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(void, reset_input_controller, (j_decompress_ptr cinfo));
149 JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
150 JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
151
152 /* State variables made visible to other modules */
153 boolean has_multiple_scans; /* True if file has multiple scans */
154 boolean eoi_reached; /* True when EOI has been consumed */
155};
156
157/* Main buffer control (downsampled-data buffer) */
158struct jpeg_d_main_controller {
159 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
160 JMETHOD(void, process_data, (j_decompress_ptr cinfo,
161 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
162 JDIMENSION out_rows_avail));
163};
164
165/* Coefficient buffer control */
166struct jpeg_d_coef_controller {
167 JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
168 JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
169 JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
170 JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
171 JSAMPIMAGE output_buf));
172 /* Pointer to array of coefficient virtual arrays, or NULL if none */
173 jvirt_barray_ptr *coef_arrays;
174};
175
176/* Decompression postprocessing (color quantization buffer control) */
177struct jpeg_d_post_controller {
178 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
179 JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
180 JSAMPIMAGE input_buf,
181 JDIMENSION *in_row_group_ctr,
182 JDIMENSION in_row_groups_avail,
183 JSAMPARRAY output_buf,
184 JDIMENSION *out_row_ctr,
185 JDIMENSION out_rows_avail));
186};
187
188/* Marker reading & parsing */
189struct jpeg_marker_reader {
190 JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
191 /* Read markers until SOS or EOI.
192 * Returns same codes as are defined for jpeg_consume_input:
193 * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
194 */
195 JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
196 /* Read a restart marker --- exported for use by entropy decoder only */
197 jpeg_marker_parser_method read_restart_marker;
198
199 /* State of marker reader --- nominally internal, but applications
200 * supplying COM or APPn handlers might like to know the state.
201 */
202 boolean saw_SOI; /* found SOI? */
203 boolean saw_SOF; /* found SOF? */
204 int next_restart_num; /* next restart number expected (0-7) */
205 unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
206};
207
208/* Entropy decoding */
209struct jpeg_entropy_decoder {
210 JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
211 JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
212 JBLOCKROW *MCU_data));
213
214 /* This is here to share code between baseline and progressive decoders; */
215 /* other modules probably should not use it */
216 boolean insufficient_data; /* set TRUE after emitting warning */
217};
218
219/* Inverse DCT (also performs dequantization) */
220typedef JMETHOD(void, inverse_DCT_method_ptr,
221 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
222 JCOEFPTR coef_block,
223 JSAMPARRAY output_buf, JDIMENSION output_col));
224
225struct jpeg_inverse_dct {
226 JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
227 /* It is useful to allow each component to have a separate IDCT method. */
228 inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
229};
230
231/* Upsampling (note that upsampler must also call color converter) */
232struct jpeg_upsampler {
233 JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
234 JMETHOD(void, upsample, (j_decompress_ptr cinfo,
235 JSAMPIMAGE input_buf,
236 JDIMENSION *in_row_group_ctr,
237 JDIMENSION in_row_groups_avail,
238 JSAMPARRAY output_buf,
239 JDIMENSION *out_row_ctr,
240 JDIMENSION out_rows_avail));
241
242 boolean need_context_rows; /* TRUE if need rows above & below */
243};
244
245/* Colorspace conversion */
246struct jpeg_color_deconverter {
247 JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
248 JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
249 JSAMPIMAGE input_buf, JDIMENSION input_row,
250 JSAMPARRAY output_buf, int num_rows));
251};
252
253/* Color quantization or color precision reduction */
254struct jpeg_color_quantizer {
255 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
256 JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
257 JSAMPARRAY input_buf, JSAMPARRAY output_buf,
258 int num_rows));
259 JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
260 JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
261};
262
263
264/* Miscellaneous useful macros */
265
266#undef MAX
267#define MAX(a,b) ((a) > (b) ? (a) : (b))
268#undef MIN
269#define MIN(a,b) ((a) < (b) ? (a) : (b))
270
271
272/* We assume that right shift corresponds to signed division by 2 with
273 * rounding towards minus infinity. This is correct for typical "arithmetic
274 * shift" instructions that shift in copies of the sign bit. But some
275 * C compilers implement >> with an unsigned shift. For these machines you
276 * must define RIGHT_SHIFT_IS_UNSIGNED.
