source: rtems-graphics-toolkit/jpeg-8d/jcmaster.c @ 8d99938

Last change on this file since 8d99938 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: 30.6 KB
Line 
1/*
2 * jcmaster.c
3 *
4 * Copyright (C) 1991-1997, Thomas G. Lane.
5 * Modified 2003-2011 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 master control logic for the JPEG compressor.
10 * These routines are concerned with parameter validation, initial setup,
11 * and inter-pass control (determining the number of passes and the work
12 * to be done in each pass).
13 */
14
15#define JPEG_INTERNALS
16#include "jinclude.h"
17#include "jpeglib.h"
18
19
20/* Private state */
21
22typedef enum {
23        main_pass,              /* input data, also do first output step */
24        huff_opt_pass,          /* Huffman code optimization pass */
25        output_pass             /* data output pass */
26} c_pass_type;
27
28typedef struct {
29  struct jpeg_comp_master pub;  /* public fields */
30
31  c_pass_type pass_type;        /* the type of the current pass */
32
33  int pass_number;              /* # of passes completed */
34  int total_passes;             /* total # of passes needed */
35
36  int scan_number;              /* current index in scan_info[] */
37} my_comp_master;
38
39typedef my_comp_master * my_master_ptr;
40
41
42/*
43 * Support routines that do various essential calculations.
44 */
45
46/*
47 * Compute JPEG image dimensions and related values.
48 * NOTE: this is exported for possible use by application.
49 * Hence it mustn't do anything that can't be done twice.
50 */
51
52GLOBAL(void)
53jpeg_calc_jpeg_dimensions (j_compress_ptr cinfo)
54/* Do computations that are needed before master selection phase */
55{
56#ifdef DCT_SCALING_SUPPORTED
57
58  /* Sanity check on input image dimensions to prevent overflow in
59   * following calculation.
60   * We do check jpeg_width and jpeg_height in initial_setup below,
61   * but image_width and image_height can come from arbitrary data,
62   * and we need some space for multiplication by block_size.
63   */
64  if (((long) cinfo->image_width >> 24) || ((long) cinfo->image_height >> 24))
65    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
66
67  /* Compute actual JPEG image dimensions and DCT scaling choices. */
68  if (cinfo->scale_num >= cinfo->scale_denom * cinfo->block_size) {
69    /* Provide block_size/1 scaling */
70    cinfo->jpeg_width = cinfo->image_width * cinfo->block_size;
71    cinfo->jpeg_height = cinfo->image_height * cinfo->block_size;
72    cinfo->min_DCT_h_scaled_size = 1;
73    cinfo->min_DCT_v_scaled_size = 1;
74  } else if (cinfo->scale_num * 2 >= cinfo->scale_denom * cinfo->block_size) {
75    /* Provide block_size/2 scaling */
76    cinfo->jpeg_width = (JDIMENSION)
77      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 2L);
78    cinfo->jpeg_height = (JDIMENSION)
79      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 2L);
80    cinfo->min_DCT_h_scaled_size = 2;
81    cinfo->min_DCT_v_scaled_size = 2;
82  } else if (cinfo->scale_num * 3 >= cinfo->scale_denom * cinfo->block_size) {
83    /* Provide block_size/3 scaling */
84    cinfo->jpeg_width = (JDIMENSION)
85      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 3L);
86    cinfo->jpeg_height = (JDIMENSION)
87      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 3L);
88    cinfo->min_DCT_h_scaled_size = 3;
89    cinfo->min_DCT_v_scaled_size = 3;
90  } else if (cinfo->scale_num * 4 >= cinfo->scale_denom * cinfo->block_size) {
91    /* Provide block_size/4 scaling */
92    cinfo->jpeg_width = (JDIMENSION)
93      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 4L);
94    cinfo->jpeg_height = (JDIMENSION)
95      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 4L);
96    cinfo->min_DCT_h_scaled_size = 4;
97    cinfo->min_DCT_v_scaled_size = 4;
98  } else if (cinfo->scale_num * 5 >= cinfo->scale_denom * cinfo->block_size) {
99    /* Provide block_size/5 scaling */
100    cinfo->jpeg_width = (JDIMENSION)
101      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 5L);
102    cinfo->jpeg_height = (JDIMENSION)
103      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 5L);
104    cinfo->min_DCT_h_scaled_size = 5;
105    cinfo->min_DCT_v_scaled_size = 5;
106  } else if (cinfo->scale_num * 6 >= cinfo->scale_denom * cinfo->block_size) {
