Line data Source code
1 : /*
2 : * jcapimin.c
3 : *
4 : * This file was part of the Independent JPEG Group's software:
5 : * Copyright (C) 1994-1998, Thomas G. Lane.
6 : * Modified 2003-2010 by Guido Vollbeding.
7 : * It was modified by The libjpeg-turbo Project to include only code relevant
8 : * to libjpeg-turbo.
9 : * For conditions of distribution and use, see the accompanying README.ijg
10 : * file.
11 : *
12 : * This file contains application interface code for the compression half
13 : * of the JPEG library. These are the "minimum" API routines that may be
14 : * needed in either the normal full-compression case or the transcoding-only
15 : * case.
16 : *
17 : * Most of the routines intended to be called directly by an application
18 : * are in this file or in jcapistd.c. But also see jcparam.c for
19 : * parameter-setup helper routines, jcomapi.c for routines shared by
20 : * compression and decompression, and jctrans.c for the transcoding case.
21 : */
22 :
23 : #define JPEG_INTERNALS
24 : #include "jinclude.h"
25 : #include "jpeglib.h"
26 :
27 :
28 : /*
29 : * Initialization of a JPEG compression object.
30 : * The error manager must already be set up (in case memory manager fails).
31 : */
32 :
33 : GLOBAL(void)
34 0 : jpeg_CreateCompress (j_compress_ptr cinfo, int version, size_t structsize)
35 : {
36 : int i;
37 :
38 : /* Guard against version mismatches between library and caller. */
39 0 : cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */
40 0 : if (version != JPEG_LIB_VERSION)
41 0 : ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
42 0 : if (structsize != sizeof(struct jpeg_compress_struct))
43 0 : ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE,
44 : (int) sizeof(struct jpeg_compress_struct), (int) structsize);
45 :
46 : /* For debugging purposes, we zero the whole master structure.
47 : * But the application has already set the err pointer, and may have set
48 : * client_data, so we have to save and restore those fields.
49 : * Note: if application hasn't set client_data, tools like Purify may
50 : * complain here.
51 : */
52 : {
53 0 : struct jpeg_error_mgr *err = cinfo->err;
54 0 : void *client_data = cinfo->client_data; /* ignore Purify complaint here */
55 0 : MEMZERO(cinfo, sizeof(struct jpeg_compress_struct));
56 0 : cinfo->err = err;
57 0 : cinfo->client_data = client_data;
58 : }
59 0 : cinfo->is_decompressor = FALSE;
60 :
61 : /* Initialize a memory manager instance for this object */
62 0 : jinit_memory_mgr((j_common_ptr) cinfo);
63 :
64 : /* Zero out pointers to permanent structures. */
65 0 : cinfo->progress = NULL;
66 0 : cinfo->dest = NULL;
67 :
68 0 : cinfo->comp_info = NULL;
69 :
70 0 : for (i = 0; i < NUM_QUANT_TBLS; i++) {
71 0 : cinfo->quant_tbl_ptrs[i] = NULL;
72 : #if JPEG_LIB_VERSION >= 70
73 : cinfo->q_scale_factor[i] = 100;
74 : #endif
75 : }
76 :
77 0 : for (i = 0; i < NUM_HUFF_TBLS; i++) {
78 0 : cinfo->dc_huff_tbl_ptrs[i] = NULL;
79 0 : cinfo->ac_huff_tbl_ptrs[i] = NULL;
80 : }
81 :
82 : #if JPEG_LIB_VERSION >= 80
83 : /* Must do it here for emit_dqt in case jpeg_write_tables is used */
84 : cinfo->block_size = DCTSIZE;
85 : cinfo->natural_order = jpeg_natural_order;
86 : cinfo->lim_Se = DCTSIZE2-1;
87 : #endif
88 :
89 0 : cinfo->script_space = NULL;
90 :
91 0 : cinfo->input_gamma = 1.0; /* in case application forgets */
92 :
93 : /* OK, I'm ready */
94 0 : cinfo->global_state = CSTATE_START;
95 0 : }
96 :
97 :
98 : /*
99 : * Destruction of a JPEG compression object
100 : */
101 :
102 : GLOBAL(void)
103 0 : jpeg_destroy_compress (j_compress_ptr cinfo)
104 : {
105 0 : jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
106 0 : }
107 :
108 :
109 : /*
110 : * Abort processing of a JPEG compression operation,
111 : * but don't destroy the object itself.
