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jcsample.c
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1 /*
2  * jcsample.c
3  *
4  * Copyright (C) 1991-1996, 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 downsampling routines.
9  *
10  * Downsampling input data is counted in "row groups". A row group
11  * is defined to be max_v_samp_factor pixel rows of each component,
12  * from which the downsampler produces v_samp_factor sample rows.
13  * A single row group is processed in each call to the downsampler module.
14  *
15  * The downsampler is responsible for edge-expansion of its output data
16  * to fill an integral number of DCT blocks horizontally. The source buffer
17  * may be modified if it is helpful for this purpose (the source buffer is
18  * allocated wide enough to correspond to the desired output width).
19  * The caller (the prep controller) is responsible for vertical padding.
20  *
21  * The downsampler may request "context rows" by setting need_context_rows
22  * during startup. In this case, the input arrays will contain at least
23  * one row group's worth of pixels above and below the passed-in data;
24  * the caller will create dummy rows at image top and bottom by replicating
25  * the first or last real pixel row.
26  *
27  * An excellent reference for image resampling is
28  * Digital Image Warping, George Wolberg, 1990.
29  * Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7.
30  *
31  * The downsampling algorithm used here is a simple average of the source
32  * pixels covered by the output pixel. The hi-falutin sampling literature
33  * refers to this as a "box filter". In general the characteristics of a box
34  * filter are not very good, but for the specific cases we normally use (1:1
35  * and 2:1 ratios) the box is equivalent to a "triangle filter" which is not
36  * nearly so bad. If you intend to use other sampling ratios, you'd be well
37  * advised to improve this code.
38  *
39  * A simple input-smoothing capability is provided. This is mainly intended
40  * for cleaning up color-dithered GIF input files (if you find it inadequate,
41  * we suggest using an external filtering program such as pnmconvol). When
42  * enabled, each input pixel P is replaced by a weighted sum of itself and its
43  * eight neighbors. P's weight is 1-8*SF and each neighbor's weight is SF,
44  * where SF = (smoothing_factor / 1024).
45  * Currently, smoothing is only supported for 2h2v sampling factors.
46  */
47 
48 #define JPEG_INTERNALS
49 #include "jinclude.h"
50 #include "jpeglib.h"
51 
52 
53 /* Pointer to routine to downsample a single component */
54 typedef JMETHOD(void, downsample1_ptr,
56  JSAMPARRAY input_data, JSAMPARRAY output_data));
57 
58 /* Private subobject */
59 
60 typedef struct {
61  struct jpeg_downsampler pub; /* public fields */
62 
63  /* Downsampling method pointers, one per component */
64  downsample1_ptr methods[MAX_COMPONENTS];
65 
66  /* Height of an output row group for each component. */
67  int rowgroup_height[MAX_COMPONENTS];
68 
69  /* These arrays save pixel expansion factors so that int_downsample need not
70  * recompute them each time. They are unused for other downsampling methods.
71  */
72  UINT8 h_expand[MAX_COMPONENTS];
73  UINT8 v_expand[MAX_COMPONENTS];
75 
77 
78 
79 /*
80  * Initialize for a downsampling pass.
81  */
82 
83 METHODDEF(void)
85 {
86  /* no work for now */
87 }
88 
89 
90 /*
91  * Expand a component horizontally from width input_cols to width output_cols,
92  * by duplicating the rightmost samples.
93  */
94 
95 LOCAL(void)
97  JDIMENSION input_cols, JDIMENSION output_cols)
98 {
99  register JSAMPROW ptr;
100  register JSAMPLE pixval;
101  register int count;
102  int row;
103  int numcols = (int) (output_cols - input_cols);
104 
105  if (numcols > 0) {
106  for (row = 0; row < num_rows; row++) {
107  ptr = image_data[row] + input_cols;
108  pixval = ptr[-1]; /* don't need GETJSAMPLE() here */
109  for (count = numcols; count > 0; count--)
110  *ptr++ = pixval;
111  }
112  }
113 }
114 
115 
116 /*
117  * Do downsampling for a whole row group (all components).
