Coverage Report

Created: 2024-05-04 12:45

/proc/self/cwd/external/libjpeg_turbo/jdinput.c
Line
Count
Source (jump to first uncovered line)
1
/*
2
 * jdinput.c
3
 *
4
 * This file was part of the Independent JPEG Group's software:
5
 * Copyright (C) 1991-1997, Thomas G. Lane.
6
 * libjpeg-turbo Modifications:
7
 * Copyright (C) 2010, 2016, 2018, 2022, D. R. Commander.
8
 * Copyright (C) 2015, Google, Inc.
9
 * For conditions of distribution and use, see the accompanying README.ijg
10
 * file.
11
 *
12
 * This file contains input control logic for the JPEG decompressor.
13
 * These routines are concerned with controlling the decompressor's input
14
 * processing (marker reading and coefficient decoding).  The actual input
15
 * reading is done in jdmarker.c, jdhuff.c, and jdphuff.c.
16
 */
17
18
#define JPEG_INTERNALS
19
#include "jinclude.h"
20
#include "jpeglib.h"
21
#include "jpegcomp.h"
22
23
24
/* Private state */
25
26
typedef struct {
27
  struct jpeg_input_controller pub; /* public fields */
28
29
  boolean inheaders;            /* TRUE until first SOS is reached */
30
} my_input_controller;
31
32
typedef my_input_controller *my_inputctl_ptr;
33
34
35
/* Forward declarations */
36
METHODDEF(int) consume_markers(j_decompress_ptr cinfo);
37
38
39
/*
40
 * Routines to calculate various quantities related to the size of the image.
41
 */
42
43
LOCAL(void)
44
initial_setup(j_decompress_ptr cinfo)
45
/* Called once, when first SOS marker is reached */
46
124
{
47
124
  int ci;
48
124
  jpeg_component_info *compptr;
49
50
  /* Make sure image isn't bigger than I can handle */
51
124
  if ((long)cinfo->image_height > (long)JPEG_MAX_DIMENSION ||
52
124
      (long)cinfo->image_width > (long)JPEG_MAX_DIMENSION)
53
0
    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int)JPEG_MAX_DIMENSION);
54
55
  /* For now, precision must match compiled-in value... */
56
124
  if (cinfo->data_precision != BITS_IN_JSAMPLE)
57
0
    ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
58
59
  /* Check that number of components won't exceed internal array sizes */
60
124
  if (cinfo->num_components > MAX_COMPONENTS)
61
0
    ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
62
124
             MAX_COMPONENTS);
63
64
  /* Compute maximum sampling factors; check factor validity */
65
124
  cinfo->max_h_samp_factor = 1;
66
124
  cinfo->max_v_samp_factor = 1;
67
459
  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
68
335
       ci++, compptr++) {
69
335
    if (compptr->h_samp_factor <= 0 ||
70
335
        compptr->h_samp_factor > MAX_SAMP_FACTOR ||
71
335
        compptr->v_samp_factor <= 0 ||
72
335
        compptr->v_samp_factor > MAX_SAMP_FACTOR)
73
0
      ERREXIT(cinfo, JERR_BAD_SAMPLING);
74
335
    cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
75
335
                                   compptr->h_samp_factor);
76
335
    cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
77
335
                                   compptr->v_samp_factor);
78
335
  }
79
80
#if JPEG_LIB_VERSION >= 80
81
  cinfo->block_size = DCTSIZE;
82
  cinfo->natural_order = jpeg_natural_order;
83
  cinfo->lim_Se = DCTSIZE2 - 1;
84
#endif
85
86
  /* We initialize DCT_scaled_size and min_DCT_scaled_size to DCTSIZE.
87
   * In the full decompressor, this will be overridden by jdmaster.c;
88
   * but in the transcoder, jdmaster.c is not used, so we must do it here.
89
   */
90
#if JPEG_LIB_VERSION >= 70
91
  cinfo->min_DCT_h_scaled_size = cinfo->min_DCT_v_scaled_size = DCTSIZE;
92
#else
93
124
  cinfo->min_DCT_scaled_size = DCTSIZE;
94
124
#endif
95
96
  /* Compute dimensions of components */
97
459
  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
98
335
       ci++, compptr++) {
99
#if JPEG_LIB_VERSION >= 70
100
    compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size = DCTSIZE;
101
#else
102
335
    compptr->DCT_scaled_size = DCTSIZE;
103
335
#endif
104
    /* Size in DCT blocks */
105
335
    compptr->width_in_blocks = (JDIMENSION)
106
335
      jdiv_round_up((long)cinfo->image_width * (long)compptr->h_samp_factor,
107
335
                    (long)(cinfo->max_h_samp_factor * DCTSIZE));
108
335
    compptr->height_in_blocks = (JDIMENSION)
109
335
      jdiv_round_up((long)cinfo->image_height * (long)compptr->v_samp_factor,
110
335
                    (long)(cinfo->max_v_samp_factor * DCTSIZE));
111
    /* Set the first and last MCU columns to decompress from multi-scan images.