107    /* Provide block_size/6 scaling */
108    cinfo->jpeg_width = (JDIMENSION)
109      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 6L);
110    cinfo->jpeg_height = (JDIMENSION)
111      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 6L);
112    cinfo->min_DCT_h_scaled_size = 6;
113    cinfo->min_DCT_v_scaled_size = 6;
114  } else if (cinfo->scale_num * 7 >= cinfo->scale_denom * cinfo->block_size) {
115    /* Provide block_size/7 scaling */
116    cinfo->jpeg_width = (JDIMENSION)
117      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 7L);
118    cinfo->jpeg_height = (JDIMENSION)
119      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 7L);
120    cinfo->min_DCT_h_scaled_size = 7;
121    cinfo->min_DCT_v_scaled_size = 7;
122  } else if (cinfo->scale_num * 8 >= cinfo->scale_denom * cinfo->block_size) {
123    /* Provide block_size/8 scaling */
124    cinfo->jpeg_width = (JDIMENSION)
125      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 8L);
126    cinfo->jpeg_height = (JDIMENSION)
127      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 8L);
128    cinfo->min_DCT_h_scaled_size = 8;
129    cinfo->min_DCT_v_scaled_size = 8;
130  } else if (cinfo->scale_num * 9 >= cinfo->scale_denom * cinfo->block_size) {
131    /* Provide block_size/9 scaling */
132    cinfo->jpeg_width = (JDIMENSION)
133      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 9L);
134    cinfo->jpeg_height = (JDIMENSION)
135      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 9L);
136    cinfo->min_DCT_h_scaled_size = 9;
137    cinfo->min_DCT_v_scaled_size = 9;
138  } else if (cinfo->scale_num * 10 >= cinfo->scale_denom * cinfo->block_size) {
139    /* Provide block_size/10 scaling */
140    cinfo->jpeg_width = (JDIMENSION)
141      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 10L);
142    cinfo->jpeg_height = (JDIMENSION)
143      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 10L);
144    cinfo->min_DCT_h_scaled_size = 10;
145    cinfo->min_DCT_v_scaled_size = 10;
146  } else if (cinfo->scale_num * 11 >= cinfo->scale_denom * cinfo->block_size) {
147    /* Provide block_size/11 scaling */
148    cinfo->jpeg_width = (JDIMENSION)
149      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 11L);
150    cinfo->jpeg_height = (JDIMENSION)
151      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 11L);
152    cinfo->min_DCT_h_scaled_size = 11;
153    cinfo->min_DCT_v_scaled_size = 11;
154  } else if (cinfo->scale_num * 12 >= cinfo->scale_denom * cinfo->block_size) {
155    /* Provide block_size/12 scaling */
156    cinfo->jpeg_width = (JDIMENSION)
157      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 12L);
158    cinfo->jpeg_height = (JDIMENSION)
159      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 12L);
160    cinfo->min_DCT_h_scaled_size = 12;
161    cinfo->min_DCT_v_scaled_size = 12;
162  } else if (cinfo->scale_num * 13 >= cinfo->scale_denom * cinfo->block_size) {
163    /* Provide block_size/13 scaling */
164    cinfo->jpeg_width = (JDIMENSION)
165      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 13L);
166    cinfo->jpeg_height = (JDIMENSION)
167      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 13L);
168    cinfo->min_DCT_h_scaled_size = 13;
169    cinfo->min_DCT_v_scaled_size = 13;
170  } else if (cinfo->scale_num * 14 >= cinfo->scale_denom * cinfo->block_size) {
171    /* Provide block_size/14 scaling */
172    cinfo->jpeg_width = (JDIMENSION)
173      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 14L);
174    cinfo->jpeg_height = (JDIMENSION)
175      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 14L);
176    cinfo->min_DCT_h_scaled_size = 14;
177    cinfo->min_DCT_v_scaled_size = 14;
178  } else if (cinfo->scale_num * 15 >= cinfo->scale_denom * cinfo->block_size) {
179    /* Provide block_size/15 scaling */
180    cinfo->jpeg_width = (JDIMENSION)
181      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 15L);
182    cinfo->jpeg_height = (JDIMENSION)
183      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 15L);
184    cinfo->min_DCT_h_scaled_size = 15;
185    cinfo->min_DCT_v_scaled_size = 15;
186  } else {
187    /* Provide block_size/16 scaling */
188    cinfo->jpeg_width = (JDIMENSION)
189      jdiv_round_up((long) cinfo->image_width * cinfo->block_size, 16L);
190    cinfo->jpeg_height = (JDIMENSION)
