1 /*
2  *  Copyright (c) 2013 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 #include "./vpx_dsp_rtcd.h"
12 #include "vp9/common/vp9_filter.h"
13 #include "vp9/common/vp9_scale.h"
14 #include "vpx_dsp/vpx_filter.h"
15 
scaled_x(int val,const struct scale_factors * sf)16 static INLINE int scaled_x(int val, const struct scale_factors *sf) {
17   return (int)((int64_t)val * sf->x_scale_fp >> REF_SCALE_SHIFT);
18 }
19 
scaled_y(int val,const struct scale_factors * sf)20 static INLINE int scaled_y(int val, const struct scale_factors *sf) {
21   return (int)((int64_t)val * sf->y_scale_fp >> REF_SCALE_SHIFT);
22 }
23 
unscaled_value(int val,const struct scale_factors * sf)24 static int unscaled_value(int val, const struct scale_factors *sf) {
25   (void)sf;
26   return val;
27 }
28 
get_fixed_point_scale_factor(int other_size,int this_size)29 static int get_fixed_point_scale_factor(int other_size, int this_size) {
30   // Calculate scaling factor once for each reference frame
31   // and use fixed point scaling factors in decoding and encoding routines.
32   // Hardware implementations can calculate scale factor in device driver
33   // and use multiplication and shifting on hardware instead of division.
34   return (other_size << REF_SCALE_SHIFT) / this_size;
35 }
36 
vp9_scale_mv(const MV * mv,int x,int y,const struct scale_factors * sf)37 MV32 vp9_scale_mv(const MV *mv, int x, int y, const struct scale_factors *sf) {
38   const int x_off_q4 = scaled_x(x << SUBPEL_BITS, sf) & SUBPEL_MASK;
39   const int y_off_q4 = scaled_y(y << SUBPEL_BITS, sf) & SUBPEL_MASK;
40   const MV32 res = { scaled_y(mv->row, sf) + y_off_q4,
41                      scaled_x(mv->col, sf) + x_off_q4 };
42   return res;
43 }
44 
45 #if CONFIG_VP9_HIGHBITDEPTH
vp9_setup_scale_factors_for_frame(struct scale_factors * sf,int other_w,int other_h,int this_w,int this_h,int use_highbd)46 void vp9_setup_scale_factors_for_frame(struct scale_factors *sf, int other_w,
47                                        int other_h, int this_w, int this_h,
48                                        int use_highbd) {
49 #else
50 void vp9_setup_scale_factors_for_frame(struct scale_factors *sf, int other_w,
51                                        int other_h, int this_w, int this_h) {
52 #endif
53   if (!valid_ref_frame_size(other_w, other_h, this_w, this_h)) {
54     sf->x_scale_fp = REF_INVALID_SCALE;
55     sf->y_scale_fp = REF_INVALID_SCALE;
56     return;
57   }
58 
59   sf->x_scale_fp = get_fixed_point_scale_factor(other_w, this_w);
60   sf->y_scale_fp = get_fixed_point_scale_factor(other_h, this_h);
61   sf->x_step_q4 = scaled_x(16, sf);
62   sf->y_step_q4 = scaled_y(16, sf);
63 
64   if (vp9_is_scaled(sf)) {
65     sf->scale_value_x = scaled_x;
66     sf->scale_value_y = scaled_y;
67   } else {
68     sf->scale_value_x = unscaled_value;
69     sf->scale_value_y = unscaled_value;
70   }
71 
72   // TODO(agrange): Investigate the best choice of functions to use here
73   // for EIGHTTAP_SMOOTH. Since it is not interpolating, need to choose what
74   // to do at full-pel offsets. The current selection, where the filter is
75   // applied in one direction only, and not at all for 0,0, seems to give the
76   // best quality, but it may be worth trying an additional mode that does
77   // do the filtering on full-pel.
78 
79   if (sf->x_step_q4 == 16) {
80     if (sf->y_step_q4 == 16) {
81       // No scaling in either direction.
82       sf->predict[0][0][0] = vpx_convolve_copy;
83       sf->predict[0][0][1] = vpx_convolve_avg;
84       sf->predict[0][1][0] = vpx_convolve8_vert;
85       sf->predict[0][1][1] = vpx_convolve8_avg_vert;
86       sf->predict[1][0][0] = vpx_convolve8_horiz;
87       sf->predict[1][0][1] = vpx_convolve8_avg_horiz;
88     } else {
89       // No scaling in x direction. Must always scale in the y direction.
