ReactOS  0.4.15-dev-439-g292f67a
jdapistd.c
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1 /*
2  * jdapistd.c
3  *
4  * Copyright (C) 1994-1996, Thomas G. Lane.
5  * Modified 2002-2013 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 "standard" API routines that are
11  * used in the normal full-decompression case. They are not used by a
12  * transcoding-only application. Note that if an application links in
13  * jpeg_start_decompress, it will end up linking in the entire decompressor.
14  * We thus must separate this file from jdapimin.c to avoid linking the
15  * whole decompression library into a transcoder.
16  */
17 
18 #define JPEG_INTERNALS
19 #include "jinclude.h"
20 #include "jpeglib.h"
21 
22 
23 /* Forward declarations */
25 
26 
27 /*
28  * Decompression initialization.
29  * jpeg_read_header must be completed before calling this.
30  *
31  * If a multipass operating mode was selected, this will do all but the
32  * last pass, and thus may take a great deal of time.
33  *
34  * Returns FALSE if suspended. The return value need be inspected only if
35  * a suspending data source is used.
36  */
37 
38 GLOBAL(boolean)
39 jpeg_start_decompress (j_decompress_ptr cinfo)
40 {
41  if (cinfo->global_state == DSTATE_READY) {
42  /* First call: initialize master control, select active modules */
44  if (cinfo->buffered_image) {
45  /* No more work here; expecting jpeg_start_output next */
46  cinfo->global_state = DSTATE_BUFIMAGE;
47  return TRUE;
48  }
49  cinfo->global_state = DSTATE_PRELOAD;
50  }
51  if (cinfo->global_state == DSTATE_PRELOAD) {
52  /* If file has multiple scans, absorb them all into the coef buffer */
53  if (cinfo->inputctl->has_multiple_scans) {
54 #ifdef D_MULTISCAN_FILES_SUPPORTED
55  for (;;) {
56  int retcode;
57  /* Call progress monitor hook if present */
58  if (cinfo->progress != NULL)
59  (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
60  /* Absorb some more input */
61  retcode = (*cinfo->inputctl->consume_input) (cinfo);
62  if (retcode == JPEG_SUSPENDED)
63  return FALSE;
64  if (retcode == JPEG_REACHED_EOI)
65  break;
66  /* Advance progress counter if appropriate */
67  if (cinfo->progress != NULL &&
68  (retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) {
69  if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) {
70  /* jdmaster underestimated number of scans; ratchet up one scan */
71  cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows;
72  }
73  }
74  }
75 #else
76  ERREXIT(cinfo, JERR_NOT_COMPILED);
77 #endif /* D_MULTISCAN_FILES_SUPPORTED */
78  }
79  cinfo->output_scan_number = cinfo->input_scan_number;
80  } else if (cinfo->global_state != DSTATE_PRESCAN)
81  ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
82  /* Perform any dummy output passes, and set up for the final pass */
83  return output_pass_setup(cinfo);
84 }
85 
86 
87 /*
88  * Set up for an output pass, and perform any dummy pass(es) needed.
89  * Common subroutine for jpeg_start_decompress and jpeg_start_output.
90  * Entry: global_state = DSTATE_PRESCAN only if previously suspended.
91  * Exit: If done, returns TRUE and sets global_state for proper output mode.
92  * If suspended, returns FALSE and sets global_state = DSTATE_PRESCAN.
93  */
94 
95 LOCAL(boolean)
97 {
98  if (cinfo->global_state != DSTATE_PRESCAN) {
99  /* First call: do pass setup */
100  (*cinfo->master->prepare_for_output_pass) (cinfo);
101  cinfo->output_scanline = 0;
102  cinfo->global_state = DSTATE_PRESCAN;
103  }
104  /* Loop over any required dummy passes */
105  while (cinfo->master->is_dummy_pass) {
106 #ifdef QUANT_2PASS_SUPPORTED
107  /* Crank through the dummy pass */
108  while (cinfo->output_scanline < cinfo->output_height) {
109  JDIMENSION last_scanline;
110  /* Call progress monitor hook if present */
111  if (cinfo->progress != NULL) {
112  cinfo->progress->pass_counter = (long) cinfo->output_scanline;
113  cinfo->progress->pass_limit = (long) cinfo->output_height;
114  (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
115  }
116  /* Process some data */
117  last_scanline = cinfo->output_scanline;
118  (*cinfo->main->process_data) (cinfo, (JSAMPARRAY) NULL,
119  &cinfo->output_scanline, (JDIMENSION) 0);
120  if (cinfo->output_scanline == last_scanline)
121  return FALSE; /* No progress made, must suspend */
122  }
123  /* Finish up dummy pass, and set up for another one */
124  (*cinfo->master->finish_output_pass) (cinfo);
125  (*cinfo->master->prepare_for_output_pass) (cinfo);
126  cinfo->output_scanline = 0;
127 #else
128  ERREXIT(cinfo, JERR_NOT_COMPILED);
129 #endif /* QUANT_2PASS_SUPPORTED */
130  }
131  /* Ready for application to drive output pass through
132  * jpeg_read_scanlines or jpeg_read_raw_data.
