55 lines
1.7 KiB
C
55 lines
1.7 KiB
C
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/*
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libltc - en+decode linear timecode
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Copyright (C) 2006-2012 Robin Gareus <robin@gareus.org>
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as
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published by the Free Software Foundation, either version 3 of the
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License, or (at your option) any later version.
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This program 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
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library.
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If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "ltc/ltc.h"
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#ifndef SAMPLE_CENTER // also defined in encoder.h
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#define SAMPLE_CENTER 128 // unsigned 8 bit.
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#endif
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struct LTCDecoder {
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LTCFrameExt* queue;
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int queue_len;
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int queue_read_off;
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int queue_write_off;
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unsigned char biphase_state;
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unsigned char biphase_prev;
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unsigned char snd_to_biphase_state;
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int snd_to_biphase_cnt; ///< counts the samples in the current period
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int snd_to_biphase_lmt; ///< specifies when a state-change is considered biphase-clock or 2*biphase-clock
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double snd_to_biphase_period; ///< track length of a period - used to set snd_to_biphase_lmt
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ltcsnd_sample_t snd_to_biphase_min;
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ltcsnd_sample_t snd_to_biphase_max;
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unsigned short decoder_sync_word;
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LTCFrame ltc_frame;
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int bit_cnt;
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ltc_off_t frame_start_off;
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ltc_off_t frame_start_prev;
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float biphase_tics[LTC_FRAME_BIT_COUNT];
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int biphase_tic;
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};
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void decode_ltc(LTCDecoder *d, ltcsnd_sample_t *sound, size_t size, ltc_off_t posinfo);
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