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 | 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) |
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) |
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) |
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) |
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) |
207 | jpeg_write_marker(j_compress_ptr cinfo, int marker, const JOCTET *dataptr, |
208 | 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) |
229 | (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) |
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) |
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 | |