diff options
Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/stereo_quant_pred.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/stereo_quant_pred.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/stereo_quant_pred.c b/lib/rbcodec/codecs/libopus/silk/stereo_quant_pred.c new file mode 100644 index 0000000000..d4ced6c3e8 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/stereo_quant_pred.c | |||
@@ -0,0 +1,73 @@ | |||
1 | /*********************************************************************** | ||
2 | Copyright (c) 2006-2011, Skype Limited. All rights reserved. | ||
3 | Redistribution and use in source and binary forms, with or without | ||
4 | modification, are permitted provided that the following conditions | ||
5 | are met: | ||
6 | - Redistributions of source code must retain the above copyright notice, | ||
7 | this list of conditions and the following disclaimer. | ||
8 | - Redistributions in binary form must reproduce the above copyright | ||
9 | notice, this list of conditions and the following disclaimer in the | ||
10 | documentation and/or other materials provided with the distribution. | ||
11 | - Neither the name of Internet Society, IETF or IETF Trust, nor the | ||
12 | names of specific contributors, may be used to endorse or promote | ||
13 | products derived from this software without specific prior written | ||
14 | permission. | ||
15 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | ||
16 | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
17 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
18 | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | ||
19 | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | ||
20 | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | ||
21 | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | ||
22 | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | ||
23 | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
24 | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | ||
25 | POSSIBILITY OF SUCH DAMAGE. | ||
26 | ***********************************************************************/ | ||
27 | |||
28 | #ifdef HAVE_CONFIG_H | ||
29 | #include "config.h" | ||
30 | #endif | ||
31 | |||
32 | #include "main.h" | ||
33 | |||
34 | /* Quantize mid/side predictors */ | ||
35 | void silk_stereo_quant_pred( | ||
36 | opus_int32 pred_Q13[], /* I/O Predictors (out: quantized) */ | ||
37 | opus_int8 ix[ 2 ][ 3 ] /* O Quantization indices */ | ||
38 | ) | ||
39 | { | ||
40 | opus_int i, j, n; | ||
41 | opus_int32 low_Q13, step_Q13, lvl_Q13, err_min_Q13, err_Q13, quant_pred_Q13 = 0; | ||
42 | |||
43 | /* Quantize */ | ||
44 | for( n = 0; n < 2; n++ ) { | ||
45 | /* Brute-force search over quantization levels */ | ||
46 | err_min_Q13 = silk_int32_MAX; | ||
47 | for( i = 0; i < STEREO_QUANT_TAB_SIZE - 1; i++ ) { | ||
48 | low_Q13 = silk_stereo_pred_quant_Q13[ i ]; | ||
49 | step_Q13 = silk_SMULWB( silk_stereo_pred_quant_Q13[ i + 1 ] - low_Q13, | ||
50 | SILK_FIX_CONST( 0.5 / STEREO_QUANT_SUB_STEPS, 16 ) ); | ||
51 | for( j = 0; j < STEREO_QUANT_SUB_STEPS; j++ ) { | ||
52 | lvl_Q13 = silk_SMLABB( low_Q13, step_Q13, 2 * j + 1 ); | ||
53 | err_Q13 = silk_abs( pred_Q13[ n ] - lvl_Q13 ); | ||
54 | if( err_Q13 < err_min_Q13 ) { | ||
55 | err_min_Q13 = err_Q13; | ||
56 | quant_pred_Q13 = lvl_Q13; | ||
57 | ix[ n ][ 0 ] = i; | ||
58 | ix[ n ][ 1 ] = j; | ||
59 | } else { | ||
60 | /* Error increasing, so we're past the optimum */ | ||
61 | goto done; | ||
62 | } | ||
63 | } | ||
64 | } | ||
65 | done: | ||
66 | ix[ n ][ 2 ] = silk_DIV32_16( ix[ n ][ 0 ], 3 ); | ||
67 | ix[ n ][ 0 ] -= ix[ n ][ 2 ] * 3; | ||
68 | pred_Q13[ n ] = quant_pred_Q13; | ||
69 | } | ||
70 | |||
71 | /* Subtract second from first predictor (helps when actually applying these) */ | ||
72 | pred_Q13[ 0 ] -= pred_Q13[ 1 ]; | ||
73 | } | ||