0,0 → 1,219 |
/* |
* various filters for ACELP-based codecs |
* |
* Copyright (c) 2008 Vladimir Voroshilov |
* |
* This file is part of FFmpeg. |
* |
* FFmpeg is free software; you can redistribute it and/or |
* modify it under the terms of the GNU Lesser General Public |
* License as published by the Free Software Foundation; either |
* version 2.1 of the License, or (at your option) any later version. |
* |
* FFmpeg is distributed in the hope that it will be useful, |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
* Lesser General Public License for more details. |
* |
* You should have received a copy of the GNU Lesser General Public |
* License along with FFmpeg; if not, write to the Free Software |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
*/ |
|
#include <inttypes.h> |
|
#include "avcodec.h" |
#include "celp_filters.h" |
#include "libavutil/avassert.h" |
#include "libavutil/common.h" |
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void ff_celp_convolve_circ(int16_t* fc_out, const int16_t* fc_in, |
const int16_t* filter, int len) |
{ |
int i, k; |
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memset(fc_out, 0, len * sizeof(int16_t)); |
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/* Since there are few pulses over an entire subframe (i.e. almost |
all fc_in[i] are zero) it is faster to loop over fc_in first. */ |
for (i = 0; i < len; i++) { |
if (fc_in[i]) { |
for (k = 0; k < i; k++) |
fc_out[k] += (fc_in[i] * filter[len + k - i]) >> 15; |
|
for (k = i; k < len; k++) |
fc_out[k] += (fc_in[i] * filter[ k - i]) >> 15; |
} |
} |
} |
|
void ff_celp_circ_addf(float *out, const float *in, |
const float *lagged, int lag, float fac, int n) |
{ |
int k; |
for (k = 0; k < lag; k++) |
out[k] = in[k] + fac * lagged[n + k - lag]; |
for (; k < n; k++) |
out[k] = in[k] + fac * lagged[ k - lag]; |
} |
|
int ff_celp_lp_synthesis_filter(int16_t *out, const int16_t *filter_coeffs, |
const int16_t *in, int buffer_length, |
int filter_length, int stop_on_overflow, |
int shift, int rounder) |
{ |
int i,n; |
|
for (n = 0; n < buffer_length; n++) { |
int sum = -rounder, sum1; |
for (i = 1; i <= filter_length; i++) |
sum += filter_coeffs[i-1] * out[n-i]; |
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sum1 = ((-sum >> 12) + in[n]) >> shift; |
sum = av_clip_int16(sum1); |
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if (stop_on_overflow && sum != sum1) |
return 1; |
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out[n] = sum; |
} |
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return 0; |
} |
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void ff_celp_lp_synthesis_filterf(float *out, const float *filter_coeffs, |
const float* in, int buffer_length, |
int filter_length) |
{ |
int i,n; |
|
#if 0 // Unoptimized code path for improved readability |
for (n = 0; n < buffer_length; n++) { |
out[n] = in[n]; |
for (i = 1; i <= filter_length; i++) |
out[n] -= filter_coeffs[i-1] * out[n-i]; |
} |
#else |
float out0, out1, out2, out3; |
float old_out0, old_out1, old_out2, old_out3; |
float a,b,c; |
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a = filter_coeffs[0]; |
b = filter_coeffs[1]; |
c = filter_coeffs[2]; |
b -= filter_coeffs[0] * filter_coeffs[0]; |
c -= filter_coeffs[1] * filter_coeffs[0]; |
c -= filter_coeffs[0] * b; |
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av_assert2((filter_length&1)==0 && filter_length>=4); |
|
old_out0 = out[-4]; |
old_out1 = out[-3]; |
old_out2 = out[-2]; |
old_out3 = out[-1]; |
for (n = 0; n <= buffer_length - 4; n+=4) { |
float tmp0,tmp1,tmp2; |
float val; |
|
out0 = in[0]; |
out1 = in[1]; |
out2 = in[2]; |
out3 = in[3]; |
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out0 -= filter_coeffs[2] * old_out1; |
out1 -= filter_coeffs[2] * old_out2; |
out2 -= filter_coeffs[2] * old_out3; |
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out0 -= filter_coeffs[1] * old_out2; |
out1 -= filter_coeffs[1] * old_out3; |
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out0 -= filter_coeffs[0] * old_out3; |
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val = filter_coeffs[3]; |
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out0 -= val * old_out0; |
out1 -= val * old_out1; |
out2 -= val * old_out2; |
out3 -= val * old_out3; |
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for (i = 5; i < filter_length; i += 2) { |
old_out3 = out[-i]; |
val = filter_coeffs[i-1]; |
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out0 -= val * old_out3; |
out1 -= val * old_out0; |
out2 -= val * old_out1; |
out3 -= val * old_out2; |
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old_out2 = out[-i-1]; |
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val = filter_coeffs[i]; |
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out0 -= val * old_out2; |
out1 -= val * old_out3; |
out2 -= val * old_out0; |
out3 -= val * old_out1; |
|
FFSWAP(float, old_out0, old_out2); |
old_out1 = old_out3; |
} |
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tmp0 = out0; |
tmp1 = out1; |
tmp2 = out2; |
|
out3 -= a * tmp2; |
out2 -= a * tmp1; |
out1 -= a * tmp0; |
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out3 -= b * tmp1; |
out2 -= b * tmp0; |
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out3 -= c * tmp0; |
|
|
out[0] = out0; |
out[1] = out1; |
out[2] = out2; |
out[3] = out3; |
|
old_out0 = out0; |
old_out1 = out1; |
old_out2 = out2; |
old_out3 = out3; |
|
out += 4; |
in += 4; |
} |
|
out -= n; |
in -= n; |
for (; n < buffer_length; n++) { |
out[n] = in[n]; |
for (i = 1; i <= filter_length; i++) |
out[n] -= filter_coeffs[i-1] * out[n-i]; |
} |
#endif |
} |
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void ff_celp_lp_zero_synthesis_filterf(float *out, const float *filter_coeffs, |
const float *in, int buffer_length, |
int filter_length) |
{ |
int i,n; |
|
for (n = 0; n < buffer_length; n++) { |
out[n] = in[n]; |
for (i = 1; i <= filter_length; i++) |
out[n] += filter_coeffs[i-1] * in[n-i]; |
} |
} |
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void ff_celp_filter_init(CELPFContext *c) |
{ |
c->celp_lp_synthesis_filterf = ff_celp_lp_synthesis_filterf; |
c->celp_lp_zero_synthesis_filterf = ff_celp_lp_zero_synthesis_filterf; |
|
if(HAVE_MIPSFPU) |
ff_celp_filter_init_mips(c); |
} |