Visualization Library 2.0.0-b5

A lightweight C++ OpenGL middleware for 2D/3D graphics

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jctrans.c
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1 /*
2  * jctrans.c
3  *
4  * Copyright (C) 1995-1998, Thomas G. Lane.
5  * This file is part of the Independent JPEG Group's software.
6  * For conditions of distribution and use, see the accompanying README file.
7  *
8  * This file contains library routines for transcoding compression,
9  * that is, writing raw DCT coefficient arrays to an output JPEG file.
10  * The routines in jcapimin.c will also be needed by a transcoder.
11  */
12 
13 #define JPEG_INTERNALS
14 #include "jinclude.h"
15 #include "jpeglib.h"
16 
17 
18 /* Forward declarations */
23 
24 
25 /*
26  * Compression initialization for writing raw-coefficient data.
27  * Before calling this, all parameters and a data destination must be set up.
28  * Call jpeg_finish_compress() to actually write the data.
29  *
30  * The number of passed virtual arrays must match cinfo->num_components.
31  * Note that the virtual arrays need not be filled or even realized at
32  * the time write_coefficients is called; indeed, if the virtual arrays
33  * were requested from this compression object's memory manager, they
34  * typically will be realized during this routine and filled afterwards.
35  */
36 
37 GLOBAL(void)
38 jpeg_write_coefficients (j_compress_ptr cinfo, jvirt_barray_ptr * coef_arrays)
39 {
40  if (cinfo->global_state != CSTATE_START)
41  ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
42  /* Mark all tables to be written */
44  /* (Re)initialize error mgr and destination modules */
45  (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);
46  (*cinfo->dest->init_destination) (cinfo);
47  /* Perform master selection of active modules */
48  transencode_master_selection(cinfo, coef_arrays);
49  /* Wait for jpeg_finish_compress() call */
50  cinfo->next_scanline = 0; /* so jpeg_write_marker works */
51  cinfo->global_state = CSTATE_WRCOEFS;
52 }
53 
54 
55 /*
56  * Initialize the compression object with default parameters,
57  * then copy from the source object all parameters needed for lossless
58  * transcoding. Parameters that can be varied without loss (such as
59  * scan script and Huffman optimization) are left in their default states.
60  */
61 
62 GLOBAL(void)
65 {
66  JQUANT_TBL ** qtblptr;
67  jpeg_component_info *incomp, *outcomp;
68  JQUANT_TBL *c_quant, *slot_quant;
69  int tblno, ci, coefi;
70 
71  /* Safety check to ensure start_compress not called yet. */
72  if (dstinfo->global_state != CSTATE_START)
73  ERREXIT1(dstinfo, JERR_BAD_STATE, dstinfo->global_state);
74  /* Copy fundamental image dimensions */
75  dstinfo->image_width = srcinfo->image_width;
76  dstinfo->image_height = srcinfo->image_height;
77  dstinfo->input_components = srcinfo->num_components;
78  dstinfo->in_color_space = srcinfo->jpeg_color_space;
79  /* Initialize all parameters to default values */
80  jpeg_set_defaults(dstinfo);
81  /* jpeg_set_defaults may choose wrong colorspace, eg YCbCr if input is RGB.
82  * Fix it to get the right header markers for the image colorspace.
83  */
84  jpeg_set_colorspace(dstinfo, srcinfo->jpeg_color_space);
85  dstinfo->data_precision = srcinfo->data_precision;
86  dstinfo->CCIR601_sampling = srcinfo->CCIR601_sampling;
87  /* Copy the source's quantization tables. */
88  for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
89  if (srcinfo->quant_tbl_ptrs[tblno] != NULL) {
90  qtblptr = & dstinfo->quant_tbl_ptrs[tblno];
91  if (*qtblptr == NULL)
92  *qtblptr = jpeg_alloc_quant_table((j_common_ptr) dstinfo);
93  MEMCOPY((*qtblptr)->quantval,
94  srcinfo->quant_tbl_ptrs[tblno]->quantval,
95  SIZEOF((*qtblptr)->quantval));
96  (*qtblptr)->sent_table = FALSE;
97  }
98  }
99  /* Copy the source's per-component info.