191      jdiv_round_up((long) cinfo->image_height * cinfo->block_size, 16L);
192    cinfo->min_DCT_h_scaled_size = 16;
193    cinfo->min_DCT_v_scaled_size = 16;
194  }
195
196#else /* !DCT_SCALING_SUPPORTED */
197
198  /* Hardwire it to "no scaling" */
199  cinfo->jpeg_width = cinfo->image_width;
200  cinfo->jpeg_height = cinfo->image_height;
201  cinfo->min_DCT_h_scaled_size = DCTSIZE;
202  cinfo->min_DCT_v_scaled_size = DCTSIZE;
203
204#endif /* DCT_SCALING_SUPPORTED */
205}
206
207
208LOCAL(void)
209jpeg_calc_trans_dimensions (j_compress_ptr cinfo)
210{
211  if (cinfo->min_DCT_h_scaled_size != cinfo->min_DCT_v_scaled_size)
212    ERREXIT2(cinfo, JERR_BAD_DCTSIZE,
213             cinfo->min_DCT_h_scaled_size, cinfo->min_DCT_v_scaled_size);
214
215  cinfo->block_size = cinfo->min_DCT_h_scaled_size;
216}
217
218
219LOCAL(void)
220initial_setup (j_compress_ptr cinfo, boolean transcode_only)
221/* Do computations that are needed before master selection phase */
222{
223  int ci, ssize;
224  jpeg_component_info *compptr;
225  long samplesperrow;
226  JDIMENSION jd_samplesperrow;
227
228  if (transcode_only)
229    jpeg_calc_trans_dimensions(cinfo);
230  else
231    jpeg_calc_jpeg_dimensions(cinfo);
232
233  /* Sanity check on block_size */
234  if (cinfo->block_size < 1 || cinfo->block_size > 16)
235    ERREXIT2(cinfo, JERR_BAD_DCTSIZE, cinfo->block_size, cinfo->block_size);
236
237  /* Derive natural_order from block_size */
238  switch (cinfo->block_size) {
239  case 2: cinfo->natural_order = jpeg_natural_order2; break;
240  case 3: cinfo->natural_order = jpeg_natural_order3; break;
241  case 4: cinfo->natural_order = jpeg_natural_order4; break;
242  case 5: cinfo->natural_order = jpeg_natural_order5; break;
243  case 6: cinfo->natural_order = jpeg_natural_order6; break;
244  case 7: cinfo->natural_order = jpeg_natural_order7; break;
245  default: cinfo->natural_order = jpeg_natural_order; break;
246  }
247
248  /* Derive lim_Se from block_size */
249  cinfo->lim_Se = cinfo->block_size < DCTSIZE ?
250    cinfo->block_size * cinfo->block_size - 1 : DCTSIZE2-1;
251
252  /* Sanity check on image dimensions */
253  if (cinfo->jpeg_height <= 0 || cinfo->jpeg_width <= 0 ||
254      cinfo->num_components <= 0 || cinfo->input_components <= 0)
255    ERREXIT(cinfo, JERR_EMPTY_IMAGE);
256
257  /* Make sure image isn't bigger than I can handle */
258  if ((long) cinfo->jpeg_height > (long) JPEG_MAX_DIMENSION ||
259      (long) cinfo->jpeg_width > (long) JPEG_MAX_DIMENSION)
260    ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
261
262  /* Width of an input scanline must be representable as JDIMENSION. */
263  samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
264  jd_samplesperrow = (JDIMENSION) samplesperrow;
265  if ((long) jd_samplesperrow != samplesperrow)
266    ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
267
268  /* For now, precision must match compiled-in value... */
269  if (cinfo->data_precision != BITS_IN_JSAMPLE)
270    ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
271
272  /* Check that number of components won't exceed internal array sizes */
273  if (cinfo->num_components > MAX_COMPONENTS)
274    ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
275             MAX_COMPONENTS);
276
277  /* Compute maximum sampling factors; check factor validity */
278  cinfo->max_h_samp_factor = 1;
279  cinfo->max_v_samp_factor = 1;
280  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
281       ci++, compptr++) {
282    if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
283        compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
284      ERREXIT(cinfo, JERR_BAD_SAMPLING);
285    cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
286                                   compptr->h_samp_factor);
287    cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
288                                   compptr->v_samp_factor);
289  }
290
291  /* Compute dimensions of components */
292  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
293       ci++, compptr++) {
294    /* Fill in the correct component_index value; don't rely on application */
295    compptr->component_index = ci;
296    /* In selecting the actual DCT scaling for each component, we try to
297     * scale down the chroma components via DCT scaling rather than downsampling.
