ref: 613f50d018d73308428dda8c610066a726e1a95e
dir: /src/ima_rw.h/
/* ima_rw.h -- codex utilities for WAV_FORMAT_IMA_ADPCM Copyright (C) 1999 Stanley J. Brooks <stabro@megsinet.net> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifndef SAMPL # define SAMPL short #endif /* #undef STRICT_IMA makes code a bit faster, but not * strictly compatible with the real IMA spec, which * defines an encoding on approximate multiply/divide * using shift/adds instead of the (now) faster mult/div * Probably the roundof inexactness is inaudibly small, * so you might consider it worthwhile to #undef STRICT_IMA */ #define STRICT_IMA /* #undef STRICT_IMA */ /* * call initImaTable() before any other Ima* functions, * to create the fast lookup tables */ extern void initImaTable(void); /* ImaBlockExpandI() outputs interleaved samples into one output buffer */ extern void ImaBlockExpandI( int chans, /* total channels */ const u_char *ibuff,/* input buffer[blockAlign] */ SAMPL *obuff, /* output samples, n*chans */ int n /* samples to decode PER channel, REQUIRE n % 8 == 1 */ ); /* ImaBlockExpandM() outputs non-interleaved samples into chan separate output buffers */ extern void ImaBlockExpandM( int chans, /* total channels */ const u_char *ibuff,/* input buffer[blockAlign] */ SAMPL **obuffs, /* chan output sample buffers, each takes n samples */ int n /* samples to decode PER channel, REQUIRE n % 8 == 1 */ ); extern void ImaMashChannel( int ch, /* channel number to encode, REQUIRE 0 <= ch < chans */ int chans, /* total channels */ const SAMPL *ip, /* ip[] is interleaved input samples */ int n, /* samples to encode PER channel, REQUIRE n % 8 == 1 */ int *st, /* input/output state, REQUIRE 0 <= *st <= ISSTMAX */ u_char *obuff, /* output buffer[blockAlign] */ int opt /* non-zero allows some cpu-intensive code to improve output */ );