WSJT-X/libm65/qracodes/npfwht.h
2018-10-19 15:55:29 -04:00

46 lines
1.6 KiB
C

// np_fwht.h
// Basic implementation of the Fast Walsh-Hadamard Transforms
//
// (c) 2016 - Nico Palermo, IV3NWV - Microtelecom Srl, Italy
// ------------------------------------------------------------------------------
// This file is part of the qracodes project, a Forward Error Control
// encoding/decoding package based on Q-ary RA (repeat and accumulate) LDPC codes.
//
// qracodes 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 3 of the License, or
// (at your option) any later version.
// qracodes 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 qracodes source distribution.
// If not, see <http://www.gnu.org/licenses/>.
#ifndef _npfwht_h_
#define _npfwht_h_
#ifdef __cplusplus
extern "C" {
#endif
void np_fwht(int nlogdim, float *dst, float *src);
// Compute the Walsh-Hadamard transform of the given data up to a
// 64-dimensional transform
//
// Input parameters:
// nlogdim: log2 of the transform size. Must be in the range [0..6]
// src : pointer to the input data buffer.
// dst : pointer to the output data buffer.
//
// src and dst must point to preallocated data buffers of size 2^nlogdim*sizeof(float)
// src and dst buffers can overlap
#ifdef __cplusplus
}
#endif
#endif // _npfwht_