298     * This saves time if the downsampler gets to use 1:1 scaling.
299     * Note this code adapts subsampling ratios which are powers of 2.
300     */
301    ssize = 1;
302#ifdef DCT_SCALING_SUPPORTED
303    while (cinfo->min_DCT_h_scaled_size * ssize <=
304           (cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
305           (cinfo->max_h_samp_factor % (compptr->h_samp_factor * ssize * 2)) == 0) {
306      ssize = ssize * 2;
307    }
308#endif
309    compptr->DCT_h_scaled_size = cinfo->min_DCT_h_scaled_size * ssize;
310    ssize = 1;
311#ifdef DCT_SCALING_SUPPORTED
312    while (cinfo->min_DCT_v_scaled_size * ssize <=
313           (cinfo->do_fancy_downsampling ? DCTSIZE : DCTSIZE / 2) &&
314           (cinfo->max_v_samp_factor % (compptr->v_samp_factor * ssize * 2)) == 0) {
315      ssize = ssize * 2;
316    }
317#endif
318    compptr->DCT_v_scaled_size = cinfo->min_DCT_v_scaled_size * ssize;
319
320    /* We don't support DCT ratios larger than 2. */
321    if (compptr->DCT_h_scaled_size > compptr->DCT_v_scaled_size * 2)
322        compptr->DCT_h_scaled_size = compptr->DCT_v_scaled_size * 2;
323    else if (compptr->DCT_v_scaled_size > compptr->DCT_h_scaled_size * 2)
324        compptr->DCT_v_scaled_size = compptr->DCT_h_scaled_size * 2;
325
326    /* Size in DCT blocks */
327    compptr->width_in_blocks = (JDIMENSION)
328      jdiv_round_up((long) cinfo->jpeg_width * (long) compptr->h_samp_factor,
329                    (long) (cinfo->max_h_samp_factor * cinfo->block_size));
330    compptr->height_in_blocks = (JDIMENSION)
331      jdiv_round_up((long) cinfo->jpeg_height * (long) compptr->v_samp_factor,
332                    (long) (cinfo->max_v_samp_factor * cinfo->block_size));
333    /* Size in samples */
334    compptr->downsampled_width = (JDIMENSION)
335      jdiv_round_up((long) cinfo->jpeg_width *
336                    (long) (compptr->h_samp_factor * compptr->DCT_h_scaled_size),
337                    (long) (cinfo->max_h_samp_factor * cinfo->block_size));
338    compptr->downsampled_height = (JDIMENSION)
339      jdiv_round_up((long) cinfo->jpeg_height *
340                    (long) (compptr->v_samp_factor * compptr->DCT_v_scaled_size),
341                    (long) (cinfo->max_v_samp_factor * cinfo->block_size));
342    /* Mark component needed (this flag isn't actually used for compression) */
343    compptr->component_needed = TRUE;
344  }
345
346  /* Compute number of fully interleaved MCU rows (number of times that
347   * main controller will call coefficient controller).
348   */
349  cinfo->total_iMCU_rows = (JDIMENSION)
350    jdiv_round_up((long) cinfo->jpeg_height,
351                  (long) (cinfo->max_v_samp_factor * cinfo->block_size));
352}
353
354
355#ifdef C_MULTISCAN_FILES_SUPPORTED
356
357LOCAL(void)
358validate_script (j_compress_ptr cinfo)
359/* Verify that the scan script in cinfo->scan_info[] is valid; also
360 * determine whether it uses progressive JPEG, and set cinfo->progressive_mode.
361 */
362{
363  const jpeg_scan_info * scanptr;
364  int scanno, ncomps, ci, coefi, thisi;
365  int Ss, Se, Ah, Al;
366  boolean component_sent[MAX_COMPONENTS];
367#ifdef C_PROGRESSIVE_SUPPORTED
368  int * last_bitpos_ptr;
369  int last_bitpos[MAX_COMPONENTS][DCTSIZE2];
370  /* -1 until that coefficient has been seen; then last Al for it */
371#endif
372
373  if (cinfo->num_scans <= 0)
374    ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, 0);
375
376  /* For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
377   * for progressive JPEG, no scan can have this.
