/media/libjpeg/jpegint.h

  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) */
103struct jpeg_forward_dct {
104  JMETHOD(void, start_pass, (j_compress_ptr cinfo));
105  /* perhaps this should be an array??? */
106  JMETHOD(void, forward_DCT, (j_compress_ptr cinfo,
107			      jpeg_component_info * compptr,
108			      JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
109			      JDIMENSION start_row, JDIMENSION start_col,
110			      JDIMENSION num_blocks));
111};
112
113/* Entropy encoding */
114struct jpeg_entropy_encoder {
115  JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
116  JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
117  JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
118};
119
120/* Marker writing */
121struct jpeg_marker_writer {
122  JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
123  JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
124  JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
125  JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
126  JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
127  /* These routines are exported to allow insertion of extra markers */
128  /* Probably only COM and APPn markers should be written this way */
129  JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
130				      unsigned int datalen));
131  JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
132};
133
134
135/* Declarations for decompression modules */
136
137/* Master control module */
138struct jpeg_decomp_master {
139  JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
140  JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
141
142  /* State variables made visible to other modules */
143  boolean is_dummy_pass;	/* True during 1st pass for 2-pass quant */
144};
145
146/* Input control module */
147struct jpeg_input_controller {
148  JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
149  JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
150  JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
151  JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
152
153  /* State variables made visible to other modules */
154  boolean has_multiple_scans;	/* True if file has multiple scans */
155  boolean eoi_reached;		/* True when EOI has been consumed */
156};
157
158/* Main buffer control (downsampled-data buffer) */
159struct jpeg_d_main_controller {
160  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
161  JMETHOD(void, process_data, (j_decompress_ptr cinfo,
162			       JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
163			       JDIMENSION out_rows_avail));
164};
165
166/* Coefficient buffer control */
167struct jpeg_d_coef_controller {
168  JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
169  JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
170  JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
171  JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
172				 JSAMPIMAGE output_buf));
173  /* Pointer to array of coefficient virtual arrays, or NULL if none */
174  jvirt_barray_ptr *coef_arrays;
175};
176
177/* Decompression postprocessing (color quantization buffer control) */
178struct jpeg_d_post_controller {
179  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
180  JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
181				    JSAMPIMAGE input_buf,
182				    JDIMENSION *in_row_group_ctr,
183				    JDIMENSION in_row_groups_avail,
184				    JSAMPARRAY output_buf,
185				    JDIMENSION *out_row_ctr,
186				    JDIMENSION out_rows_avail));
187};
188
189/* Marker reading & parsing */
190struct jpeg_marker_reader {
191  JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
192  /* Read markers until SOS or EOI.
193   * Returns same codes as are defined for jpeg_consume_input:
194   * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
195   */
196  JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
197  /* Read a restart marker --- exported for use by entropy decoder only */
198  jpeg_marker_parser_method read_restart_marker;
199
200  /* State of marker reader --- nominally internal, but applications
201   * supplying COM or APPn handlers might like to know the state.
202   */
203  boolean saw_SOI;		/* found SOI? */
204  boolean saw_SOF;		/* found SOF? */
205  int next_restart_num;		/* next restart number expected (0-7) */
206  unsigned int discarded_bytes;	/* # of bytes skipped looking for a marker */
207};
208
209/* Entropy decoding */
210struct jpeg_entropy_decoder {
211  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
212  JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
213				JBLOCKROW *MCU_data));
214
215  /* This is here to share code between baseline and progressive decoders; */
216  /* other modules probably should not use it */
217  boolean insufficient_data;	/* set TRUE after emitting warning */
218};
219
220/* Inverse DCT (also performs dequantization) */
221typedef JMETHOD(void, inverse_DCT_method_ptr,
222		(j_decompress_ptr cinfo, jpeg_component_info * compptr,
223		 JCOEFPTR coef_block,
224		 JSAMPARRAY output_buf, JDIMENSION output_col));
225
226struct jpeg_inverse_dct {
227  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
228  /* It is useful to allow each component to have a separate IDCT method. */
229  inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
230};
231
232/* Upsampling (note that upsampler must also call color converter) */