118  *
119  * In this version we simply downsample each component independently.
120  */
121 
122 METHODDEF(void)
124  JSAMPIMAGE input_buf, JDIMENSION in_row_index,
125  JSAMPIMAGE output_buf, JDIMENSION out_row_group_index)
126 {
127  my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;
128  int ci;
130  JSAMPARRAY in_ptr, out_ptr;
131 
132  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
133  ci++, compptr++) {
134  in_ptr = input_buf[ci] + in_row_index;
135  out_ptr = output_buf[ci] +
136  (out_row_group_index * downsample->rowgroup_height[ci]);
137  (*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr);
138  }
139 }
140 
141 
142 /*
143  * Downsample pixel values of a single component.
144  * One row group is processed per call.
145  * This version handles arbitrary integral sampling ratios, without smoothing.
146  * Note that this version is not actually used for customary sampling ratios.
147  */
148 
149 METHODDEF(void)
151  JSAMPARRAY input_data, JSAMPARRAY output_data)
152 {
153  my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;
154  int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v;
155  JDIMENSION outcol, outcol_h; /* outcol_h == outcol*h_expand */
157  JSAMPROW inptr, outptr;
158  INT32 outvalue;
159 
160  h_expand = downsample->h_expand[compptr->component_index];
161  v_expand = downsample->v_expand[compptr->component_index];
162  numpix = h_expand * v_expand;
163  numpix2 = numpix/2;
164 
165  /* Expand input data enough to let all the output samples be generated
166  * by the standard loop. Special-casing padded output would be more
167  * efficient.
168  */
169  expand_right_edge(input_data, cinfo->max_v_samp_factor,
170  cinfo->image_width, output_cols * h_expand);
171 
172  inrow = outrow = 0;
173  while (inrow < cinfo->max_v_samp_factor) {
174  outptr = output_data[outrow];
175  for (outcol = 0, outcol_h = 0; outcol < output_cols;
176  outcol++, outcol_h += h_expand) {
177  outvalue = 0;
178  for (v = 0; v < v_expand; v++) {
179  inptr = input_data[inrow+v] + outcol_h;
180  for (h = 0; h < h_expand; h++) {
181  outvalue += (INT32) GETJSAMPLE(*inptr++);
182  }
183  }
184  *outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix);
185  }
186  inrow += v_expand;
187  outrow++;
188  }
189 }
190 
191 
192 /*
193  * Downsample pixel values of a single component.
194  * This version handles the special case of a full-size component,
195  * without smoothing.
196  */
197 
198 METHODDEF(void)
200  JSAMPARRAY input_data, JSAMPARRAY output_data)
201 {
202  /* Copy the data */
203  jcopy_sample_rows(input_data, 0, output_data, 0,
204  cinfo->max_v_samp_factor, cinfo->image_width);
205  /* Edge-expand */
206  expand_right_edge(output_data, cinfo->max_v_samp_factor, cinfo->image_width,
208 }
209 
210 
211 /*
212  * Downsample pixel values of a single component.
213  * This version handles the common case of 2:1 horizontal and 1:1 vertical,
214  * without smoothing.
215  *
216  * A note about the "bias" calculations: when rounding fractional values to
217  * integer, we do not want to always round 0.5 up to the next integer.
218  * If we did that, we'd introduce a noticeable bias towards larger values.
219  * Instead, this code is arranged so that 0.5 will be rounded up or down at
220  * alternate pixel locations (a simple ordered dither pattern).
221  */
222 
223 METHODDEF(void)
225  JSAMPARRAY input_data, JSAMPARRAY output_data)
226 {
227  int inrow;
228  JDIMENSION outcol;
230  register JSAMPROW inptr, outptr;
231  register int bias;
232 
233  /* Expand input data enough to let all the output samples be generated
234  * by the standard loop. Special-casing padded output would be more
235  * efficient.
