1 /*
2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 /****************************************************************************
12 *
13 * Module Title : scale.c
14 *
15 * Description : Image scaling functions.
16 *
17 ***************************************************************************/
18
19 /****************************************************************************
20 * Header Files
21 ****************************************************************************/
22 #include <assert.h>
23
24 #include "./vpx_scale_rtcd.h"
25 #include "vpx_mem/vpx_mem.h"
26 #include "vpx_scale/vpx_scale.h"
27 #include "vpx_scale/yv12config.h"
28
29 typedef struct {
30 int expanded_frame_width;
31 int expanded_frame_height;
32
33 int HScale;
34 int HRatio;
35 int VScale;
36 int VRatio;
37
38 YV12_BUFFER_CONFIG *src_yuv_config;
39 YV12_BUFFER_CONFIG *dst_yuv_config;
40
41 } SCALE_VARS;
42
43 /****************************************************************************
44 *
45 * ROUTINE : scale1d_2t1_i
46 *
47 * INPUTS : const unsigned char *source : Pointer to data to be scaled.
48 * int source_step : Number of pixels to step on in
49 * source.
50 * unsigned int source_scale : Scale for source (UNUSED).
51 * unsigned int source_length : Length of source (UNUSED).
52 * unsigned char *dest : Pointer to output data array.
53 * int dest_step : Number of pixels to step on in
54 * destination.
55 * unsigned int dest_scale : Scale for destination
56 * (UNUSED).
57 * unsigned int dest_length : Length of destination.
58 *
59 * OUTPUTS : None.
60 *
61 * RETURNS : void
62 *
63 * FUNCTION : Performs 2-to-1 interpolated scaling.
64 *
65 * SPECIAL NOTES : None.
66 *
67 ****************************************************************************/
scale1d_2t1_i(const unsigned char * source,int source_step,unsigned int source_scale,unsigned int source_length,unsigned char * dest,int dest_step,unsigned int dest_scale,unsigned int dest_length)68 static void scale1d_2t1_i(const unsigned char *source, int source_step,
69 unsigned int source_scale, unsigned int source_length,
70 unsigned char *dest, int dest_step,
71 unsigned int dest_scale, unsigned int dest_length) {
72 unsigned int i, j;
73 unsigned int temp;
74 int source_pitch = source_step;
75 (void)source_length;
76 (void)source_scale;
77 (void)dest_scale;
78
79 source_step *= 2;
80 dest[0] = source[0];
81
82 for (i = dest_step, j = source_step; i < dest_length * dest_step;
83 i += dest_step, j += source_step) {
84 temp = 8;
85 temp += 3 * source[j - source_pitch];
86 temp += 10 * source[j];
87 temp += 3 * source[j + source_pitch];
88 temp >>= 4;
89 dest[i] = (char)(temp);
90 }
91 }
92
93 /****************************************************************************
94 *
95 * ROUTINE : scale1d_2t1_ps
96 *
97 * INPUTS : const unsigned char *source : Pointer to data to be scaled.
98 * int source_step : Number of pixels to step on in
99 * source.
100 * unsigned int source_scale : Scale for source (UNUSED).
101 * unsigned int source_length : Length of source (UNUSED).
102 * unsigned char *dest : Pointer to output data array.
103 * int dest_step : Number of pixels to step on in
104 * destination.
105 * unsigned int dest_scale : Scale for destination
106 * (UNUSED).
107 * unsigned int dest_length : Length of destination.
108 *
109 * OUTPUTS : None.
110 *
111 * RETURNS : void
112 *
113 * FUNCTION : Performs 2-to-1 point subsampled scaling.
114 *
115 * SPECIAL NOTES : None.
116 *
117 ****************************************************************************/
scale1d_2t1_ps(const unsigned char * source,int source_step,unsigned int source_scale,unsigned int source_length,unsigned char * dest,int dest_step,unsigned int dest_scale,unsigned int dest_length)118 static void scale1d_2t1_ps(const unsigned char *source, int source_step,
119 unsigned int source_scale,
120 unsigned int source_length, unsigned char *dest,
121 int dest_step, unsigned int dest_scale,
122 unsigned int dest_length) {
123 unsigned int i, j;
124
125 (void)source_length;
126 (void)source_scale;
127 (void)dest_scale;
128
129 source_step *= 2;
130 j = 0;
131
132 for (i = 0; i < dest_length * dest_step; i += dest_step, j += source_step)
133 dest[i] = source[j];
134 }
135 /****************************************************************************
136 *
137 * ROUTINE : scale1d_c
138 *
139 * INPUTS : const unsigned char *source : Pointer to data to be scaled.