277 * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
278 * It is only applied with constant shift counts. SHIFT_TEMPS must be
279 * included in the variables of any routine using RIGHT_SHIFT.
280 */
281
282#ifdef RIGHT_SHIFT_IS_UNSIGNED
283#define SHIFT_TEMPS INT32 shift_temp;
284#define RIGHT_SHIFT(x,shft) \
285 ((shift_temp = (x)) < 0 ? \
286 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
287 (shift_temp >> (shft)))
288#else
289#define SHIFT_TEMPS
290#define RIGHT_SHIFT(x,shft) ((x) >> (shft))
291#endif
292
293
294/* Short forms of external names for systems with brain-damaged linkers. */
295
296#ifdef NEED_SHORT_EXTERNAL_NAMES
297#define jinit_compress_master jICompress
298#define jinit_c_master_control jICMaster
299#define jinit_c_main_controller jICMainC
300#define jinit_c_prep_controller jICPrepC
301#define jinit_c_coef_controller jICCoefC
302#define jinit_color_converter jICColor
303#define jinit_downsampler jIDownsampler
304#define jinit_forward_dct jIFDCT
305#define jinit_huff_encoder jIHEncoder
306#define jinit_phuff_encoder jIPHEncoder
307#define jinit_marker_writer jIMWriter
308#define jinit_master_decompress jIDMaster
309#define jinit_d_main_controller jIDMainC
310#define jinit_d_coef_controller jIDCoefC
311#define jinit_d_post_controller jIDPostC
312#define jinit_input_controller jIInCtlr
313#define jinit_marker_reader jIMReader
314#define jinit_huff_decoder jIHDecoder
315#define jinit_phuff_decoder jIPHDecoder
316#define jinit_inverse_dct jIIDCT
317#define jinit_upsampler jIUpsampler
318#define jinit_color_deconverter jIDColor
319#define jinit_1pass_quantizer jI1Quant
320#define jinit_2pass_quantizer jI2Quant
321#define jinit_merged_upsampler jIMUpsampler
322#define jinit_memory_mgr jIMemMgr
323#define jdiv_round_up jDivRound
324#define jround_up jRound
325#define jcopy_sample_rows jCopySamples
326#define jcopy_block_row jCopyBlocks
327#define jzero_far jZeroFar
328#define jpeg_zigzag_order jZIGTable
329#define jpeg_natural_order jZAGTable
330#endif /* NEED_SHORT_EXTERNAL_NAMES */
331
332
333/* Compression module initialization routines */
334EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
335EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
336 boolean transcode_only));
337EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
338 boolean need_full_buffer));
339EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
340 boolean need_full_buffer));
341EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
342 boolean need_full_buffer));
343EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
344EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
345EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
346EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
347EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo));
348EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
349/* Decompression module initialization routines */
350EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
351EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
352 boolean need_full_buffer));
353EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
354 boolean need_full_buffer));
355EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
356 boolean need_full_buffer));
357EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
358EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
359EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
360EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo));
361EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
362EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
363EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
364EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
365EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
366EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
367/* Memory manager initialization */
368EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
369
370/* Utility routines in jutils.c */
371EXTERN(long) jdiv_round_up JPP((long a, long b));
372EXTERN(long) jround_up JPP((long a, long b));
373EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
374 JSAMPARRAY output_array, int dest_row,
375 int num_rows, JDIMENSION num_cols));
376EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
377 JDIMENSION num_blocks));
378EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
379/* Constant tables in jutils.c */
380#if 0 /* This table is not actually needed in v6a */
381extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
382#endif
383extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
384
385/* Suppress undefined-structure complaints if necessary. */
386
387#ifdef INCOMPLETE_TYPES_BROKEN
388#ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */
389struct jvirt_sarray_control { long dummy; };
390struct jvirt_barray_control { long dummy; };
391#endif
392#endif /* INCOMPLETE_TYPES_BROKEN */
393