1 /*
2  * jpegint.h
3  *
4  * Copyright (C) 1991-1997, Thomas G. Lane.
5  * Modified 1997-2011 by Guido Vollbeding.
6  * This file is part of the Independent JPEG Group's software.
7  * For conditions of distribution and use, see the accompanying README file.
8  *
9  * This file provides common declarations for the various JPEG modules.
10  * These declarations are considered internal to the JPEG library; most
11  * applications using the library shouldn't need to include this file.
12  */
13 
14 
15 /* Declarations for both compression & decompression */
16 
17 typedef enum {			/* Operating modes for buffer controllers */
18         JBUF_PASS_THRU,		/* Plain stripwise operation */
19         /* Remaining modes require a full-image buffer to have been created */
20         JBUF_SAVE_SOURCE,	/* Run source subobject only, save output */
21         JBUF_CRANK_DEST,	/* Run dest subobject only, using saved data */
22         JBUF_SAVE_AND_PASS	/* Run both subobjects, save output */
23 } J_BUF_MODE;
24 
25 /* Values of global_state field (jdapi.c has some dependencies on ordering!) */
26 #define CSTATE_START	100	/* after create_compress */
27 #define CSTATE_SCANNING	101	/* start_compress done, write_scanlines OK */
28 #define CSTATE_RAW_OK	102	/* start_compress done, write_raw_data OK */
29 #define CSTATE_WRCOEFS	103	/* jpeg_write_coefficients done */
30 #define DSTATE_START	200	/* after create_decompress */
31 #define DSTATE_INHEADER	201	/* reading header markers, no SOS yet */
32 #define DSTATE_READY	202	/* found SOS, ready for start_decompress */
33 #define DSTATE_PRELOAD	203	/* reading multiscan file in start_decompress*/
34 #define DSTATE_PRESCAN	204	/* performing dummy pass for 2-pass quant */
35 #define DSTATE_SCANNING	205	/* start_decompress done, read_scanlines OK */
36 #define DSTATE_RAW_OK	206	/* start_decompress done, read_raw_data OK */
37 #define DSTATE_BUFIMAGE	207	/* expecting jpeg_start_output */
38 #define DSTATE_BUFPOST	208	/* looking for SOS/EOI in jpeg_finish_output */
39 #define DSTATE_RDCOEFS	209	/* reading file in jpeg_read_coefficients */
40 #define DSTATE_STOPPING	210	/* looking for EOI in jpeg_finish_decompress */
41 
42 
43 /* Declarations for compression modules */
44 
45 /* Master control module */
46 struct jpeg_comp_master {
47   JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo));
48   JMETHOD(void, pass_startup, (j_compress_ptr cinfo));
49   JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
50 
51   /* State variables made visible to other modules */
52   boolean call_pass_startup;	/* True if pass_startup must be called */
53   boolean is_last_pass;		/* True during last pass */
54 };
55 
56 /* Main buffer control (downsampled-data buffer) */
57 struct jpeg_c_main_controller {
58   JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
59   JMETHOD(void, process_data, (j_compress_ptr cinfo,
60                                JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
61                                JDIMENSION in_rows_avail));
62 };
63 
64 /* Compression preprocessing (downsampling input buffer control) */
65 struct jpeg_c_prep_controller {
66   JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
67   JMETHOD(void, pre_process_data, (j_compress_ptr cinfo,
68                                    JSAMPARRAY input_buf,
69                                    JDIMENSION *in_row_ctr,
70                                    JDIMENSION in_rows_avail,
71                                    JSAMPIMAGE output_buf,
72                                    JDIMENSION *out_row_group_ctr,
73                                    JDIMENSION out_row_groups_avail));
74 };
75 
76 /* Coefficient buffer control */
77 struct jpeg_c_coef_controller {
78   JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
79   JMETHOD(boolean, compress_data, (j_compress_ptr cinfo,
80                                    JSAMPIMAGE input_buf));
81 };
82 
83 /* Colorspace conversion */
84 struct jpeg_color_converter {
85   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
86   JMETHOD(void, color_convert, (j_compress_ptr cinfo,
87                                 JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
88                                 JDIMENSION output_row, int num_rows));
89 };
90 
91 /* Downsampling */
92 struct jpeg_downsampler {
93   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
94   JMETHOD(void, downsample, (j_compress_ptr cinfo,
95                              JSAMPIMAGE input_buf, JDIMENSION in_row_index,
96                              JSAMPIMAGE output_buf,
97                              JDIMENSION out_row_group_index));
98 
99   boolean need_context_rows;	/* TRUE if need rows above & below */