236  */
237  expand_right_edge(input_data, cinfo->max_v_samp_factor,
238  cinfo->image_width, output_cols * 2);
239 
240  for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {
241  outptr = output_data[inrow];
242  inptr = input_data[inrow];
243  bias = 0; /* bias = 0,1,0,1,... for successive samples */
244  for (outcol = 0; outcol < output_cols; outcol++) {
245  *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1])
246  + bias) >> 1);
247  bias ^= 1; /* 0=>1, 1=>0 */
248  inptr += 2;
249  }
250  }
251 }
252 
253 
254 /*
255  * Downsample pixel values of a single component.
256  * This version handles the standard case of 2:1 horizontal and 2:1 vertical,
257  * without smoothing.
258  */
259 
260 METHODDEF(void)
262  JSAMPARRAY input_data, JSAMPARRAY output_data)
263 {
264  int inrow, outrow;
265  JDIMENSION outcol;
267  register JSAMPROW inptr0, inptr1, outptr;
268  register int bias;
269 
270  /* Expand input data enough to let all the output samples be generated
271  * by the standard loop. Special-casing padded output would be more
272  * efficient.
273  */
274  expand_right_edge(input_data, cinfo->max_v_samp_factor,
275  cinfo->image_width, output_cols * 2);
276 
277  inrow = outrow = 0;
278  while (inrow < cinfo->max_v_samp_factor) {
279  outptr = output_data[outrow];
280  inptr0 = input_data[inrow];
281  inptr1 = input_data[inrow+1];
282  bias = 1; /* bias = 1,2,1,2,... for successive samples */
283  for (outcol = 0; outcol < output_cols; outcol++) {
284  *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
285  GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1])
286  + bias) >> 2);
287  bias ^= 3; /* 1=>2, 2=>1 */
288  inptr0 += 2; inptr1 += 2;
289  }
290  inrow += 2;
291  outrow++;
292  }
293 }
294 
295 
296 #ifdef INPUT_SMOOTHING_SUPPORTED
297 
298 /*
299  * Downsample pixel values of a single component.
300  * This version handles the standard case of 2:1 horizontal and 2:1 vertical,
301  * with smoothing. One row of context is required.
302  */
303 
304 METHODDEF(void)
305 h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
306  JSAMPARRAY input_data, JSAMPARRAY output_data)
307 {
308  int inrow, outrow;
309  JDIMENSION colctr;
311  register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr;
312  INT32 membersum, neighsum, memberscale, neighscale;
313 
314  /* Expand input data enough to let all the output samples be generated
315  * by the standard loop. Special-casing padded output would be more
316  * efficient.
317  */
318  expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,
319  cinfo->image_width, output_cols * 2);
320 
321  /* We don't bother to form the individual "smoothed" input pixel values;
322  * we can directly compute the output which is the average of the four
323  * smoothed values. Each of the four member pixels contributes a fraction
324  * (1-8*SF) to its own smoothed image and a fraction SF to each of the three
325  * other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final
326  * output. The four corner-adjacent neighbor pixels contribute a fraction
327  * SF to just one smoothed pixel, or SF/4 to the final output; while the
328  * eight edge-adjacent neighbors contribute SF to each of two smoothed
329  * pixels, or SF/2 overall. In order to use integer arithmetic, these
330  * factors are scaled by 2^16 = 65536.
331  * Also recall that SF = smoothing_factor / 1024.
