1 /* 2 ** Copyright (C) 1999-2011 Erik de Castro Lopo <erikd@mega-nerd.com> 3 ** 4 ** This program is free software; you can redistribute it and/or modify 5 ** it under the terms of the GNU Lesser General Public License as published by 6 ** the Free Software Foundation; either version 2.1 of the License, or 7 ** (at your option) any later version. 8 ** 9 ** This program is distributed in the hope that it will be useful, 10 ** but WITHOUT ANY WARRANTY; without even the implied warranty of 11 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 ** GNU Lesser General Public License for more details. 13 ** 14 ** You should have received a copy of the GNU Lesser General Public License 15 ** along with this program; if not, write to the Free Software 16 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 */ 18 19 /* 20 ** This file is not the same as the original file from Sun Microsystems. Nearly 21 ** all the original definitions and function prototypes that were in the file 22 ** of this name have been moved to g72x_priv.h. 23 */ 24 25 #ifndef G72X_HEADER_FILE 26 #define G72X_HEADER_FILE 27 28 /* 29 ** Number of samples per block to process. 30 ** Must be a common multiple of possible bits per sample : 2, 3, 4, 5 and 8. 31 */ 32 #define G72x_BLOCK_SIZE (3 * 5 * 8) 33 34 /* 35 ** Identifiers for the differing kinds of G72x ADPCM codecs. 36 ** The identifiers also define the number of encoded bits per sample. 37 */ 38 39 enum 40 { G723_16_BITS_PER_SAMPLE = 2, 41 G723_24_BITS_PER_SAMPLE = 3, 42 G723_40_BITS_PER_SAMPLE = 5, 43 44 G721_32_BITS_PER_SAMPLE = 4, 45 G721_40_BITS_PER_SAMPLE = 5, 46 47 G723_16_SAMPLES_PER_BLOCK = G72x_BLOCK_SIZE, 48 G723_24_SAMPLES_PER_BLOCK = G723_24_BITS_PER_SAMPLE * (G72x_BLOCK_SIZE / G723_24_BITS_PER_SAMPLE), 49 G723_40_SAMPLES_PER_BLOCK = G723_40_BITS_PER_SAMPLE * (G72x_BLOCK_SIZE / G723_40_BITS_PER_SAMPLE), 50 51 G721_32_SAMPLES_PER_BLOCK = G72x_BLOCK_SIZE, 52 G721_40_SAMPLES_PER_BLOCK = G721_40_BITS_PER_SAMPLE * (G72x_BLOCK_SIZE / G721_40_BITS_PER_SAMPLE), 53 54 G723_16_BYTES_PER_BLOCK = (G723_16_BITS_PER_SAMPLE * G72x_BLOCK_SIZE) / 8, 55 G723_24_BYTES_PER_BLOCK = (G723_24_BITS_PER_SAMPLE * G72x_BLOCK_SIZE) / 8, 56 G723_40_BYTES_PER_BLOCK = (G723_40_BITS_PER_SAMPLE * G72x_BLOCK_SIZE) / 8, 57 58 G721_32_BYTES_PER_BLOCK = (G721_32_BITS_PER_SAMPLE * G72x_BLOCK_SIZE) / 8, 59 G721_40_BYTES_PER_BLOCK = (G721_40_BITS_PER_SAMPLE * G72x_BLOCK_SIZE) / 8 60 } ; 61 62 /* Forward declaration of of g72x_state. */ 63 64 struct g72x_state ; 65 66 /* External function definitions. */ 67 68 struct g72x_state * g72x_reader_init (int codec, int *blocksize, int *samplesperblock) ; 69 struct g72x_state * g72x_writer_init (int codec, int *blocksize, int *samplesperblock) ; 70 /* 71 ** Initialize the ADPCM state table for the given codec. 72 ** Return 0 on success, 1 on fail. 73 */ 74 75 int g72x_decode_block (struct g72x_state *pstate, const unsigned char *block, short *samples) ; 76 /* 77 ** The caller fills data->block with data->bytes bytes before calling the 78 ** function. The value data->bytes must be an integer multiple of 79 ** data->blocksize and be <= data->max_bytes. 80 ** When it returns, the caller can read out data->samples samples. 81 */ 82 83 int g72x_encode_block (struct g72x_state *pstate, short *samples, unsigned char *block) ; 84 /* 85 ** The caller fills state->samples some integer multiple data->samples_per_block 86 ** (up to G72x_BLOCK_SIZE) samples before calling the function. 87 ** When it returns, the caller can read out bytes encoded bytes. 88 */ 89 90 #endif /* !G72X_HEADER_FILE */ 91 92