1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
/*
* Copyright (c) 2018, Alliance for Open Media. All rights reserved
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
#include <stdlib.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <smmintrin.h>
#include "config/av1_rtcd.h"
#include "aom_ports/mem.h"
#include "av1/encoder/corner_match.h"
DECLARE_ALIGNED(16, static const uint8_t, byte_mask[16]) = {
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 0
};
#if MATCH_SZ != 13
#error "Need to change byte_mask in corner_match_sse4.c if MATCH_SZ != 13"
#endif
/* Compute corr(im1, im2) * MATCH_SZ * stddev(im1), where the
correlation/standard deviation are taken over MATCH_SZ by MATCH_SZ windows
of each image, centered at (x1, y1) and (x2, y2) respectively.
*/
double compute_cross_correlation_sse4_1(unsigned char *im1, int stride1, int x1,
int y1, unsigned char *im2, int stride2,
int x2, int y2) {
int i;
// 2 16-bit partial sums in lanes 0, 4 (== 2 32-bit partial sums in lanes 0,
// 2)
__m128i sum1_vec = _mm_setzero_si128();
__m128i sum2_vec = _mm_setzero_si128();
// 4 32-bit partial sums of squares
__m128i sumsq2_vec = _mm_setzero_si128();
__m128i cross_vec = _mm_setzero_si128();
const __m128i mask = _mm_load_si128((__m128i *)byte_mask);
const __m128i zero = _mm_setzero_si128();
im1 += (y1 - MATCH_SZ_BY2) * stride1 + (x1 - MATCH_SZ_BY2);
im2 += (y2 - MATCH_SZ_BY2) * stride2 + (x2 - MATCH_SZ_BY2);
for (i = 0; i < MATCH_SZ; ++i) {
const __m128i v1 =
_mm_and_si128(_mm_loadu_si128((__m128i *)&im1[i * stride1]), mask);
const __m128i v2 =
_mm_and_si128(_mm_loadu_si128((__m128i *)&im2[i * stride2]), mask);
// Using the 'sad' intrinsic here is a bit faster than adding
// v1_l + v1_r and v2_l + v2_r, plus it avoids the need for a 16->32 bit
// conversion step later, for a net speedup of ~10%
sum1_vec = _mm_add_epi16(sum1_vec, _mm_sad_epu8(v1, zero));
sum2_vec = _mm_add_epi16(sum2_vec, _mm_sad_epu8(v2, zero));
const __m128i v1_l = _mm_cvtepu8_epi16(v1);
const __m128i v1_r = _mm_cvtepu8_epi16(_mm_srli_si128(v1, 8));
const __m128i v2_l = _mm_cvtepu8_epi16(v2);
const __m128i v2_r = _mm_cvtepu8_epi16(_mm_srli_si128(v2, 8));
sumsq2_vec = _mm_add_epi32(
sumsq2_vec,
_mm_add_epi32(_mm_madd_epi16(v2_l, v2_l), _mm_madd_epi16(v2_r, v2_r)));
cross_vec = _mm_add_epi32(
cross_vec,
_mm_add_epi32(_mm_madd_epi16(v1_l, v2_l), _mm_madd_epi16(v1_r, v2_r)));
}
// Now we can treat the four registers (sum1_vec, sum2_vec, sumsq2_vec,
// cross_vec)
// as holding 4 32-bit elements each, which we want to sum horizontally.
// We do this by transposing and then summing vertically.
__m128i tmp_0 = _mm_unpacklo_epi32(sum1_vec, sum2_vec);
__m128i tmp_1 = _mm_unpackhi_epi32(sum1_vec, sum2_vec);
__m128i tmp_2 = _mm_unpacklo_epi32(sumsq2_vec, cross_vec);
__m128i tmp_3 = _mm_unpackhi_epi32(sumsq2_vec, cross_vec);
__m128i tmp_4 = _mm_unpacklo_epi64(tmp_0, tmp_2);
__m128i tmp_5 = _mm_unpackhi_epi64(tmp_0, tmp_2);
__m128i tmp_6 = _mm_unpacklo_epi64(tmp_1, tmp_3);
__m128i tmp_7 = _mm_unpackhi_epi64(tmp_1, tmp_3);
__m128i res =
_mm_add_epi32(_mm_add_epi32(tmp_4, tmp_5), _mm_add_epi32(tmp_6, tmp_7));
int sum1 = _mm_extract_epi32(res, 0);
int sum2 = _mm_extract_epi32(res, 1);
int sumsq2 = _mm_extract_epi32(res, 2);
int cross = _mm_extract_epi32(res, 3);
int var2 = sumsq2 * MATCH_SZ_SQ - sum2 * sum2;
int cov = cross * MATCH_SZ_SQ - sum1 * sum2;
return cov / sqrt((double)var2);
}
|