100  * Note we assume jpeg_set_defaults has allocated the dest comp_info array.
101  */
102  dstinfo->num_components = srcinfo->num_components;
103  if (dstinfo->num_components < 1 || dstinfo->num_components > MAX_COMPONENTS)
104  ERREXIT2(dstinfo, JERR_COMPONENT_COUNT, dstinfo->num_components,
106  for (ci = 0, incomp = srcinfo->comp_info, outcomp = dstinfo->comp_info;
107  ci < dstinfo->num_components; ci++, incomp++, outcomp++) {
108  outcomp->component_id = incomp->component_id;
109  outcomp->h_samp_factor = incomp->h_samp_factor;
110  outcomp->v_samp_factor = incomp->v_samp_factor;
111  outcomp->quant_tbl_no = incomp->quant_tbl_no;
112  /* Make sure saved quantization table for component matches the qtable
113  * slot. If not, the input file re-used this qtable slot.
114  * IJG encoder currently cannot duplicate this.
115  */
116  tblno = outcomp->quant_tbl_no;
117  if (tblno < 0 || tblno >= NUM_QUANT_TBLS ||
118  srcinfo->quant_tbl_ptrs[tblno] == NULL)
119  ERREXIT1(dstinfo, JERR_NO_QUANT_TABLE, tblno);
120  slot_quant = srcinfo->quant_tbl_ptrs[tblno];
121  c_quant = incomp->quant_table;
122  if (c_quant != NULL) {
123  for (coefi = 0; coefi < DCTSIZE2; coefi++) {
124  if (c_quant->quantval[coefi] != slot_quant->quantval[coefi])
125  ERREXIT1(dstinfo, JERR_MISMATCHED_QUANT_TABLE, tblno);
126  }
127  }
128  /* Note: we do not copy the source's Huffman table assignments;
129  * instead we rely on jpeg_set_colorspace to have made a suitable choice.
130  */
131  }
132  /* Also copy JFIF version and resolution information, if available.
133  * Strictly speaking this isn't "critical" info, but it's nearly
134  * always appropriate to copy it if available. In particular,
135  * if the application chooses to copy JFIF 1.02 extension markers from
136  * the source file, we need to copy the version to make sure we don't
137  * emit a file that has 1.02 extensions but a claimed version of 1.01.
138  * We will *not*, however, copy version info from mislabeled "2.01" files.
139  */
140  if (srcinfo->saw_JFIF_marker) {
141  if (srcinfo->JFIF_major_version == 1) {
142  dstinfo->JFIF_major_version = srcinfo->JFIF_major_version;
143  dstinfo->JFIF_minor_version = srcinfo->JFIF_minor_version;
144  }
145  dstinfo->density_unit = srcinfo->density_unit;
146  dstinfo->X_density = srcinfo->X_density;
147  dstinfo->Y_density = srcinfo->Y_density;
148  }
149 }
150 
151 
152 /*
153  * Master selection of compression modules for transcoding.
154  * This substitutes for jcinit.c's initialization of the full compressor.
155  */
156 
157 LOCAL(void)
159  jvirt_barray_ptr * coef_arrays)
160 {
161  /* Although we don't actually use input_components for transcoding,
162  * jcmaster.c's initial_setup will complain if input_components is 0.
163  */
164  cinfo->input_components = 1;
165  /* Initialize master control (includes parameter checking/processing) */
166  jinit_c_master_control(cinfo, TRUE /* transcode only */);
167 
168  /* Entropy encoding: either Huffman or arithmetic coding. */
169  if (cinfo->arith_code) {
170  ERREXIT(cinfo, JERR_ARITH_NOTIMPL);
171  } else {
172  if (cinfo->progressive_mode) {
173 #ifdef C_PROGRESSIVE_SUPPORTED
174  jinit_phuff_encoder(cinfo);
175 #else
176  ERREXIT(cinfo, JERR_NOT_COMPILED);
177 #endif
178  } else
179  jinit_huff_encoder(cinfo);
180  }
181 
182  /* We need a special coefficient buffer controller. */
183  transencode_coef_controller(cinfo, coef_arrays);
184 
185  jinit_marker_writer(cinfo);
186 
187  /* We can now tell the memory manager to allocate virtual arrays. */
188  (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo);
189 
190  /* Write the datastream header (SOI, JFIF) immediately.