140 * int source_step : Number of pixels to step on in
141 * source.
142 * unsigned int source_scale : Scale for source.
143 * unsigned int source_length : Length of source (UNUSED).
144 * unsigned char *dest : Pointer to output data array.
145 * int dest_step : Number of pixels to step on in
146 * destination.
147 * unsigned int dest_scale : Scale for destination.
148 * unsigned int dest_length : Length of destination.
149 *
150 * OUTPUTS : None.
151 *
152 * RETURNS : void
153 *
154 * FUNCTION : Performs linear interpolation in one dimension.
155 *
156 * SPECIAL NOTES : None.
157 *
158 ****************************************************************************/
scale1d_c(const unsigned char * source,int source_step,unsigned int source_scale,unsigned int source_length,unsigned char * dest,int dest_step,unsigned int dest_scale,unsigned int dest_length)159 static void scale1d_c(const unsigned char *source, int source_step,
160 unsigned int source_scale, unsigned int source_length,
161 unsigned char *dest, int dest_step,
162 unsigned int dest_scale, unsigned int dest_length) {
163 unsigned int i;
164 unsigned int round_value = dest_scale / 2;
165 unsigned int left_modifier = dest_scale;
166 unsigned int right_modifier = 0;
167 unsigned char left_pixel = *source;
168 unsigned char right_pixel = *(source + source_step);
169
170 (void)source_length;
171
172 /* These asserts are needed if there are boundary issues... */
173 /*assert ( dest_scale > source_scale );*/
174 /*assert ( (source_length-1) * dest_scale >= (dest_length-1) * source_scale
175 * );*/
176
177 assert(dest_scale != 0);
178 for (i = 0; i < dest_length * dest_step; i += dest_step) {
179 dest[i] = (char)((left_modifier * left_pixel +
180 right_modifier * right_pixel + round_value) /
181 dest_scale);
182
183 right_modifier += source_scale;
184
185 while (right_modifier > dest_scale) {
186 right_modifier -= dest_scale;
187 source += source_step;
188 left_pixel = *source;
189 right_pixel = *(source + source_step);
190 }
191
192 left_modifier = dest_scale - right_modifier;
193 }
194 }
195
196 /****************************************************************************
197 *
198 * ROUTINE : Scale2D
199 *
200 * INPUTS : const unsigned char *source : Pointer to data to be
201 * scaled.
202 * int source_pitch : Stride of source image.
203 * unsigned int source_width : Width of input image.
204 * unsigned int source_height : Height of input image.
205 * unsigned char *dest : Pointer to output data
206 * array.
207 * int dest_pitch : Stride of destination
208 * image.
209 * unsigned int dest_width : Width of destination image.
210 * unsigned int dest_height : Height of destination
211 * image.
212 * unsigned char *temp_area : Pointer to temp work area.
213 * unsigned char temp_area_height : Height of temp work area.
214 * unsigned int hscale : Horizontal scale factor
215 * numerator.
216 * unsigned int hratio : Horizontal scale factor
217 * denominator.
218 * unsigned int vscale : Vertical scale factor
219 * numerator.
220 * unsigned int vratio : Vertical scale factor
221 * denominator.
222 * unsigned int interlaced : Interlace flag.
223 *
224 * OUTPUTS : None.
225 *
226 * RETURNS : void
227 *
228 * FUNCTION : Performs 2-tap linear interpolation in two dimensions.
229 *
230 * SPECIAL NOTES : Expansion is performed one band at a time to help with
231 * caching.
