_ptr cinfo,
94			     JSAMPIMAGE input_buf, JDIMENSION in_row_index,
95			     JSAMPIMAGE output_buf,
96			     JDIMENSION out_row_group_index));
97
98  boolean need_context_rows;	/* TRUE if need rows above & below */
99};
100
101/* Forward DCT (also controls coefficient quantization) */
102struct jpeg_forward_dct {
103  JMETHOD(void, start_pass, (j_compress_ptr cinfo));
104  /* perhaps this should be an array??? */
105  JMETHOD(void, forward_DCT, (j_compress_ptr cinfo,
106			      jpeg_component_info * compptr,
107			      JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
108			      JDIMENSION start_row, JDIMENSION start_col,
109			      JDIMENSION num_blocks));
110};
111
112/* Entropy encoding */
113struct jpeg_entropy_encoder {
114  JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
115  JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
116  JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
117};
118
119/* Marker writing */
120struct jpeg_marker_writer {
121  JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
122  JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
123  JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
124  JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
125  JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
126  /* These routines are exported to allow insertion of extra markers */
127  /* Probably only COM and APPn markers should be written this way */
128  JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
129				      unsigned int datalen));
130  JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
131};
132
133
134/* Declarations for decompression modules */
135
136/* Master control module */
137struct jpeg_decomp_master {
138  JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
139  JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
140
141  /* State variables made visible to other modules */
142  boolean is_dummy_pass;	/* True during 1st pass for 2-pass quant */
143};
144
145/* Input control module */
146struct jpeg_input_controller {
147  JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
148  JMETHOD(int, consume_input_build_huffman_index, (j_decompress_ptr cinfo,
149                    huffman_index *index, int scan_count));
150  JMETHOD(int, consume_markers, (j_decompress_ptr cinfo,
151                    huffman_index *index, int scan_count));
152  JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
153  JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
154  JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
155
156  /* State variables made visible to other modules */
157  boolean has_multiple_scans;	/* True if file has multiple scans */
158  boolean eoi_reached;		/* True when EOI has been consumed */
159};
160
161/* Main buffer control (downsampled-data buffer) */
162struct jpeg_d_main_controller {
163  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
164  JMETHOD(void, process_data, (j_decompress_ptr cinfo,
165			       JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
166			       JDIMENSION out_rows_avail));
167};
168
169/* Coefficient buffer control */
170struct jpeg_d_coef_controller {
171  JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
172  JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
173  JMETHOD(int, consume_data_build_huffman_index, (j_decompress_ptr cinfo,
174                    huffman_index* index, int scan_count));
175  JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
176  JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
177				 JSAMPIMAGE output_buf));
178  /* Pointer to array of coefficient virtual arrays, or NULL if none */
179  jvirt_barray_ptr *coef_arrays;
180
181  /* column number of the first and last tile, respectively */
182  int column_left_boundary;
183  int column_right_boundary;
184
185  /* column number of the first and last MCU, respectively */
186  int MCU_column_left_boundary;
187  int MCU_column_right_boundary;
188
189  /* the number of MCU columns to skip from the indexed MCU, iM,
190   * to the requested MCU boundary, rM, where iM is the MCU that we sample
191   * into our index and is the nearest one to the left of rM.
192   */
193  int MCU_columns_to_skip;
194};
195
196/* Decompression postprocessing (color quantization buffer control) */
197struct jpeg_d_post_controller {
198  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
199  JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
200				    JSAMPIMAGE input_buf,
201				    JDIMENSION *in_row_group_ctr,
202				    JDIMENSION in_row_groups_avail,
203				    JSAMPARRAY output_buf,
204				    JDIMENSION *out_row_ctr,
205				    JDIMENSION out_rows_avail));
206};
207
208/* Marker reading & parsing */
209struct jpeg_marker_reader {
210  JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
211  /* Read markers until SOS or EOI.