112
     * By default, decompress all of the MCU columns.
113
     */
114
335
    cinfo->master->first_MCU_col[ci] = 0;
115
335
    cinfo->master->last_MCU_col[ci] = compptr->width_in_blocks - 1;
116
    /* downsampled_width and downsampled_height will also be overridden by
117
     * jdmaster.c if we are doing full decompression.  The transcoder library
118
     * doesn't use these values, but the calling application might.
119
     */
120
    /* Size in samples */
121
335
    compptr->downsampled_width = (JDIMENSION)
122
335
      jdiv_round_up((long)cinfo->image_width * (long)compptr->h_samp_factor,
123
335
                    (long)cinfo->max_h_samp_factor);
124
335
    compptr->downsampled_height = (JDIMENSION)
125
335
      jdiv_round_up((long)cinfo->image_height * (long)compptr->v_samp_factor,
126
335
                    (long)cinfo->max_v_samp_factor);
127
    /* Mark component needed, until color conversion says otherwise */
128
335
    compptr->component_needed = TRUE;
129
    /* Mark no quantization table yet saved for component */
130
335
    compptr->quant_table = NULL;
131
335
  }
132
133
  /* Compute number of fully interleaved MCU rows. */
134
124
  cinfo->total_iMCU_rows = (JDIMENSION)
135
124
    jdiv_round_up((long)cinfo->image_height,
136
124
                  (long)(cinfo->max_v_samp_factor * DCTSIZE));
137
138
  /* Decide whether file contains multiple scans */
139
124
  if (cinfo->comps_in_scan < cinfo->num_components || cinfo->progressive_mode)
140
91
    cinfo->inputctl->has_multiple_scans = TRUE;
141
33
  else
142
33
    cinfo->inputctl->has_multiple_scans = FALSE;
143
124
}
144
145
146
LOCAL(void)
147
per_scan_setup(j_decompress_ptr cinfo)
148
/* Do computations that are needed before processing a JPEG scan */
149
/* cinfo->comps_in_scan and cinfo->cur_comp_info[] were set from SOS marker */
150
3.91k
{
151
3.91k
  int ci, mcublks, tmp;
152
3.91k
  jpeg_component_info *compptr;
153
154
3.91k
  if (cinfo->comps_in_scan == 1) {
155
156
    /* Noninterleaved (single-component) scan */
157
2.34k
    compptr = cinfo->cur_comp_info[0];
158
159
    /* Overall image size in MCUs */
160
2.34k
    cinfo->MCUs_per_row = compptr->width_in_blocks;
161
2.34k
    cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
162
163
    /* For noninterleaved scan, always one block per MCU */
164
2.34k
    compptr->MCU_width = 1;
165
2.34k
    compptr->MCU_height = 1;
166
2.34k
    compptr->MCU_blocks = 1;
167
2.34k
    compptr->MCU_sample_width = compptr->_DCT_scaled_size;
168
2.34k
    compptr->last_col_width = 1;
169
    /* For noninterleaved scans, it is convenient to define last_row_height
170
     * as the number of block rows present in the last iMCU row.
171
     */
172
2.34k
    tmp = (int)(compptr->height_in_blocks % compptr->v_samp_factor);
173
2.34k
    if (tmp == 0) tmp = compptr->v_samp_factor;
174
2.34k
    compptr->last_row_height = tmp;
175
176
    /* Prepare array describing MCU composition */
177
2.34k
    cinfo->blocks_in_MCU = 1;
178
2.34k
    cinfo->MCU_membership[0] = 0;
179
180
2.34k
  } else {
181
182
    /* Interleaved (multi-component) scan */
183
1.56k
    if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
184
0
      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
185
1.56k
               MAX_COMPS_IN_SCAN);
186
187
    /* Overall image size in MCUs */
188
1.56k
    cinfo->MCUs_per_row = (JDIMENSION)
189
1.56k
      jdiv_round_up((long)cinfo->image_width,
190
1.56k
                    (long)(cinfo->max_h_samp_factor * DCTSIZE));
191
1.56k
    cinfo->MCU_rows_in_scan = (JDIMENSION)
192
1.56k
      jdiv_round_up((long)cinfo->image_height,
193
1.56k
                    (long)(cinfo->max_v_samp_factor * DCTSIZE));
194
195
1.56k
    cinfo->blocks_in_MCU = 0;
196
197
5.11k
    for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
198
3.54k
      compptr = cinfo->cur_comp_info[ci];
199
      /* Sampling factors give # of blocks of component in each MCU */
200
3.54k
      compptr->MCU_width = compptr->h_samp_factor;
201
3.54k
      compptr->MCU_height = compptr->v_samp_factor;
202
3.54k
      compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
203
3.54k
      compptr->MCU_sample_width = compptr->MCU_width *
204
3.54k
                                  compptr->_DCT_scaled_size;
205
      /* Figure number of non-dummy blocks in last MCU column & row */
206
3.54k
      tmp = (int)(compptr->width_in_blocks % compptr->MCU_width);
207
3.54k
      if (tmp == 0) tmp = compptr->MCU_width;
208
3.54k
      compptr->last_col_width = tmp;
209
3.54k
      tmp = (int)(compptr->height_in_blocks % compptr->MCU_height);
210
3.54k
      if (tmp == 0) tmp = compptr->MCU_height;
211
3.54k
      compptr->last_row_height = tmp;
212
      /* Prepare array describing MCU composition */
213
3.54k
      mcublks = compptr->MCU_blocks;
214
3.54k
      if (cinfo->blocks_in_MCU + mcublks > D_MAX_BLOCKS_IN_MCU)
215
0
        ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
216
14.3k
      while (mcublks-- > 0) {
217
10.8k
        cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
218
10.8k
      }
219
3.54k
    }
220
221
1.56k
  }
222
3.91k
}
223
224
225
/*
226
 * Save away a copy of the Q-table referenced by each component present
227
 * in the current scan, unless already saved during a prior scan.
