biquadcascadedf1.h

00001 #ifndef _BIQUADCASCADEDF1_H_
00002 #define _BIQUADCASCADEDF1_H_
00003 
00004 #include "abstractfilter.h"
00005 namespace amakusa
00006 {
00007 /**
00008 * @brief Wrapper class of the arm_biquad_cascade_df1_f32() and the arm_biquad_cascade_df1_init_f32().
00009 * @details
00010 * To use this class, include amakusa.h
00011 *
00012 * The biquad filter is depicted as following. The pCoeff array has b0, b1, b2, a1, a2 parameter
00013 * by this order. If the stage is N, N blockes of these parameers are given. The length of pCoeff
00014 * is 5N. 
00015 * @code
00016 x[n]---+-- b0 -->+---------+---y[n]
00017        |         ^         |
00018        D         |         |
00019        +-- b1 -->+<-- a1 --+
00020        D         |         |
00021        +-- b2 -->+<-- a2 --+
00022 * @endcode
00023 */
00024     class BiQuadCascadeDF1 : public AbstractFilter
00025     {
00026     public:
00027             /**
00028             * @brief Constructor
00029             * @param[in] stages Number of the Bi-Quad stages. 
00030             * @param[in] pCoeff Ponter to the coefficients array.
00031             * @param[in] blockSize Maximum number of the samples to be given to run() method at onece. 
00032             */
00033         BiQuadCascadeDF1(uint16_t stages, float32_t *pCoeff, uint32_t block_size);
00034             /**
00035             * deconstructor
00036             */
00037         virtual ~BiQuadCascadeDF1();
00038             /**
00039             * @brief Run the filter.
00040             * @param[in] pSrc Pointer to the source buffer to be filtered.
00041             * @param[out] pDst Pointer to the destination buffer to store the filtered signal. 
00042             */
00043         virtual void run( float32_t *pSrc, float32_t *pDst );
00044     private:
00045         arm_biquad_casd_df1_inst_f32 state;
00046     };
00047     
00048 }
00049 
00050 #endif