232 *
233 ****************************************************************************/
Scale2D(unsigned char * source,int source_pitch,unsigned int source_width,unsigned int source_height,unsigned char * dest,int dest_pitch,unsigned int dest_width,unsigned int dest_height,unsigned char * temp_area,unsigned char temp_area_height,unsigned int hscale,unsigned int hratio,unsigned int vscale,unsigned int vratio,unsigned int interlaced)234 static void Scale2D(
235 /*const*/
236 unsigned char *source, int source_pitch, unsigned int source_width,
237 unsigned int source_height, unsigned char *dest, int dest_pitch,
238 unsigned int dest_width, unsigned int dest_height, unsigned char *temp_area,
239 unsigned char temp_area_height, unsigned int hscale, unsigned int hratio,
240 unsigned int vscale, unsigned int vratio, unsigned int interlaced) {
241 /*unsigned*/
242 int i, j, k;
243 int bands;
244 int dest_band_height;
245 int source_band_height;
246
247 typedef void (*Scale1D)(const unsigned char *source, int source_step,
248 unsigned int source_scale, unsigned int source_length,
249 unsigned char *dest, int dest_step,
250 unsigned int dest_scale, unsigned int dest_length);
251
252 Scale1D Scale1Dv = scale1d_c;
253 Scale1D Scale1Dh = scale1d_c;
254
255 void (*horiz_line_scale)(const unsigned char *, unsigned int, unsigned char *,
256 unsigned int) = NULL;
257 void (*vert_band_scale)(unsigned char *, unsigned int, unsigned char *,
258 unsigned int, unsigned int) = NULL;
259
260 int ratio_scalable = 1;
261 int interpolation = 0;
262
263 unsigned char *source_base;
264 unsigned char *line_src;
265
266 source_base = (unsigned char *)source;
267
268 if (source_pitch < 0) {
269 int offset;
270
271 offset = (source_height - 1);
272 offset *= source_pitch;
273
274 source_base += offset;
275 }
276
277 /* find out the ratio for each direction */
278 switch (hratio * 10 / hscale) {
279 case 8:
280 /* 4-5 Scale in Width direction */
281 horiz_line_scale = vp8_horizontal_line_5_4_scale;
282 break;
283 case 6:
284 /* 3-5 Scale in Width direction */
285 horiz_line_scale = vp8_horizontal_line_5_3_scale;
286 break;
287 case 5:
288 /* 1-2 Scale in Width direction */
289 horiz_line_scale = vp8_horizontal_line_2_1_scale;
290 break;
291 default:
292 /* The ratio is not acceptable now */
293 /* throw("The ratio is not acceptable for now!"); */
294 ratio_scalable = 0;
295 break;
296 }
297
298 switch (vratio * 10 / vscale) {
299 case 8:
300 /* 4-5 Scale in vertical direction */
301 vert_band_scale = vp8_vertical_band_5_4_scale;
302 source_band_height = 5;
303 dest_band_height = 4;
304 break;
305 case 6:
306 /* 3-5 Scale in vertical direction */
307 vert_band_scale = vp8_vertical_band_5_3_scale;
308 source_band_height = 5;
309 dest_band_height = 3;
310 break;
311 case 5:
312 /* 1-2 Scale in vertical direction */
313
314 if (interlaced) {
315 /* if the content is interlaced, point sampling is used */
316 vert_band_scale = vp8_vertical_band_2_1_scale;
317 } else {
318 interpolation = 1;
319 /* if the content is progressive, interplo */
320 vert_band_scale = vp8_vertical_band_2_1_scale_i;
321 }
322
323 source_band_height = 2;
324 dest_band_height = 1;
325 break;
326 default:
327 /* The ratio is not acceptable now */
328 /* throw("The ratio is not acceptable for now!"); */
329 ratio_scalable = 0;
330 break;
331 }
332
333 if (ratio_scalable) {
334 if (source_height == dest_height) {
335 /* for each band of the image */
336 for (k = 0; k < (int)dest_height; k++) {
337 horiz_line_scale(source, source_width, dest, dest_width);
338 source += source_pitch;
339 dest += dest_pitch;
340 }
341
342 return;
343 }
344
345 if (interpolation) {
346 if (source < source_base) source = source_base;
