Line | Branch | Exec | Source |
---|---|---|---|
1 | /* | ||
2 | * LPC utility functions | ||
3 | * Copyright (c) 2006 Justin Ruggles <justin.ruggles@gmail.com> | ||
4 | * | ||
5 | * This file is part of FFmpeg. | ||
6 | * | ||
7 | * FFmpeg is free software; you can redistribute it and/or | ||
8 | * modify it under the terms of the GNU Lesser General Public | ||
9 | * License as published by the Free Software Foundation; either | ||
10 | * version 2.1 of the License, or (at your option) any later version. | ||
11 | * | ||
12 | * FFmpeg is distributed in the hope that it will be useful, | ||
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
15 | * Lesser General Public License for more details. | ||
16 | * | ||
17 | * You should have received a copy of the GNU Lesser General Public | ||
18 | * License along with FFmpeg; if not, write to the Free Software | ||
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
20 | */ | ||
21 | |||
22 | #ifndef AVCODEC_LPC_FUNCTIONS_H | ||
23 | #define AVCODEC_LPC_FUNCTIONS_H | ||
24 | |||
25 | #include "libavutil/avassert.h" | ||
26 | |||
27 | #ifndef LPC_USE_FIXED | ||
28 | #define LPC_USE_FIXED 0 | ||
29 | #endif | ||
30 | |||
31 | #if LPC_USE_FIXED | ||
32 | typedef int LPC_TYPE; | ||
33 | typedef unsigned LPC_TYPE_U; | ||
34 | #else | ||
35 | #ifndef LPC_SRA_R | ||
36 | #define LPC_SRA_R(x, y) (x) | ||
37 | #define LPC_MUL26(x, y) ((x) * (y)) | ||
38 | #define LPC_FIXR(x) ((float)(x)) | ||
39 | #endif | ||
40 | |||
41 | #ifdef LPC_USE_DOUBLE | ||
42 | typedef double LPC_TYPE; | ||
43 | typedef double LPC_TYPE_U; | ||
44 | #else | ||
45 | typedef float LPC_TYPE; | ||
46 | typedef float LPC_TYPE_U; | ||
47 | #endif | ||
48 | #endif // USE_FIXED | ||
49 | |||
50 | /** | ||
51 | * Levinson-Durbin recursion. | ||
52 | * Produce LPC coefficients from autocorrelation data. | ||
53 | */ | ||
54 | 38180 | static inline int compute_lpc_coefs(const LPC_TYPE *autoc, int max_order, | |
55 | LPC_TYPE *lpc, int lpc_stride, int fail, | ||
56 | int normalize) | ||
57 | { | ||
58 | 38180 | LPC_TYPE err = 0; | |
59 | 38180 | LPC_TYPE *lpc_last = lpc; | |
60 | |||
61 | av_assert2(normalize || !fail); | ||
62 | |||
63 |
2/2✓ Branch 0 taken 29215 times.
✓ Branch 1 taken 8965 times.
|
38180 | if (normalize) |
64 | 29215 | err = *autoc++; | |
65 | |||
66 |
5/6✓ Branch 0 taken 19592 times.
✓ Branch 1 taken 18588 times.
✓ Branch 2 taken 19588 times.
✓ Branch 3 taken 4 times.
✗ Branch 4 not taken.
✓ Branch 5 taken 19588 times.
|
38180 | if (fail && (autoc[max_order - 1] == 0 || err <= 0)) |
67 | 4 | return -1; | |
68 | |||
69 |
2/2✓ Branch 0 taken 610994 times.
✓ Branch 1 taken 38176 times.
|
649170 | for(int i = 0; i < max_order; i++) { |
70 | 610994 | LPC_TYPE r = LPC_SRA_R(-autoc[i], 5); | |
71 | |||
72 |
2/2✓ Branch 0 taken 551934 times.
✓ Branch 1 taken 59060 times.
|
610994 | if (normalize) { |
73 |
2/2✓ Branch 0 taken 7345215 times.
✓ Branch 1 taken 551934 times.
|
7897149 | for(int j = 0; j < i; j++) |
74 | 7345215 | r -= lpc_last[j] * autoc[i-j-1]; | |
75 | |||
76 |
1/2✓ Branch 0 taken 551934 times.
✗ Branch 1 not taken.
|
551934 | if (err) |
77 | 551934 | r /= err; | |
78 | 551934 | err *= LPC_FIXR(1.0) - (r * r); | |
79 | } | ||
80 | |||
81 | 610994 | lpc[i] = r; | |
82 | |||
83 |
2/2✓ Branch 0 taken 3936605 times.
✓ Branch 1 taken 610994 times.
|
4547599 | for(int j = 0; j < (i + 1) >> 1; j++) { |
84 | 3936605 | LPC_TYPE f = lpc_last[ j]; | |
85 | 3936605 | LPC_TYPE b = lpc_last[i-1-j]; | |
86 | 3936605 | lpc[ j] = f + (LPC_TYPE_U)LPC_MUL26(r, b); | |
87 | 3936605 | lpc[i-1-j] = b + (LPC_TYPE_U)LPC_MUL26(r, f); | |
88 | } | ||
89 | |||
90 |
3/4✓ Branch 0 taken 450524 times.
✓ Branch 1 taken 160470 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 450524 times.
|
610994 | if (fail && err < 0) |
91 | ✗ | return -1; | |
92 | |||
93 | 610994 | lpc_last = lpc; | |
94 | 610994 | lpc += lpc_stride; | |
95 | } | ||
96 | |||
97 | 38176 | return 0; | |
98 | } | ||
99 | |||
100 | #endif /* AVCODEC_LPC_FUNCTIONS_H */ | ||
101 |