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