378   */
379  scanptr = cinfo->scan_info;
380  if (scanptr->Ss != 0 || scanptr->Se != DCTSIZE2-1) {
381#ifdef C_PROGRESSIVE_SUPPORTED
382    cinfo->progressive_mode = TRUE;
383    last_bitpos_ptr = & last_bitpos[0][0];
384    for (ci = 0; ci < cinfo->num_components; ci++) 
385      for (coefi = 0; coefi < DCTSIZE2; coefi++)
386        *last_bitpos_ptr++ = -1;
387#else
388    ERREXIT(cinfo, JERR_NOT_COMPILED);
389#endif
390  } else {
391    cinfo->progressive_mode = FALSE;
392    for (ci = 0; ci < cinfo->num_components; ci++) 
393      component_sent[ci] = FALSE;
394  }
395
396  for (scanno = 1; scanno <= cinfo->num_scans; scanptr++, scanno++) {
397    /* Validate component indexes */
398    ncomps = scanptr->comps_in_scan;
399    if (ncomps <= 0 || ncomps > MAX_COMPS_IN_SCAN)
400      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
401    for (ci = 0; ci < ncomps; ci++) {
402      thisi = scanptr->component_index[ci];
403      if (thisi < 0 || thisi >= cinfo->num_components)
404        ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
405      /* Components must appear in SOF order within each scan */
406      if (ci > 0 && thisi <= scanptr->component_index[ci-1])
407        ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
408    }
409    /* Validate progression parameters */
410    Ss = scanptr->Ss;
411    Se = scanptr->Se;
412    Ah = scanptr->Ah;
413    Al = scanptr->Al;
414    if (cinfo->progressive_mode) {
415#ifdef C_PROGRESSIVE_SUPPORTED
416      /* The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
417       * seems wrong: the upper bound ought to depend on data precision.
418       * Perhaps they really meant 0..N+1 for N-bit precision.
419       * Here we allow 0..10 for 8-bit data; Al larger than 10 results in
420       * out-of-range reconstructed DC values during the first DC scan,
421       * which might cause problems for some decoders.
422       */
423#if BITS_IN_JSAMPLE == 8
424#define MAX_AH_AL 10
425#else
426#define MAX_AH_AL 13
427#endif
428      if (Ss < 0 || Ss >= DCTSIZE2 || Se < Ss || Se >= DCTSIZE2 ||
429          Ah < 0 || Ah > MAX_AH_AL || Al < 0 || Al > MAX_AH_AL)
430        ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
431      if (Ss == 0) {
432        if (Se != 0)            /* DC and AC together not OK */
433          ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
434      } else {
435        if (ncomps != 1)        /* AC scans must be for only one component */
436          ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
437      }
438      for (ci = 0; ci < ncomps; ci++) {
439        last_bitpos_ptr = & last_bitpos[scanptr->component_index[ci]][0];
440        if (Ss != 0 && last_bitpos_ptr[0] < 0) /* AC without prior DC scan */
441          ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
442        for (coefi = Ss; coefi <= Se; coefi++) {
443          if (last_bitpos_ptr[coefi] < 0) {
444            /* first scan of this coefficient */
445            if (Ah != 0)
446              ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
447          } else {
448            /* not first scan */
449            if (Ah != last_bitpos_ptr[coefi] || Al != Ah-1)
450              ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
451          }
452          last_bitpos_ptr[coefi] = Al;
453        }
454      }
455#endif
456    } else {
457      /* For sequential JPEG, all progression parameters must be these: */
458      if (Ss != 0 || Se != DCTSIZE2-1 || Ah != 0 || Al != 0)
459        ERREXIT1(cinfo, JERR_BAD_PROG_SCRIPT, scanno);
460      /* Make sure components are not sent twice */
461      for (ci = 0; ci < ncomps; ci++) {
462        thisi = scanptr->component_index[ci];
463        if (component_sent[thisi])
464          ERREXIT1(cinfo, JERR_BAD_SCAN_SCRIPT, scanno);
465        component_sent[thisi] = TRUE;
466      }
467    }
468  }
469
470  /* Now verify that everything got sent. */
471  if (cinfo->progressive_mode) {
472#ifdef C_PROGRESSIVE_SUPPORTED
473    /* For progressive mode, we only check that at least some DC data
474     * got sent for each component; the spec does not require that all bits
475     * of all coefficients be transmitted.  Would it be wiser to enforce
476     * transmission of all coefficient bits??
