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)
jpeg_CreateCompress(j_compress_ptr cinfo,int version,size_t structsize)34 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 cinfo->mem = NULL; /* so jpeg_destroy knows mem mgr not called */
40 if (version != JPEG_LIB_VERSION)
41 ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
42 if (structsize != sizeof(struct jpeg_compress_struct))
43 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 struct jpeg_error_mgr *err = cinfo->err;
54 void *client_data = cinfo->client_data; /* ignore Purify complaint here */
55 MEMZERO(cinfo, sizeof(struct jpeg_compress_struct));
56 cinfo->err = err;
57 cinfo->client_data = client_data;
58 }
59 cinfo->is_decompressor = FALSE;
60
61 /* Initialize a memory manager instance for this object */
62 jinit_memory_mgr((j_common_ptr) cinfo);
63
64 /* Zero out pointers to permanent structures. */
65 cinfo->progress = NULL;
66 cinfo->dest = NULL;
67
68 cinfo->comp_info = NULL;
69
70 for (i = 0; i < NUM_QUANT_TBLS; i++) {
71 cinfo->quant_tbl_ptrs[i] = NULL;
72 #if JPEG_LIB_VERSION >= 70
73 cinfo->q_scale_factor[i] = 100;
74 #endif
75 }
76
77 for (i = 0; i < NUM_HUFF_TBLS; i++) {
78 cinfo->dc_huff_tbl_ptrs[i] = NULL;
79 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 cinfo->script_space = NULL;
90
91 cinfo->input_gamma = 1.0; /* in case application forgets */
92
93 /* OK, I'm ready */
94 cinfo->global_state = CSTATE_START;
95 }
96
97
98 /*
99 * Destruction of a JPEG compression object
100 */
101
102 GLOBAL(void)
jpeg_destroy_compress(j_compress_ptr cinfo)103 jpeg_destroy_compress (j_compress_ptr cinfo)
104 {
105 jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
106 }
107
108
109 /*
110 * Abort processing of a JPEG compression operation,
111 * but don't destroy the object itself.
112 */
113
114 GLOBAL(void)
jpeg_abort_compress(j_compress_ptr cinfo)115 jpeg_abort_compress (j_compress_ptr cinfo)
116 {
117 jpeg_abort((j_common_ptr) cinfo); /* use common routine */
118 }
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)
jpeg_suppress_tables(j_compress_ptr cinfo,boolean suppress)134 jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)
135 {
136 int i;
137 JQUANT_TBL *qtbl;
138 JHUFF_TBL *htbl;
139
140 for (i = 0; i < NUM_QUANT_TBLS; i++) {
141 if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
142 qtbl->sent_table = suppress;
143 }
144
145 for (i = 0; i < NUM_HUFF_TBLS; i++) {
146 if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
147 htbl->sent_table = suppress;
148 if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
149 htbl->sent_table = suppress;
150 }
151 }
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)
jpeg_finish_compress(j_compress_ptr cinfo)162 jpeg_finish_compress (j_compress_ptr cinfo)
163 {
164 JDIMENSION iMCU_row;
165
166 if (cinfo->global_state == CSTATE_SCANNING ||
167 cinfo->global_state == CSTATE_RAW_OK) {
168 /* Terminate first pass */
169 if (cinfo->next_scanline < cinfo->image_height)
170 ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
171 (*cinfo->master->finish_pass) (cinfo);
172 } else if (cinfo->global_state != CSTATE_WRCOEFS)
173 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
174 /* Perform any remaining passes */
175 while (! cinfo->master->is_last_pass) {
176 (*cinfo->master->prepare_for_pass) (cinfo);
177 for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
178 if (cinfo->progress != NULL) {
179 cinfo->progress->pass_counter = (long) iMCU_row;
180 cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;
181 (*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 if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))
187 ERREXIT(cinfo, JERR_CANT_SUSPEND);
188 }
189 (*cinfo->master->finish_pass) (cinfo);
190 }
191 /* Write EOI, do final cleanup */
192 (*cinfo->marker->write_file_trailer) (cinfo);
193 (*cinfo->dest->term_destination) (cinfo);
194 /* We can use jpeg_abort to release memory and reset global_state */
195 jpeg_abort((j_common_ptr) cinfo);
196 }
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)
jpeg_write_marker(j_compress_ptr cinfo,int marker,const JOCTET * dataptr,unsigned int datalen)207 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 if (cinfo->next_scanline != 0 ||
213 (cinfo->global_state != CSTATE_SCANNING &&
214 cinfo->global_state != CSTATE_RAW_OK &&
215 cinfo->global_state != CSTATE_WRCOEFS))
216 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
217
218 (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
219 write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
220 while (datalen--) {
221 (*write_marker_byte) (cinfo, *dataptr);
222 dataptr++;
223 }
224 }
225
226 /* Same, but piecemeal. */
227
228 GLOBAL(void)
jpeg_write_m_header(j_compress_ptr cinfo,int marker,unsigned int datalen)229 jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
230 {
231 if (cinfo->next_scanline != 0 ||
232 (cinfo->global_state != CSTATE_SCANNING &&
233 cinfo->global_state != CSTATE_RAW_OK &&
234 cinfo->global_state != CSTATE_WRCOEFS))
235 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
236
237 (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
238 }
239
240 GLOBAL(void)
jpeg_write_m_byte(j_compress_ptr cinfo,int val)241 jpeg_write_m_byte (j_compress_ptr cinfo, int val)
242 {
243 (*cinfo->marker->write_marker_byte) (cinfo, val);
244 }
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)
jpeg_write_tables(j_compress_ptr cinfo)269 jpeg_write_tables (j_compress_ptr cinfo)
270 {
271 if (cinfo->global_state != CSTATE_START)
272 ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
273
274 /* (Re)initialize error mgr and destination modules */
275 (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
276 (*cinfo->dest->init_destination) (cinfo);
277 /* Initialize the marker writer ... bit of a crock to do it here. */
278 jinit_marker_writer(cinfo);
279 /* Write them tables! */
280 (*cinfo->marker->write_tables_only) (cinfo);
281 /* And clean up. */
282 (*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 }
296