90       sf->predict[0][0][0] = vpx_scaled_vert;
91       sf->predict[0][0][1] = vpx_scaled_avg_vert;
92       sf->predict[0][1][0] = vpx_scaled_vert;
93       sf->predict[0][1][1] = vpx_scaled_avg_vert;
94       sf->predict[1][0][0] = vpx_scaled_2d;
95       sf->predict[1][0][1] = vpx_scaled_avg_2d;
96     }
97   } else {
98     if (sf->y_step_q4 == 16) {
99       // No scaling in the y direction. Must always scale in the x direction.
100       sf->predict[0][0][0] = vpx_scaled_horiz;
101       sf->predict[0][0][1] = vpx_scaled_avg_horiz;
102       sf->predict[0][1][0] = vpx_scaled_2d;
103       sf->predict[0][1][1] = vpx_scaled_avg_2d;
104       sf->predict[1][0][0] = vpx_scaled_horiz;
105       sf->predict[1][0][1] = vpx_scaled_avg_horiz;
106     } else {
107       // Must always scale in both directions.
108       sf->predict[0][0][0] = vpx_scaled_2d;
109       sf->predict[0][0][1] = vpx_scaled_avg_2d;
110       sf->predict[0][1][0] = vpx_scaled_2d;
111       sf->predict[0][1][1] = vpx_scaled_avg_2d;
112       sf->predict[1][0][0] = vpx_scaled_2d;
113       sf->predict[1][0][1] = vpx_scaled_avg_2d;
114     }
115   }
116 
117   // 2D subpel motion always gets filtered in both directions
118 
119   if ((sf->x_step_q4 != 16) || (sf->y_step_q4 != 16)) {
120     sf->predict[1][1][0] = vpx_scaled_2d;
121     sf->predict[1][1][1] = vpx_scaled_avg_2d;
122   } else {
123     sf->predict[1][1][0] = vpx_convolve8;
124     sf->predict[1][1][1] = vpx_convolve8_avg;
125   }
126 
127 #if CONFIG_VP9_HIGHBITDEPTH
128   if (use_highbd) {
129     if (sf->x_step_q4 == 16) {
130       if (sf->y_step_q4 == 16) {
131         // No scaling in either direction.
132         sf->highbd_predict[0][0][0] = vpx_highbd_convolve_copy;
133         sf->highbd_predict[0][0][1] = vpx_highbd_convolve_avg;
134         sf->highbd_predict[0][1][0] = vpx_highbd_convolve8_vert;
135         sf->highbd_predict[0][1][1] = vpx_highbd_convolve8_avg_vert;
136         sf->highbd_predict[1][0][0] = vpx_highbd_convolve8_horiz;
137         sf->highbd_predict[1][0][1] = vpx_highbd_convolve8_avg_horiz;
138       } else {
139         // No scaling in x direction. Must always scale in the y direction.
140         sf->highbd_predict[0][0][0] = vpx_highbd_convolve8_vert;
141         sf->highbd_predict[0][0][1] = vpx_highbd_convolve8_avg_vert;
142         sf->highbd_predict[0][1][0] = vpx_highbd_convolve8_vert;
143         sf->highbd_predict[0][1][1] = vpx_highbd_convolve8_avg_vert;
144         sf->highbd_predict[1][0][0] = vpx_highbd_convolve8;
145         sf->highbd_predict[1][0][1] = vpx_highbd_convolve8_avg;
146       }
147     } else {
148       if (sf->y_step_q4 == 16) {
149         // No scaling in the y direction. Must always scale in the x direction.
150         sf->highbd_predict[0][0][0] = vpx_highbd_convolve8_horiz;
151         sf->highbd_predict[0][0][1] = vpx_highbd_convolve8_avg_horiz;
152         sf->highbd_predict[0][1][0] = vpx_highbd_convolve8;
153         sf->highbd_predict[0][1][1] = vpx_highbd_convolve8_avg;
154         sf->highbd_predict[1][0][0] = vpx_highbd_convolve8_horiz;
155         sf->highbd_predict[1][0][1] = vpx_highbd_convolve8_avg_horiz;
156       } else {
157         // Must always scale in both directions.
158         sf->highbd_predict[0][0][0] = vpx_highbd_convolve8;
159         sf->highbd_predict[0][0][1] = vpx_highbd_convolve8_avg;
160         sf->highbd_predict[0][1][0] = vpx_highbd_convolve8;
161         sf->highbd_predict[0][1][1] = vpx_highbd_convolve8_avg;
162         sf->highbd_predict[1][0][0] = vpx_highbd_convolve8;
163         sf->highbd_predict[1][0][1] = vpx_highbd_convolve8_avg;
164       }
165     }
166     // 2D subpel motion always gets filtered in both directions.
167     sf->highbd_predict[1][1][0] = vpx_highbd_convolve8;
168     sf->highbd_predict[1][1][1] = vpx_highbd_convolve8_avg;
169   }
170 #endif
171 }
172