100 };
101 
102 /* Forward DCT (also controls coefficient quantization) */
103 typedef JMETHOD(void, forward_DCT_ptr,
104                 (j_compress_ptr cinfo, jpeg_component_info * compptr,
105                  JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
106                  JDIMENSION start_row, JDIMENSION start_col,
107                  JDIMENSION num_blocks));
108 
109 struct jpeg_forward_dct {
110   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
111   /* It is useful to allow each component to have a separate FDCT method. */
112   forward_DCT_ptr forward_DCT[MAX_COMPONENTS];
113 };
114 
115 /* Entropy encoding */
116 struct jpeg_entropy_encoder {
117   JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
118   JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
119   JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
120 };
121 
122 /* Marker writing */
123 struct jpeg_marker_writer {
124   JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
125   JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
126   JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
127   JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
128   JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
129   /* These routines are exported to allow insertion of extra markers */
130   /* Probably only COM and APPn markers should be written this way */
131   JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
132                                       unsigned int datalen));
133   JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
134 };
135 
136 
137 /* Declarations for decompression modules */
138 
139 /* Master control module */
140 struct jpeg_decomp_master {
141   JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
142   JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
143 
144   /* State variables made visible to other modules */
145   boolean is_dummy_pass;	/* True during 1st pass for 2-pass quant */
146 };
147 
148 /* Input control module */
149 struct jpeg_input_controller {
150   JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
151   JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
152   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
153   JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
154 
155   /* State variables made visible to other modules */
156   boolean has_multiple_scans;	/* True if file has multiple scans */
157   boolean eoi_reached;		/* True when EOI has been consumed */
158 };
159 
160 /* Main buffer control (downsampled-data buffer) */
161 struct jpeg_d_main_controller {
162   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
163   JMETHOD(void, process_data, (j_decompress_ptr cinfo,
164                                JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
165                                JDIMENSION out_rows_avail));
166 };
167 
168 /* Coefficient buffer control */
169 struct jpeg_d_coef_controller {
170   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
171   JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
172   JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
173   JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
174                                  JSAMPIMAGE output_buf));
175   /* Pointer to array of coefficient virtual arrays, or NULL if none */
176   jvirt_barray_ptr *coef_arrays;
177 };
178 
179 /* Decompression postprocessing (color quantization buffer control) */
180 struct jpeg_d_post_controller {
181   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
182   JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
183                                     JSAMPIMAGE input_buf,
184                                     JDIMENSION *in_row_group_ctr,
185                                     JDIMENSION in_row_groups_avail,
186                                     JSAMPARRAY output_buf,
187                                     JDIMENSION *out_row_ctr,
188                                     JDIMENSION out_rows_avail));
189 };
190 
191 /* Marker reading & parsing */
192 struct jpeg_marker_reader {
193   JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
194   /* Read markers until SOS or EOI.
195    * Returns same codes as are defined for jpeg_consume_input:
196    * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
197    */
198   JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
199   /* Read a restart marker --- exported for use by entropy decoder only */
200   jpeg_marker_parser_method read_restart_marker;
201 
202   /* State of marker reader --- nominally internal, but applications
203    * supplying COM or APPn handlers might like to know the state.
