ref: 8b07535150c66640c77af3bb97a023b4fc6f25b4
dir: /src/adpcm.h/
/* * adpcm.h */ #include "st.h" #ifndef SAMPL #define SAMPL short #endif /* default coef sets */ extern const short iCoef[7][2]; /* AdpcmBlockExpandI() outputs interleaved samples into one output buffer */ extern const char *AdpcmBlockExpandI( int chans, /* total channels */ int nCoef, const short *iCoef, 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 AdpcmBlockMashI( int 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 */ int opt /* non-zero allows some cpu-intensive code to improve output */ ); /* Some helper functions for computing samples/block and blockalign */ /* * AdpcmSamplesIn(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 st_size_t AdpcmSamplesIn( st_size_t dataLen, unsigned short chans, unsigned short blockAlign, unsigned short samplesPerBlock ); /* * st_size_t AdpcmBytesPerBlock(chans, samplesPerBlock) * return minimum blocksize which would be required * to encode number of chans with given samplesPerBlock */ extern st_size_t AdpcmBytesPerBlock( unsigned short chans, unsigned short samplesPerBlock );