source: rtems-graphics-toolkit/jpeg-8d/jdapimin.c @ 86b99f7

Last change on this file since 86b99f7 was 86b99f7, checked in by Alexandru-Sever Horin <alex.sever.h@…>, on Aug 1, 2012 at 10:40:32 PM

Added jpeg-8d version. Made modifications to compile for RTEMS, without man or binaries

  • Property mode set to 100644
File size: 12.4 KB
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1/*
2 * jdapimin.c
3 *
4 * Copyright (C) 1994-1998, Thomas G. Lane.
5 * Modified 2009 by Guido Vollbeding.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
8 *
9 * This file contains application interface code for the decompression half
10 * of the JPEG library.  These are the "minimum" API routines that may be
11 * needed in either the normal full-decompression case or the
12 * transcoding-only case.
13 *
14 * Most of the routines intended to be called directly by an application
15 * are in this file or in jdapistd.c.  But also see jcomapi.c for routines
16 * shared by compression and decompression, and jdtrans.c for the transcoding
17 * case.
18 */
19
20#define JPEG_INTERNALS
21#include "jinclude.h"
22#include "jpeglib.h"
23
24
25/*
26 * Initialization of a JPEG decompression object.
27 * The error manager must already be set up (in case memory manager fails).
28 */
29
30GLOBAL(void)
31jpeg_CreateDecompress (j_decompress_ptr cinfo, int version, size_t structsize)
32{
33  int i;
34
35  /* Guard against version mismatches between library and caller. */
36  cinfo->mem = NULL;            /* so jpeg_destroy knows mem mgr not called */
37  if (version != JPEG_LIB_VERSION)
38    ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
39  if (structsize != SIZEOF(struct jpeg_decompress_struct))
40    ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, 
41             (int) SIZEOF(struct jpeg_decompress_struct), (int) structsize);
42
43  /* For debugging purposes, we zero the whole master structure.
44   * But the application has already set the err pointer, and may have set
45   * client_data, so we have to save and restore those fields.
46   * Note: if application hasn't set client_data, tools like Purify may
47   * complain here.
48   */
49  {
50    struct jpeg_error_mgr * err = cinfo->err;
51    void * client_data = cinfo->client_data; /* ignore Purify complaint here */
52    MEMZERO(cinfo, SIZEOF(struct jpeg_decompress_struct));
53    cinfo->err = err;
54    cinfo->client_data = client_data;
55  }
56  cinfo->is_decompressor = TRUE;
57
58  /* Initialize a memory manager instance for this object */
59  jinit_memory_mgr((j_common_ptr) cinfo);
60
61  /* Zero out pointers to permanent structures. */
62  cinfo->progress = NULL;
63  cinfo->src = NULL;
64
65  for (i = 0; i < NUM_QUANT_TBLS; i++)
66    cinfo->quant_tbl_ptrs[i] = NULL;
67
68  for (i = 0; i < NUM_HUFF_TBLS; i++) {
69    cinfo->dc_huff_tbl_ptrs[i] = NULL;
70    cinfo->ac_huff_tbl_ptrs[i] = NULL;
71  }
72
73  /* Initialize marker processor so application can override methods
74   * for COM, APPn markers before calling jpeg_read_header.
75   */
76  cinfo->marker_list = NULL;
77  jinit_marker_reader(cinfo);
78
79  /* And initialize the overall input controller. */
80  jinit_input_controller(cinfo);
81
82  /* OK, I'm ready */
83  cinfo->global_state = DSTATE_START;
84}
85
86
87/*
88 * Destruction of a JPEG decompression object
89 */
90
91GLOBAL(void)
92jpeg_destroy_decompress (j_decompress_ptr cinfo)
93{
94  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
95}
96
97
98/*
99 * Abort processing of a JPEG decompression operation,
100 * but don't destroy the object itself.
101 */
102
103GLOBAL(void)
104jpeg_abort_decompress (j_decompress_ptr cinfo)
105{
106  jpeg_abort((j_common_ptr) cinfo); /* use common routine */
107}
108
109
110/*
111 * Set default decompression parameters.
