repositories / deb_ffmpeg.git / blame
| Commit | Line | Data |
|---|---|---|
| 2ba45a60 DM |
1 | /* |
| 2 | * ADX ADPCM codecs | |
| 3 | * Copyright (c) 2001,2003 BERO | |
| 4 | * | |
| 5 | * This file is part of FFmpeg. | |
| 6 | * | |
| 7 | * FFmpeg is free software; you can redistribute it and/or | |
| 8 | * modify it under the terms of the GNU Lesser General Public | |
| 9 | * License as published by the Free Software Foundation; either | |
| 10 | * version 2.1 of the License, or (at your option) any later version. | |
| 11 | * | |
| 12 | * FFmpeg is distributed in the hope that it will be useful, | |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 15 | * Lesser General Public License for more details. | |
| 16 | * | |
| 17 | * You should have received a copy of the GNU Lesser General Public | |
| 18 | * License along with FFmpeg; if not, write to the Free Software | |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| 20 | */ | |
| 21 | ||
| 22 | /** | |
| 23 | * @file | |
| 24 | * SEGA CRI adx codecs. | |
| 25 | * | |
| 26 | * Reference documents: | |
| 27 | * http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html | |
| 28 | * adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/ | |
| 29 | */ | |
| 30 | ||
| 31 | #ifndef AVCODEC_ADX_H | |
| 32 | #define AVCODEC_ADX_H | |
| 33 | ||
| 34 | #include <stdint.h> | |
| 35 | ||
| 36 | #include "avcodec.h" | |
| 37 | ||
| 38 | typedef struct ADXChannelState { | |
| 39 | int s1,s2; | |
| 40 | } ADXChannelState; | |
| 41 | ||
| 42 | typedef struct ADXContext { | |
| 43 | int channels; | |
| 44 | ADXChannelState prev[2]; | |
| 45 | int header_parsed; | |
| 46 | int eof; | |
| 47 | int cutoff; | |
| 48 | int coeff[2]; | |
| 49 | } ADXContext; | |
| 50 | ||
| 51 | #define COEFF_BITS 12 | |
| 52 | ||
| 53 | #define BLOCK_SIZE 18 | |
| 54 | #define BLOCK_SAMPLES 32 | |
| 55 | ||
| 56 | /** | |
| 57 | * Calculate LPC coefficients based on cutoff frequency and sample rate. | |
| 58 | * | |
| 59 | * @param cutoff cutoff frequency | |
| 60 | * @param sample_rate sample rate | |
| 61 | * @param bits number of bits used to quantize coefficients | |
| 62 | * @param[out] coeff 2 quantized LPC coefficients | |
| 63 | */ | |
| 64 | void ff_adx_calculate_coeffs(int cutoff, int sample_rate, int bits, int *coeff); | |
| 65 | ||
| 66 | /** | |
| 67 | * Decode ADX stream header. | |
| 68 | * Sets avctx->channels and avctx->sample_rate. | |
| 69 | * | |
| 70 | * @param avctx codec context | |
| 71 | * @param buf header data | |
| 72 | * @param bufsize data size, should be at least 24 bytes | |
| 73 | * @param[out] header_size size of ADX header | |
| 74 | * @param[out] coeff 2 LPC coefficients, can be NULL | |
| 75 | * @return data offset or negative error code if header is invalid | |
| 76 | */ | |
| 77 | int ff_adx_decode_header(AVCodecContext *avctx, const uint8_t *buf, | |
| 78 | int bufsize, int *header_size, int *coeff); | |
| 79 | ||
| 80 | #endif /* AVCODEC_ADX_H */ |