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68 lines
2.1 KiB
68 lines
2.1 KiB
/* |
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* Shared functions between AMR codecs |
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* |
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* Copyright (c) 2010 Marcelo Galvao Povoa |
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* |
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* This file is part of Libav. |
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* |
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* Libav 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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* Libav 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 Libav; 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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#ifndef AVCODEC_AMR_H |
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#define AVCODEC_AMR_H |
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#include "avcodec.h" |
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#ifdef AMR_USE_16BIT_TABLES |
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#define R_TABLE_TYPE uint16_t |
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#else |
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#define R_TABLE_TYPE uint8_t |
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#endif |
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/** |
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* Fill the frame structure variables from bitstream by parsing the |
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* given reordering table that uses the following format: |
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* |
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* Each field (16 bits) in the AMR Frame is stored as: |
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* - one byte for the number of bits in the field |
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* - one byte for the field index |
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* - then, one byte for each bit of the field (from most-significant to least) |
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* of the position of that bit in the AMR frame. |
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* |
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* @param out pointer to the frame struct |
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* @param size the size in bytes of the frame struct |
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* @param data input bitstream after the frame header |
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* @param ord_table the reordering table as above |
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*/ |
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static inline void ff_amr_bit_reorder(uint16_t *out, int size, |
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const uint8_t *data, |
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const R_TABLE_TYPE *ord_table) |
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{ |
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int field_size; |
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memset(out, 0, size); |
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while ((field_size = *ord_table++)) { |
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int field = 0; |
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int field_offset = *ord_table++; |
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while (field_size--) { |
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int bit = *ord_table++; |
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field <<= 1; |
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field |= data[bit >> 3] >> (bit & 7) & 1; |
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} |
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out[field_offset] = field; |
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} |
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} |
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#endif /* AVCODEC_AMR_H */
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