204    */
205   boolean saw_SOI;		/* found SOI? */
206   boolean saw_SOF;		/* found SOF? */
207   int next_restart_num;		/* next restart number expected (0-7) */
208   unsigned int discarded_bytes;	/* # of bytes skipped looking for a marker */
209 };
210 
211 /* Entropy decoding */
212 struct jpeg_entropy_decoder {
213   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
214   JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
215                                 JBLOCKROW *MCU_data));
216 };
217 
218 /* Inverse DCT (also performs dequantization) */
219 typedef JMETHOD(void, inverse_DCT_method_ptr,
220                 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
221                  JCOEFPTR coef_block,
222                  JSAMPARRAY output_buf, JDIMENSION output_col));
223 
224 struct jpeg_inverse_dct {
225   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
226   /* It is useful to allow each component to have a separate IDCT method. */
227   inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
228 };
229 
230 /* Upsampling (note that upsampler must also call color converter) */
231 struct jpeg_upsampler {
232   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
233   JMETHOD(void, upsample, (j_decompress_ptr cinfo,
234                            JSAMPIMAGE input_buf,
235                            JDIMENSION *in_row_group_ctr,
236                            JDIMENSION in_row_groups_avail,
237                            JSAMPARRAY output_buf,
238                            JDIMENSION *out_row_ctr,
239                            JDIMENSION out_rows_avail));
240 
241   boolean need_context_rows;	/* TRUE if need rows above & below */
242 };
243 
244 /* Colorspace conversion */
245 struct jpeg_color_deconverter {
246   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
247   JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
248                                 JSAMPIMAGE input_buf, JDIMENSION input_row,
249                                 JSAMPARRAY output_buf, int num_rows));
250 };
251 
252 /* Color quantization or color precision reduction */
253 struct jpeg_color_quantizer {
254   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
255   JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
256                                  JSAMPARRAY input_buf, JSAMPARRAY output_buf,
257                                  int num_rows));
258   JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
259   JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
260 };
261 
262 
263 /* Miscellaneous useful macros */
264 
265 #undef MAX
266 #define MAX(a,b)	((a) > (b) ? (a) : (b))
267 #undef MIN
268 #define MIN(a,b)	((a) < (b) ? (a) : (b))
269 
270 
271 /* We assume that right shift corresponds to signed division by 2 with
272  * rounding towards minus infinity.  This is correct for typical "arithmetic
273  * shift" instructions that shift in copies of the sign bit.  But some
274  * C compilers implement >> with an unsigned shift.  For these machines you
275  * must define RIGHT_SHIFT_IS_UNSIGNED.
276  * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
277  * It is only applied with constant shift counts.  SHIFT_TEMPS must be
278  * included in the variables of any routine using RIGHT_SHIFT.
279  */
280 
281 #ifdef RIGHT_SHIFT_IS_UNSIGNED
282 #define SHIFT_TEMPS	INT32 shift_temp;
283 #define RIGHT_SHIFT(x,shft)  \
284         ((shift_temp = (x)) < 0 ? \
285          (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
286          (shift_temp >> (shft)))
287 #else
288 #define SHIFT_TEMPS
289 #define RIGHT_SHIFT(x,shft)	((x) >> (shft))
290 #endif
291 
292 
293 /* Short forms of external names for systems with brain-damaged linkers. */
294 
295 #ifdef NEED_SHORT_EXTERNAL_NAMES
296 #define jinit_compress_master	jICompress
297 #define jinit_c_master_control	jICMaster
298 #define jinit_c_main_controller	jICMainC
299 #define jinit_c_prep_controller	jICPrepC
300 #define jinit_c_coef_controller	jICCoefC
301 #define jinit_color_converter	jICColor
302 #define jinit_downsampler	jIDownsampler
303 #define jinit_forward_dct	jIFDCT
304 #define jinit_huff_encoder	jIHEncoder
305 #define jinit_arith_encoder	jIAEncoder
306 #define jinit_marker_writer	jIMWriter
307 #define jinit_master_decompress	jIDMaster
308 #define jinit_d_main_controller	jIDMainC
309 #define jinit_d_coef_controller	jIDCoefC
310 #define jinit_d_post_controller	jIDPostC
311 #define jinit_input_controller	jIInCtlr
312 #define jinit_marker_reader	jIMReader
313 #define jinit_huff_decoder	jIHDecoder
314 #define jinit_arith_decoder	jIADecoder
315 #define jinit_inverse_dct	jIIDCT
316 #define jinit_upsampler		jIUpsampler
317 #define jinit_color_deconverter	jIDColor
318 #define jinit_1pass_quantizer	jI1Quant
319 #define jinit_2pass_quantizer	jI2Quant
320 #define jinit_merged_upsampler	jIMUpsampler
321 #define jinit_memory_mgr	jIMemMgr
322 #define jdiv_round_up		jDivRound
323 #define jround_up		jRound
324 #define jzero_far		jZeroFar
325 #define jcopy_sample_rows	jCopySamples
326 #define jcopy_block_row		jCopyBlocks
327 #define jpeg_zigzag_order	jZIGTable
