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jcapimin.c
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1 /*
2 * jcapimin.c
3 *
4 * Copyright (C) 1994-1998, 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 contains application interface code for the compression half
9 * of the JPEG library. These are the "minimum" API routines that may be
10 * needed in either the normal full-compression case or the transcoding-only
11 * case.
12 *
13 * Most of the routines intended to be called directly by an application
14 * are in this file or in jcapistd.c. But also see jcparam.c for
15 * parameter-setup helper routines, jcomapi.c for routines shared by
16 * compression and decompression, and jctrans.c for the transcoding case.
17 */
18
19 #define JPEG_INTERNALS
20 #include "jinclude.h"
21 #include "jpeglib.h"
22
23
24 /*
25 * Initialization of a JPEG compression object.
26 * The error manager must already be set up (in case memory manager fails).
27 */
28
29 GLOBAL(void)
30 jpeg_CreateCompress (j_compress_ptr cinfo, int version, size_t structsize)
31 {
32 int i;
33
34 /* Guard against version mismatches between library and caller. */
35 cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */
36 if (version != JPEG_LIB_VERSION)
37 ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
38 if (structsize != SIZEOF(struct jpeg_compress_struct))
39 ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE,
40 (int) SIZEOF(struct jpeg_compress_struct), (int) structsize);
41
42 /* For debugging purposes, we zero the whole master structure.
43 * But the application has already set the err pointer, and may have set
44 * client_data, so we have to save and restore those fields.
45 * Note: if application hasn't set client_data, tools like Purify may
46 * complain here.
47 */
48 {
49 struct jpeg_error_mgr * err = cinfo->err;
50 void * client_data = cinfo->client_data; /* ignore Purify complaint here */
51 MEMZERO(cinfo, SIZEOF(struct jpeg_compress_struct));
52 cinfo->err = err;
53 cinfo->client_data = client_data;
54 }
55 cinfo->is_decompressor = FALSE;
56
57 /* Initialize a memory manager instance for this object */
58 jinit_memory_mgr((j_common_ptr) cinfo);
59
60 /* Zero out pointers to permanent structures. */
61 cinfo->progress = NULL;
62 cinfo->dest = NULL;
63
64 cinfo->comp_info = NULL;
65
66 for (i = 0; i < NUM_QUANT_TBLS; i++)
67 cinfo->quant_tbl_ptrs[i] = NULL;
68
69 for (i = 0; i < NUM_HUFF_TBLS; i++) {
70 cinfo->dc_huff_tbl_ptrs[i] = NULL;
71 cinfo->ac_huff_tbl_ptrs[i] = NULL;
72 }
73
74 cinfo->script_space = NULL;
75
76 cinfo->input_gamma = 1.0; /* in case application forgets */
77
78 /* OK, I'm ready */
79 cinfo->global_state = CSTATE_START;
80 }
81
82
83 /*
84 * Destruction of a JPEG compression object
85 */
86
87 GLOBAL(void)
88 jpeg_destroy_compress (j_compress_ptr cinfo)
89 {
90 jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
91 }
92
93
94 /*
95 * Abort processing of a JPEG compression operation,
96 * but don't destroy the object itself.
97 */
98
99 GLOBAL(void)
100 jpeg_abort_compress (j_compress_ptr cinfo)
101 {
102 jpeg_abort((j_common_ptr) cinfo); /* use common routine */
103 }
104
105
106 /*
107 * Forcibly suppress or un-suppress all quantization and Huffman tables.
108 * Marks all currently defined tables as already written (if suppress)
109 * or not written (if !suppress). This will control whether they get emitted
110 * by a subsequent jpeg_start_compress call.
111 *
112 * This routine is exported for use by applications that want to produce
113 * abbreviated JPEG datastreams. It logically belongs in jcparam.c, but
114 * since it is called by jpeg_start_compress, we put it here --- otherwise
115 * jcparam.o would be linked whether the application used it or not.
116 */
117
118 GLOBAL(void)
119 jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)
120 {
121 int i;
122 JQUANT_TBL * qtbl;
123 JHUFF_TBL * htbl;
124
125 for (i = 0; i < NUM_QUANT_TBLS; i++) {
126 if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
127 qtbl->sent_table = suppress;
128 }
129
130 for (i = 0; i < NUM_HUFF_TBLS; i++) {
131 if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
132 htbl->sent_table = suppress;
133 if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
134 htbl->sent_table = suppress;
135 }
136 }
137
138
139 /*
140 * Finish JPEG compression.
141 *
142 * If a multipass operating mode was selected, this may do a great deal of
143 * work including most of the actual output.
