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