332  */
333 
334  memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */
335  neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */
336 
337  inrow = outrow = 0;
338  while (inrow < cinfo->max_v_samp_factor) {
339  outptr = output_data[outrow];
340  inptr0 = input_data[inrow];
341  inptr1 = input_data[inrow+1];
342  above_ptr = input_data[inrow-1];
343  below_ptr = input_data[inrow+2];
344 
345  /* Special case for first column: pretend column -1 is same as column 0 */
346  membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
347  GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
348  neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
349  GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
350  GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[2]) +
351  GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[2]);
352  neighsum += neighsum;
353  neighsum += GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[2]) +
354  GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[2]);
355  membersum = membersum * memberscale + neighsum * neighscale;
356  *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
357  inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;
358 
359  for (colctr = output_cols - 2; colctr > 0; colctr--) {
360  /* sum of pixels directly mapped to this output element */
361  membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
362  GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
363  /* sum of edge-neighbor pixels */
364  neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
365  GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
366  GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[2]) +
367  GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[2]);
368  /* The edge-neighbors count twice as much as corner-neighbors */
369  neighsum += neighsum;
370  /* Add in the corner-neighbors */
371  neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[2]) +
372  GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[2]);
373  /* form final output scaled up by 2^16 */
374  membersum = membersum * memberscale + neighsum * neighscale;
375  /* round, descale and output it */
376  *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
377  inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;
378  }
379 
380  /* Special case for last column */
381  membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
382  GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
383  neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
384  GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
385  GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[1]) +
386  GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[1]);
387  neighsum += neighsum;
388  neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[1]) +
389  GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[1]);
390  membersum = membersum * memberscale + neighsum * neighscale;
391  *outptr = (JSAMPLE) ((membersum + 32768) >> 16);
392 
393  inrow += 2;
394  outrow++;
395  }
396 }
397 
398 
399 /*
400  * Downsample pixel values of a single component.
401  * This version handles the special case of a full-size component,
402  * with smoothing. One row of context is required.
403  */
404 
405 METHODDEF(void)
406 fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
407  JSAMPARRAY input_data, JSAMPARRAY output_data)
408 {
409  int inrow;
410  JDIMENSION colctr;
412  register JSAMPROW inptr, above_ptr, below_ptr, outptr;
413  INT32 membersum, neighsum, memberscale, neighscale;
414  int colsum, lastcolsum, nextcolsum;
415 
416  /* Expand input data enough to let all the output samples be generated
417  * by the standard loop. Special-casing padded output would be more
418  * efficient.
419  */
420  expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,
421  cinfo->image_width, output_cols);
422 
423  /* Each of the eight neighbor pixels contributes a fraction SF to the
424  * smoothed pixel, while the main pixel contributes (1-8*SF). In order
425  * to use integer arithmetic, these factors are multiplied by 2^16 = 65536.
426  * Also recall that SF = smoothing_factor / 1024.
427  */
428 
429  memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */
430  neighscale = cinfo->smoothing_factor * 64; /* scaled SF */
431 
432  for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {
433  outptr = output_data[inrow];
434  inptr = input_data[inrow];
435  above_ptr = input_data[inrow-1];
436  below_ptr = input_data[inrow+1];
437 
438  /* Special case for first column */
439  colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) +
440  GETJSAMPLE(*inptr);
441  membersum = GETJSAMPLE(*inptr++);
442  nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +
443  GETJSAMPLE(*inptr);
444  neighsum = colsum + (colsum - membersum) + nextcolsum;
445  membersum = membersum * memberscale + neighsum * neighscale;
446  *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
447  lastcolsum = colsum; colsum = nextcolsum;
448 
449  for (colctr = output_cols - 2; colctr > 0; colctr--) {
450  membersum = GETJSAMPLE(*inptr++);
451  above_ptr++; below_ptr++;
452  nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +
453  GETJSAMPLE(*inptr);
454  neighsum = lastcolsum + (colsum - membersum) + nextcolsum;
455  membersum = membersum * memberscale + neighsum * neighscale;
456  *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
457  lastcolsum = colsum; colsum = nextcolsum;
458  }
459 
460  /* Special case for last column */
461  membersum = GETJSAMPLE(*inptr);
462  neighsum = lastcolsum + (colsum - membersum) + colsum;
463  membersum = membersum * memberscale + neighsum * neighscale;
464  *outptr = (JSAMPLE) ((membersum + 32768) >> 16);
465 
466  }
467 }
468 
469 #endif /* INPUT_SMOOTHING_SUPPORTED */
470 
471 
472 /*
473  * Module initialization routine for downsampling.