212   * Returns same codes as are defined for jpeg_consume_input:
213   * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
214   */
215  JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
216  JMETHOD(void, get_sos_marker_position, (j_decompress_ptr cinfo,
217                    huffman_index *index));
218  /* Read a restart marker --- exported for use by entropy decoder only */
219  jpeg_marker_parser_method read_restart_marker;
220
221  /* State of marker reader --- nominally internal, but applications
222   * supplying COM or APPn handlers might like to know the state.
223   */
224  boolean saw_SOI;		/* found SOI? */
225  boolean saw_SOF;		/* found SOF? */
226  int next_restart_num;		/* next restart number expected (0-7) */
227  int current_sos_marker_position;
228  unsigned int discarded_bytes;	/* # of bytes skipped looking for a marker */
229};
230
231/* Entropy decoding */
232struct jpeg_entropy_decoder {
233  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
234  JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
235				JBLOCKROW *MCU_data));
236  JMETHOD(boolean, decode_mcu_discard_coef, (j_decompress_ptr cinfo));
237  JMETHOD(void, configure_huffman_decoder, (j_decompress_ptr cinfo,
238                    huffman_offset_data offset));
239  JMETHOD(void, get_huffman_decoder_configuration, (j_decompress_ptr cinfo,
240                    huffman_offset_data *offset));
241
242  /* This is here to share code between baseline and progressive decoders; */
243  /* other modules probably should not use it */
244  boolean insufficient_data;	/* set TRUE after emitting warning */
245
246  huffman_index *index;
247};
248
249/* Inverse DCT (also performs dequantization) */
250typedef JMETHOD(void, inverse_DCT_method_ptr,
251		(j_decompress_ptr cinfo, jpeg_component_info * compptr,
252		 JCOEFPTR coef_block,
253		 JSAMPARRAY output_buf, JDIMENSION output_col));
254
255struct jpeg_inverse_dct {
256  JMETHOD(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) */
262struct jpeg_upsampler {
263  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
264  JMETHOD(void, upsample, (j_decompress_ptr cinfo,
265			   JSAMPIMAGE input_buf,
266			   JDIMENSION *in_row_group_ctr,
267			   JDIMENSION in_row_groups_avail,
268			   JSAMPARRAY output_buf,
269			   JDIMENSION *out_row_ctr,
270			   JDIMENSION out_rows_avail));
271
272  boolean need_context_rows;	/* TRUE if need rows above & below */
273};
274
275/* Colorspace conversion */
276struct jpeg_color_deconverter {
277  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
278  JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
279				JSAMPIMAGE input_buf, JDIMENSION input_row,
280				JSAMPARRAY output_buf, int num_rows));
281};
282
283/* Color quantization or color precision reduction */
284struct jpeg_color_quantizer {
285  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
286  JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
287				 JSAMPARRAY input_buf, JSAMPARRAY output_buf,
288				 int num_rows));
289  JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
290  JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
291};
292
293
294/* Miscellaneous useful macros */
295
296#undef MAX
297#define MAX(a,b)	((a) > (b) ? (a) : (b))
298#undef MIN
299#define MIN(a,b)	((a) < (b) ? (a) : (b))
300
301
302/* We assume that right shift corresponds to signed division by 2 with
303 * rounding towards minus infinity.  This is correct for typical "arithmetic
304 * shift" instructions that shift in copies of the sign bit.  But some
305 * C compilers implement >> with an unsigned shift.  For these machines you
306 * must define RIGHT_SHIFT_IS_UNSIGNED.
307 * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
308 * It is only applied with constant shift counts.  SHIFT_TEMPS must be
309 * included in the variables of any routine using RIGHT_SHIFT.
