diff options
| -rw-r--r-- | libavcodec/iirfilter.c | 102 | ||||
| -rw-r--r-- | libavcodec/iirfilter.h | 17 |
2 files changed, 80 insertions, 39 deletions
diff --git a/libavcodec/iirfilter.c b/libavcodec/iirfilter.c index 65d9f89386..e37fd810d6 100644 --- a/libavcodec/iirfilter.c +++ b/libavcodec/iirfilter.c @@ -118,48 +118,74 @@ av_cold struct FFIIRFilterState* ff_iir_filter_init_state(int order) return s; } -#define FILTER(i0, i1, i2, i3) \ - in = *src * c->gain \ - + c->cy[0]*s->x[i0] + c->cy[1]*s->x[i1] \ - + c->cy[2]*s->x[i2] + c->cy[3]*s->x[i3]; \ - res = (s->x[i0] + in )*1 \ - + (s->x[i1] + s->x[i3])*4 \ - + s->x[i2] *6; \ - *dst = av_clip_int16(lrintf(res)); \ - s->x[i0] = in; \ - src += sstep; \ - dst += dstep; \ +#define CONV_S16(dest, source) dest = av_clip_int16(lrintf(source)); + +#define CONV_FLT(dest, source) dest = source; + +#define FILTER_BW_O4_1(i0, i1, i2, i3, fmt) \ + in = *src0 * c->gain \ + + c->cy[0]*s->x[i0] + c->cy[1]*s->x[i1] \ + + c->cy[2]*s->x[i2] + c->cy[3]*s->x[i3]; \ + res = (s->x[i0] + in )*1 \ + + (s->x[i1] + s->x[i3])*4 \ + + s->x[i2] *6; \ + CONV_##fmt(*dst0, res) \ + s->x[i0] = in; \ + src0 += sstep; \ + dst0 += dstep; + +#define FILTER_BW_O4(type, fmt) { \ + int i; \ + const type *src0 = src; \ + type *dst0 = dst; \ + for (i = 0; i < size; i += 4) { \ + float in, res; \ + FILTER_BW_O4_1(0, 1, 2, 3, fmt); \ + FILTER_BW_O4_1(1, 2, 3, 0, fmt); \ + FILTER_BW_O4_1(2, 3, 0, 1, fmt); \ + FILTER_BW_O4_1(3, 0, 1, 2, fmt); \ + } \ +} + +#define FILTER_DIRECT_FORM_II(type, fmt) { \ + int i; \ + const type *src0 = src; \ + type *dst0 = dst; \ + for (i = 0; i < size; i++) { \ + int j; \ + float in, res; \ + in = *src0 * c->gain; \ + for(j = 0; j < c->order; j++) \ + in += c->cy[j] * s->x[j]; \ + res = s->x[0] + in + s->x[c->order >> 1] * c->cx[c->order >> 1]; \ + for(j = 1; j < c->order >> 1; j++) \ + res += (s->x[j] + s->x[c->order - j]) * c->cx[j]; \ + for(j = 0; j < c->order - 1; j++) \ + s->x[j] = s->x[j + 1]; \ + CONV_##fmt(*dst0, res) \ + s->x[c->order - 1] = in; \ + src0 += sstep; \ + dst0 += dstep; \ + } \ +} void ff_iir_filter(const struct FFIIRFilterCoeffs *c, struct FFIIRFilterState *s, int size, const int16_t *src, int sstep, int16_t *dst, int dstep) { - int i; - - if(c->order == 4){ - for(i = 0; i < size; i += 4){ - float in, res; + if (c->order == 4) { + FILTER_BW_O4(int16_t, S16) + } else { + FILTER_DIRECT_FORM_II(int16_t, S16) + } +} - FILTER(0, 1, 2, 3); - FILTER(1, 2, 3, 0); - FILTER(2, 3, 0, 1); - FILTER(3, 0, 1, 2); - } - }else{ - for(i = 0; i < size; i++){ - int j; - float in, res; - in = *src * c->gain; - for(j = 0; j < c->order; j++) - in += c->cy[j] * s->x[j]; - res = s->x[0] + in + s->x[c->order >> 1] * c->cx[c->order >> 1]; - for(j = 1; j < c->order >> 1; j++) - res += (s->x[j] + s->x[c->order - j]) * c->cx[j]; - for(j = 0; j < c->order - 1; j++) - s->x[j] = s->x[j + 1]; - *dst = av_clip_int16(lrintf(res)); - s->x[c->order - 1] = in; - src += sstep; - dst += dstep; - } +void ff_iir_filter_flt(const struct FFIIRFilterCoeffs *c, + struct FFIIRFilterState *s, int size, + const float *src, int sstep, void *dst, int dstep) +{ + if (c->order == 4) { + FILTER_BW_O4(float, FLT) + } else { + FILTER_DIRECT_FORM_II(float, FLT) } } diff --git a/libavcodec/iirfilter.h b/libavcodec/iirfilter.h index f660955403..fd26166862 100644 --- a/libavcodec/iirfilter.h +++ b/libavcodec/iirfilter.h @@ -87,7 +87,7 @@ void ff_iir_filter_free_coeffs(struct FFIIRFilterCoeffs *coeffs); void ff_iir_filter_free_state(struct FFIIRFilterState *state); /** - * Perform lowpass filtering on input samples. + * Perform IIR filtering on signed 16-bit input samples. * * @param coeffs pointer to filter coefficients * @param state pointer to filter state @@ -100,4 +100,19 @@ void ff_iir_filter_free_state(struct FFIIRFilterState *state); void ff_iir_filter(const struct FFIIRFilterCoeffs *coeffs, struct FFIIRFilterState *state, int size, const int16_t *src, int sstep, int16_t *dst, int dstep); +/** + * Perform IIR filtering on floating-point input samples. + * + * @param coeffs pointer to filter coefficients + * @param state pointer to filter state + * @param size input length + * @param src source samples + * @param sstep source stride + * @param dst filtered samples (destination may be the same as input) + * @param dstep destination stride + */ +void ff_iir_filter_flt(const struct FFIIRFilterCoeffs *coeffs, + struct FFIIRFilterState *state, int size, + const float *src, int sstep, void *dst, int dstep); + #endif /* AVCODEC_IIRFILTER_H */ |