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comparison mupdf-source/thirdparty/libjpeg/jcsample.c @ 2:b50eed0cc0ef upstream

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ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
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1 /*
2 * jcsample.c
3 *
4 * Copyright (C) 1991-1996, Thomas G. Lane.
5 * Modified 2003-2020 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 downsampling routines.
10 *
11 * Downsampling input data is counted in "row groups". A row group
12 * is defined to be max_v_samp_factor pixel rows of each component,
13 * from which the downsampler produces v_samp_factor sample rows.
14 * A single row group is processed in each call to the downsampler module.
15 *
16 * The downsampler is responsible for edge-expansion of its output data
17 * to fill an integral number of DCT blocks horizontally. The source buffer
18 * may be modified if it is helpful for this purpose (the source buffer is
19 * allocated wide enough to correspond to the desired output width).
20 * The caller (the prep controller) is responsible for vertical padding.
21 *
22 * The downsampler may request "context rows" by setting need_context_rows
23 * during startup. In this case, the input arrays will contain at least
24 * one row group's worth of pixels above and below the passed-in data;
25 * the caller will create dummy rows at image top and bottom by replicating
26 * the first or last real pixel row.
27 *
28 * An excellent reference for image resampling is
29 * Digital Image Warping, George Wolberg, 1990.
30 * Pub. by IEEE Computer Society Press, Los Alamitos, CA. ISBN 0-8186-8944-7.
31 *
32 * The downsampling algorithm used here is a simple average of the source
33 * pixels covered by the output pixel. The hi-falutin sampling literature
34 * refers to this as a "box filter". In general the characteristics of a box
35 * filter are not very good, but for the specific cases we normally use (1:1
36 * and 2:1 ratios) the box is equivalent to a "triangle filter" which is not
37 * nearly so bad. If you intend to use other sampling ratios, you'd be well
38 * advised to improve this code.
39 *
40 * A simple input-smoothing capability is provided. This is mainly intended
41 * for cleaning up color-dithered GIF input files (if you find it inadequate,
42 * we suggest using an external filtering program such as pnmconvol). When
43 * enabled, each input pixel P is replaced by a weighted sum of itself and its
44 * eight neighbors. P's weight is 1-8*SF and each neighbor's weight is SF,
45 * where SF = (smoothing_factor / 1024).
46 * Currently, smoothing is only supported for 2h2v sampling factors.
47 */
48
49 #define JPEG_INTERNALS
50 #include "jinclude.h"
51 #include "jpeglib.h"
52
53
54 /* Pointer to routine to downsample a single component */
55 typedef JMETHOD(void, downsample1_ptr,
56 (j_compress_ptr cinfo, jpeg_component_info * compptr,
57 JSAMPARRAY input_data, JSAMPARRAY output_data));
58
59 /* Private subobject */
60
61 typedef struct {
62 struct jpeg_downsampler pub; /* public fields */
63
64 /* Downsampling method pointers, one per component */
65 downsample1_ptr methods[MAX_COMPONENTS];
66
67 /* Height of an output row group for each component. */
68 int rowgroup_height[MAX_COMPONENTS];
69
70 /* These arrays save pixel expansion factors so that int_downsample need not
71 * recompute them each time. They are unused for other downsampling methods.
72 */
73 UINT8 h_expand[MAX_COMPONENTS];
74 UINT8 v_expand[MAX_COMPONENTS];
75 } my_downsampler;
76
77 typedef my_downsampler * my_downsample_ptr;
78
79
80 /*
81 * Initialize for a downsampling pass.
82 */
83
84 METHODDEF(void)
85 start_pass_downsample (j_compress_ptr cinfo)
86 {
87 /* no work for now */
88 }
89
90
91 /*
92 * Expand a component horizontally from width input_cols to width output_cols,
93 * by duplicating the rightmost samples.
94 */
95
96 LOCAL(void)
97 expand_right_edge (JSAMPARRAY image_data, int num_rows,
98 JDIMENSION input_cols, JDIMENSION output_cols)
99 {
100 register JSAMPROW ptr;
101 register JSAMPLE pixval;
102 register int count;
103 int row;
104 int numcols = (int) (output_cols - input_cols);
105
106 if (numcols > 0) {
107 for (row = 0; row < num_rows; row++) {
108 ptr = image_data[row] + input_cols;
109 pixval = ptr[-1]; /* don't need GETJSAMPLE() here */
110 for (count = numcols; count > 0; count--)
111 *ptr++ = pixval;
112 }
113 }
114 }
115
116
117 /*
118 * Do downsampling for a whole row group (all components).