133  */
134  cinfo->global_state = cinfo->raw_data_out ? DSTATE_RAW_OK : DSTATE_SCANNING;
135  return TRUE;
136 }
137 
138 
139 /*
140  * Read some scanlines of data from the JPEG decompressor.
141  *
142  * The return value will be the number of lines actually read.
143  * This may be less than the number requested in several cases,
144  * including bottom of image, data source suspension, and operating
145  * modes that emit multiple scanlines at a time.
146  *
147  * Note: we warn about excess calls to jpeg_read_scanlines() since
148  * this likely signals an application programmer error. However,
149  * an oversize buffer (max_lines > scanlines remaining) is not an error.
150  */
151 
155 {
156  JDIMENSION row_ctr;
157 
158  if (cinfo->global_state != DSTATE_SCANNING)
159  ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
160  if (cinfo->output_scanline >= cinfo->output_height) {
161  WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
162  return 0;
163  }
164 
165  /* Call progress monitor hook if present */
166  if (cinfo->progress != NULL) {
167  cinfo->progress->pass_counter = (long) cinfo->output_scanline;
168  cinfo->progress->pass_limit = (long) cinfo->output_height;
169  (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
170  }
171 
172  /* Process some data */
173  row_ctr = 0;
174  (*cinfo->main->process_data) (cinfo, scanlines, &row_ctr, max_lines);
175  cinfo->output_scanline += row_ctr;
176  return row_ctr;
177 }
178 
179 
180 /*
181  * Alternate entry point to read raw data.
182  * Processes exactly one iMCU row per call, unless suspended.
183  */
184 
188 {
189  JDIMENSION lines_per_iMCU_row;
190 
191  if (cinfo->global_state != DSTATE_RAW_OK)
192  ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
193  if (cinfo->output_scanline >= cinfo->output_height) {
194  WARNMS(cinfo, JWRN_TOO_MUCH_DATA);
195  return 0;
196  }
197 
198  /* Call progress monitor hook if present */
199  if (cinfo->progress != NULL) {
200  cinfo->progress->pass_counter = (long) cinfo->output_scanline;
201  cinfo->progress->pass_limit = (long) cinfo->output_height;
202  (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);
203  }
204 
205  /* Verify that at least one iMCU row can be returned. */
206  lines_per_iMCU_row = cinfo->max_v_samp_factor * cinfo->min_DCT_v_scaled_size;
207  if (max_lines < lines_per_iMCU_row)
208  ERREXIT(cinfo, JERR_BUFFER_SIZE);
209 
210  /* Decompress directly into user's buffer. */
211  if (! (*cinfo->coef->decompress_data) (cinfo, data))
212  return 0; /* suspension forced, can do nothing more */
213 
214  /* OK, we processed one iMCU row. */
215  cinfo->output_scanline += lines_per_iMCU_row;
216  return lines_per_iMCU_row;
217 }
218 
219 
220 /* Additional entry points for buffered-image mode. */
221 
222 #ifdef D_MULTISCAN_FILES_SUPPORTED
223 
224 /*
225  * Initialize for an output pass in buffered-image mode.