112 : */
113 :
114 : GLOBAL(void)
115 0 : jpeg_abort_compress (j_compress_ptr cinfo)
116 : {
117 0 : jpeg_abort((j_common_ptr) cinfo); /* use common routine */
118 0 : }
119 :
120 :
121 : /*
122 : * Forcibly suppress or un-suppress all quantization and Huffman tables.
123 : * Marks all currently defined tables as already written (if suppress)
124 : * or not written (if !suppress). This will control whether they get emitted
125 : * by a subsequent jpeg_start_compress call.
126 : *
127 : * This routine is exported for use by applications that want to produce
128 : * abbreviated JPEG datastreams. It logically belongs in jcparam.c, but
129 : * since it is called by jpeg_start_compress, we put it here --- otherwise
130 : * jcparam.o would be linked whether the application used it or not.
131 : */
132 :
133 : GLOBAL(void)
134 0 : jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)
135 : {
136 : int i;
137 : JQUANT_TBL *qtbl;
138 : JHUFF_TBL *htbl;
139 :
140 0 : for (i = 0; i < NUM_QUANT_TBLS; i++) {
141 0 : if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
142 0 : qtbl->sent_table = suppress;
143 : }
144 :
145 0 : for (i = 0; i < NUM_HUFF_TBLS; i++) {
146 0 : if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
147 0 : htbl->sent_table = suppress;
148 0 : if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
149 0 : htbl->sent_table = suppress;
150 : }
151 0 : }
152 :
153 :
154 : /*
155 : * Finish JPEG compression.
156 : *
157 : * If a multipass operating mode was selected, this may do a great deal of
158 : * work including most of the actual output.
159 : */
160 :
161 : GLOBAL(void)
162 0 : jpeg_finish_compress (j_compress_ptr cinfo)
163 : {
164 : JDIMENSION iMCU_row;
165 :
166 0 : if (cinfo->global_state == CSTATE_SCANNING ||
167 0 : cinfo->global_state == CSTATE_RAW_OK) {
168 : /* Terminate first pass */
169 0 : if (cinfo->next_scanline < cinfo->image_height)
170 0 : ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
171 0 : (*cinfo->master->finish_pass) (cinfo);
172 0 : } else if (cinfo->global_state != CSTATE_WRCOEFS)
173 0 : ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
174 : /* Perform any remaining passes */
175 0 : while (! cinfo->master->is_last_pass) {
176 0 : (*cinfo->master->prepare_for_pass) (cinfo);
177 0 : for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
178 0 : if (cinfo->progress != NULL) {
179 0 : cinfo->progress->pass_counter = (long) iMCU_row;
180 0 : cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;
181 0 : (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
182 : }
183 : /* We bypass the main controller and invoke coef controller directly;
184 : * all work is being done from the coefficient buffer.
185 : */
186 0 : if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))
187 0 : ERREXIT(cinfo, JERR_CANT_SUSPEND);
188 : }
189 0 : (*cinfo->master->finish_pass) (cinfo);
190 : }
191 : /* Write EOI, do final cleanup */
192 0 : (*cinfo->marker->write_file_trailer) (cinfo);
193 0 : (*cinfo->dest->term_destination) (cinfo);
194 : /* We can use jpeg_abort to release memory and reset global_state */
195 0 : jpeg_abort((j_common_ptr) cinfo);
196 0 : }
197 :
198 :
199 : /*
200 : * Write a special marker.
201 : * This is only recommended for writing COM or APPn markers.