112 */
113
114LOCAL(void)
115default_decompress_parms (j_decompress_ptr cinfo)
116{
117  /* Guess the input colorspace, and set output colorspace accordingly. */
118  /* (Wish JPEG committee had provided a real way to specify this...) */
119  /* Note application may override our guesses. */
120  switch (cinfo->num_components) {
121  case 1:
122    cinfo->jpeg_color_space = JCS_GRAYSCALE;
123    cinfo->out_color_space = JCS_GRAYSCALE;
124    break;
125   
126  case 3:
127    if (cinfo->saw_JFIF_marker) {
128      cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */
129    } else if (cinfo->saw_Adobe_marker) {
130      switch (cinfo->Adobe_transform) {
131      case 0:
132        cinfo->jpeg_color_space = JCS_RGB;
133        break;
134      case 1:
135        cinfo->jpeg_color_space = JCS_YCbCr;
136        break;
137      default:
138        WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
139        cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
140        break;
141      }
142    } else {
143      /* Saw no special markers, try to guess from the component IDs */
144      int cid0 = cinfo->comp_info[0].component_id;
145      int cid1 = cinfo->comp_info[1].component_id;
146      int cid2 = cinfo->comp_info[2].component_id;
147
148      if (cid0 == 1 && cid1 == 2 && cid2 == 3)
149        cinfo->jpeg_color_space = JCS_YCbCr; /* assume JFIF w/out marker */
150      else if (cid0 == 82 && cid1 == 71 && cid2 == 66)
151        cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */
152      else {
153        TRACEMS3(cinfo, 1, JTRC_UNKNOWN_IDS, cid0, cid1, cid2);
154        cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
155      }
156    }
157    /* Always guess RGB is proper output colorspace. */
158    cinfo->out_color_space = JCS_RGB;
159    break;
160   
161  case 4:
162    if (cinfo->saw_Adobe_marker) {
163      switch (cinfo->Adobe_transform) {
164      case 0:
165        cinfo->jpeg_color_space = JCS_CMYK;
166        break;
167      case 2:
168        cinfo->jpeg_color_space = JCS_YCCK;
169        break;
170      default:
171        WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
172        cinfo->jpeg_color_space = JCS_YCCK; /* assume it's YCCK */
173        break;
174      }
175    } else {
176      /* No special markers, assume straight CMYK. */
177      cinfo->jpeg_color_space = JCS_CMYK;
178    }
179    cinfo->out_color_space = JCS_CMYK;
180    break;
181   
182  default:
183    cinfo->jpeg_color_space = JCS_UNKNOWN;
184    cinfo->out_color_space = JCS_UNKNOWN;
185    break;
186  }
187
188  /* Set defaults for other decompression parameters. */
189  cinfo->scale_num = cinfo->block_size;         /* 1:1 scaling */
190  cinfo->scale_denom = cinfo->block_size;
191  cinfo->output_gamma = 1.0;
192  cinfo->buffered_image = FALSE;
193  cinfo->raw_data_out = FALSE;
194  cinfo->dct_method = JDCT_DEFAULT;
195  cinfo->do_fancy_upsampling = TRUE;
196  cinfo->do_block_smoothing = TRUE;
197  cinfo->quantize_colors = FALSE;
198  /* We set these in case application only sets quantize_colors. */
199  cinfo->dither_mode = JDITHER_FS;
200#ifdef QUANT_2PASS_SUPPORTED
201  cinfo->two_pass_quantize = TRUE;
202#else
203  cinfo->two_pass_quantize = FALSE;
204#endif
205  cinfo->desired_number_of_colors = 256;
206  cinfo->colormap = NULL;
207  /* Initialize for no mode change in buffered-image mode. */
208  cinfo->enable_1pass_quant = FALSE;
209  cinfo->enable_external_quant = FALSE;
210  cinfo->enable_2pass_quant = FALSE;
211}
212
213
214/*
215 * Decompression startup: read start of JPEG datastream to see what's there.
216 * Need only initialize JPEG object and supply a data source before calling.
217 *
218 * This routine will read as far as the first SOS marker (ie, actual start of
219 * compressed data), and will save all tables and parameters in the JPEG
220 * object.  It will also initialize the decompression parameters to default
221 * values, and finally return JPEG_HEADER_OK.  On return, the application may
222 * adjust the decompression parameters and then call jpeg_start_decompress.
223 * (Or, if the application only wanted to determine the image parameters,
224 * the data need not be decompressed.  In that case, call jpeg_abort or
225 * jpeg_destroy to release any temporary space.)
226 * If an abbreviated (tables only) datastream is presented, the routine will
227 * return JPEG_HEADER_TABLES_ONLY upon reaching EOI.  The application may then
228 * re-use the JPEG object to read the abbreviated image datastream(s).
229 * It is unnecessary (but OK) to call jpeg_abort in this case.
230 * The JPEG_SUSPENDED return code only occurs if the data source module
231 * requests suspension of the decompressor.  In this case the application
232 * should load more source data and then re-call jpeg_read_header to resume
233 * processing.
234 * If a non-suspending data source is used and require_image is TRUE, then the
235 * return code need not be inspected since only JPEG_HEADER_OK is possible.
236 *
237 * This routine is now just a front end to jpeg_consume_input, with some
238 * extra error checking.
239 */
240
241GLOBAL(int)
242jpeg_read_header (j_decompress_ptr cinfo, boolean require_image)
243{
244  int retcode;
245
246  if (cinfo->global_state != DSTATE_START &&
247      cinfo->global_state != DSTATE_INHEADER)
248    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
249
250  retcode = jpeg_consume_input(cinfo);
251
252  switch (retcode) {
253  case JPEG_REACHED_SOS:
254    retcode = JPEG_HEADER_OK;
255    break;
256  case JPEG_REACHED_EOI:
257    if (require_image)          /* Complain if application wanted an image */
258      ERREXIT(cinfo, JERR_NO_IMAGE);
259    /* Reset to start state; it would be safer to require the application to
260     * call jpeg_abort, but we can't change it now for compatibility reasons.
