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.
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.
15 /* Declarations for both compression & decompression */
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 */
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 */
43 /* Declarations for compression modules */
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));
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 */
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));
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,
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));
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));
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));
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));
99 boolean need_context_rows; /* TRUE if need rows above & below */
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));
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];
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));
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));
137 /* Declarations for decompression modules */
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));
144 /* State variables made visible to other modules */
145 boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */
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));
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 */
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));
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;
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));
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.
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;
202 /* State of marker reader --- nominally internal, but applications
203 * supplying COM or APPn handlers might like to know the state.
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 */
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));
218 /* Inverse DCT (also performs dequantization) */
219 typedef JMETHOD(void, inverse_DCT_method_ptr,
220 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
222 JSAMPARRAY output_buf, JDIMENSION output_col));
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];
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));
241 boolean need_context_rows; /* TRUE if need rows above & below */
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));
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,
258 JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
259 JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
263 /* Miscellaneous useful macros */
266 #define MAX(a,b) ((a) > (b) ? (a) : (b))
268 #define MIN(a,b) ((a) < (b) ? (a) : (b))
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.
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)))
289 #define RIGHT_SHIFT(x,shft) ((x) >> (shft))
293 /* Short forms of external names for systems with brain-damaged linkers. */
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 jcopy_sample_rows jCopySamples
325 #define jcopy_block_row jCopyBlocks
326 #define jzero_far jZeroFar
327 #define jpeg_zigzag_order jZIGTable
328 #define jpeg_natural_order jZAGTable
329 #define jpeg_natural_order7 jZAGTable7
330 #define jpeg_natural_order6 jZAGTable6
331 #define jpeg_natural_order5 jZAGTable5
332 #define jpeg_natural_order4 jZAGTable4
333 #define jpeg_natural_order3 jZAGTable3
334 #define jpeg_natural_order2 jZAGTable2
335 #define jpeg_aritab jAriTab
336 #endif /* NEED_SHORT_EXTERNAL_NAMES */
339 /* Compression module initialization routines */
340 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
341 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
342 boolean transcode_only));
343 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
344 boolean need_full_buffer));
345 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
346 boolean need_full_buffer));
347 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
348 boolean need_full_buffer));
349 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
350 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
351 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
352 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
353 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
354 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
355 /* Decompression module initialization routines */
356 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
357 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
358 boolean need_full_buffer));
359 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
360 boolean need_full_buffer));
361 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
362 boolean need_full_buffer));
363 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
364 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
365 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
366 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
367 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
368 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
369 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
370 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
371 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
372 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
373 /* Memory manager initialization */
374 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
376 /* Utility routines in jutils.c */
377 EXTERN(long) jdiv_round_up JPP((long a, long b));
378 EXTERN(long) jround_up JPP((long a, long b));
379 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
380 JSAMPARRAY output_array, int dest_row,
381 int num_rows, JDIMENSION num_cols));
382 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
383 JDIMENSION num_blocks));
384 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
385 /* Constant tables in jutils.c */
386 #if 0 /* This table is not actually needed in v6a */
387 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
389 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
390 extern const int jpeg_natural_order7[]; /* zz to natural order for 7x7 block */
391 extern const int jpeg_natural_order6[]; /* zz to natural order for 6x6 block */
392 extern const int jpeg_natural_order5[]; /* zz to natural order for 5x5 block */
393 extern const int jpeg_natural_order4[]; /* zz to natural order for 4x4 block */
394 extern const int jpeg_natural_order3[]; /* zz to natural order for 3x3 block */
395 extern const int jpeg_natural_order2[]; /* zz to natural order for 2x2 block */
397 /* Arithmetic coding probability estimation tables in jaricom.c */
398 extern const INT32 jpeg_aritab[];
400 /* Suppress undefined-structure complaints if necessary. */
402 #ifdef INCOMPLETE_TYPES_BROKEN
403 #ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */
404 struct jvirt_sarray_control { long dummy; };
405 struct jvirt_barray_control { long dummy; };
407 #endif /* INCOMPLETE_TYPES_BROKEN */