477     */
478    for (ci = 0; ci < cinfo->num_components; ci++) {
479      if (last_bitpos[ci][0] < 0)
480        ERREXIT(cinfo, JERR_MISSING_DATA);
481    }
482#endif
483  } else {
484    for (ci = 0; ci < cinfo->num_components; ci++) {
485      if (! component_sent[ci])
486        ERREXIT(cinfo, JERR_MISSING_DATA);
487    }
488  }
489}
490
491
492LOCAL(void)
493reduce_script (j_compress_ptr cinfo)
494/* Adapt scan script for use with reduced block size;
495 * assume that script has been validated before.
496 */
497{
498  jpeg_scan_info * scanptr;
499  int idxout, idxin;
500
501  /* Circumvent const declaration for this function */
502  scanptr = (jpeg_scan_info *) cinfo->scan_info;
503  idxout = 0;
504
505  for (idxin = 0; idxin < cinfo->num_scans; idxin++) {
506    /* After skipping, idxout becomes smaller than idxin */
507    if (idxin != idxout)
508      /* Copy rest of data;
509       * note we stay in given chunk of allocated memory.
510       */
511      scanptr[idxout] = scanptr[idxin];
512    if (scanptr[idxout].Ss > cinfo->lim_Se)
513      /* Entire scan out of range - skip this entry */
514      continue;
515    if (scanptr[idxout].Se > cinfo->lim_Se)
516      /* Limit scan to end of block */
517      scanptr[idxout].Se = cinfo->lim_Se;
518    idxout++;
519  }
520
521  cinfo->num_scans = idxout;
522}
523
524#endif /* C_MULTISCAN_FILES_SUPPORTED */
525
526
527LOCAL(void)
528select_scan_parameters (j_compress_ptr cinfo)
529/* Set up the scan parameters for the current scan */
530{
531  int ci;
532
533#ifdef C_MULTISCAN_FILES_SUPPORTED
534  if (cinfo->scan_info != NULL) {
535    /* Prepare for current scan --- the script is already validated */
536    my_master_ptr master = (my_master_ptr) cinfo->master;
537    const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
538
539    cinfo->comps_in_scan = scanptr->comps_in_scan;
540    for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
541      cinfo->cur_comp_info[ci] =
542        &cinfo->comp_info[scanptr->component_index[ci]];
543    }
544    if (cinfo->progressive_mode) {
545      cinfo->Ss = scanptr->Ss;
546      cinfo->Se = scanptr->Se;
547      cinfo->Ah = scanptr->Ah;
548      cinfo->Al = scanptr->Al;
549      return;
550    }
551  }
552  else
553#endif
554  {
555    /* Prepare for single sequential-JPEG scan containing all components */
556    if (cinfo->num_components > MAX_COMPS_IN_SCAN)
557      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
558               MAX_COMPS_IN_SCAN);
559    cinfo->comps_in_scan = cinfo->num_components;
560    for (ci = 0; ci < cinfo->num_components; ci++) {
561      cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
562    }
563  }
564  cinfo->Ss = 0;
565  cinfo->Se = cinfo->block_size * cinfo->block_size - 1;
566  cinfo->Ah = 0;
567  cinfo->Al = 0;
568}
569
570
571LOCAL(void)
572per_scan_setup (j_compress_ptr cinfo)
573/* Do computations that are needed before processing a JPEG scan */
574/* cinfo->comps_in_scan and cinfo->cur_comp_info[] are already set */
575{
576  int ci, mcublks, tmp;
577  jpeg_component_info *compptr;
578 
579  if (cinfo->comps_in_scan == 1) {
580   
581    /* Noninterleaved (single-component) scan */
582    compptr = cinfo->cur_comp_info[0];
583   
584    /* Overall image size in MCUs */
585    cinfo->MCUs_per_row = compptr->width_in_blocks;
586    cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
587   
588    /* For noninterleaved scan, always one block per MCU */
589    compptr->MCU_width = 1;
590    compptr->MCU_height = 1;
591    compptr->MCU_blocks = 1;
592    compptr->MCU_sample_width = compptr->DCT_h_scaled_size;
593    compptr->last_col_width = 1;
594    /* For noninterleaved scans, it is convenient to define last_row_height
595     * as the number of block rows present in the last iMCU row.
