jdk

1
/*
2
 * reserved comment block
3
 * DO NOT REMOVE OR ALTER!
4
 */
5
/*
6
 * jcapimin.c
7
 *
8
 * Copyright (C) 1994-1998, Thomas G. Lane.
9
 * This file is part of the Independent JPEG Group's software.
10
 * For conditions of distribution and use, see the accompanying README 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

73
  for (i = 0; i < NUM_HUFF_TBLS; i++) {
74
    cinfo->dc_huff_tbl_ptrs[i] = NULL;
75
    cinfo->ac_huff_tbl_ptrs[i] = NULL;
76
  }
77

78
  cinfo->script_space = NULL;
79

80
  cinfo->input_gamma = 1.0;     /* in case application forgets */
81

82
  /* OK, I'm ready */
83
  cinfo->global_state = CSTATE_START;
84
}
85

86

87
/*
88
 * Destruction of a JPEG compression object
89
 */
90

91
GLOBAL(void)
92
jpeg_destroy_compress (j_compress_ptr cinfo)
93
{
94
  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
95
}
96

97

98
/*
99
 * Abort processing of a JPEG compression operation,
100
 * but don't destroy the object itself.
101
 */
102

103
GLOBAL(void)
104
jpeg_abort_compress (j_compress_ptr cinfo)
105
{
106
  jpeg_abort((j_common_ptr) cinfo); /* use common routine */
107
}
108

109

110
/*
111
 * Forcibly suppress or un-suppress all quantization and Huffman tables.
112
 * Marks all currently defined tables as already written (if suppress)
113
 * or not written (if !suppress).  This will control whether they get emitted
114
 * by a subsequent jpeg_start_compress call.
115
 *
116
 * This routine is exported for use by applications that want to produce
117
 * abbreviated JPEG datastreams.  It logically belongs in jcparam.c, but
118
 * since it is called by jpeg_start_compress, we put it here --- otherwise
119
 * jcparam.o would be linked whether the application used it or not.
120
 */
121

122
GLOBAL(void)
123
jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)
124
{
125
  int i;
126
  JQUANT_TBL * qtbl;
127
  JHUFF_TBL * htbl;
128

129
  for (i = 0; i < NUM_QUANT_TBLS; i++) {
130
    if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
131
      qtbl->sent_table = suppress;
132
  }
133

134
  for (i = 0; i < NUM_HUFF_TBLS; i++) {
135
    if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
136
      htbl->sent_table = suppress;
137
    if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
138
      htbl->sent_table = suppress;
139
  }
140
}
141

142

143
/*
144
 * Finish JPEG compression.
145
 *
146
 * If a multipass operating mode was selected, this may do a great deal of
147
 * work including most of the actual output.
148
 */
149

150
GLOBAL(void)
151
jpeg_finish_compress (j_compress_ptr cinfo)
152
{
153
  JDIMENSION iMCU_row;
154

155
  if (cinfo->global_state == CSTATE_SCANNING ||
156
      cinfo->global_state == CSTATE_RAW_OK) {
157
    /* Terminate first pass */
158
    if (cinfo->next_scanline < cinfo->image_height)
159
      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
160
    (*cinfo->master->finish_pass) (cinfo);
161
  } else if (cinfo->global_state != CSTATE_WRCOEFS)
162
    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
163
  /* Perform any remaining passes */
164
  while (! cinfo->master->is_last_pass) {
165
    (*cinfo->master->prepare_for_pass) (cinfo);
166
    for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
167
      if (cinfo->progress != NULL) {
168
        cinfo->progress->pass_counter = (long) iMCU_row;
169
        cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;
170
        (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
171
      }
172
      /* We bypass the main controller and invoke coef controller directly;
173
       * all work is being done from the coefficient buffer.
174
       */
175
      if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))
176
        ERREXIT(cinfo, JERR_CANT_SUSPEND);
177
    }
178
    (*cinfo->master->finish_pass) (cinfo);
179
  }
180
  /* Write EOI, do final cleanup */
181
  (*cinfo->marker->write_file_trailer) (cinfo);
182
  (*cinfo->dest->term_destination) (cinfo);
183
  /* We can use jpeg_abort to release memory and reset global_state */
184
  jpeg_abort((j_common_ptr) cinfo);
185
}
186