119 *
120 * In this version we simply downsample each component independently.
121 */
122
123 METHODDEF(void)
124 sep_downsample (j_compress_ptr cinfo,
125 JSAMPIMAGE input_buf, JDIMENSION in_row_index,
126 JSAMPIMAGE output_buf, JDIMENSION out_row_group_index)
127 {
128 my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;
129 int ci;
130 jpeg_component_info * compptr;
131 JSAMPARRAY in_ptr, out_ptr;
132
133 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
134 ci++, compptr++) {
135 in_ptr = input_buf[ci] + in_row_index;
136 out_ptr = output_buf[ci] +
137 (out_row_group_index * downsample->rowgroup_height[ci]);
138 (*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr);
139 }
140 }
141
142
143 /*
144 * Downsample pixel values of a single component.
145 * One row group is processed per call.
146 * This version handles arbitrary integral sampling ratios, without smoothing.
147 * Note that this version is not actually used for customary sampling ratios.
148 */
149
150 METHODDEF(void)
151 int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
152 JSAMPARRAY input_data, JSAMPARRAY output_data)
153 {
154 my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;
155 int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v;
156 JDIMENSION outcol, outcol_h; /* outcol_h == outcol*h_expand */
157 JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
158 JSAMPROW inptr, outptr;
159 INT32 outvalue;
160
161 h_expand = downsample->h_expand[compptr->component_index];
162 v_expand = downsample->v_expand[compptr->component_index];
163 numpix = h_expand * v_expand;
164 numpix2 = numpix/2;
165
166 /* Expand input data enough to let all the output samples be generated
167 * by the standard loop. Special-casing padded output would be more
168 * efficient.
169 */
170 expand_right_edge(input_data, cinfo->max_v_samp_factor,
171 cinfo->image_width, output_cols * h_expand);
172
173 inrow = outrow = 0;
174 while (inrow < cinfo->max_v_samp_factor) {
175 outptr = output_data[outrow];
176 for (outcol = 0, outcol_h = 0; outcol < output_cols;
177 outcol++, outcol_h += h_expand) {
178 outvalue = 0;
179 for (v = 0; v < v_expand; v++) {
180 inptr = input_data[inrow+v] + outcol_h;
181 for (h = 0; h < h_expand; h++) {
182 outvalue += (INT32) GETJSAMPLE(*inptr++);
183 }
184 }
185 *outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix);
186 }
187 inrow += v_expand;
188 outrow++;
189 }
190 }
191
192
193 /*
194 * Downsample pixel values of a single component.
195 * This version handles the special case of a full-size component,
196 * without smoothing.
197 */
198
199 METHODDEF(void)
200 fullsize_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
201 JSAMPARRAY input_data, JSAMPARRAY output_data)
202 {
203 /* Copy the data */
204 jcopy_sample_rows(input_data, output_data,
205 cinfo->max_v_samp_factor, cinfo->image_width);
206 /* Edge-expand */
207 expand_right_edge(output_data, cinfo->max_v_samp_factor, cinfo->image_width,
208 compptr->width_in_blocks * compptr->DCT_h_scaled_size);
209 }
210
211
212 /*
213 * Downsample pixel values of a single component.
214 * This version handles the common case of 2:1 horizontal and 1:1 vertical,
215 * without smoothing.
216 *
217 * A note about the "bias" calculations: when rounding fractional values to
218 * integer, we do not want to always round 0.5 up to the next integer.
219 * If we did that, we'd introduce a noticeable bias towards larger values.
220 * Instead, this code is arranged so that 0.5 will be rounded up or down at
221 * alternate pixel locations (a simple ordered dither pattern).
222 */
223
224 METHODDEF(void)
225 h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
226 JSAMPARRAY input_data, JSAMPARRAY output_data)
227 {
228 int inrow;
229 JDIMENSION outcol;
230 JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
231 register JSAMPROW inptr, outptr;
232 register int bias;
233
234 /* Expand input data enough to let all the output samples be generated
235 * by the standard loop. Special-casing padded output would be more
236 * efficient.
237 */
238 expand_right_edge(input_data, cinfo->max_v_samp_factor,
239 cinfo->image_width, output_cols * 2);
240
241 for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {
242 outptr = output_data[inrow];
243 inptr = input_data[inrow];
244 bias = 0; /* bias = 0,1,0,1,... for successive samples */
245 for (outcol = 0; outcol < output_cols; outcol++) {
246 *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1])
247 + bias) >> 1);
248 bias ^= 1; /* 0=>1, 1=>0 */
249 inptr += 2;
250 }
251 }
252 }
253
254
255 /*
256 * Downsample pixel values of a single component.