226  */
227 
228 GLOBAL(boolean)
229 jpeg_start_output (j_decompress_ptr cinfo, int scan_number)
230 {
231  if (cinfo->global_state != DSTATE_BUFIMAGE &&
232  cinfo->global_state != DSTATE_PRESCAN)
233  ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
234  /* Limit scan number to valid range */
235  if (scan_number <= 0)
236  scan_number = 1;
237  if (cinfo->inputctl->eoi_reached &&
241  /* Perform any dummy output passes, and set up for the real pass */
242  return output_pass_setup(cinfo);
243 }
244 
245 
246 /*
247  * Finish up after an output pass in buffered-image mode.
248  *
249  * Returns FALSE if suspended. The return value need be inspected only if
250  * a suspending data source is used.
251  */
252 
253 GLOBAL(boolean)
254 jpeg_finish_output (j_decompress_ptr cinfo)
255 {
256  if ((cinfo->global_state == DSTATE_SCANNING ||
257  cinfo->global_state == DSTATE_RAW_OK) && cinfo->buffered_image) {
258  /* Terminate this pass. */
259  /* We do not require the whole pass to have been completed. */
260  (*cinfo->master->finish_output_pass) (cinfo);
261  cinfo->global_state = DSTATE_BUFPOST;
262  } else if (cinfo->global_state != DSTATE_BUFPOST) {
263  /* BUFPOST = repeat call after a suspension, anything else is error */
264  ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
265  }
266  /* Read markers looking for SOS or EOI */
267  while (cinfo->input_scan_number <= cinfo->output_scan_number &&
268  ! cinfo->inputctl->eoi_reached) {
269  if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)
270  return FALSE; /* Suspend, come back later */
271  }
272  cinfo->global_state = DSTATE_BUFIMAGE;
273  return TRUE;
274 }
275 
276 #endif /* D_MULTISCAN_FILES_SUPPORTED */
#define DSTATE_RAW_OK
Definition: jpegint.h:36
#define TRUE
Definition: types.h:120
int scan_number
Definition: jpeglib.h:1069
#define ERREXIT(msg)
Definition: rdjpgcom.c:72
struct jpeg_input_controller * inputctl
Definition: jpeglib.h:682
#define JPEG_REACHED_SOS
Definition: jpeglib.h:1076
#define JPEG_REACHED_EOI
Definition: jpeglib.h:1077
JSAMPARRAY JDIMENSION max_lines
Definition: jpeglib.h:1057
#define DSTATE_BUFIMAGE
Definition: jpegint.h:37
#define JPEG_ROW_COMPLETED
Definition: jpeglib.h:1078
#define DSTATE_PRELOAD
Definition: jpegint.h:33
LOCAL(boolean)
Definition: jdapistd.c:24
jpeg_read_raw_data(j_decompress_ptr cinfo, JSAMPIMAGE data, JDIMENSION max_lines)
Definition: jdapistd.c:186
smooth NULL
Definition: ftsmooth.c:416
#define DSTATE_READY
Definition: jpegint.h:32
struct jpeg_decomp_master * master
Definition: jpeglib.h:678
#define WARNMS(cinfo, code)
Definition: jerror.h:251
#define DSTATE_SCANNING
Definition: jpegint.h:35
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: gl.h:1950
jinit_master_decompress(j_decompress_ptr cinfo)
Definition: jdmaster.c:526
#define JPP(arglist)
Definition: jpeglib.h:877
JSAMPARRAY * JSAMPIMAGE
Definition: jpeglib.h:77
#define ERREXIT1(cinfo, code, p1)
Definition: jerror.h:212
#define DSTATE_BUFPOST
Definition: jpegint.h:38
JSAMPROW * JSAMPARRAY
Definition: jpeglib.h:76
JSAMPARRAY scanlines
Definition: jpeglib.h:1016
jpeg_read_scanlines(j_decompress_ptr cinfo, JSAMPARRAY scanlines, JDIMENSION max_lines)
Definition: jdapistd.c:153
#define GLOBAL(type)
Definition: jmorecfg.h:291
#define DSTATE_PRESCAN
Definition: jpegint.h:34
output_pass_setup(j_decompress_ptr cinfo)
Definition: jdapistd.c:96
#define long
Definition: qsort.c:33
#define JPEG_SUSPENDED
Definition: jpeglib.h:1045
unsigned int JDIMENSION
Definition: jmorecfg.h:229
boolean buffered_image
Definition: jpeglib.h:484
JDIMENSION total_iMCU_rows
Definition: jpeglib.h:633