347
348 horiz_line_scale(source, source_width, temp_area, dest_width);
349 }
350
351 for (k = 0;
352 k < (int)(dest_height + dest_band_height - 1) / dest_band_height;
353 k++) {
354 /* scale one band horizontally */
355 for (i = 0; i < source_band_height; i++) {
356 /* Trap case where we could read off the base of the source buffer */
357
358 line_src = (unsigned char *)source + i * source_pitch;
359
360 if (line_src < source_base) line_src = source_base;
361
362 horiz_line_scale(line_src, source_width,
363 temp_area + (i + 1) * dest_pitch, dest_width);
364 }
365
366 /* Vertical scaling is in place */
367 vert_band_scale(temp_area + dest_pitch, dest_pitch, dest, dest_pitch,
368 dest_width);
369
370 if (interpolation)
371 memcpy(temp_area, temp_area + source_band_height * dest_pitch,
372 dest_width);
373
374 /* Next band... */
375 source += (unsigned long)source_band_height * source_pitch;
376 dest += (unsigned long)dest_band_height * dest_pitch;
377 }
378
379 return;
380 }
381
382 if (hscale == 2 && hratio == 1) Scale1Dh = scale1d_2t1_ps;
383
384 if (vscale == 2 && vratio == 1) {
385 if (interlaced)
386 Scale1Dv = scale1d_2t1_ps;
387 else
388 Scale1Dv = scale1d_2t1_i;
389 }
390
391 if (source_height == dest_height) {
392 /* for each band of the image */
393 for (k = 0; k < (int)dest_height; k++) {
394 Scale1Dh(source, 1, hscale, source_width + 1, dest, 1, hratio,
395 dest_width);
396 source += source_pitch;
397 dest += dest_pitch;
398 }
399
400 return;
401 }
402
403 if (dest_height > source_height) {
404 dest_band_height = temp_area_height - 1;
405 source_band_height = dest_band_height * source_height / dest_height;
406 } else {
407 source_band_height = temp_area_height - 1;
408 dest_band_height = source_band_height * vratio / vscale;
409 }
410
411 /* first row needs to be done so that we can stay one row ahead for vertical
412 * zoom */
413 Scale1Dh(source, 1, hscale, source_width + 1, temp_area, 1, hratio,
414 dest_width);
415
416 /* for each band of the image */
417 bands = (dest_height + dest_band_height - 1) / dest_band_height;
418
419 for (k = 0; k < bands; k++) {
420 /* scale one band horizontally */
421 for (i = 1; i < source_band_height + 1; i++) {
422 if (k * source_band_height + i < (int)source_height) {
423 Scale1Dh(source + i * source_pitch, 1, hscale, source_width + 1,
424 temp_area + i * dest_pitch, 1, hratio, dest_width);
425 } else { /* Duplicate the last row */
426 /* copy temp_area row 0 over from last row in the past */
427 memcpy(temp_area + i * dest_pitch, temp_area + (i - 1) * dest_pitch,
428 dest_pitch);
429 }
430 }
431
432 /* scale one band vertically */
433 for (j = 0; j < (int)dest_width; j++) {
434 Scale1Dv(&temp_area[j], dest_pitch, vscale, source_band_height + 1,
435 &dest[j], dest_pitch, vratio, dest_band_height);
436 }
437
438 /* copy temp_area row 0 over from last row in the past */
439 memcpy(temp_area, temp_area + source_band_height * dest_pitch, dest_pitch);
440
441 /* move to the next band */
442 source += source_band_height * source_pitch;
443 dest += dest_band_height * dest_pitch;
444 }
445 }
446
447 /****************************************************************************
448 *
449 * ROUTINE : vpx_scale_frame
450 *
451 * INPUTS : YV12_BUFFER_CONFIG *src : Pointer to frame to be
452 * scaled.
453 * YV12_BUFFER_CONFIG *dst : Pointer to buffer to hold
454 * scaled frame.
455 * unsigned char *temp_area : Pointer to temp work area.
456 * unsigned char temp_area_height : Height of temp work area.
457 * unsigned int hscale : Horizontal scale factor
458 * numerator.
459 * unsigned int hratio : Horizontal scale factor
460 * denominator.
461 * unsigned int vscale : Vertical scale factor
462 * numerator.