144 */
145
146 GLOBAL(void)
147 jpeg_finish_compress (j_compress_ptr cinfo)
148 {
149 JDIMENSION iMCU_row;
150
151 if (cinfo->global_state == CSTATE_SCANNING ||
152 cinfo->global_state == CSTATE_RAW_OK) {
153 /* Terminate first pass */
154 if (cinfo->next_scanline < cinfo->image_height)
155 ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
156 (*cinfo->master->finish_pass) (cinfo);
157 } else if (cinfo->global_state != CSTATE_WRCOEFS)
158 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
159 /* Perform any remaining passes */
160 while (! cinfo->master->is_last_pass) {
161 (*cinfo->master->prepare_for_pass) (cinfo);
162 for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
163 if (cinfo->progress != NULL) {
164 cinfo->progress->pass_counter = (long) iMCU_row;
165 cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;
166 (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
167 }
168 /* We bypass the main controller and invoke coef controller directly;
169 * all work is being done from the coefficient buffer.
170 */
171 if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))
172 ERREXIT(cinfo, JERR_CANT_SUSPEND);
173 }
174 (*cinfo->master->finish_pass) (cinfo);
175 }
176 /* Write EOI, do final cleanup */
177 (*cinfo->marker->write_file_trailer) (cinfo);
178 (*cinfo->dest->term_destination) (cinfo);
179 /* We can use jpeg_abort to release memory and reset global_state */
180 jpeg_abort((j_common_ptr) cinfo);
181 }
182
183
184 /*
185 * Write a special marker.
186 * This is only recommended for writing COM or APPn markers.
187 * Must be called after jpeg_start_compress() and before
188 * first call to jpeg_write_scanlines() or jpeg_write_raw_data().
189 */
190
191 GLOBAL(void)
192 jpeg_write_marker (j_compress_ptr cinfo, int marker,
193 const JOCTET *dataptr, unsigned int datalen)
194 {
195 JMETHOD(void, write_marker_byte, (j_compress_ptr info, int val));
196
197 if (cinfo->next_scanline != 0 ||
198 (cinfo->global_state != CSTATE_SCANNING &&
199 cinfo->global_state != CSTATE_RAW_OK &&
200 cinfo->global_state != CSTATE_WRCOEFS))
201 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
202
203 (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
204 write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
205 while (datalen--) {
206 (*write_marker_byte) (cinfo, *dataptr);
207 dataptr++;
208 }
209 }
210
211 /* Same, but piecemeal. */
212
213 GLOBAL(void)
214 jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
215 {
216 if (cinfo->next_scanline != 0 ||
217 (cinfo->global_state != CSTATE_SCANNING &&
218 cinfo->global_state != CSTATE_RAW_OK &&
219 cinfo->global_state != CSTATE_WRCOEFS))
220 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
221
222 (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
223 }
224
225 GLOBAL(void)
226 jpeg_write_m_byte (j_compress_ptr cinfo, int val)
227 {
228 (*cinfo->marker->write_marker_byte) (cinfo, val);
229 }
230
231
232 /*
233 * Alternate compression function: just write an abbreviated table file.
234 * Before calling this, all parameters and a data destination must be set up.
235 *
236 * To produce a pair of files containing abbreviated tables and abbreviated
237 * image data, one would proceed as follows:
238 *
239 * initialize JPEG object
240 * set JPEG parameters
241 * set destination to table file
242 * jpeg_write_tables(cinfo);
243 * set destination to image file
244 * jpeg_start_compress(cinfo, FALSE);
245 * write data...
246 * jpeg_finish_compress(cinfo);
247 *
248 * jpeg_write_tables has the side effect of marking all tables written
249 * (same as jpeg_suppress_tables(..., TRUE)). Thus a subsequent start_compress
250 * will not re-emit the tables unless it is passed write_all_tables=TRUE.
251 */
252
253 GLOBAL(void)
254 jpeg_write_tables (j_compress_ptr cinfo)
255 {
256 if (cinfo->global_state != CSTATE_START)
257 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
258
259 /* (Re)initialize error mgr and destination modules */
260 (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
261 (*cinfo->dest->init_destination) (cinfo);
262 /* Initialize the marker writer ... bit of a crock to do it here. */
263 jinit_marker_writer(cinfo);
264 /* Write them tables! */
265 (*cinfo->marker->write_tables_only) (cinfo);
266 /* And clean up. */
267 (*cinfo->dest->term_destination) (cinfo);
268 /*
269 * In library releases up through v6a, we called jpeg_abort() here to free
270 * any working memory allocated by the destination manager and marker
271 * writer. Some applications had a problem with that: they allocated space
272 * of their own from the library memory manager, and didn't want it to go
273 * away during write_tables. So now we do nothing. This will cause a
274 * memory leak if an app calls write_tables repeatedly without doing a full
275 * compression cycle or otherwise resetting the JPEG object. However, that
276 * seems less bad than unexpectedly freeing memory in the normal case.
277 * An app that prefers the old behavior can call jpeg_abort for itself after
278 * each call to jpeg_write_tables().
