1 /*
2  * jpegint.h
3  *
4  * Copyright (C) 1991-1997, Thomas G. Lane.
5  * Modified 1997-2009 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   /* This is here to share code between baseline and progressive decoders; */
218   /* other modules probably should not use it */
219   boolean insufficient_data;	/* set TRUE after emitting warning */
220 };
221 
222 /* Inverse DCT (also performs dequantization) */
223 typedef JMETHOD(void, inverse_DCT_method_ptr,
224 		(j_decompress_ptr cinfo, jpeg_component_info * compptr,
225 		 JCOEFPTR coef_block,
226 		 JSAMPARRAY output_buf, JDIMENSION output_col));
227 
228 struct jpeg_inverse_dct {
229   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
230   /* It is useful to allow each component to have a separate IDCT method. */
231   inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
232 };
233 
234 /* Upsampling (note that upsampler must also call color converter) */
235 struct jpeg_upsampler {
236   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
237   JMETHOD(void, upsample, (j_decompress_ptr cinfo,
238 			   JSAMPIMAGE input_buf,
239 			   JDIMENSION *in_row_group_ctr,
240 			   JDIMENSION in_row_groups_avail,
241 			   JSAMPARRAY output_buf,
242 			   JDIMENSION *out_row_ctr,
243 			   JDIMENSION out_rows_avail));
244 
245   boolean need_context_rows;	/* TRUE if need rows above & below */
246 };
247 
248 /* Colorspace conversion */
249 struct jpeg_color_deconverter {
250   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
251   JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
252 				JSAMPIMAGE input_buf, JDIMENSION input_row,
253 				JSAMPARRAY output_buf, int num_rows));
254 };
255 
256 /* Color quantization or color precision reduction */
257 struct jpeg_color_quantizer {
258   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
259   JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
260 				 JSAMPARRAY input_buf, JSAMPARRAY output_buf,
261 				 int num_rows));
262   JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
263   JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
264 };
265 
266 
267 /* Miscellaneous useful macros */
268 
269 #undef MAX
270 #define MAX(a,b)	((a) > (b) ? (a) : (b))
271 #undef MIN
272 #define MIN(a,b)	((a) < (b) ? (a) : (b))
273 
274 
275 /* We assume that right shift corresponds to signed division by 2 with
276  * rounding towards minus infinity.  This is correct for typical "arithmetic
277  * shift" instructions that shift in copies of the sign bit.  But some
278  * C compilers implement >> with an unsigned shift.  For these machines you
279  * must define RIGHT_SHIFT_IS_UNSIGNED.
280  * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
281  * It is only applied with constant shift counts.  SHIFT_TEMPS must be
282  * included in the variables of any routine using RIGHT_SHIFT.
283  */
284 
285 #ifdef RIGHT_SHIFT_IS_UNSIGNED
286 #define SHIFT_TEMPS	INT32 shift_temp;
287 #define RIGHT_SHIFT(x,shft)  \
288 	((shift_temp = (x)) < 0 ? \
289 	 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
290 	 (shift_temp >> (shft)))
291 #else
292 #define SHIFT_TEMPS
293 #define RIGHT_SHIFT(x,shft)	((x) >> (shft))
294 #endif
295 
296 
297 /* Short forms of external names for systems with brain-damaged linkers. */
298 
299 #ifdef NEED_SHORT_EXTERNAL_NAMES
300 #define jinit_compress_master	jICompress
301 #define jinit_c_master_control	jICMaster
302 #define jinit_c_main_controller	jICMainC
303 #define jinit_c_prep_controller	jICPrepC
304 #define jinit_c_coef_controller	jICCoefC
305 #define jinit_color_converter	jICColor
306 #define jinit_downsampler	jIDownsampler
307 #define jinit_forward_dct	jIFDCT
308 #define jinit_huff_encoder	jIHEncoder
309 #define jinit_arith_encoder	jIAEncoder
310 #define jinit_marker_writer	jIMWriter
311 #define jinit_master_decompress	jIDMaster
312 #define jinit_d_main_controller	jIDMainC
313 #define jinit_d_coef_controller	jIDCoefC
314 #define jinit_d_post_controller	jIDPostC
315 #define jinit_input_controller	jIInCtlr
316 #define jinit_marker_reader	jIMReader
317 #define jinit_huff_decoder	jIHDecoder
318 #define jinit_arith_decoder	jIADecoder
319 #define jinit_inverse_dct	jIIDCT
320 #define jinit_upsampler		jIUpsampler
321 #define jinit_color_deconverter	jIDColor
322 #define jinit_1pass_quantizer	jI1Quant
323 #define jinit_2pass_quantizer	jI2Quant
324 #define jinit_merged_upsampler	jIMUpsampler
325 #define jinit_memory_mgr	jIMemMgr
326 #define jdiv_round_up		jDivRound
327 #define jround_up		jRound
328 #define jcopy_sample_rows	jCopySamples
329 #define jcopy_block_row		jCopyBlocks
330 #define jzero_far		jZeroFar
331 #define jpeg_zigzag_order	jZIGTable
332 #define jpeg_natural_order	jZAGTable
333 #endif /* NEED_SHORT_EXTERNAL_NAMES */
334 
335 
336 /* Compression module initialization routines */
337 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
338 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
339 					 boolean transcode_only));
340 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
341 					  boolean need_full_buffer));
342 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
343 					  boolean need_full_buffer));
344 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
345 					  boolean need_full_buffer));
346 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
347 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
348 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
349 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
350 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
351 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
352 /* Decompression module initialization routines */
353 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
354 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
355 					  boolean need_full_buffer));
356 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
357 					  boolean need_full_buffer));
358 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
359 					  boolean need_full_buffer));
360 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
361 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
362 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
363 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
364 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
365 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
366 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
367 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
368 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
369 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
370 /* Memory manager initialization */
371 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
372 
373 /* Utility routines in jutils.c */
374 EXTERN(long) jdiv_round_up JPP((long a, long b));
375 EXTERN(long) jround_up JPP((long a, long b));
376 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
377 				    JSAMPARRAY output_array, int dest_row,
378 				    int num_rows, JDIMENSION num_cols));
379 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
380 				  JDIMENSION num_blocks));
381 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
382 /* Constant tables in jutils.c */
383 #if 0				/* This table is not actually needed in v6a */
384 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
385 #endif
386 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
387 
388 /* Suppress undefined-structure complaints if necessary. */
389 
390 #ifdef INCOMPLETE_TYPES_BROKEN
391 #ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */
392 struct jvirt_sarray_control { long dummy; };
393 struct jvirt_barray_control { long dummy; };
394 #endif
395 #endif /* INCOMPLETE_TYPES_BROKEN */
396