228
 *
229
 * In a multiple-scan JPEG file, the encoder could assign different components
230
 * the same Q-table slot number, but change table definitions between scans
231
 * so that each component uses a different Q-table.  (The IJG encoder is not
232
 * currently capable of doing this, but other encoders might.)  Since we want
233
 * to be able to dequantize all the components at the end of the file, this
234
 * means that we have to save away the table actually used for each component.
235
 * We do this by copying the table at the start of the first scan containing
236
 * the component.
237
 * Rec. ITU-T T.81 | ISO/IEC 10918-1 prohibits the encoder from changing the
238
 * contents of a Q-table slot between scans of a component using that slot.  If
239
 * the encoder does so anyway, this decoder will simply use the Q-table values
240
 * that were current at the start of the first scan for the component.
241
 *
242
 * The decompressor output side looks only at the saved quant tables,
243
 * not at the current Q-table slots.
244
 */
245
246
LOCAL(void)
247
latch_quant_tables(j_decompress_ptr cinfo)
248
3.91k
{
249
3.91k
  int ci, qtblno;
250
3.91k
  jpeg_component_info *compptr;
251
3.91k
  JQUANT_TBL *qtbl;
252
253
9.79k
  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
254
5.88k
    compptr = cinfo->cur_comp_info[ci];
255
    /* No work if we already saved Q-table for this component */
256
5.88k
    if (compptr->quant_table != NULL)
257
5.68k
      continue;
258
    /* Make sure specified quantization table is present */
259
197
    qtblno = compptr->quant_tbl_no;
260
197
    if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
261
197
        cinfo->quant_tbl_ptrs[qtblno] == NULL)
262
1
      ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
263
    /* OK, save away the quantization table */
264
197
    qtbl = (JQUANT_TBL *)
265
197
      (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
266
197
                                  sizeof(JQUANT_TBL));
267
197
    memcpy(qtbl, cinfo->quant_tbl_ptrs[qtblno], sizeof(JQUANT_TBL));
268
197
    compptr->quant_table = qtbl;
269
197
  }
270
3.91k
}
271
272
273
/*
274
 * Initialize the input modules to read a scan of compressed data.
275
 * The first call to this is done by jdmaster.c after initializing
276
 * the entire decompressor (during jpeg_start_decompress).
277
 * Subsequent calls come from consume_markers, below.
278
 */
279
280
METHODDEF(void)
281
start_input_pass(j_decompress_ptr cinfo)
282
3.91k
{
283
3.91k
  per_scan_setup(cinfo);
284
3.91k
  latch_quant_tables(cinfo);
285
3.91k
  (*cinfo->entropy->start_pass) (cinfo);
286
3.91k
  (*cinfo->coef->start_input_pass) (cinfo);
287
3.91k
  cinfo->inputctl->consume_input = cinfo->coef->consume_data;
288
3.91k
}
289
290
291
/*
292
 * Finish up after inputting a compressed-data scan.
293
 * This is called by the coefficient controller after it's read all
294
 * the expected data of the scan.
295
 */
296
297
METHODDEF(void)
298
finish_input_pass(j_decompress_ptr cinfo)
299
3.89k
{
300
3.89k
  cinfo->inputctl->consume_input = consume_markers;
301
3.89k
}
302
303
304
/*
305
 * Read JPEG markers before, between, or after compressed-data scans.
306
 * Change state as necessary when a new scan is reached.