191  * Frame and scan headers are postponed till later.
192  * This lets application insert special markers after the SOI.
193  */
194  (*cinfo->marker->write_file_header) (cinfo);
195 }
196 
197 
198 /*
199  * The rest of this file is a special implementation of the coefficient
200  * buffer controller. This is similar to jccoefct.c, but it handles only
201  * output from presupplied virtual arrays. Furthermore, we generate any
202  * dummy padding blocks on-the-fly rather than expecting them to be present
203  * in the arrays.
204  */
205 
206 /* Private buffer controller object */
207 
208 typedef struct {
209  struct jpeg_c_coef_controller pub; /* public fields */
210 
211  JDIMENSION iMCU_row_num; /* iMCU row # within image */
212  JDIMENSION mcu_ctr; /* counts MCUs processed in current row */
213  int MCU_vert_offset; /* counts MCU rows within iMCU row */
214  int MCU_rows_per_iMCU_row; /* number of such rows needed */
215 
216  /* Virtual block array for each component. */
217  jvirt_barray_ptr * whole_image;
218 
219  /* Workspace for constructing dummy blocks at right/bottom edges. */
220  JBLOCKROW dummy_buffer[C_MAX_BLOCKS_IN_MCU];
221 } my_coef_controller;
222 
223 typedef my_coef_controller * my_coef_ptr;
224 
225 
226 LOCAL(void)
228 /* Reset within-iMCU-row counters for a new row */
229 {
230  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
231 
232  /* In an interleaved scan, an MCU row is the same as an iMCU row.
233  * In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.
234  * But at the bottom of the image, process only what's left.
235  */
236  if (cinfo->comps_in_scan > 1) {
237  coef->MCU_rows_per_iMCU_row = 1;
238  } else {
239  if (coef->iMCU_row_num < (cinfo->total_iMCU_rows-1))
240  coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->v_samp_factor;
241  else
242  coef->MCU_rows_per_iMCU_row = cinfo->cur_comp_info[0]->last_row_height;
243  }
244 
245  coef->mcu_ctr = 0;
246  coef->MCU_vert_offset = 0;
247 }
248 
249 
250 /*
251  * Initialize for a processing pass.
252  */
253 
254 METHODDEF(void)
256 {
257  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
258 
259  if (pass_mode != JBUF_CRANK_DEST)
260  ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
261 
262  coef->iMCU_row_num = 0;
263  start_iMCU_row(cinfo);
264 }
265 
266 
267 /*
268  * Process some data.
269  * We process the equivalent of one fully interleaved MCU row ("iMCU" row)
270  * per call, ie, v_samp_factor block rows for each component in the scan.
271  * The data is obtained from the virtual arrays and fed to the entropy coder.
272  * Returns TRUE if the iMCU row is completed, FALSE if suspended.
273  *
274  * NB: input_buf is ignored; it is likely to be a NULL pointer.