257 * This version handles the standard case of 2:1 horizontal and 2:1 vertical,
258 * without smoothing.
259 */
260
261 METHODDEF(void)
262 h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
263 JSAMPARRAY input_data, JSAMPARRAY output_data)
264 {
265 int inrow, outrow;
266 JDIMENSION outcol;
267 JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
268 register JSAMPROW inptr0, inptr1, outptr;
269 register int bias;
270
271 /* Expand input data enough to let all the output samples be generated
272 * by the standard loop. Special-casing padded output would be more
273 * efficient.
274 */
275 expand_right_edge(input_data, cinfo->max_v_samp_factor,
276 cinfo->image_width, output_cols * 2);
277
278 inrow = outrow = 0;
279 while (inrow < cinfo->max_v_samp_factor) {
280 outptr = output_data[outrow];
281 inptr0 = input_data[inrow];
282 inptr1 = input_data[inrow+1];
283 bias = 1; /* bias = 1,2,1,2,... for successive samples */
284 for (outcol = 0; outcol < output_cols; outcol++) {
285 *outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
286 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1])
287 + bias) >> 2);
288 bias ^= 3; /* 1=>2, 2=>1 */
289 inptr0 += 2; inptr1 += 2;
290 }
291 inrow += 2;
292 outrow++;
293 }
294 }
295
296
297 #ifdef INPUT_SMOOTHING_SUPPORTED
298
299 /*
300 * Downsample pixel values of a single component.
301 * This version handles the standard case of 2:1 horizontal and 2:1 vertical,
302 * with smoothing. One row of context is required.
303 */
304
305 METHODDEF(void)
306 h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
307 JSAMPARRAY input_data, JSAMPARRAY output_data)
308 {
309 int inrow, outrow;
310 JDIMENSION colctr;
311 JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
312 register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr;
313 INT32 membersum, neighsum, memberscale, neighscale;
314
315 /* Expand input data enough to let all the output samples be generated
316 * by the standard loop. Special-casing padded output would be more
317 * efficient.
318 */
319 expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,
320 cinfo->image_width, output_cols * 2);
321
322 /* We don't bother to form the individual "smoothed" input pixel values;
323 * we can directly compute the output which is the average of the four
324 * smoothed values. Each of the four member pixels contributes a fraction
325 * (1-8*SF) to its own smoothed image and a fraction SF to each of the three
326 * other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final
327 * output. The four corner-adjacent neighbor pixels contribute a fraction
328 * SF to just one smoothed pixel, or SF/4 to the final output; while the
329 * eight edge-adjacent neighbors contribute SF to each of two smoothed
330 * pixels, or SF/2 overall. In order to use integer arithmetic, these
331 * factors are scaled by 2^16 = 65536.
332 * Also recall that SF = smoothing_factor / 1024.
333 */
334
335 memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */
336 neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */
337
338 inrow = outrow = 0;
339 while (inrow < cinfo->max_v_samp_factor) {
340 outptr = output_data[outrow];
341 inptr0 = input_data[inrow];
342 inptr1 = input_data[inrow+1];
343 above_ptr = input_data[inrow-1];
344 below_ptr = input_data[inrow+2];
345
346 /* Special case for first column: pretend column -1 is same as column 0 */
347 membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
348 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
349 neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
350 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
351 GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[2]) +
352 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[2]);
353 neighsum += neighsum;
354 neighsum += GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[2]) +
355 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[2]);
356 membersum = membersum * memberscale + neighsum * neighscale;
357 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
358 inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;
359
360 for (colctr = output_cols - 2; colctr > 0; colctr--) {
361 /* sum of pixels directly mapped to this output element */
362 membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
363 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
364 /* sum of edge-neighbor pixels */
365 neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
366 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
367 GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[2]) +
368 GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[2]);
369 /* The edge-neighbors count twice as much as corner-neighbors */
370 neighsum += neighsum;
371 /* Add in the corner-neighbors */
372 neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[2]) +
373 GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[2]);
374 /* form final output scaled up by 2^16 */
375 membersum = membersum * memberscale + neighsum * neighscale;
376 /* round, descale and output it */
377 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
378 inptr0 += 2; inptr1 += 2; above_ptr += 2; below_ptr += 2;
379 }
380
381 /* Special case for last column */
382 membersum = GETJSAMPLE(*inptr0) + GETJSAMPLE(inptr0[1]) +
383 GETJSAMPLE(*inptr1) + GETJSAMPLE(inptr1[1]);
384 neighsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(above_ptr[1]) +
385 GETJSAMPLE(*below_ptr) + GETJSAMPLE(below_ptr[1]) +
386 GETJSAMPLE(inptr0[-1]) + GETJSAMPLE(inptr0[1]) +
387 GETJSAMPLE(inptr1[-1]) + GETJSAMPLE(inptr1[1]);
388 neighsum += neighsum;
389 neighsum += GETJSAMPLE(above_ptr[-1]) + GETJSAMPLE(above_ptr[1]) +
390 GETJSAMPLE(below_ptr[-1]) + GETJSAMPLE(below_ptr[1]);
391 membersum = membersum * memberscale + neighsum * neighscale;
392 *outptr = (JSAMPLE) ((membersum + 32768) >> 16);
393
394 inrow += 2;
395 outrow++;
396 }
397 }
398
399
400 /*
401 * Downsample pixel values of a single component.