307
 * Return value is JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
308
 *
309
 * The consume_input method pointer points either here or to the
310
 * coefficient controller's consume_data routine, depending on whether
311
 * we are reading a compressed data segment or inter-segment markers.
312
 */
313
314
METHODDEF(int)
315
consume_markers(j_decompress_ptr cinfo)
316
7.49k
{
317
7.49k
  my_inputctl_ptr inputctl = (my_inputctl_ptr)cinfo->inputctl;
318
7.49k
  int val;
319
320
7.49k
  if (inputctl->pub.eoi_reached) /* After hitting EOI, read no further */
321
0
    return JPEG_REACHED_EOI;
322
323
7.49k
  val = (*cinfo->marker->read_markers) (cinfo);
324
325
7.49k
  switch (val) {
326
3.91k
  case JPEG_REACHED_SOS:        /* Found SOS */
327
3.91k
    if (inputctl->inheaders) {  /* 1st SOS */
328
124
      initial_setup(cinfo);
329
124
      inputctl->inheaders = FALSE;
330
      /* Note: start_input_pass must be called by jdmaster.c
331
       * before any more input can be consumed.  jdapimin.c is
332
       * responsible for enforcing this sequencing.
333
       */
334
3.78k
    } else {                    /* 2nd or later SOS marker */
335
3.78k
      if (!inputctl->pub.has_multiple_scans)
336
1
        ERREXIT(cinfo, JERR_EOI_EXPECTED); /* Oops, I wasn't expecting this! */
337
3.78k
      start_input_pass(cinfo);
338
3.78k
    }
339
3.91k
    break;
340
10
  case JPEG_REACHED_EOI:        /* Found EOI */
341
10
    inputctl->pub.eoi_reached = TRUE;
342
10
    if (inputctl->inheaders) {  /* Tables-only datastream, apparently */
343
9
      if (cinfo->marker->saw_SOF)
344
4
        ERREXIT(cinfo, JERR_SOF_NO_SOS);
345
9
    } else {
346
      /* Prevent infinite loop in coef ctlr's decompress_data routine
347
       * if user set output_scan_number larger than number of scans.
348
       */
349
1
      if (cinfo->output_scan_number > cinfo->input_scan_number)
350
0
        cinfo->output_scan_number = cinfo->input_scan_number;
351
1
    }
352
10
    break;
353
1.19k
  case JPEG_SUSPENDED:
354
1.19k
    break;
355
7.49k
  }
356
357
5.10k
  return val;
358
7.49k
}
359
360
361
/*
362
 * Reset state to begin a fresh datastream.
363
 */
364
365
METHODDEF(void)
366
reset_input_controller(j_decompress_ptr cinfo)
367
3.60k
{
368
3.60k
  my_inputctl_ptr inputctl = (my_inputctl_ptr)cinfo->inputctl;
369
370
3.60k
  inputctl->pub.consume_input = consume_markers;
371
3.60k
  inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */
372
3.60k
  inputctl->pub.eoi_reached = FALSE;
373
3.60k
  inputctl->inheaders = TRUE;
374
  /* Reset other modules */
375
3.60k
  (*cinfo->err->reset_error_mgr) ((j_common_ptr)cinfo);
376
3.60k
  (*cinfo->marker->reset_marker_reader) (cinfo);
377
  /* Reset progression state -- would be cleaner if entropy decoder did this */
378
3.60k
  cinfo->coef_bits = NULL;
379
3.60k
}
380
381
382
/*
383
 * Initialize the input controller module.
384
 * This is called only once, when the decompression object is created.
385
 */
386
387
GLOBAL(void)
388
jinit_input_controller(j_decompress_ptr cinfo)
389
3.60k
{
390
3.60k
  my_inputctl_ptr inputctl;
391
392
  /* Create subobject in permanent pool */
393
3.60k
  inputctl = (my_inputctl_ptr)
394
3.60k
    (*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_PERMANENT,
395
3.60k
                                sizeof(my_input_controller));
396
3.60k
  cinfo->inputctl = (struct jpeg_input_controller *)inputctl;
397
  /* Initialize method pointers */
398
3.60k
  inputctl->pub.consume_input = consume_markers;
399
3.60k
  inputctl->pub.reset_input_controller = reset_input_controller;
400
3.60k
  inputctl->pub.start_input_pass = start_input_pass;
401
3.60k
  inputctl->pub.finish_input_pass = finish_input_pass;
402
  /* Initialize state: can't use reset_input_controller since we don't
403
   * want to try to reset other modules yet.
404
   */
405
3.60k
  inputctl->pub.has_multiple_scans = FALSE; /* "unknown" would be better */
406
3.60k
  inputctl->pub.eoi_reached = FALSE;
407
3.60k
  inputctl->inheaders = TRUE;
408
3.60k
}