187

188
/*
189
 * Write a special marker.
190
 * This is only recommended for writing COM or APPn markers.
191
 * Must be called after jpeg_start_compress() and before
192
 * first call to jpeg_write_scanlines() or jpeg_write_raw_data().
193
 */
194

195
GLOBAL(void)
196
jpeg_write_marker (j_compress_ptr cinfo, int marker,
197
                   const JOCTET *dataptr, unsigned int datalen)
198
{
199
  JMETHOD(void, write_marker_byte, (j_compress_ptr info, int val));
200

201
  if (cinfo->next_scanline != 0 ||
202
      (cinfo->global_state != CSTATE_SCANNING &&
203
       cinfo->global_state != CSTATE_RAW_OK &&
204
       cinfo->global_state != CSTATE_WRCOEFS))
205
    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
206

207
  (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
208
  write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
209
  while (datalen--) {
210
    (*write_marker_byte) (cinfo, *dataptr);
211
    dataptr++;
212
  }
213
}
214

215
/* Same, but piecemeal. */
216

217
GLOBAL(void)
218
jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
219
{
220
  if (cinfo->next_scanline != 0 ||
221
      (cinfo->global_state != CSTATE_SCANNING &&
222
       cinfo->global_state != CSTATE_RAW_OK &&
223
       cinfo->global_state != CSTATE_WRCOEFS))
224
    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
225

226
  (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);
227
}
228

229
GLOBAL(void)
230
jpeg_write_m_byte (j_compress_ptr cinfo, int val)
231
{
232
  (*cinfo->marker->write_marker_byte) (cinfo, val);
233
}
234

235

236
/*
237
 * Alternate compression function: just write an abbreviated table file.
238
 * Before calling this, all parameters and a data destination must be set up.
239
 *
240
 * To produce a pair of files containing abbreviated tables and abbreviated
241
 * image data, one would proceed as follows:
242
 *
243
 *              initialize JPEG object
244
 *              set JPEG parameters
245
 *              set destination to table file
246
 *              jpeg_write_tables(cinfo);
247
 *              set destination to image file
248
 *              jpeg_start_compress(cinfo, FALSE);
249
 *              write data...
250
 *              jpeg_finish_compress(cinfo);
251
 *
252
 * jpeg_write_tables has the side effect of marking all tables written
253
 * (same as jpeg_suppress_tables(..., TRUE)).  Thus a subsequent start_compress
254
 * will not re-emit the tables unless it is passed write_all_tables=TRUE.
255
 */
256

257
GLOBAL(void)
258
jpeg_write_tables (j_compress_ptr cinfo)
259
{
260
  if (cinfo->global_state != CSTATE_START)
261
    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
262

263
  /* (Re)initialize error mgr and destination modules */
264
  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
265
  (*cinfo->dest->init_destination) (cinfo);
266
  /* Initialize the marker writer ... bit of a crock to do it here. */
267
  jinit_marker_writer(cinfo);
268
  /* Write them tables! */
269
  (*cinfo->marker->write_tables_only) (cinfo);
270
  /* And clean up. */
271
  (*cinfo->dest->term_destination) (cinfo);
272
  /*
273
   * In library releases up through v6a, we called jpeg_abort() here to free
274
   * any working memory allocated by the destination manager and marker
275
   * writer.  Some applications had a problem with that: they allocated space
276
   * of their own from the library memory manager, and didn't want it to go
277
   * away during write_tables.  So now we do nothing.  This will cause a
278
   * memory leak if an app calls write_tables repeatedly without doing a full
279
   * compression cycle or otherwise resetting the JPEG object.  However, that
280
   * seems less bad than unexpectedly freeing memory in the normal case.
281
   * An app that prefers the old behavior can call jpeg_abort for itself after
282
   * each call to jpeg_write_tables().
283
   */
284
}
285