328 #define jpeg_natural_order	jZAGTable
329 #define jpeg_natural_order7	jZAG7Table
330 #define jpeg_natural_order6	jZAG6Table
331 #define jpeg_natural_order5	jZAG5Table
332 #define jpeg_natural_order4	jZAG4Table
333 #define jpeg_natural_order3	jZAG3Table
334 #define jpeg_natural_order2	jZAG2Table
335 #define jpeg_aritab		jAriTab
336 #endif /* NEED_SHORT_EXTERNAL_NAMES */
337 
338 
339 /* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays
340  * and coefficient-block arrays.  This won't work on 80x86 because the arrays
341  * are FAR and we're assuming a small-pointer memory model.  However, some
342  * DOS compilers provide far-pointer versions of memcpy() and memset() even
343  * in the small-model libraries.  These will be used if USE_FMEM is defined.
344  * Otherwise, the routines in jutils.c do it the hard way.
345  */
346 
347 #ifndef NEED_FAR_POINTERS	/* normal case, same as regular macro */
348 #define FMEMZERO(target,size)	MEMZERO(target,size)
349 #else				/* 80x86 case */
350 #ifdef USE_FMEM
351 #define FMEMZERO(target,size)	_fmemset((void FAR *)(target), 0, (size_t)(size))
352 #else
353 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
354 #define FMEMZERO(target,size)	jzero_far(target, size)
355 #endif
356 #endif
357 
358 
359 /* Compression module initialization routines */
360 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
361 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
362                                          boolean transcode_only));
363 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
364                                           boolean need_full_buffer));
365 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
366                                           boolean need_full_buffer));
367 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
368                                           boolean need_full_buffer));
369 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
370 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
371 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
372 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
373 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
374 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
375 /* Decompression module initialization routines */
376 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
377 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
378                                           boolean need_full_buffer));
379 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
380                                           boolean need_full_buffer));
381 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
382                                           boolean need_full_buffer));
383 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
384 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
385 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
386 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
387 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
388 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
389 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
390 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
391 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
392 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
393 /* Memory manager initialization */
394 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
395 
396 /* Utility routines in jutils.c */
397 EXTERN(long) jdiv_round_up JPP((long a, long b));
398 EXTERN(long) jround_up JPP((long a, long b));
399 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
400                                     JSAMPARRAY output_array, int dest_row,
401                                     int num_rows, JDIMENSION num_cols));
402 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
403                                   JDIMENSION num_blocks));
404 /* Constant tables in jutils.c */
405 #if 0				/* This table is not actually needed in v6a */
406 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
407 #endif
408 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
409 extern const int jpeg_natural_order7[]; /* zz to natural order for 7x7 block */
410 extern const int jpeg_natural_order6[]; /* zz to natural order for 6x6 block */
411 extern const int jpeg_natural_order5[]; /* zz to natural order for 5x5 block */
412 extern const int jpeg_natural_order4[]; /* zz to natural order for 4x4 block */
413 extern const int jpeg_natural_order3[]; /* zz to natural order for 3x3 block */
414 extern const int jpeg_natural_order2[]; /* zz to natural order for 2x2 block */
415 
416 /* Arithmetic coding probability estimation tables in jaricom.c */
417 extern const INT32 jpeg_aritab[];
418 
419 /* Suppress undefined-structure complaints if necessary. */
420 
421 #ifdef INCOMPLETE_TYPES_BROKEN
422 #ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */
423 struct jvirt_sarray_control { long dummy; };
424 struct jvirt_barray_control { long dummy; };
425 #endif
426 #endif /* INCOMPLETE_TYPES_BROKEN */
427