1dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org/*
2dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
3dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *
4dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *  Use of this source code is governed by a BSD-style license
5dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *  that can be found in the LICENSE file in the root of the source
6dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *  tree. An additional intellectual property rights grant can be found
7dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *  in the file PATENTS.  All contributing project authors may
8dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org *  be found in the AUTHORS file in the root of the source tree.
9dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org */
10dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
11dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include <assert.h>
12dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include <limits.h>
13dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include <math.h>
14dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include <stdio.h>
15dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include <stdlib.h>
16dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include <string.h>
17411971f94253c85e1866c281860d6344f6aa0c78fgalligan@chromium.org
18dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include "vp9/common/vp9_common.h"
19dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#include "vp9/encoder/vp9_resize.h"
20dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
21dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#define FILTER_BITS               7
22dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
23dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#define INTERP_TAPS               8
24dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#define SUBPEL_BITS               5
25dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#define SUBPEL_MASK               ((1 << SUBPEL_BITS) - 1)
26dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org#define INTERP_PRECISION_BITS     32
27dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
28dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgtypedef int16_t interp_kernel[INTERP_TAPS];
29dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
30dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org// Filters for interpolation (0.5-band) - note this also filters integer pels.
31dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgconst interp_kernel vp9_filteredinterp_filters500[(1 << SUBPEL_BITS)] = {
32dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-3,  0, 35, 64, 35,  0, -3, 0},
33dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-3, -1, 34, 64, 36,  1, -3, 0},
34dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-3, -1, 32, 64, 38,  1, -3, 0},
35dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -2, 31, 63, 39,  2, -3, 0},
36dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -2, 29, 63, 41,  2, -3, 0},
37dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -2, 28, 63, 42,  3, -4, 0},
38dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -3, 27, 63, 43,  4, -4, 0},
39dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -3, 25, 62, 45,  5, -4, 0},
40dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -3, 24, 62, 46,  5, -4, 0},
41dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -3, 23, 61, 47,  6, -4, 0},
42dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-2, -3, 21, 60, 49,  7, -4, 0},
43dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 20, 60, 50,  8, -4, -1},
44dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 19, 59, 51,  9, -4, -1},
45dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 17, 58, 52, 10, -4, 0},
46dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 16, 57, 53, 12, -4, -1},
47dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 15, 56, 54, 13, -4, -1},
48dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 14, 55, 55, 14, -4, -1},
49dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 13, 54, 56, 15, -4, -1},
50dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4, 12, 53, 57, 16, -4, -1},
51dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4, 10, 52, 58, 17, -4, -1},
52dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4,  9, 51, 59, 19, -4, -1},
53dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -4,  8, 50, 60, 20, -4, -1},
54dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4,  7, 49, 60, 21, -3, -2},
55dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4,  6, 47, 61, 23, -3, -2},
56dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4,  5, 46, 62, 24, -3, -2},
57dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4,  5, 45, 62, 25, -3, -2},
58dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4,  4, 43, 63, 27, -3, -2},
59dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -4,  3, 42, 63, 28, -2, -2},
60dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -3,  2, 41, 63, 29, -2, -2},
61dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -3,  2, 39, 63, 31, -2, -2},
62dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -3,  1, 38, 64, 32, -1, -3},
63dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -3,  1, 36, 64, 34, -1, -3}
64dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org};
65dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
66dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org// Filters for interpolation (0.625-band) - note this also filters integer pels.
67dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgconst interp_kernel vp9_filteredinterp_filters625[(1 << SUBPEL_BITS)] = {
68dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -8, 33, 80, 33, -8, -1, 0},
69dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -8, 30, 80, 35, -8, -1, 1},
70dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1, -8, 28, 80, 37, -7, -2, 1},
71dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 26, 79, 39, -7, -2, 1},
72dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 24, 79, 41, -7, -2, 1},
73dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 22, 78, 43, -6, -2, 1},
74dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 20, 78, 45, -5, -3, 1},
75dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 18, 77, 48, -5, -3, 1},
76dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 16, 76, 50, -4, -3, 1},
77dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -8, 15, 75, 52, -3, -4, 1},
78dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -7, 13, 74, 54, -3, -4, 1},
79dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -7, 11, 73, 56, -2, -4, 1},
80dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0, -7, 10, 71, 58, -1, -4, 1},
81dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -7,  8, 70, 60,  0, -5, 1},
82dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -6,  6, 68, 62,  1, -5, 1},
83dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -6,  5, 67, 63,  2, -5, 1},
84dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -6,  4, 65, 65,  4, -6, 1},
85dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -5,  2, 63, 67,  5, -6, 1},
86dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -5,  1, 62, 68,  6, -6, 1},
87dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -5,  0, 60, 70,  8, -7, 1},
88dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -4, -1, 58, 71, 10, -7, 0},
89dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -4, -2, 56, 73, 11, -7, 0},
90dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -4, -3, 54, 74, 13, -7, 0},
91dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -4, -3, 52, 75, 15, -8, 0},
92dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -3, -4, 50, 76, 16, -8, 0},
93dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -3, -5, 48, 77, 18, -8, 0},
94dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -3, -5, 45, 78, 20, -8, 0},
95dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -2, -6, 43, 78, 22, -8, 0},
96dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -2, -7, 41, 79, 24, -8, 0},
97dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -2, -7, 39, 79, 26, -8, 0},
98dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -2, -7, 37, 80, 28, -8, -1},
99dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -1, -8, 35, 80, 30, -8, -1},
100dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org};
101dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
102dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org// Filters for interpolation (0.75-band) - note this also filters integer pels.
103dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgconst interp_kernel vp9_filteredinterp_filters750[(1 << SUBPEL_BITS)] = {
104dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2, -11,  25,  96,  25, -11,   2, 0},
105dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2, -11,  22,  96,  28, -11,   2, 0},
106dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2, -10,  19,  95,  31, -11,   2, 0},
107dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2, -10,  17,  95,  34, -12,   2, 0},
108dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -9,  14,  94,  37, -12,   2, 0},
109dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -8,  12,  93,  40, -12,   1, 0},
110dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -8,   9,  92,  43, -12,   1, 1},
111dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -7,   7,  91,  46, -12,   1, 0},
112dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -7,   5,  90,  49, -12,   1, 0},
113dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -6,   3,  88,  52, -12,   0, 1},
114dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -5,   1,  86,  55, -12,   0, 1},
115dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -5,  -1,  84,  58, -11,   0, 1},
116dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -4,  -2,  82,  61, -11,  -1, 1},
117dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -4,  -4,  80,  64, -10,  -1, 1},
118dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -3, -5, 77, 67, -9, -1, 1},
119dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -3, -6, 75, 70, -8, -2, 1},
120dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -2, -7, 72, 72, -7, -2, 1},
121dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -2, -8, 70, 75, -6, -3, 1},
122dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1, -1, -9, 67, 77, -5, -3, 1},
123dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,  -1, -10,  64,  80,  -4,  -4, 2},
124dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,  -1, -11,  61,  82,  -2,  -4, 2},
125dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,   0, -11,  58,  84,  -1,  -5, 2},
126dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,   0, -12,  55,  86,   1,  -5, 2},
127dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,   0, -12,  52,  88,   3,  -6, 2},
128dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1, -12,  49,  90,   5,  -7, 2},
129dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1, -12,  46,  91,   7,  -7, 2},
130dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,   1, -12,  43,  92,   9,  -8, 2},
131dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1, -12,  40,  93,  12,  -8, 2},
132dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2, -12,  37,  94,  14,  -9, 2},
133dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2, -12,  34,  95,  17, -10, 2},
134dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2, -11,  31,  95,  19, -10, 2},
135dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2, -11,  28,  96,  22, -11, 2}
136dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org};
137dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
138dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org// Filters for interpolation (0.875-band) - note this also filters integer pels.
139dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgconst interp_kernel vp9_filteredinterp_filters875[(1 << SUBPEL_BITS)] = {
140dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {3,  -8,  13, 112,  13,  -8,   3, 0},
141dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {3,  -7,  10, 112,  17,  -9,   3, -1},
142dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -6,   7, 111,  21,  -9,   3, -1},
143dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -5,   4, 111,  24, -10,   3, -1},
144dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {2,  -4,   1, 110,  28, -11,   3, -1},
145dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,  -3,  -1, 108,  32, -12,   4, -1},
146dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,  -2,  -3, 106,  36, -13,   4, -1},
147dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,  -1,  -6, 105,  40, -14,   4, -1},
148dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,  -1,  -7, 102,  44, -14,   4, -1},
149dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,   0,  -9, 100,  48, -15,   4, -1},
150dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {1,   1, -11,  97,  53, -16,   4, -1},
151dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1, -12,  95,  57, -16,   4, -1},
152dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2, -13,  91,  61, -16,   4, -1},
153dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2, -14,  88,  65, -16,   4, -1},
154dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   3, -15,  84,  69, -17,   4, 0},
155dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   3, -16,  81,  73, -16,   3, 0},
156dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   3, -16,  77,  77, -16,   3, 0},
157dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   3, -16,  73,  81, -16,   3, 0},
158dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   4, -17,  69,  84, -15,   3, 0},
159dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -16,  65,  88, -14,   2, 0},
160dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -16,  61,  91, -13,   2, 0},
161dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -16,  57,  95, -12,   1, 0},
162dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -16,  53,  97, -11,   1, 1},
163dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -15,  48, 100,  -9,   0, 1},
164dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -14,  44, 102,  -7,  -1, 1},
165dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -14,  40, 105,  -6,  -1, 1},
166dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -13,  36, 106,  -3,  -2, 1},
167dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -12,  32, 108,  -1,  -3, 1},
168dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3, -11,  28, 110,   1,  -4, 2},
169dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3, -10,  24, 111,   4,  -5, 2},
170dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3,  -9,  21, 111,   7,  -6, 2},
171dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3,  -9,  17, 112,  10,  -7, 3}
172dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org};
173dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
174dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org// Filters for interpolation (full-band) - no filtering for integer pixels
175dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgconst interp_kernel vp9_filteredinterp_filters1000[(1 << SUBPEL_BITS)] = {
176dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   0,   0, 128,   0,   0,   0, 0},
177dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1,  -3, 128,   3,  -1,   0, 0},
178dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   2,  -6, 127,   7,  -2,   1, 0},
179dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3,  -9, 126,  12,  -4,   1, 0},
180dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -12, 125,  16,  -5,   1, 0},
181dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -14, 123,  20,  -6,   2, 0},
182dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   5, -15, 120,  25,  -8,   2, 0},
183dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   5, -17, 118,  30,  -9,   3, -1},
184dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -18, 114,  35, -10,   3, -1},
185dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -19, 111,  41, -12,   3, -1},
186dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -20, 107,  46, -13,   4, -1},
187dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -21, 103,  52, -14,   4, -1},
188dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -21,  99,  57, -16,   5, -1},
189dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -21,  94,  63, -17,   5, -1},
190dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -20,  89,  68, -18,   5, -1},
191dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -20,  84,  73, -19,   6, -1},
192dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -20,  79,  79, -20,   6, -1},
193dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   6, -19,  73,  84, -20,   6, -1},
194dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   5, -18,  68,  89, -20,   6, -1},
195dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   5, -17,  63,  94, -21,   6, -1},
196dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   5, -16,  57,  99, -21,   6, -1},
197dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -14,  52, 103, -21,   6, -1},
198dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   4, -13,  46, 107, -20,   6, -1},
199dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3, -12,  41, 111, -19,   6, -1},
200dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3, -10,  35, 114, -18,   6, -1},
201dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {-1,   3,  -9,  30, 118, -17,   5, -1},
202dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2,  -8,  25, 120, -15,   5, -1},
203dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   2,  -6,  20, 123, -14,   4, -1},
204dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1,  -5,  16, 125, -12,   4, -1},
205dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1,  -4,  12, 126,  -9,   3, -1},
206dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   1,  -2,   7, 127,  -6,   2, -1},
207dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  {0,   0,  -1,   3, 128,  -3,   1, 0}
208dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org};
209dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
210dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org// Filters for factor of 2 downsampling.
211dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic const int16_t vp9_down2_symeven_half_filter[] = {56, 12, -3, -1};
212dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic const int16_t vp9_down2_symodd_half_filter[] = {64, 35, 0, -3};
213dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
214dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic const interp_kernel *choose_interp_filter(int inlength, int outlength) {
215dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int outlength16 = outlength * 16;
216dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  if (outlength16 >= inlength * 16)
217dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    return vp9_filteredinterp_filters1000;
218dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  else if (outlength16 >= inlength * 13)
219dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    return vp9_filteredinterp_filters875;
220dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  else if (outlength16 >= inlength * 11)
221dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    return vp9_filteredinterp_filters750;
222dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  else if (outlength16 >= inlength * 9)
223dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    return vp9_filteredinterp_filters625;
224dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  else
225dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    return vp9_filteredinterp_filters500;
226dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
227dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
228dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic void interpolate(const uint8_t *const input, int inlength,
229dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                        uint8_t *output, int outlength) {
230dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  const int64_t delta = (((uint64_t)inlength << 32) + outlength / 2) /
231dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      outlength;
232dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  const int64_t offset = inlength > outlength ?
233dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      (((int64_t)(inlength - outlength) << 31) + outlength / 2) / outlength :
234dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      -(((int64_t)(outlength - inlength) << 31) + outlength / 2) / outlength;
235dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *optr = output;
236dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int x, x1, x2, sum, k, int_pel, sub_pel;
237dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int64_t y;
238dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
239dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  const interp_kernel *interp_filters =
240dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      choose_interp_filter(inlength, outlength);
241dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
242dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  x = 0;
243dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  y = offset;
244dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  while ((y >> INTERP_PRECISION_BITS) < (INTERP_TAPS / 2 - 1)) {
245dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    x++;
246dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    y += delta;
247dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
248dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  x1 = x;
249dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  x = outlength - 1;
250dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  y = delta * x + offset;
251dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  while ((y >> INTERP_PRECISION_BITS) +
252dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org         (int64_t)(INTERP_TAPS / 2) >= inlength) {
253dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    x--;
254dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    y -= delta;
255dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
256dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  x2 = x;
257dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  if (x1 > x2) {
258dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (x = 0, y = offset; x < outlength; ++x, y += delta) {
259dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      const int16_t *filter;
260dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int_pel = y >> INTERP_PRECISION_BITS;
261dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
262dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      filter = interp_filters[sub_pel];
263dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum = 0;
264dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (k = 0; k < INTERP_TAPS; ++k) {
265dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        const int pk = int_pel - INTERP_TAPS / 2 + 1 + k;
266dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += filter[k] * input[(pk < 0 ? 0 :
267dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                                  (pk >= inlength ? inlength - 1 : pk))];
268dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
269dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
270dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
271dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  } else {
272dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Initial part.
273dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (x = 0, y = offset; x < x1; ++x, y += delta) {
274dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      const int16_t *filter;
275dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int_pel = y >> INTERP_PRECISION_BITS;
276dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
277dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      filter = interp_filters[sub_pel];
278dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum = 0;
279dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (k = 0; k < INTERP_TAPS; ++k)
280dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k < 0 ?
281dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                                  0 :
282dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                                  int_pel - INTERP_TAPS / 2 + 1 + k)];
283dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
284dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
285dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Middle part.
286dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (; x <= x2; ++x, y += delta) {
287dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      const int16_t *filter;
288dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int_pel = y >> INTERP_PRECISION_BITS;
289dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
290dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      filter = interp_filters[sub_pel];
291dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum = 0;
292dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (k = 0; k < INTERP_TAPS; ++k)
293dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += filter[k] * input[int_pel - INTERP_TAPS / 2 + 1 + k];
294dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
295dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
296dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // End part.
297dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (; x < outlength; ++x, y += delta) {
298dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      const int16_t *filter;
299dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int_pel = y >> INTERP_PRECISION_BITS;
300dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sub_pel = (y >> (INTERP_PRECISION_BITS - SUBPEL_BITS)) & SUBPEL_MASK;
301dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      filter = interp_filters[sub_pel];
302dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum = 0;
303dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (k = 0; k < INTERP_TAPS; ++k)
304dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += filter[k] * input[(int_pel - INTERP_TAPS / 2 + 1 + k >=
305dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                                  inlength ?  inlength - 1 :
306dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                                  int_pel - INTERP_TAPS / 2 + 1 + k)];
307dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(ROUND_POWER_OF_TWO(sum, FILTER_BITS));
308dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
309dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
310dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
311dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
312dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic void down2_symeven(const uint8_t *const input, int length,
313dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                          uint8_t *output) {
314dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  // Actual filter len = 2 * filter_len_half.
315dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  static const int16_t *filter = vp9_down2_symeven_half_filter;
316dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  const int filter_len_half = sizeof(vp9_down2_symeven_half_filter) / 2;
317dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int i, j;
318dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *optr = output;
319dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int l1 = filter_len_half;
320dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int l2 = (length - filter_len_half);
321dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  l1 += (l1 & 1);
322dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  l2 += (l2 & 1);
323dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  if (l1 > l2) {
324dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Short input length.
325dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (i = 0; i < length; i += 2) {
326dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1));
327dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 0; j < filter_len_half; ++j) {
328dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[(i - j < 0 ? 0 : i - j)] +
329dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                input[(i + 1 + j >= length ? length - 1 : i + 1 + j)]) *
330dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org            filter[j];
331dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
332dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
333dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
334dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
335dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  } else {
336dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Initial part.
337dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (i = 0; i < l1; i += 2) {
338dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1));
339dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 0; j < filter_len_half; ++j) {
340dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[(i - j < 0 ? 0 : i - j)] + input[i + 1 + j]) * filter[j];
341dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
342dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
343dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
344dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
345dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Middle part.
346dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (; i < l2; i += 2) {
347dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1));
348dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 0; j < filter_len_half; ++j) {
349dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[i - j] + input[i + 1 + j]) * filter[j];
350dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
351dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
352dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
353dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
354dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // End part.
355dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (; i < length; i += 2) {
356dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1));
357dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 0; j < filter_len_half; ++j) {
358dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[i - j] +
359dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                input[(i + 1 + j >= length ? length - 1 : i + 1 + j)]) *
360dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org            filter[j];
361dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
362dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
363dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
364dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
365dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
366dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
367dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
368dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic void down2_symodd(const uint8_t *const input, int length,
369dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *output) {
370dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  // Actual filter len = 2 * filter_len_half - 1.
371dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  static const int16_t *filter = vp9_down2_symodd_half_filter;
372dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  const int filter_len_half = sizeof(vp9_down2_symodd_half_filter) / 2;
373dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int i, j;
374dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *optr = output;
375dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int l1 = filter_len_half - 1;
376dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int l2 = (length - filter_len_half + 1);
377dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  l1 += (l1 & 1);
378dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  l2 += (l2 & 1);
379dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  if (l1 > l2) {
380dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Short input length.
381dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (i = 0; i < length; i += 2) {
382dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
383dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 1; j < filter_len_half; ++j) {
384dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[(i - j < 0 ? 0 : i - j)] +
385dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                input[(i + j >= length ? length - 1 : i + j)]) *
386dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org            filter[j];
387dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
388dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
389dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
390dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
391dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  } else {
392dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Initial part.
393dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (i = 0; i < l1; i += 2) {
394dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
395dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 1; j < filter_len_half; ++j) {
396dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[(i - j < 0 ? 0 : i - j)] + input[i + j]) * filter[j];
397dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
398dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
399dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
400dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
401dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // Middle part.
402dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (; i < l2; i += 2) {
403dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
404dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 1; j < filter_len_half; ++j) {
405dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[i - j] + input[i + j]) * filter[j];
406dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
407dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
408dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
409dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
410dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    // End part.
411dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (; i < length; i += 2) {
412dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      int sum = (1 << (FILTER_BITS - 1)) + input[i] * filter[0];
413dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      for (j = 1; j < filter_len_half; ++j) {
414dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        sum += (input[i - j] + input[(i + j >= length ? length - 1 : i + j)]) *
415dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org            filter[j];
416dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      }
417dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      sum >>= FILTER_BITS;
418dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      *optr++ = clip_pixel(sum);
419dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
420dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
421dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
422dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
423dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic int get_down2_length(int length, int steps) {
424dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int s;
425dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  for (s = 0; s < steps; ++s)
426dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    length = (length + 1) >> 1;
427dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  return length;
428dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
429dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
430dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgint get_down2_steps(int in_length, int out_length) {
431dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int steps = 0;
432dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int proj_in_length;
433dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  while ((proj_in_length = get_down2_length(in_length, 1)) >= out_length) {
434dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    ++steps;
435dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    in_length = proj_in_length;
436dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
437dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  return steps;
438dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
439dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
440dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic void resize_multistep(const uint8_t *const input,
441dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                             int length,
442dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                             uint8_t *output,
443dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                             int olength,
444dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                             uint8_t *buf) {
445dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int steps;
446dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  if (length == olength) {
447dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    memcpy(output, input, sizeof(uint8_t) * length);
448dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    return;
449dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
450dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  steps = get_down2_steps(length, olength);
451dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
452dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  if (steps > 0) {
453dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    int s;
454dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    uint8_t *out = NULL;
455dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    uint8_t *tmpbuf = NULL;
456dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    uint8_t *otmp, *otmp2;
457dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    int filteredlength = length;
458dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    if (!tmpbuf) {
459dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      tmpbuf = (uint8_t *)malloc(sizeof(uint8_t) * length);
460dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      otmp = tmpbuf;
461dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    } else {
462dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      otmp = buf;
463dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
464dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    otmp2 = otmp + get_down2_length(length, 1);
465dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    for (s = 0; s < steps; ++s) {
466dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      const int proj_filteredlength = get_down2_length(filteredlength, 1);
467dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      const uint8_t *const in = (s == 0 ? input : out);
468dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      if (s == steps - 1 && proj_filteredlength == olength)
469dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        out = output;
470dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      else
471dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        out = (s & 1 ? otmp2 : otmp);
472dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      if (filteredlength & 1)
473dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        down2_symodd(in, filteredlength, out);
474dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      else
475dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org        down2_symeven(in, filteredlength, out);
476dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      filteredlength = proj_filteredlength;
477dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
478dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    if (filteredlength != olength) {
479dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      interpolate(out, filteredlength, output, olength);
480dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    }
481dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    if (tmpbuf)
482dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org      free(tmpbuf);
483dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  } else {
484dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    interpolate(input, length, output, olength);
485dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
486dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
487dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
488dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic void fill_col_to_arr(uint8_t *img, int stride, int len, uint8_t *arr) {
489dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int i;
490dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *iptr = img;
491dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *aptr = arr;
492dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  for (i = 0; i < len; ++i, iptr += stride) {
493dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    *aptr++ = *iptr;
494dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
495dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
496dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
497dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgstatic void fill_arr_to_col(uint8_t *img, int stride, int len, uint8_t *arr) {
498dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int i;
499dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *iptr = img;
500dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *aptr = arr;
501dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  for (i = 0; i < len; ++i, iptr += stride) {
502dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    *iptr = *aptr++;
503dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
504dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
505dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
506dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgvoid vp9_resize_plane(const uint8_t *const input,
507dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      int height,
508dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      int width,
509dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      int in_stride,
510dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      uint8_t *output,
511dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      int height2,
512dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      int width2,
513dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                      int out_stride) {
514dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  int i;
515dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *intbuf = (uint8_t *)malloc(sizeof(uint8_t) * width2 * height);
516dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *tmpbuf = (uint8_t *)malloc(sizeof(uint8_t) *
517dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                                      (width < height ? height : width));
518dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  uint8_t *arrbuf = (uint8_t *)malloc(sizeof(uint8_t) * (height + height2));
519dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  for (i = 0; i < height; ++i)
520dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    resize_multistep(input + in_stride * i, width,
521dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                        intbuf + width2 * i, width2, tmpbuf);
522dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  for (i = 0; i < width2; ++i) {
523dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    fill_col_to_arr(intbuf + i, width2, height, arrbuf);
524dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    resize_multistep(arrbuf, height, arrbuf + height, height2, tmpbuf);
525dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org    fill_arr_to_col(output + i, out_stride, height2, arrbuf + height);
526dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  }
527dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  free(intbuf);
528dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  free(tmpbuf);
529dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  free(arrbuf);
530dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
531dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
532dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgvoid vp9_resize_frame420(const uint8_t *const y,
533dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int y_stride,
534dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         const uint8_t *const u, const uint8_t *const v,
535dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int uv_stride,
536dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int height, int width,
537dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *oy, int oy_stride,
538dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *ou, uint8_t *ov, int ouv_stride,
539dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int oheight, int owidth) {
540dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(y, height, width, y_stride,
541dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   oy, oheight, owidth, oy_stride);
542dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(u, height / 2, width / 2, uv_stride,
543dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   ou, oheight / 2, owidth / 2, ouv_stride);
544dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(v, height / 2, width / 2, uv_stride,
545dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   ov, oheight / 2, owidth / 2, ouv_stride);
546dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
547dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
548dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgvoid vp9_resize_frame422(const uint8_t *const y, int y_stride,
549dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         const uint8_t *const u, const uint8_t *const v,
550dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int uv_stride,
551dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int height, int width,
552dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *oy, int oy_stride,
553dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *ou, uint8_t *ov, int ouv_stride,
554dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int oheight, int owidth) {
555dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(y, height, width, y_stride,
556dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   oy, oheight, owidth, oy_stride);
557dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(u, height, width / 2, uv_stride,
558dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   ou, oheight, owidth / 2, ouv_stride);
559dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(v, height, width / 2, uv_stride,
560dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   ov, oheight, owidth / 2, ouv_stride);
561dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
562dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org
563dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.orgvoid vp9_resize_frame444(const uint8_t *const y, int y_stride,
564dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         const uint8_t *const u, const uint8_t *const v,
565dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int uv_stride,
566dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int height, int width,
567dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *oy, int oy_stride,
568dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         uint8_t *ou, uint8_t *ov, int ouv_stride,
569dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                         int oheight, int owidth) {
570dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(y, height, width, y_stride,
571dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   oy, oheight, owidth, oy_stride);
572dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(u, height, width, uv_stride,
573dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   ou, oheight, owidth, ouv_stride);
574dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org  vp9_resize_plane(v, height, width, uv_stride,
575dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org                   ov, oheight, owidth, ouv_stride);
576dddee1ec7cedf276305b107429f684539b105276johannkoenig@chromium.org}
577