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109 lines
3.4 KiB
109 lines
3.4 KiB
/* |
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* Copyright (c) 2011 Mans Rullgard |
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* |
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* This file is part of FFmpeg. |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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#include "config.h" |
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#include "libavutil/attributes.h" |
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#include "libavutil/thread.h" |
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#include "mpegaudio.h" |
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#include "mpegaudiodsp.h" |
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#include "dct32.h" |
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static AVOnce mpadsp_table_init = AV_ONCE_INIT; |
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static av_cold void mpadsp_init_tabs(void) |
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{ |
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int i, j; |
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/* compute mdct windows */ |
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for (i = 0; i < 36; i++) { |
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for (j = 0; j < 4; j++) { |
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double d; |
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if (j == 2 && i % 3 != 1) |
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continue; |
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d = sin(M_PI * (i + 0.5) / 36.0); |
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if (j == 1) { |
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if (i >= 30) d = 0; |
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else if (i >= 24) d = sin(M_PI * (i - 18 + 0.5) / 12.0); |
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else if (i >= 18) d = 1; |
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} else if (j == 3) { |
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if (i < 6) d = 0; |
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else if (i < 12) d = sin(M_PI * (i - 6 + 0.5) / 12.0); |
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else if (i < 18) d = 1; |
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} |
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//merge last stage of imdct into the window coefficients |
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d *= 0.5 * IMDCT_SCALAR / cos(M_PI * (2 * i + 19) / 72); |
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if (j == 2) { |
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ff_mdct_win_float[j][i/3] = d / (1 << 5); |
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ff_mdct_win_fixed[j][i/3] = d / (1 << 5) * (1LL << 32) + 0.5; |
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} else { |
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int idx = i < 18 ? i : i + (MDCT_BUF_SIZE/2 - 18); |
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ff_mdct_win_float[j][idx] = d / (1 << 5); |
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ff_mdct_win_fixed[j][idx] = d / (1 << 5) * (1LL << 32) + 0.5; |
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} |
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} |
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} |
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/* NOTE: we do frequency inversion after the MDCT by changing |
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the sign of the right window coefs */ |
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for (j = 0; j < 4; j++) { |
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for (i = 0; i < MDCT_BUF_SIZE; i += 2) { |
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ff_mdct_win_float[j + 4][i ] = ff_mdct_win_float[j][i ]; |
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ff_mdct_win_float[j + 4][i + 1] = -ff_mdct_win_float[j][i + 1]; |
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ff_mdct_win_fixed[j + 4][i ] = ff_mdct_win_fixed[j][i ]; |
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ff_mdct_win_fixed[j + 4][i + 1] = -ff_mdct_win_fixed[j][i + 1]; |
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} |
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} |
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#if ARCH_X86 |
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ff_mpadsp_init_x86_tabs(); |
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#endif |
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} |
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av_cold void ff_mpadsp_init(MPADSPContext *s) |
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{ |
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ff_thread_once(&mpadsp_table_init, &mpadsp_init_tabs); |
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s->apply_window_float = ff_mpadsp_apply_window_float; |
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s->apply_window_fixed = ff_mpadsp_apply_window_fixed; |
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s->dct32_float = ff_dct32_float; |
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s->dct32_fixed = ff_dct32_fixed; |
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s->imdct36_blocks_float = ff_imdct36_blocks_float; |
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s->imdct36_blocks_fixed = ff_imdct36_blocks_fixed; |
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#if ARCH_AARCH64 |
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ff_mpadsp_init_aarch64(s); |
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#elif ARCH_ARM |
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ff_mpadsp_init_arm(s); |
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#elif ARCH_PPC |
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ff_mpadsp_init_ppc(s); |
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#elif ARCH_X86 |
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ff_mpadsp_init_x86(s); |
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#endif |
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#if HAVE_MIPSFPU |
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ff_mpadsp_init_mipsfpu(s); |
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#endif |
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#if HAVE_MIPSDSP |
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ff_mpadsp_init_mipsdsp(s); |
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#endif |
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}
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