474  * Note that we must select a routine for each component.
475  */
476 
477 GLOBAL(void)
479 {
480  my_downsample_ptr downsample;
481  int ci;
483  boolean smoothok = TRUE;
484  int h_in_group, v_in_group, h_out_group, v_out_group;
485 
486  downsample = (my_downsample_ptr)
487  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
489  cinfo->downsample = (struct jpeg_downsampler *) downsample;
490  downsample->pub.start_pass = start_pass_downsample;
491  downsample->pub.downsample = sep_downsample;
492  downsample->pub.need_context_rows = FALSE;
493 
494  if (cinfo->CCIR601_sampling)
495  ERREXIT(cinfo, JERR_CCIR601_NOTIMPL);
496 
497  /* Verify we can handle the sampling factors, and set up method pointers */
498  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
499  ci++, compptr++) {
500  /* Compute size of an "output group" for DCT scaling. This many samples
501  * are to be converted from max_h_samp_factor * max_v_samp_factor pixels.
502  */
503  h_out_group = (compptr->h_samp_factor * compptr->DCT_h_scaled_size) /
504  cinfo->min_DCT_h_scaled_size;
505  v_out_group = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
506  cinfo->min_DCT_v_scaled_size;
507  h_in_group = cinfo->max_h_samp_factor;
508  v_in_group = cinfo->max_v_samp_factor;
509  downsample->rowgroup_height[ci] = v_out_group; /* save for use later */
510  if (h_in_group == h_out_group && v_in_group == v_out_group) {
511 #ifdef INPUT_SMOOTHING_SUPPORTED
512  if (cinfo->smoothing_factor) {
513  downsample->methods[ci] = fullsize_smooth_downsample;
514  downsample->pub.need_context_rows = TRUE;
515  } else
516 #endif
517  downsample->methods[ci] = fullsize_downsample;
518  } else if (h_in_group == h_out_group * 2 &&
519  v_in_group == v_out_group) {
520  smoothok = FALSE;
521  downsample->methods[ci] = h2v1_downsample;
522  } else if (h_in_group == h_out_group * 2 &&
523  v_in_group == v_out_group * 2) {
524 #ifdef INPUT_SMOOTHING_SUPPORTED
525  if (cinfo->smoothing_factor) {
526  downsample->methods[ci] = h2v2_smooth_downsample;
527  downsample->pub.need_context_rows = TRUE;
528  } else
529 #endif
530  downsample->methods[ci] = h2v2_downsample;
531  } else if ((h_in_group % h_out_group) == 0 &&
532  (v_in_group % v_out_group) == 0) {
533  smoothok = FALSE;
534  downsample->methods[ci] = int_downsample;
535  downsample->h_expand[ci] = (UINT8) (h_in_group / h_out_group);
536  downsample->v_expand[ci] = (UINT8) (v_in_group / v_out_group);
537  } else
538  ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL);
539  }
540 
541 #ifdef INPUT_SMOOTHING_SUPPORTED
542  if (cinfo->smoothing_factor && !smoothok)
543  TRACEMS(cinfo, 0, JTRC_SMOOTH_NOTIMPL);
544 #endif
545 }
#define TRUE
Definition: types.h:120
char JSAMPLE
Definition: jmorecfg.h:74
typedef JMETHOD(void, downsample1_ptr,(j_compress_ptr cinfo, jpeg_component_info *compptr, JSAMPARRAY input_data, JSAMPARRAY output_data))
JSAMPLE FAR * JSAMPROW
Definition: jpeglib.h:75
#define ERREXIT(msg)
Definition: rdjpgcom.c:72