202 : * Must be called after jpeg_start_compress() and before
203 : * first call to jpeg_write_scanlines() or jpeg_write_raw_data().
204 : */
205 :
206 : GLOBAL(void)
207 0 : jpeg_write_marker (j_compress_ptr cinfo, int marker,
208 : const JOCTET *dataptr, unsigned int datalen)
209 : {
210 : void (*write_marker_byte) (j_compress_ptr info, int val);
211 :
212 0 : if (cinfo->next_scanline != 0 ||
213 0 : (cinfo->global_state != CSTATE_SCANNING &&
214 0 : cinfo->global_state != CSTATE_RAW_OK &&
215 0 : cinfo->global_state != CSTATE_WRCOEFS))
216 0 : ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
217 :
218 0 : (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
219 0 : write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
220 0 : while (datalen--) {
221 0 : (*write_marker_byte) (cinfo, *dataptr);
222 0 : dataptr++;
223 : }
224 0 : }
225 :
226 : /* Same, but piecemeal. */
227 :
228 : GLOBAL(void)
229 0 : jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
230 : {
231 0 : if (cinfo->next_scanline != 0 ||
232 0 : (cinfo->global_state != CSTATE_SCANNING &&
233 0 : cinfo->global_state != CSTATE_RAW_OK &&
234 0 : cinfo->global_state != CSTATE_WRCOEFS))
235 0 : ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
236 :
237 0 : (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
238 0 : }
239 :
240 : GLOBAL(void)
241 0 : jpeg_write_m_byte (j_compress_ptr cinfo, int val)
242 : {
243 0 : (*cinfo->marker->write_marker_byte) (cinfo, val);
244 0 : }
245 :
246 :
247 : /*
248 : * Alternate compression function: just write an abbreviated table file.
249 : * Before calling this, all parameters and a data destination must be set up.
250 : *
251 : * To produce a pair of files containing abbreviated tables and abbreviated
252 : * image data, one would proceed as follows:
253 : *
254 : * initialize JPEG object
255 : * set JPEG parameters
256 : * set destination to table file
257 : * jpeg_write_tables(cinfo);
258 : * set destination to image file
259 : * jpeg_start_compress(cinfo, FALSE);
260 : * write data...
261 : * jpeg_finish_compress(cinfo);
262 : *
263 : * jpeg_write_tables has the side effect of marking all tables written
264 : * (same as jpeg_suppress_tables(..., TRUE)). Thus a subsequent start_compress
265 : * will not re-emit the tables unless it is passed write_all_tables=TRUE.
266 : */
267 :
268 : GLOBAL(void)
269 0 : jpeg_write_tables (j_compress_ptr cinfo)
270 : {
271 0 : if (cinfo->global_state != CSTATE_START)
272 0 : ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
273 :
274 : /* (Re)initialize error mgr and destination modules */
275 0 : (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
276 0 : (*cinfo->dest->init_destination) (cinfo);
277 : /* Initialize the marker writer ... bit of a crock to do it here. */
278 0 : jinit_marker_writer(cinfo);
279 : /* Write them tables! */
280 0 : (*cinfo->marker->write_tables_only) (cinfo);
281 : /* And clean up. */
282 0 : (*cinfo->dest->term_destination) (cinfo);
283 : /*
284 : * In library releases up through v6a, we called jpeg_abort() here to free
285 : * any working memory allocated by the destination manager and marker
286 : * writer. Some applications had a problem with that: they allocated space
287 : * of their own from the library memory manager, and didn't want it to go
288 : * away during write_tables. So now we do nothing. This will cause a
289 : * memory leak if an app calls write_tables repeatedly without doing a full
290 : * compression cycle or otherwise resetting the JPEG object. However, that
291 : * seems less bad than unexpectedly freeing memory in the normal case.
292 : * An app that prefers the old behavior can call jpeg_abort for itself after
293 : * each call to jpeg_write_tables().
294 : */
295 0 : }
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