310 */
311
312#ifdef RIGHT_SHIFT_IS_UNSIGNED
313#define SHIFT_TEMPS	INT32 shift_temp;
314#define RIGHT_SHIFT(x,shft)  \
315	((shift_temp = (x)) < 0 ? \
316	 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
317	 (shift_temp >> (shft)))
318#else
319#define SHIFT_TEMPS
320#define RIGHT_SHIFT(x,shft)	((x) >> (shft))
321#endif
322
323
324/* Short forms of external names for systems with brain-damaged linkers. */
325
326#ifdef NEED_SHORT_EXTERNAL_NAMES
327#define jinit_compress_master	jICompress
328#define jinit_c_master_control	jICMaster
329#define jinit_c_main_controller	jICMainC
330#define jinit_c_prep_controller	jICPrepC
331#define jinit_c_coef_controller	jICCoefC
332#define jinit_color_converter	jICColor
333#define jinit_downsampler	jIDownsampler
334#define jinit_forward_dct	jIFDCT
335#define jinit_huff_encoder	jIHEncoder
336#define jinit_phuff_encoder	jIPHEncoder
337#define jinit_marker_writer	jIMWriter
338#define jinit_master_decompress	jIDMaster
339#define jinit_d_main_controller	jIDMainC
340#define jinit_d_coef_controller	jIDCoefC
341#define jinit_d_post_controller	jIDPostC
342#define jinit_input_controller	jIInCtlr
343#define jinit_marker_reader	jIMReader
344#define jinit_huff_decoder	jIHDecoder
345#define jinit_phuff_decoder	jIPHDecoder
346#define jinit_inverse_dct	jIIDCT
347#define jinit_upsampler		jIUpsampler
348#define jinit_color_deconverter	jIDColor
349#define jinit_1pass_quantizer	jI1Quant
350#define jinit_2pass_quantizer	jI2Quant
351#define jinit_merged_upsampler	jIMUpsampler
352#define jinit_memory_mgr	jIMemMgr
353#define jdiv_round_up		jDivRound
354#define jround_up		jRound
355#define jcopy_sample_rows	jCopySamples
356#define jcopy_block_row		jCopyBlocks
357#define jzero_far		jZeroFar
358#define jpeg_zigzag_order	jZIGTable
359#define jpeg_natural_order	jZAGTable
360#endif /* NEED_SHORT_EXTERNAL_NAMES */
361
362
363/* Compression module initialization routines */
364EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
365EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
366					 boolean transcode_only));
367EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
368					  boolean need_full_buffer));
369EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
370					  boolean need_full_buffer));
371EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
372					  boolean need_full_buffer));
373EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
374EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
375EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
376EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
377EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo));
378EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
379/* Decompression module initialization routines */
380EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
381EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
382					  boolean need_full_buffer));
383EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
384					  boolean need_full_buffer));
385EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
386					  boolean need_full_buffer));
387EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
388EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
389EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
390EXTERN(void) jinit_huff_decoder_no_data JPP((j_decompress_ptr cinfo));
391EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo));
392EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
393EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
394EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
395EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
396EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
397EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
398EXTERN(void) jpeg_decompress_per_scan_setup (j_decompress_ptr cinfo);
399/* Memory manager initialization */
400EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
401
402/* Utility routines in jutils.c */
403EXTERN(long) jdiv_round_up JPP((long a, long b));
404EXTERN(long) jround_up JPP((long a, long b));
405EXTERN(long) jmin JPP((long a, long b));
406EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
407				    JSAMPARRAY output_array, int dest_row,
408				    int num_rows, JDIMENSION num_cols));
409EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
410				  JDIMENSION num_blocks));
411EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
412
413EXTERN(void) jset_input_stream_position JPP((j_decompress_ptr cinfo,
414                    int offset));
415EXTERN(void) jset_input_stream_position_bit JPP((j_decompress_ptr cinfo,
416                    int byte_offset, int bit_left, INT32 buf));
417
418EXTERN(int) jget_input_stream_position JPP((j_decompress_ptr cinfo));
419/* Constant tables in jutils.c */
420#if 0				/* This table is not actually needed in v6a */
421extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
422#endif
423extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
424
425/* Suppress undefined-structure complaints if necessary. */
426
427#ifdef INCOMPLETE_TYPES_BROKEN
428#ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */
429struct jvirt_sarray_control { long dummy; };
430struct jvirt_barray_control { long dummy; };
431#endif
432#endif /* INCOMPLETE_TYPES_BROKEN */
433