ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Fri Oct 16 22:51:16 2020 +0200| [e704750a9f51b4d3fd9a334da75d781e18a9e00c] | committer: Paul B Mahol
avfilter/af_aiir: use transposed II form for biquad sections
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e704750a9f51b4d3fd9a334da75d781e18a9e00c
---
libavfilter/af_aiir.c | 48 ++++++++++++++++++------------------------------
1 file changed, 18 insertions(+), 30 deletions(-)
diff --git a/libavfilter/af_aiir.c b/libavfilter/af_aiir.c
index 4b6e867819..8900b0a7c4 100644
--- a/libavfilter/af_aiir.c
+++ b/libavfilter/af_aiir.c
@@ -40,8 +40,7 @@ typedef struct Pair {
typedef struct BiquadContext {
double a[3];
double b[3];
- double i1, i2;
- double o1, o2;
+ double w1, w2;
} BiquadContext;
typedef struct IIRChannel {
@@ -177,8 +176,9 @@ IIR_CH(s32p, int32_t, INT32_MIN, INT32_MAX, 1)
IIR_CH(fltp, float, -1., 1., 0)
IIR_CH(dblp, double, -1., 1., 0)
-#define SERIAL_IIR_CH(name, type, min, max, need_clipping) \
-static int iir_ch_serial_## name(AVFilterContext *ctx, void *arg, int ch, int nb_jobs) \
+#define SERIAL_IIR_CH(name, type, min, max, need_clipping) \
+static int iir_ch_serial_## name(AVFilterContext *ctx, void *arg, \
+ int ch, int nb_jobs) \
{ \
AudioIIRContext *s = ctx->priv; \
const double ig = s->dry_gain; \
@@ -201,19 +201,15 @@ static int iir_ch_serial_## name(AVFilterContext *ctx, void *arg, int ch, int nb
const double b0 = iir->biquads[i].b[0]; \
const double b1 = iir->biquads[i].b[1]; \
const double b2 = iir->biquads[i].b[2]; \
- double i1 = iir->biquads[i].i1; \
- double i2 = iir->biquads[i].i2; \
- double o1 = iir->biquads[i].o1; \
- double o2 = iir->biquads[i].o2; \
+ double w1 = iir->biquads[i].w1; \
+ double w2 = iir->biquads[i].w2; \
\
for (n = 0; n < in->nb_samples; n++) { \
double i0 = ig * (i ? dst[n] : src[n]); \
- double o0 = i0 * b0 + i1 * b1 + i2 * b2 + o1 * a1 + o2 * a2; \
+ double o0 = i0 * b0 + w1; \
\
- i2 = i1; \
- i1 = i0; \
- o2 = o1; \
- o1 = o0; \
+ w1 = b1 * i0 + w2 + a1 * o0; \
+ w2 = b2 * i0 + a2 * o0; \
o0 *= og * g; \
\
o0 = o0 * mix + imix * i0; \
@@ -227,10 +223,8 @@ static int iir_ch_serial_## name(AVFilterContext *ctx, void *arg, int ch, int nb
dst[n] = o0; \
} \
} \
- iir->biquads[i].i1 = i1; \
- iir->biquads[i].i2 = i2; \
- iir->biquads[i].o1 = o1; \
- iir->biquads[i].o2 = o2; \
+ iir->biquads[i].w1 = w1; \
+ iir->biquads[i].w2 = w2; \
} \
\
return 0; \
@@ -266,19 +260,15 @@ static int iir_ch_parallel_## name(AVFilterContext *ctx, void *arg, \
const double a2 = -iir->biquads[i].a[2]; \
const double b1 = iir->biquads[i].b[1]; \
const double b2 = iir->biquads[i].b[2]; \
- double i1 = iir->biquads[i].i1; \
- double i2 = iir->biquads[i].i2; \
- double o1 = iir->biquads[i].o1; \
- double o2 = iir->biquads[i].o2; \
+ double w1 = iir->biquads[i].w1; \
+ double w2 = iir->biquads[i].w2; \
\
for (n = 0; n < in->nb_samples; n++) { \
double i0 = ig * src[n]; \
- double o0 = i1 * b1 + i2 * b2 + o1 * a1 + o2 * a2; \
+ double o0 = w1; \
\
- i2 = i1; \
- i1 = i0; \
- o2 = o1; \
- o1 = o0; \
+ w1 = b1 * i0 + w2 + a1 * o0; \
+ w2 = b2 * i0 + a2 * o0; \
o0 *= og * g; \
o0 += dst[n]; \
\
@@ -292,10 +282,8 @@ static int iir_ch_parallel_## name(AVFilterContext *ctx, void *arg, \
dst[n] = o0; \
} \
} \
- iir->biquads[i].i1 = i1; \
- iir->biquads[i].i2 = i2; \
- iir->biquads[i].o1 = o1; \
- iir->biquads[i].o2 = o2; \
+ iir->biquads[i].w1 = w1; \
+ iir->biquads[i].w2 = w2; \
} \
\
for (n = 0; n < in->nb_samples; n++) { \