h2v1_downsample(j_compress_ptr cinfo, jpeg_component_info *compptr, JSAMPARRAY input_data, JSAMPARRAY output_data)
Definition: jcsample.c:224
fullsize_downsample(j_compress_ptr cinfo, jpeg_component_info *compptr, JSAMPARRAY input_data, JSAMPARRAY output_data)
Definition: jcsample.c:199
UINT8 h_expand[MAX_COMPONENTS]
Definition: jcsample.c:72
GLuint GLuint GLsizei count
Definition: gl.h:1545
struct jpeg_common_struct * j_common_ptr
Definition: jpeglib.h:284
#define MAX_COMPONENTS
Definition: jmorecfg.h:45
#define GETJSAMPLE(value)
Definition: jmorecfg.h:78
expand_right_edge(JSAMPARRAY image_data, int num_rows, JDIMENSION input_cols, JDIMENSION output_cols)
Definition: jcsample.c:96
GLfloat GLfloat GLfloat GLfloat h
Definition: glext.h:7723
jpeg_component_info * compptr
Definition: jdct.h:238
JDIMENSION width_in_blocks
Definition: jpeglib.h:148
#define TRACEMS(cinfo, lvl, code)
Definition: jerror.h:265
#define SIZEOF(_ar)
Definition: calc.h:97
#define JPOOL_IMAGE
Definition: jpeglib.h:808
h2v2_downsample(j_compress_ptr cinfo, jpeg_component_info *compptr, JSAMPARRAY input_data, JSAMPARRAY output_data)
Definition: jcsample.c:261
static PVOID ptr
Definition: dispmode.c:27
GLfloat bias
Definition: glext.h:7909
int_downsample(j_compress_ptr cinfo, jpeg_component_info *compptr, JSAMPARRAY input_data, JSAMPARRAY output_data)
Definition: jcsample.c:150
int rowgroup_height[MAX_COMPONENTS]
Definition: jcsample.c:67
my_downsampler * my_downsample_ptr
Definition: jcsample.c:76
#define LOCAL(type)
Definition: jmorecfg.h:289
jinit_downsampler(j_compress_ptr cinfo)
Definition: jcsample.c:478
UINT8 v_expand[MAX_COMPONENTS]
Definition: jcsample.c:73
int JSAMPARRAY int int num_rows
Definition: jpegint.h:412
#define for
Definition: utility.h:88
JSAMPARRAY * JSAMPIMAGE
Definition: jpeglib.h:77
static const WCHAR L[]
Definition: oid.c:1250
struct jpeg_downsampler pub
Definition: jcsample.c:61
sep_downsample(j_compress_ptr cinfo, JSAMPIMAGE input_buf, JDIMENSION in_row_index, JSAMPIMAGE output_buf, JDIMENSION out_row_group_index)
Definition: jcsample.c:123
JSAMPROW * JSAMPARRAY
Definition: jpeglib.h:76
#define GLOBAL(type)
Definition: jmorecfg.h:291
#define METHODDEF(type)
Definition: jmorecfg.h:287
const GLdouble * v
Definition: gl.h:2040
start_pass_downsample(j_compress_ptr cinfo)
Definition: jcsample.c:84
downsample1_ptr methods[MAX_COMPONENTS]
Definition: jcsample.c:64
jpeg_component_info JCOEFPTR JSAMPARRAY output_buf
Definition: jdct.h:238
unsigned int JDIMENSION
Definition: jmorecfg.h:229
signed int INT32
jcopy_sample_rows(JSAMPARRAY input_array, int source_row, JSAMPARRAY output_array, int dest_row, int num_rows, JDIMENSION num_cols)
Definition: jutils.c:177
unsigned char UINT8
struct png_info_def *typedef unsigned char **typedef struct png_info_def *typedef struct png_info_def *typedef struct png_info_def *typedef unsigned char ** row
Definition: typeof.h:78
unsigned int(__cdecl typeof(jpeg_read_scanlines))(struct jpeg_decompress_struct *
Definition: typeof.h:31
JDIMENSION image_width
Definition: jpeglib.h:302