11.1 vsip_dfir_create_p - Create a FIR Filter

typedef enum _vsip_symmetry { 
  VSIP_NONSYM            = 0, 
  VSIP_SYM_EVEN_LEN_ODD  = 1, 
  VSIP_SYM_EVEN_LEN_EVEN = 2 
} vsip_symmetry; 
 
typedef enum _vsip_obj_state { 
  VSIP_STATE_NO_SAVE = 1, 
  VSIP_STATE_SAVE    = 2 
} vsip_obj_state; 
 
typedef enum _vsip_alg_hint { 
  VSIP_ALG_TIME  = 0, 
  VSIP_ALG_SPACE = 1, 
  VSIP_ALG_NOISE = 2 
} vsip_alg_hint; 
 
vsip_fir_f *vsip_fir_create_f(const vsip_vview_f *kernel, vsip_symmetry symm, 
                              vsip_length n, vsip_length d, 
                              vsip_obj_state state, 
                              vsip_length ntimes, vsip_alg_hint hint); 
vsip_fir_d *vsip_fir_create_d(const vsip_vview_d *kernel, vsip_symmetry symm, 
                              vsip_length n, vsip_length d, 
                              vsip_obj_state state, 
                              vsip_length ntimes, vsip_alg_hint hint); 
vsip_cfir_f *vsip_cfir_create_f(const vsip_cvview_f *kernel, vsip_symmetry symm, 
                                vsip_length n, vsip_length d, 
                                vsip_obj_state state, 
                                vsip_length ntimes, vsip_alg_hint hint); 
vsip_cfir_d *vsip_cfir_create_d(const vsip_cvview_d *kernel, vsip_symmetry symm, 
                                vsip_length n, vsip_length d, 
                                vsip_obj_state state, 
                                vsip_length ntimes, vsip_alg_hint hint);

Description

This function creates a FIR (Finite Impulse Response) filter with the specified kernel, symmetry, length, decimation factor, state, number of times to apply the filter, and algorithm hint.

Parameters

• const vsip_dvview_p* kernel: Pointer to the kernel vector view.

• vsip_symmetry symm: Symmetry of the filter kernel.

  • VSIP_NOSYM - No symmetry

  • VSIP_SYM_EVEN_LEN_ODD - Odd symmetry

  • VSIP_SYM_EVEN_LEN_EVEN - Even symmetry

• vsip_length n: Length of the filter.

• vsip_length d: Decimation factor.

• vsip_obj_state state: State of the filter object.

  • VSIP_STATE_NO_SAVE - Do not save state

  • VSIP_STATE_SAVE - Save state

• vsip_length ntimes: Number of times to apply the filter.

• vsip_alg_hint hint: Algorithm hint for the filter.

  • VSIP_ALG_TIME - Optimize for time

  • VSIP_ALG_SPACE - Optimize for memory usage

  • VSIP_ALG_NOISE - Optimize for noise

Return Value

• On success, a pointer to the newly created FIR filter object is returned.

• On error, NULL is returned.

Example

vsip_vview_f *kernel_view; 
vsip_symmetry symm = VSIP_NONSYM; 
vsip_length length = 10; 
vsip_length decimation = 1; 
vsip_obj_state state = VSIP_STATE_SAVE; 
vsip_length ntimes = 1; 
vsip_alg_hint hint = VSIP_ALG_TIME; 
vsip_fir_f *fir_filter; 
 
// Assuming kernel_view has been properly initialized 
fir_filter = vsip_fir_create_f(kernel_view, symm, length, decimation, state, ntimes, hint); 
 
if (fir_filter == NULL) { 
    // Handle error 
}