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