/* adpcm.h  codex functions for MS_ADPCM data *          (hopefully) provides interoperability with *          Microsoft's ADPCM format, but, as usual, *          see LACK-OF-WARRANTY information below. * *      Copyright (C) 1999 Stanley J. Brooks <stabro@megsinet.net> * * This library 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. * * This library 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 this library; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA * */#include "sox.h" #ifndef SAMPL#define SAMPL short#endif /* default coef sets */extern const short lsx_ms_adpcm_i_coef[7][2]; extern void *lsx_ms_adpcm_alloc(unsigned chans); /* lsx_ms_adpcm_block_expand_i() outputs interleaved samples into one output buffer */extern const char *lsx_ms_adpcm_block_expand_i(	void *priv,	unsigned chans,          /* total channels             */	int nCoef,	const short *coef,	const unsigned char *ibuff,/* input buffer[blockAlign]   */	SAMPL *obuff,       /* output samples, n*chans    */	int n               /* samples to decode PER channel, REQUIRE n % 8 == 1  */); extern void lsx_ms_adpcm_block_mash_i(	unsigned chans,          /* total channels */	const SAMPL *ip,    /* ip[n*chans] is interleaved input samples */	int n,              /* samples to encode PER channel, REQUIRE */	int *st,            /* input/output steps, 16<=st[i] */	unsigned char *obuff,      /* output buffer[blockAlign] */	int blockAlign      /* >= 7*chans + n/2          */); /* Some helper functions for computing samples/block and blockalign */ /* * lsx_ms_adpcm_samples_in(dataLen, chans, blockAlign, samplesPerBlock) *  returns the number of samples/channel which would be *  in the dataLen, given the other parameters ... *  if input samplesPerBlock is 0, then returns the max *  samplesPerBlock which would go into a block of size blockAlign *  Yes, it is confusing usage. */extern size_t lsx_ms_adpcm_samples_in(	size_t dataLen,	size_t chans,	size_t blockAlign,	size_t samplesPerBlock); /* * size_t lsx_ms_adpcm_bytes_per_block(chans, samplesPerBlock) *   return minimum blocksize which would be required *   to encode number of chans with given samplesPerBlock */extern size_t lsx_ms_adpcm_bytes_per_block(	size_t chans,	size_t samplesPerBlock);