596     */
597    tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
598    if (tmp == 0) tmp = compptr->v_samp_factor;
599    compptr->last_row_height = tmp;
600   
601    /* Prepare array describing MCU composition */
602    cinfo->blocks_in_MCU = 1;
603    cinfo->MCU_membership[0] = 0;
604   
605  } else {
606   
607    /* Interleaved (multi-component) scan */
608    if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
609      ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
610               MAX_COMPS_IN_SCAN);
611   
612    /* Overall image size in MCUs */
613    cinfo->MCUs_per_row = (JDIMENSION)
614      jdiv_round_up((long) cinfo->jpeg_width,
615                    (long) (cinfo->max_h_samp_factor * cinfo->block_size));
616    cinfo->MCU_rows_in_scan = (JDIMENSION)
617      jdiv_round_up((long) cinfo->jpeg_height,
618                    (long) (cinfo->max_v_samp_factor * cinfo->block_size));
619   
620    cinfo->blocks_in_MCU = 0;
621   
622    for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
623      compptr = cinfo->cur_comp_info[ci];
624      /* Sampling factors give # of blocks of component in each MCU */
625      compptr->MCU_width = compptr->h_samp_factor;
626      compptr->MCU_height = compptr->v_samp_factor;
627      compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
628      compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_h_scaled_size;
629      /* Figure number of non-dummy blocks in last MCU column & row */
630      tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
631      if (tmp == 0) tmp = compptr->MCU_width;
632      compptr->last_col_width = tmp;
633      tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
634      if (tmp == 0) tmp = compptr->MCU_height;
635      compptr->last_row_height = tmp;
636      /* Prepare array describing MCU composition */
637      mcublks = compptr->MCU_blocks;
638      if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
639        ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
640      while (mcublks-- > 0) {
641        cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
642      }
643    }
644   
645  }
646
647  /* Convert restart specified in rows to actual MCU count. */
648  /* Note that count must fit in 16 bits, so we provide limiting. */
649  if (cinfo->restart_in_rows > 0) {
650    long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
651    cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
652  }
653}
654
655
656/*
657 * Per-pass setup.
658 * This is called at the beginning of each pass.  We determine which modules
659 * will be active during this pass and give them appropriate start_pass calls.
660 * We also set is_last_pass to indicate whether any more passes will be
661 * required.
662 */
663
664METHODDEF(void)
665prepare_for_pass (j_compress_ptr cinfo)
666{
667  my_master_ptr master = (my_master_ptr) cinfo->master;
668
669  switch (master->pass_type) {
670  case main_pass:
671    /* Initial pass: will collect input data, and do either Huffman
672     * optimization or data output for the first scan.
673     */
674    select_scan_parameters(cinfo);
675    per_scan_setup(cinfo);
676    if (! cinfo->raw_data_in) {
677      (*cinfo->cconvert->start_pass) (cinfo);
678      (*cinfo->downsample->start_pass) (cinfo);
679      (*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
680    }
681    (*cinfo->fdct->start_pass) (cinfo);
682    (*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
683    (*cinfo->coef->start_pass) (cinfo,
684                                (master->total_passes > 1 ?
685                                 JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
686    (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
687    if (cinfo->optimize_coding) {
688      /* No immediate data output; postpone writing frame/scan headers */
689      master->pub.call_pass_startup = FALSE;
690    } else {
691      /* Will write frame/scan headers at first jpeg_write_scanlines call */
692      master->pub.call_pass_startup = TRUE;
693    }
694    break;
695#ifdef ENTROPY_OPT_SUPPORTED
696  case huff_opt_pass:
697    /* Do Huffman optimization for a scan after the first one. */
698    select_scan_parameters(cinfo);
699    per_scan_setup(cinfo);
700    if (cinfo->Ss != 0 || cinfo->Ah == 0) {
701      (*cinfo->entropy->start_pass) (cinfo, TRUE);
702      (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
703      master->pub.call_pass_startup = FALSE;
704      break;
705    }
706    /* Special case: Huffman DC refinement scans need no Huffman table
707     * and therefore we can skip the optimization pass for them.
