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
17typedef 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 */
46struct 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) */
57struct 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) */
65struct 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 */
77struct 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 */
84struct 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 */
92struct 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) */
103typedef 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
109struct 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 */
116struct 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 */
123struct 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 */
140struct 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 */
149struct 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) */
161struct 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 */
169struct 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) */
180struct 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 */
192struct 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 */
212struct 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) */
219typedef 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
224struct 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) */
231struct 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 */
245struct 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 */
253struct 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 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 */
337
338
339/* Compression module initialization routines */
340EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
341EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
342					 boolean transcode_only));
343EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
344					  boolean need_full_buffer));
345EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
346					  boolean need_full_buffer));
347EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
348					  boolean need_full_buffer));
349EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
350EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
351EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
352EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
353EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
354EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
355/* Decompression module initialization routines */
356EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
357EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
358					  boolean need_full_buffer));
359EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
360					  boolean need_full_buffer));
361EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
362					  boolean need_full_buffer));
363EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
364EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
365EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
366EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
367EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
368EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
369EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
370EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
371EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
372EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
373/* Memory manager initialization */
374EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
375
376/* Utility routines in jutils.c */
377EXTERN(long) jdiv_round_up JPP((long a, long b));
378EXTERN(long) jround_up JPP((long a, long b));
379EXTERN(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));
382EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
383				  JDIMENSION num_blocks));
384EXTERN(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 */
387extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
388#endif
389extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
390extern const int jpeg_natural_order7[]; /* zz to natural order for 7x7 block */
391extern const int jpeg_natural_order6[]; /* zz to natural order for 6x6 block */
392extern const int jpeg_natural_order5[]; /* zz to natural order for 5x5 block */
393extern const int jpeg_natural_order4[]; /* zz to natural order for 4x4 block */
394extern const int jpeg_natural_order3[]; /* zz to natural order for 3x3 block */
395extern const int jpeg_natural_order2[]; /* zz to natural order for 2x2 block */
396
397/* Arithmetic coding probability estimation tables in jaricom.c */
398extern const INT32 jpeg_aritab[];
399
400/* Suppress undefined-structure complaints if necessary. */
401
402#ifdef INCOMPLETE_TYPES_BROKEN
403#ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */
404struct jvirt_sarray_control { long dummy; };
405struct jvirt_barray_control { long dummy; };
406#endif
407#endif /* INCOMPLETE_TYPES_BROKEN */
408