275  */
276 
277 METHODDEF(boolean)
279 {
280  my_coef_ptr coef = (my_coef_ptr) cinfo->coef;
281  JDIMENSION MCU_col_num; /* index of current MCU within row */
282  JDIMENSION last_MCU_col = cinfo->MCUs_per_row - 1;
283  JDIMENSION last_iMCU_row = cinfo->total_iMCU_rows - 1;
284  int blkn, ci, xindex, yindex, yoffset, blockcnt;
285  JDIMENSION start_col;
287  JBLOCKROW MCU_buffer[C_MAX_BLOCKS_IN_MCU];
288  JBLOCKROW buffer_ptr;
290 
291  /* Align the virtual buffers for the components used in this scan. */
292  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
293  compptr = cinfo->cur_comp_info[ci];
294  buffer[ci] = (*cinfo->mem->access_virt_barray)
295  ((j_common_ptr) cinfo, coef->whole_image[compptr->component_index],
296  coef->iMCU_row_num * compptr->v_samp_factor,
298  }
299 
300  /* Loop to process one whole iMCU row */
301  for (yoffset = coef->MCU_vert_offset; yoffset < coef->MCU_rows_per_iMCU_row;
302  yoffset++) {
303  for (MCU_col_num = coef->mcu_ctr; MCU_col_num < cinfo->MCUs_per_row;
304  MCU_col_num++) {
305  /* Construct list of pointers to DCT blocks belonging to this MCU */
306  blkn = 0; /* index of current DCT block within MCU */
307  for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
308  compptr = cinfo->cur_comp_info[ci];
309  start_col = MCU_col_num * compptr->MCU_width;
310  blockcnt = (MCU_col_num < last_MCU_col) ? compptr->MCU_width
312  for (yindex = 0; yindex < compptr->MCU_height; yindex++) {
313  if (coef->iMCU_row_num < last_iMCU_row ||
314  yindex+yoffset < compptr->last_row_height) {
315  /* Fill in pointers to real blocks in this row */
316  buffer_ptr = buffer[ci][yindex+yoffset] + start_col;
317  for (xindex = 0; xindex < blockcnt; xindex++)
318  MCU_buffer[blkn++] = buffer_ptr++;
319  } else {
320  /* At bottom of image, need a whole row of dummy blocks */
321  xindex = 0;
322  }
323  /* Fill in any dummy blocks needed in this row.
324  * Dummy blocks are filled in the same way as in jccoefct.c:
325  * all zeroes in the AC entries, DC entries equal to previous
326  * block's DC value. The init routine has already zeroed the
327  * AC entries, so we need only set the DC entries correctly.
328  */
329  for (; xindex < compptr->MCU_width; xindex++) {
330  MCU_buffer[blkn] = coef->dummy_buffer[blkn];
331  MCU_buffer[blkn][0][0] = MCU_buffer[blkn-1][0][0];
332  blkn++;
333  }
334  }
335  }
336  /* Try to write the MCU. */
337  if (! (*cinfo->entropy->encode_mcu) (cinfo, MCU_buffer)) {
338  /* Suspension forced; update state counters and exit */
339  coef->MCU_vert_offset = yoffset;
340  coef->mcu_ctr = MCU_col_num;
341  return FALSE;
342  }
343  }
344  /* Completed an MCU row, but perhaps not an iMCU row */
345  coef->mcu_ctr = 0;
346  }
347  /* Completed the iMCU row, advance counters for next one */
348  coef->iMCU_row_num++;
349  start_iMCU_row(cinfo);
350  return TRUE;
351 }
352 
353 
354 /*
355  * Initialize coefficient buffer controller.
356  *
357  * Each passed coefficient array must be the right size for that
358  * coefficient: width_in_blocks wide and height_in_blocks high,
359  * with unitheight at least v_samp_factor.
360  */
361 
362 LOCAL(void)
364  jvirt_barray_ptr * coef_arrays)
365 {
366  my_coef_ptr coef;
368  int i;
369 
370  coef = (my_coef_ptr)
371  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
372  SIZEOF(my_coef_controller));
373  cinfo->coef = (struct jpeg_c_coef_controller *) coef;
374  coef->pub.start_pass = start_pass_coef;
375  coef->pub.compress_data = compress_output;
376 
377  /* Save pointer to virtual arrays */
378  coef->whole_image = coef_arrays;
379 
380  /* Allocate and pre-zero space for dummy DCT blocks. */