233struct jpeg_upsampler {
234  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
235  JMETHOD(void, upsample, (j_decompress_ptr cinfo,
236			   JSAMPIMAGE input_buf,
237			   JDIMENSION *in_row_group_ctr,
238			   JDIMENSION in_row_groups_avail,
239			   JSAMPARRAY output_buf,
240			   JDIMENSION *out_row_ctr,
241			   JDIMENSION out_rows_avail));
242
243  boolean need_context_rows;	/* TRUE if need rows above & below */
244};
245
246/* Colorspace conversion */
247struct jpeg_color_deconverter {
248  JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
249  JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
250				JSAMPIMAGE input_buf, JDIMENSION input_row,
251				JSAMPARRAY output_buf, int num_rows));
252};
253
254/* Color quantization or color precision reduction */
255struct jpeg_color_quantizer {
256  JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
257  JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
258				 JSAMPARRAY input_buf, JSAMPARRAY output_buf,
259				 int num_rows));
260  JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
261  JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
262};
263
264
265/* Miscellaneous useful macros */
266
267#undef MAX
268#define MAX(a,b)	((a) > (b) ? (a) : (b))
269#undef MIN
270#define MIN(a,b)	((a) < (b) ? (a) : (b))
271
272
273/* We assume that right shift corresponds to signed division by 2 with
274 * rounding towards minus infinity.  This is correct for typical "arithmetic
275 * shift" instructions that shift in copies of the sign bit.  But some
276 * C compilers implement >> with an unsigned shift.  For these machines you
277 * must define RIGHT_SHIFT_IS_UNSIGNED.
278 * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
279 * It is only applied with constant shift counts.  SHIFT_TEMPS must be
280 * included in the variables of any routine using RIGHT_SHIFT.
281 */
282
283#ifdef RIGHT_SHIFT_IS_UNSIGNED
284#define SHIFT_TEMPS	INT32 shift_temp;
285#define RIGHT_SHIFT(x,shft)  \
286	((shift_temp = (x)) < 0 ? \
287	 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
288	 (shift_temp >> (shft)))
289#else
290#define SHIFT_TEMPS
291#define RIGHT_SHIFT(x,shft)	((x) >> (shft))
292#endif
293
294
295/* Short forms of external names for systems with brain-damaged linkers. */
296
297#ifdef NEED_SHORT_EXTERNAL_NAMES
298#define jinit_compress_master	jICompress
299#define jinit_c_master_control	jICMaster
300#define jinit_c_main_controller	jICMainC
301#define jinit_c_prep_controller	jICPrepC
302#define jinit_c_coef_controller	jICCoefC
303#define jinit_color_converter	jICColor
304#define jinit_downsampler	jIDownsampler
305#define jinit_forward_dct	jIFDCT
306#define jinit_huff_encoder	jIHEncoder
307#define jinit_phuff_encoder	jIPHEncoder
308#define jinit_arith_encoder	jIAEncoder
309#define jinit_marker_writer	jIMWriter
310#define jinit_master_decompress	jIDMaster
311#define jinit_d_main_controller	jIDMainC
312#define jinit_d_coef_controller	jIDCoefC
313#define jinit_d_post_controller	jIDPostC
314#define jinit_input_controller	jIInCtlr
315#define jinit_marker_reader	jIMReader
316#define jinit_huff_decoder	jIHDecoder
317#define jinit_phuff_decoder	jIPHDecoder
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#define jpeg_aritab		jAriTab
334#endif /* NEED_SHORT_EXTERNAL_NAMES */
335
336
337/* Compression module initialization routines */
338EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
339EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
340					 boolean transcode_only));
341EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
342					  boolean need_full_buffer));
343EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
344					  boolean need_full_buffer));
345EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
346					  boolean need_full_buffer));
347EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
348EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
349EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
350EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
351EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo));
352EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
353EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
354/* Decompression module initialization routines */
355EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
356EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
357					  boolean need_full_buffer));
358EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
359					  boolean need_full_buffer));
360EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
361					  boolean need_full_buffer));
362EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
363EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
364EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
365EXTERN(void) jinit_phuff_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(size_t) jround_up JPP((size_t a, size_t 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 */
390
391/* Arithmetic coding probability estimation tables in jaricom.c */
392extern const INT32 jpeg_aritab[];
393
394/* Suppress undefined-structure complaints if necessary. */
395
396#ifdef INCOMPLETE_TYPES_BROKEN
397#ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */
398struct jvirt_sarray_control { long dummy; };
399struct jvirt_barray_control { long dummy; };
400#endif
401#endif /* INCOMPLETE_TYPES_BROKEN */