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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 <stdint.h> |
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#include "libavutil/avassert.h" |
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#include "avfilter.h" |
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#include "generate_wave_table.h" |
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void ff_generate_wave_table(enum WaveType wave_type, |
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enum AVSampleFormat sample_fmt, |
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void *table, int table_size, |
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double min, double max, double phase) |
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{ |
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uint32_t i, phase_offset = phase / M_PI / 2 * table_size + 0.5; |
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✓✓ |
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for (i = 0; i < table_size; i++) { |
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uint32_t point = (i + phase_offset) % table_size; |
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double d; |
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✓✗✗ |
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switch (wave_type) { |
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case WAVE_SIN: |
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d = (sin((double)point / table_size * 2 * M_PI) + 1) / 2; |
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break; |
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case WAVE_TRI: |
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d = (double)point * 2 / table_size; |
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switch (4 * point / table_size) { |
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case 0: d = d + 0.5; break; |
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case 1: |
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case 2: d = 1.5 - d; break; |
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case 3: d = d - 1.5; break; |
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} |
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break; |
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default: |
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av_assert0(0); |
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} |
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d = d * (max - min) + min; |
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✗✗✓ |
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switch (sample_fmt) { |
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case AV_SAMPLE_FMT_FLT: { |
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float *fp = (float *)table; |
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*fp++ = (float)d; |
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table = fp; |
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continue; } |
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case AV_SAMPLE_FMT_DBL: { |
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double *dp = (double *)table; |
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*dp++ = d; |
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table = dp; |
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continue; } |
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} |
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✗✓ |
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d += d < 0 ? -0.5 : 0.5; |
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✗✓✗ |
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switch (sample_fmt) { |
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case AV_SAMPLE_FMT_S16: { |
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int16_t *sp = table; |
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*sp++ = (int16_t)d; |
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table = sp; |
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continue; } |
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case AV_SAMPLE_FMT_S32: { |
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int32_t *ip = table; |
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*ip++ = (int32_t)d; |
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table = ip; |
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continue; } |
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default: |
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av_assert0(0); |
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} |
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} |
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} |