708     */
709    master->pass_type = output_pass;
710    master->pass_number++;
711    /*FALLTHROUGH*/
712#endif
713  case output_pass:
714    /* Do a data-output pass. */
715    /* We need not repeat per-scan setup if prior optimization pass did it. */
716    if (! cinfo->optimize_coding) {
717      select_scan_parameters(cinfo);
718      per_scan_setup(cinfo);
719    }
720    (*cinfo->entropy->start_pass) (cinfo, FALSE);
721    (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
722    /* We emit frame/scan headers now */
723    if (master->scan_number == 0)
724      (*cinfo->marker->write_frame_header) (cinfo);
725    (*cinfo->marker->write_scan_header) (cinfo);
726    master->pub.call_pass_startup = FALSE;
727    break;
728  default:
729    ERREXIT(cinfo, JERR_NOT_COMPILED);
730  }
731
732  master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
733
734  /* Set up progress monitor's pass info if present */
735  if (cinfo->progress != NULL) {
736    cinfo->progress->completed_passes = master->pass_number;
737    cinfo->progress->total_passes = master->total_passes;
738  }
739}
740
741
742/*
743 * Special start-of-pass hook.
744 * This is called by jpeg_write_scanlines if call_pass_startup is TRUE.
745 * In single-pass processing, we need this hook because we don't want to
746 * write frame/scan headers during jpeg_start_compress; we want to let the
747 * application write COM markers etc. between jpeg_start_compress and the
748 * jpeg_write_scanlines loop.
749 * In multi-pass processing, this routine is not used.
750 */
751
752METHODDEF(void)
753pass_startup (j_compress_ptr cinfo)
754{
755  cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
756
757  (*cinfo->marker->write_frame_header) (cinfo);
758  (*cinfo->marker->write_scan_header) (cinfo);
759}
760
761
762/*
763 * Finish up at end of pass.
764 */
765
766METHODDEF(void)
767finish_pass_master (j_compress_ptr cinfo)
768{
769  my_master_ptr master = (my_master_ptr) cinfo->master;
770
771  /* The entropy coder always needs an end-of-pass call,
772   * either to analyze statistics or to flush its output buffer.
773   */
774  (*cinfo->entropy->finish_pass) (cinfo);
775
776  /* Update state for next pass */
777  switch (master->pass_type) {
778  case main_pass:
779    /* next pass is either output of scan 0 (after optimization)
780     * or output of scan 1 (if no optimization).
781     */
782    master->pass_type = output_pass;
783    if (! cinfo->optimize_coding)
784      master->scan_number++;
785    break;
786  case huff_opt_pass:
787    /* next pass is always output of current scan */
788    master->pass_type = output_pass;
789    break;
790  case output_pass:
791    /* next pass is either optimization or output of next scan */
792    if (cinfo->optimize_coding)
793      master->pass_type = huff_opt_pass;
794    master->scan_number++;
795    break;
796  }
797
798  master->pass_number++;
799}
800
801
802/*
803 * Initialize master compression control.
804 */
805
806GLOBAL(void)
807jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)
808{
809  my_master_ptr master;
810
811  master = (my_master_ptr)
812      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
813                                  SIZEOF(my_comp_master));
814  cinfo->master = (struct jpeg_comp_master *) master;
815  master->pub.prepare_for_pass = prepare_for_pass;
816  master->pub.pass_startup = pass_startup;
817  master->pub.finish_pass = finish_pass_master;
818  master->pub.is_last_pass = FALSE;
819
820  /* Validate parameters, determine derived values */
821  initial_setup(cinfo, transcode_only);
822
823  if (cinfo->scan_info != NULL) {
824#ifdef C_MULTISCAN_FILES_SUPPORTED
825    validate_script(cinfo);
826    if (cinfo->block_size < DCTSIZE)
827      reduce_script(cinfo);
828#else
829    ERREXIT(cinfo, JERR_NOT_COMPILED);
830#endif
831  } else {
832    cinfo->progressive_mode = FALSE;
833    cinfo->num_scans = 1;
834  }
835
836  if ((cinfo->progressive_mode || cinfo->block_size < DCTSIZE) &&
837      !cinfo->arith_code)                       /*  TEMPORARY HACK ??? */
838    /* assume default tables no good for progressive or downscale mode */
839    cinfo->optimize_coding = TRUE;
840
841  /* Initialize my private state */
842  if (transcode_only) {
843    /* no main pass in transcoding */
844    if (cinfo->optimize_coding)
845      master->pass_type = huff_opt_pass;
846    else
847      master->pass_type = output_pass;
848  } else {
849    /* for normal compression, first pass is always this type: */
850    master->pass_type = main_pass;
851  }
852  master->scan_number = 0;
853  master->pass_number = 0;
854  if (cinfo->optimize_coding)
855    master->total_passes = cinfo->num_scans * 2;
856  else
857    master->total_passes = cinfo->num_scans;
858}
Note: See TracBrowser for help on using the repository browser.