media/libopus/silk/resampler_private_up2_HQ.c

Thu, 15 Jan 2015 15:59:08 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Thu, 15 Jan 2015 15:59:08 +0100
branch
TOR_BUG_9701
changeset 10
ac0c01689b40
permissions
-rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

michael@0 1 /***********************************************************************
michael@0 2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
michael@0 3 Redistribution and use in source and binary forms, with or without
michael@0 4 modification, are permitted provided that the following conditions
michael@0 5 are met:
michael@0 6 - Redistributions of source code must retain the above copyright notice,
michael@0 7 this list of conditions and the following disclaimer.
michael@0 8 - Redistributions in binary form must reproduce the above copyright
michael@0 9 notice, this list of conditions and the following disclaimer in the
michael@0 10 documentation and/or other materials provided with the distribution.
michael@0 11 - Neither the name of Internet Society, IETF or IETF Trust, nor the
michael@0 12 names of specific contributors, may be used to endorse or promote
michael@0 13 products derived from this software without specific prior written
michael@0 14 permission.
michael@0 15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
michael@0 16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
michael@0 17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
michael@0 18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
michael@0 19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
michael@0 20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
michael@0 21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
michael@0 22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
michael@0 23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0 24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
michael@0 25 POSSIBILITY OF SUCH DAMAGE.
michael@0 26 ***********************************************************************/
michael@0 27
michael@0 28 #ifdef HAVE_CONFIG_H
michael@0 29 #include "config.h"
michael@0 30 #endif
michael@0 31
michael@0 32 #include "SigProc_FIX.h"
michael@0 33 #include "resampler_private.h"
michael@0 34
michael@0 35 /* Upsample by a factor 2, high quality */
michael@0 36 /* Uses 2nd order allpass filters for the 2x upsampling, followed by a */
michael@0 37 /* notch filter just above Nyquist. */
michael@0 38 void silk_resampler_private_up2_HQ(
michael@0 39 opus_int32 *S, /* I/O Resampler state [ 6 ] */
michael@0 40 opus_int16 *out, /* O Output signal [ 2 * len ] */
michael@0 41 const opus_int16 *in, /* I Input signal [ len ] */
michael@0 42 opus_int32 len /* I Number of input samples */
michael@0 43 )
michael@0 44 {
michael@0 45 opus_int32 k;
michael@0 46 opus_int32 in32, out32_1, out32_2, Y, X;
michael@0 47
michael@0 48 silk_assert( silk_resampler_up2_hq_0[ 0 ] > 0 );
michael@0 49 silk_assert( silk_resampler_up2_hq_0[ 1 ] > 0 );
michael@0 50 silk_assert( silk_resampler_up2_hq_0[ 2 ] < 0 );
michael@0 51 silk_assert( silk_resampler_up2_hq_1[ 0 ] > 0 );
michael@0 52 silk_assert( silk_resampler_up2_hq_1[ 1 ] > 0 );
michael@0 53 silk_assert( silk_resampler_up2_hq_1[ 2 ] < 0 );
michael@0 54
michael@0 55 /* Internal variables and state are in Q10 format */
michael@0 56 for( k = 0; k < len; k++ ) {
michael@0 57 /* Convert to Q10 */
michael@0 58 in32 = silk_LSHIFT( (opus_int32)in[ k ], 10 );
michael@0 59
michael@0 60 /* First all-pass section for even output sample */
michael@0 61 Y = silk_SUB32( in32, S[ 0 ] );
michael@0 62 X = silk_SMULWB( Y, silk_resampler_up2_hq_0[ 0 ] );
michael@0 63 out32_1 = silk_ADD32( S[ 0 ], X );
michael@0 64 S[ 0 ] = silk_ADD32( in32, X );
michael@0 65
michael@0 66 /* Second all-pass section for even output sample */
michael@0 67 Y = silk_SUB32( out32_1, S[ 1 ] );
michael@0 68 X = silk_SMULWB( Y, silk_resampler_up2_hq_0[ 1 ] );
michael@0 69 out32_2 = silk_ADD32( S[ 1 ], X );
michael@0 70 S[ 1 ] = silk_ADD32( out32_1, X );
michael@0 71
michael@0 72 /* Third all-pass section for even output sample */
michael@0 73 Y = silk_SUB32( out32_2, S[ 2 ] );
michael@0 74 X = silk_SMLAWB( Y, Y, silk_resampler_up2_hq_0[ 2 ] );
michael@0 75 out32_1 = silk_ADD32( S[ 2 ], X );
michael@0 76 S[ 2 ] = silk_ADD32( out32_2, X );
michael@0 77
michael@0 78 /* Apply gain in Q15, convert back to int16 and store to output */
michael@0 79 out[ 2 * k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( out32_1, 10 ) );
michael@0 80
michael@0 81 /* First all-pass section for odd output sample */
michael@0 82 Y = silk_SUB32( in32, S[ 3 ] );
michael@0 83 X = silk_SMULWB( Y, silk_resampler_up2_hq_1[ 0 ] );
michael@0 84 out32_1 = silk_ADD32( S[ 3 ], X );
michael@0 85 S[ 3 ] = silk_ADD32( in32, X );
michael@0 86
michael@0 87 /* Second all-pass section for odd output sample */
michael@0 88 Y = silk_SUB32( out32_1, S[ 4 ] );
michael@0 89 X = silk_SMULWB( Y, silk_resampler_up2_hq_1[ 1 ] );
michael@0 90 out32_2 = silk_ADD32( S[ 4 ], X );
michael@0 91 S[ 4 ] = silk_ADD32( out32_1, X );
michael@0 92
michael@0 93 /* Third all-pass section for odd output sample */
michael@0 94 Y = silk_SUB32( out32_2, S[ 5 ] );
michael@0 95 X = silk_SMLAWB( Y, Y, silk_resampler_up2_hq_1[ 2 ] );
michael@0 96 out32_1 = silk_ADD32( S[ 5 ], X );
michael@0 97 S[ 5 ] = silk_ADD32( out32_2, X );
michael@0 98
michael@0 99 /* Apply gain in Q15, convert back to int16 and store to output */
michael@0 100 out[ 2 * k + 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( out32_1, 10 ) );
michael@0 101 }
michael@0 102 }
michael@0 103
michael@0 104 void silk_resampler_private_up2_HQ_wrapper(
michael@0 105 void *SS, /* I/O Resampler state (unused) */
michael@0 106 opus_int16 *out, /* O Output signal [ 2 * len ] */
michael@0 107 const opus_int16 *in, /* I Input signal [ len ] */
michael@0 108 opus_int32 len /* I Number of input samples */
michael@0 109 )
michael@0 110 {
michael@0 111 silk_resampler_state_struct *S = (silk_resampler_state_struct *)SS;
michael@0 112 silk_resampler_private_up2_HQ( S->sIIR, out, in, len );
michael@0 113 }

mercurial