381  buffer = (JBLOCKROW)
382  (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
384  jzero_far((void FAR *) buffer, C_MAX_BLOCKS_IN_MCU * SIZEOF(JBLOCK));
385  for (i = 0; i < C_MAX_BLOCKS_IN_MCU; i++) {
386  coef->dummy_buffer[i] = buffer + i;
387  }
388 }
for(n=1;n< outline->n_points;n++)
Definition: ftbbox.c:593
UINT16 quantval[DCTSIZE2]
Definition: jpeglib.h:88
#define CSTATE_START
Definition: jpegint.h:25
my_coef_controller * my_coef_ptr
Definition: jctrans.c:223
#define NUM_QUANT_TBLS
Definition: jpeglib.h:43
transencode_coef_controller(j_compress_ptr cinfo, jvirt_barray_ptr *coef_arrays)
Definition: jctrans.c:363
#define NULL
Definition: ftobjs.h:61
start_pass_coef(j_compress_ptr cinfo, J_BUF_MODE pass_mode)
Definition: jctrans.c:255
transencode_master_selection(j_compress_ptr cinfo, jvirt_barray_ptr *coef_arrays)
Definition: jctrans.c:158
struct jpeg_common_struct * j_common_ptr
Definition: jpeglib.h:261
JCOEF JBLOCK[DCTSIZE2]
Definition: jpeglib.h:70
JBLOCKROW * JBLOCKARRAY
Definition: jpeglib.h:72
#define MAX_COMPONENTS
Definition: jmorecfg.h:35
#define ERREXIT(cinfo, code)
Definition: jerror.h:205
#define SIZEOF(object)
Definition: jinclude.h:80
jvirt_barray_ptr * coef_arrays
Definition: jpeglib.h:1017
png_uint_32 i
Definition: png.h:2640
jpeg_component_info * compptr
Definition: jdct.h:102
jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress)
Definition: jcapimin.c:119
JDIMENSION next_scanline
Definition: jpeglib.h:354
#define JPOOL_IMAGE
Definition: jpeglib.h:749
jpeg_copy_critical_parameters(j_decompress_ptr srcinfo, j_compress_ptr dstinfo)
Definition: jctrans.c:63
compress_output(j_compress_ptr cinfo, JSAMPIMAGE input_buf)
Definition: jctrans.c:278
#define MEMCOPY(dest, src, size)
Definition: jinclude.h:68
#define DCTSIZE2
Definition: jpeglib.h:42
my_coef_controller * my_coef_ptr
Definition: jccoefct.c:57
#define C_MAX_BLOCKS_IN_MCU
Definition: jpeglib.h:55
struct jpeg_destination_mgr * dest
Definition: jpeglib.h:272
JBLOCK FAR * JBLOCKROW
Definition: jpeglib.h:71
GLuint buffer
GLint GLint GLint yoffset
jinit_phuff_encoder(j_compress_ptr cinfo)
Definition: jcphuff.c:814
jzero_far(void FAR *target, size_t bytestozero)
Definition: jutils.c:165
#define FAR
Definition: zconf.h:215
#define JPP(arglist)
Definition: jpeglib.h:818
jinit_huff_encoder(j_compress_ptr cinfo)
Definition: jchuff.c:891
JQUANT_TBL * quant_table
Definition: jpeglib.h:175
JSAMPARRAY * JSAMPIMAGE
Definition: jpeglib.h:68
#define FALSE
Definition: ftobjs.h:57
#define ERREXIT1(cinfo, code, p1)
Definition: jerror.h:208
j_compress_ptr dstinfo
Definition: jpeglib.h:1019
struct jvirt_barray_control * jvirt_barray_ptr
Definition: jpeglib.h:753
jpeg_alloc_quant_table(j_common_ptr cinfo)
Definition: jcomapi.c:86
if(!abbox) return FT_THROW(Invalid_Argument)
#define GLOBAL(type)
Definition: jmorecfg.h:191
#define METHODDEF(type)
Definition: jmorecfg.h:187
jpeg_set_colorspace(j_compress_ptr cinfo, J_COLOR_SPACE colorspace)
Definition: jcparam.c:391
start_iMCU_row(j_compress_ptr cinfo)
Definition: jctrans.c:227
jinit_marker_writer(j_compress_ptr cinfo)
Definition: jcmarker.c:645
J_BUF_MODE
Definition: jpegint.h:16
jinit_c_master_control(j_compress_ptr cinfo, boolean transcode_only)
Definition: jcmaster.c:543
jpeg_set_defaults(j_compress_ptr cinfo)
Definition: jcparam.c:268
unsigned int JDIMENSION
Definition: jmorecfg.h:174
#define CSTATE_WRCOEFS
Definition: jpegint.h:28
#define ERREXIT2(cinfo, code, p1, p2)
Definition: jerror.h:212
boolean int tblno
Definition: jchuff.h:42
#define TRUE
Definition: ftobjs.h:53
#define MAX_COMPS_IN_SCAN
Definition: jpeglib.h:46
LOCAL(void)
Definition: jctrans.c:19