402 * This version handles the special case of a full-size component,
403 * with smoothing. One row of context is required.
404 */
405
406 METHODDEF(void)
407 fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
408 JSAMPARRAY input_data, JSAMPARRAY output_data)
409 {
410 int inrow;
411 JDIMENSION colctr;
412 JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
413 register JSAMPROW inptr, above_ptr, below_ptr, outptr;
414 INT32 membersum, neighsum, memberscale, neighscale;
415 int colsum, lastcolsum, nextcolsum;
416
417 /* Expand input data enough to let all the output samples be generated
418 * by the standard loop. Special-casing padded output would be more
419 * efficient.
420 */
421 expand_right_edge(input_data - 1, cinfo->max_v_samp_factor + 2,
422 cinfo->image_width, output_cols);
423
424 /* Each of the eight neighbor pixels contributes a fraction SF to the
425 * smoothed pixel, while the main pixel contributes (1-8*SF). In order
426 * to use integer arithmetic, these factors are multiplied by 2^16 = 65536.
427 * Also recall that SF = smoothing_factor / 1024.
428 */
429
430 memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */
431 neighscale = cinfo->smoothing_factor * 64; /* scaled SF */
432
433 for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {
434 outptr = output_data[inrow];
435 inptr = input_data[inrow];
436 above_ptr = input_data[inrow-1];
437 below_ptr = input_data[inrow+1];
438
439 /* Special case for first column */
440 colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) +
441 GETJSAMPLE(*inptr);
442 membersum = GETJSAMPLE(*inptr++);
443 nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +
444 GETJSAMPLE(*inptr);
445 neighsum = colsum + (colsum - membersum) + nextcolsum;
446 membersum = membersum * memberscale + neighsum * neighscale;
447 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
448 lastcolsum = colsum; colsum = nextcolsum;
449
450 for (colctr = output_cols - 2; colctr > 0; colctr--) {
451 membersum = GETJSAMPLE(*inptr++);
452 above_ptr++; below_ptr++;
453 nextcolsum = GETJSAMPLE(*above_ptr) + GETJSAMPLE(*below_ptr) +
454 GETJSAMPLE(*inptr);
455 neighsum = lastcolsum + (colsum - membersum) + nextcolsum;
456 membersum = membersum * memberscale + neighsum * neighscale;
457 *outptr++ = (JSAMPLE) ((membersum + 32768) >> 16);
458 lastcolsum = colsum; colsum = nextcolsum;
459 }
460
461 /* Special case for last column */
462 membersum = GETJSAMPLE(*inptr);
463 neighsum = lastcolsum + (colsum - membersum) + colsum;
464 membersum = membersum * memberscale + neighsum * neighscale;
465 *outptr = (JSAMPLE) ((membersum + 32768) >> 16);
466
467 }
468 }
469
470 #endif /* INPUT_SMOOTHING_SUPPORTED */
471
472
473 /*
474 * Module initialization routine for downsampling.
475 * Note that we must select a routine for each component.
476 */
477
478 GLOBAL(void)
479 jinit_downsampler (j_compress_ptr cinfo)
480 {
481 my_downsample_ptr downsample;
482 int ci;
483 jpeg_component_info * compptr;
484 boolean smoothok = TRUE;
485 int h_in_group, v_in_group, h_out_group, v_out_group;
486
487 downsample = (my_downsample_ptr) (*cinfo->mem->alloc_small)
488 ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(my_downsampler));
489 cinfo->downsample = &downsample->pub;
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 }