261     * A side effect is to free any temporary memory (there shouldn't be any).
262     */
263    jpeg_abort((j_common_ptr) cinfo); /* sets state = DSTATE_START */
264    retcode = JPEG_HEADER_TABLES_ONLY;
265    break;
266  case JPEG_SUSPENDED:
267    /* no work */
268    break;
269  }
270
271  return retcode;
272}
273
274
275/*
276 * Consume data in advance of what the decompressor requires.
277 * This can be called at any time once the decompressor object has
278 * been created and a data source has been set up.
279 *
280 * This routine is essentially a state machine that handles a couple
281 * of critical state-transition actions, namely initial setup and
282 * transition from header scanning to ready-for-start_decompress.
283 * All the actual input is done via the input controller's consume_input
284 * method.
285 */
286
287GLOBAL(int)
288jpeg_consume_input (j_decompress_ptr cinfo)
289{
290  int retcode = JPEG_SUSPENDED;
291
292  /* NB: every possible DSTATE value should be listed in this switch */
293  switch (cinfo->global_state) {
294  case DSTATE_START:
295    /* Start-of-datastream actions: reset appropriate modules */
296    (*cinfo->inputctl->reset_input_controller) (cinfo);
297    /* Initialize application's data source module */
298    (*cinfo->src->init_source) (cinfo);
299    cinfo->global_state = DSTATE_INHEADER;
300    /*FALLTHROUGH*/
301  case DSTATE_INHEADER:
302    retcode = (*cinfo->inputctl->consume_input) (cinfo);
303    if (retcode == JPEG_REACHED_SOS) { /* Found SOS, prepare to decompress */
304      /* Set up default parameters based on header data */
305      default_decompress_parms(cinfo);
306      /* Set global state: ready for start_decompress */
307      cinfo->global_state = DSTATE_READY;
308    }
309    break;
310  case DSTATE_READY:
311    /* Can't advance past first SOS until start_decompress is called */
312    retcode = JPEG_REACHED_SOS;
313    break;
314  case DSTATE_PRELOAD:
315  case DSTATE_PRESCAN:
316  case DSTATE_SCANNING:
317  case DSTATE_RAW_OK:
318  case DSTATE_BUFIMAGE:
319  case DSTATE_BUFPOST:
320  case DSTATE_STOPPING:
321    retcode = (*cinfo->inputctl->consume_input) (cinfo);
322    break;
323  default:
324    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
325  }
326  return retcode;
327}
328
329
330/*
331 * Have we finished reading the input file?
332 */
333
334GLOBAL(boolean)
335jpeg_input_complete (j_decompress_ptr cinfo)
336{
337  /* Check for valid jpeg object */
338  if (cinfo->global_state < DSTATE_START ||
339      cinfo->global_state > DSTATE_STOPPING)
340    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
341  return cinfo->inputctl->eoi_reached;
342}
343
344
345/*
346 * Is there more than one scan?
347 */
348
349GLOBAL(boolean)
350jpeg_has_multiple_scans (j_decompress_ptr cinfo)
351{
352  /* Only valid after jpeg_read_header completes */
353  if (cinfo->global_state < DSTATE_READY ||
354      cinfo->global_state > DSTATE_STOPPING)
355    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
356  return cinfo->inputctl->has_multiple_scans;
357}
358
359
360/*
361 * Finish JPEG decompression.
362 *
363 * This will normally just verify the file trailer and release temp storage.
364 *
365 * Returns FALSE if suspended.  The return value need be inspected only if
366 * a suspending data source is used.
367 */
368
369GLOBAL(boolean)
370jpeg_finish_decompress (j_decompress_ptr cinfo)
371{
372  if ((cinfo->global_state == DSTATE_SCANNING ||
373       cinfo->global_state == DSTATE_RAW_OK) && ! cinfo->buffered_image) {
374    /* Terminate final pass of non-buffered mode */
375    if (cinfo->output_scanline < cinfo->output_height)
376      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
377    (*cinfo->master->finish_output_pass) (cinfo);
378    cinfo->global_state = DSTATE_STOPPING;
379  } else if (cinfo->global_state == DSTATE_BUFIMAGE) {
380    /* Finishing after a buffered-image operation */
381    cinfo->global_state = DSTATE_STOPPING;
382  } else if (cinfo->global_state != DSTATE_STOPPING) {
383    /* STOPPING = repeat call after a suspension, anything else is error */
384    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
385  }
386  /* Read until EOI */
387  while (! cinfo->inputctl->eoi_reached) {
388    if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)
389      return FALSE;             /* Suspend, come back later */
390  }
391  /* Do final cleanup */
392  (*cinfo->src->term_source) (cinfo);
393  /* We can use jpeg_abort to release memory and reset global_state */
394  jpeg_abort((j_common_ptr) cinfo);
395  return TRUE;
396}
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