279 */
280 }
suppress
boolean suppress
Definition: jpeglib.h:931
jpeg_finish_compress
jpeg_finish_compress(j_compress_ptr cinfo)
Definition: jcapimin.c:147
CSTATE_START
#define CSTATE_START
Definition: jpegint.h:25
NUM_QUANT_TBLS
#define NUM_QUANT_TBLS
Definition: jpeglib.h:43
j_common_ptr
struct jpeg_common_struct * j_common_ptr
Definition: jpeglib.h:261
jpeg_destroy_compress
jpeg_destroy_compress(j_compress_ptr cinfo)
Definition: jcapimin.c:88
version
int version
Definition: jpeglib.h:901
NUM_HUFF_TBLS
#define NUM_HUFF_TBLS
Definition: jpeglib.h:44
JQUANT_TBL::sent_table
boolean sent_table
Definition: jpeglib.h:94
JQUANT_TBL
Definition: jpeglib.h:83
jpeg_error_mgr
Definition: jpeglib.h:643
ERREXIT
#define ERREXIT(cinfo, code)
Definition: jerror.h:205
jpeg_CreateCompress
jpeg_CreateCompress(j_compress_ptr cinfo, int version, size_t structsize)
Definition: jcapimin.c:30
jpeg_common_struct
Definition: jpeglib.h:253
SIZEOF
#define SIZEOF(object)
Definition: jinclude.h:80
datalen
int const JOCTET unsigned int datalen
Definition: jpeglib.h:950
CSTATE_RAW_OK
#define CSTATE_RAW_OK
Definition: jpegint.h:27
CSTATE_SCANNING
#define CSTATE_SCANNING
Definition: jpegint.h:26
jpeg_suppress_tables
jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress)
Definition: jcapimin.c:119
write_marker_byte
write_marker_byte(j_compress_ptr cinfo, int val)
Definition: jcmarker.c:450
marker
int marker
Definition: jpeglib.h:950
FALSE
#define FALSE
Definition: twiddle.c:37
jpeg_abort
jpeg_abort(j_common_ptr cinfo)
Definition: jcomapi.c:29
jpeg_write_marker
jpeg_write_marker(j_compress_ptr cinfo, int marker, const JOCTET *dataptr, unsigned int datalen)
Definition: jcapimin.c:192
JPEG_LIB_VERSION
#define JPEG_LIB_VERSION
Definition: jpeglib.h:33
jinit_memory_mgr
jinit_memory_mgr(j_common_ptr cinfo)
Definition: jmemmgr.c:1028
JMETHOD
#define JMETHOD(type, methodname, arglist)
Definition: jmorecfg.h:202
val
int val
Definition: jpeglib.h:956
structsize
int size_t structsize
Definition: jpeglib.h:901
jinclude.h
JSAMPIMAGE
JSAMPARRAY * JSAMPIMAGE
Definition: jpeglib.h:68
jpeg_error_mgr::i
int i[8]
Definition: jpeglib.h:662
ERREXIT1
#define ERREXIT1(cinfo, code, p1)
Definition: jerror.h:208
jpeg_compress_struct
Definition: jpeglib.h:268
JHUFF_TBL::sent_table
boolean sent_table
Definition: jpeglib.h:110
jpeg_abort_compress
jpeg_abort_compress(j_compress_ptr cinfo)
Definition: jcapimin.c:100
GLOBAL
#define GLOBAL(type)
Definition: jmorecfg.h:188
info
backing_store_ptr info
Definition: jmemsys.h:181
jinit_marker_writer
jinit_marker_writer(j_compress_ptr cinfo)
Definition: jcmarker.c:645
jpeg_write_m_byte
jpeg_write_m_byte(j_compress_ptr cinfo, int val)
Definition: jcapimin.c:226
jpeg_write_m_header
jpeg_write_m_header(j_compress_ptr cinfo, int marker, unsigned int datalen)
Definition: jcapimin.c:214
JDIMENSION
unsigned int JDIMENSION
Definition: jmorecfg.h:171
htbl
JHUFF_TBL * htbl
Definition: jchuff.h:47
dataptr
int const JOCTET * dataptr
Definition: jpeglib.h:950
const
#define const
Definition: zconf.h:196
JOCTET
char JOCTET
Definition: jmorecfg.h:115
jpeg_write_tables
jpeg_write_tables(j_compress_ptr cinfo)
Definition: jcapimin.c:254
jpeg_destroy
jpeg_destroy(j_common_ptr cinfo)
Definition: jcomapi.c:69
JHUFF_TBL
Definition: jpeglib.h:100
CSTATE_WRCOEFS
#define CSTATE_WRCOEFS
Definition: jpegint.h:28
ERREXIT2
#define ERREXIT2(cinfo, code, p1, p2)
Definition: jerror.h:212
jpeglib.h
MEMZERO
#define MEMZERO(target, size)
Definition: jinclude.h:67