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-rw-r--r--thirdparty/opus/silk/LP_variable_cutoff.c135
1 files changed, 0 insertions, 135 deletions
diff --git a/thirdparty/opus/silk/LP_variable_cutoff.c b/thirdparty/opus/silk/LP_variable_cutoff.c
deleted file mode 100644
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--- a/thirdparty/opus/silk/LP_variable_cutoff.c
+++ /dev/null
@@ -1,135 +0,0 @@
-/***********************************************************************
-Copyright (c) 2006-2011, Skype Limited. All rights reserved.
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-- Redistributions of source code must retain the above copyright notice,
-this list of conditions and the following disclaimer.
-- Redistributions in binary form must reproduce the above copyright
-notice, this list of conditions and the following disclaimer in the
-documentation and/or other materials provided with the distribution.
-- Neither the name of Internet Society, IETF or IETF Trust, nor the
-names of specific contributors, may be used to endorse or promote
-products derived from this software without specific prior written
-permission.
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-***********************************************************************/
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-/*
- Elliptic/Cauer filters designed with 0.1 dB passband ripple,
- 80 dB minimum stopband attenuation, and
- [0.95 : 0.15 : 0.35] normalized cut off frequencies.
-*/
-
-#include "main.h"
-
-/* Helper function, interpolates the filter taps */
-static OPUS_INLINE void silk_LP_interpolate_filter_taps(
- opus_int32 B_Q28[ TRANSITION_NB ],
- opus_int32 A_Q28[ TRANSITION_NA ],
- const opus_int ind,
- const opus_int32 fac_Q16
-)
-{
- opus_int nb, na;
-
- if( ind < TRANSITION_INT_NUM - 1 ) {
- if( fac_Q16 > 0 ) {
- if( fac_Q16 < 32768 ) { /* fac_Q16 is in range of a 16-bit int */
- /* Piece-wise linear interpolation of B and A */
- for( nb = 0; nb < TRANSITION_NB; nb++ ) {
- B_Q28[ nb ] = silk_SMLAWB(
- silk_Transition_LP_B_Q28[ ind ][ nb ],
- silk_Transition_LP_B_Q28[ ind + 1 ][ nb ] -
- silk_Transition_LP_B_Q28[ ind ][ nb ],
- fac_Q16 );
- }
- for( na = 0; na < TRANSITION_NA; na++ ) {
- A_Q28[ na ] = silk_SMLAWB(
- silk_Transition_LP_A_Q28[ ind ][ na ],
- silk_Transition_LP_A_Q28[ ind + 1 ][ na ] -
- silk_Transition_LP_A_Q28[ ind ][ na ],
- fac_Q16 );
- }
- } else { /* ( fac_Q16 - ( 1 << 16 ) ) is in range of a 16-bit int */
- silk_assert( fac_Q16 - ( 1 << 16 ) == silk_SAT16( fac_Q16 - ( 1 << 16 ) ) );
- /* Piece-wise linear interpolation of B and A */
- for( nb = 0; nb < TRANSITION_NB; nb++ ) {
- B_Q28[ nb ] = silk_SMLAWB(
- silk_Transition_LP_B_Q28[ ind + 1 ][ nb ],
- silk_Transition_LP_B_Q28[ ind + 1 ][ nb ] -
- silk_Transition_LP_B_Q28[ ind ][ nb ],
- fac_Q16 - ( (opus_int32)1 << 16 ) );
- }
- for( na = 0; na < TRANSITION_NA; na++ ) {
- A_Q28[ na ] = silk_SMLAWB(
- silk_Transition_LP_A_Q28[ ind + 1 ][ na ],
- silk_Transition_LP_A_Q28[ ind + 1 ][ na ] -
- silk_Transition_LP_A_Q28[ ind ][ na ],
- fac_Q16 - ( (opus_int32)1 << 16 ) );
- }
- }
- } else {
- silk_memcpy( B_Q28, silk_Transition_LP_B_Q28[ ind ], TRANSITION_NB * sizeof( opus_int32 ) );
- silk_memcpy( A_Q28, silk_Transition_LP_A_Q28[ ind ], TRANSITION_NA * sizeof( opus_int32 ) );
- }
- } else {
- silk_memcpy( B_Q28, silk_Transition_LP_B_Q28[ TRANSITION_INT_NUM - 1 ], TRANSITION_NB * sizeof( opus_int32 ) );
- silk_memcpy( A_Q28, silk_Transition_LP_A_Q28[ TRANSITION_INT_NUM - 1 ], TRANSITION_NA * sizeof( opus_int32 ) );
- }
-}
-
-/* Low-pass filter with variable cutoff frequency based on */
-/* piece-wise linear interpolation between elliptic filters */
-/* Start by setting psEncC->mode <> 0; */
-/* Deactivate by setting psEncC->mode = 0; */
-void silk_LP_variable_cutoff(
- silk_LP_state *psLP, /* I/O LP filter state */
- opus_int16 *frame, /* I/O Low-pass filtered output signal */
- const opus_int frame_length /* I Frame length */
-)
-{
- opus_int32 B_Q28[ TRANSITION_NB ], A_Q28[ TRANSITION_NA ], fac_Q16 = 0;
- opus_int ind = 0;
-
- silk_assert( psLP->transition_frame_no >= 0 && psLP->transition_frame_no <= TRANSITION_FRAMES );
-
- /* Run filter if needed */
- if( psLP->mode != 0 ) {
- /* Calculate index and interpolation factor for interpolation */
-#if( TRANSITION_INT_STEPS == 64 )
- fac_Q16 = silk_LSHIFT( TRANSITION_FRAMES - psLP->transition_frame_no, 16 - 6 );
-#else
- fac_Q16 = silk_DIV32_16( silk_LSHIFT( TRANSITION_FRAMES - psLP->transition_frame_no, 16 ), TRANSITION_FRAMES );
-#endif
- ind = silk_RSHIFT( fac_Q16, 16 );
- fac_Q16 -= silk_LSHIFT( ind, 16 );
-
- silk_assert( ind >= 0 );
- silk_assert( ind < TRANSITION_INT_NUM );
-
- /* Interpolate filter coefficients */
- silk_LP_interpolate_filter_taps( B_Q28, A_Q28, ind, fac_Q16 );
-
- /* Update transition frame number for next frame */
- psLP->transition_frame_no = silk_LIMIT( psLP->transition_frame_no + psLP->mode, 0, TRANSITION_FRAMES );
-
- /* ARMA low-pass filtering */
- silk_assert( TRANSITION_NB == 3 && TRANSITION_NA == 2 );
- silk_biquad_alt( frame, B_Q28, A_Q28, psLP->In_LP_State, frame, frame_length, 1);
- }
-}