463 * unsigned int vratio : Vertical scale factor
464 * denominator.
465 * unsigned int interlaced : Interlace flag.
466 *
467 * OUTPUTS : None.
468 *
469 * RETURNS : void
470 *
471 * FUNCTION : Performs 2-tap linear interpolation in two dimensions.
472 *
473 * SPECIAL NOTES : Expansion is performed one band at a time to help with
474 * caching.
475 *
476 ****************************************************************************/
vpx_scale_frame(YV12_BUFFER_CONFIG * src,YV12_BUFFER_CONFIG * dst,unsigned char * temp_area,unsigned char temp_height,unsigned int hscale,unsigned int hratio,unsigned int vscale,unsigned int vratio,unsigned int interlaced)477 void vpx_scale_frame(YV12_BUFFER_CONFIG *src, YV12_BUFFER_CONFIG *dst,
478 unsigned char *temp_area, unsigned char temp_height,
479 unsigned int hscale, unsigned int hratio,
480 unsigned int vscale, unsigned int vratio,
481 unsigned int interlaced) {
482 int i;
483 int dw = (hscale - 1 + src->y_width * hratio) / hscale;
484 int dh = (vscale - 1 + src->y_height * vratio) / vscale;
485
486 /* call our internal scaling routines!! */
487 Scale2D((unsigned char *)src->y_buffer, src->y_stride, src->y_width,
488 src->y_height, (unsigned char *)dst->y_buffer, dst->y_stride, dw, dh,
489 temp_area, temp_height, hscale, hratio, vscale, vratio, interlaced);
490
491 if (dw < (int)dst->y_width)
492 for (i = 0; i < dh; i++)
493 memset(dst->y_buffer + i * dst->y_stride + dw - 1,
494 dst->y_buffer[i * dst->y_stride + dw - 2], dst->y_width - dw + 1);
495
496 if (dh < (int)dst->y_height)
497 for (i = dh - 1; i < (int)dst->y_height; i++)
498 memcpy(dst->y_buffer + i * dst->y_stride,
499 dst->y_buffer + (dh - 2) * dst->y_stride, dst->y_width + 1);
500
501 Scale2D((unsigned char *)src->u_buffer, src->uv_stride, src->uv_width,
502 src->uv_height, (unsigned char *)dst->u_buffer, dst->uv_stride,
503 dw / 2, dh / 2, temp_area, temp_height, hscale, hratio, vscale,
504 vratio, interlaced);
505
506 if (dw / 2 < (int)dst->uv_width)
507 for (i = 0; i < dst->uv_height; i++)
508 memset(dst->u_buffer + i * dst->uv_stride + dw / 2 - 1,
509 dst->u_buffer[i * dst->uv_stride + dw / 2 - 2],
510 dst->uv_width - dw / 2 + 1);
511
512 if (dh / 2 < (int)dst->uv_height)
513 for (i = dh / 2 - 1; i < (int)dst->y_height / 2; i++)
514 memcpy(dst->u_buffer + i * dst->uv_stride,
515 dst->u_buffer + (dh / 2 - 2) * dst->uv_stride, dst->uv_width);
516
517 Scale2D((unsigned char *)src->v_buffer, src->uv_stride, src->uv_width,
518 src->uv_height, (unsigned char *)dst->v_buffer, dst->uv_stride,
519 dw / 2, dh / 2, temp_area, temp_height, hscale, hratio, vscale,
520 vratio, interlaced);
521
522 if (dw / 2 < (int)dst->uv_width)
523 for (i = 0; i < dst->uv_height; i++)
524 memset(dst->v_buffer + i * dst->uv_stride + dw / 2 - 1,
525 dst->v_buffer[i * dst->uv_stride + dw / 2 - 2],
526 dst->uv_width - dw / 2 + 1);
527
528 if (dh / 2 < (int)dst->uv_height)
529 for (i = dh / 2 - 1; i < (int)dst->y_height / 2; i++)
530 memcpy(dst->v_buffer + i * dst->uv_stride,
531 dst->v_buffer + (dh / 2 - 2) * dst->uv_stride, dst->uv_width);
532 }
533