static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
{
AVFilterLink *outlink = inlink->dst->outputs[0];
int16_t *taps, *endin, *in, *out;
AVFrame *outsamples = ff_get_audio_buffer(inlink, insamples->nb_samples);
int len;
if (!outsamples) {
av_frame_free(&insamples);
return AVERROR(ENOMEM);
}
av_frame_copy_props(outsamples, insamples);
taps = ((EarwaxContext *)inlink->dst->priv)->taps;
out = (int16_t *)outsamples->data[0];
in = (int16_t *)insamples ->data[0];
len = FFMIN(NUMTAPS, 2*insamples->nb_samples);
// copy part of new input and process with saved input
memcpy(taps+NUMTAPS, in, len * sizeof(*taps));
out = scalarproduct(taps, taps + len, out);
// process current input
if (2*insamples->nb_samples >= NUMTAPS ){
endin = in + insamples->nb_samples * 2 - NUMTAPS;
scalarproduct(in, endin, out);
// save part of input for next round
memcpy(taps, endin, NUMTAPS * sizeof(*taps));
} else
memmove(taps, taps + 2*insamples->nb_samples, NUMTAPS * sizeof(*taps));
av_frame_free(&insamples);
return ff_filter_frame(outlink, outsamples);
}
static int filter_samples(AVFilterLink *inlink, AVFilterBufferRef *insamples)
{
AVFilterLink *outlink = inlink->dst->outputs[0];
int16_t *taps, *endin, *in, *out;
AVFilterBufferRef *outsamples =
ff_get_audio_buffer(inlink, AV_PERM_WRITE,
insamples->audio->nb_samples);
int ret;
avfilter_copy_buffer_ref_props(outsamples, insamples);
taps = ((EarwaxContext *)inlink->dst->priv)->taps;
out = (int16_t *)outsamples->data[0];
in = (int16_t *)insamples ->data[0];
// copy part of new input and process with saved input
memcpy(taps+NUMTAPS, in, NUMTAPS * sizeof(*taps));
out = scalarproduct(taps, taps + NUMTAPS, out);
// process current input
endin = in + insamples->audio->nb_samples * 2 - NUMTAPS;
out = scalarproduct(in, endin, out);
// save part of input for next round
memcpy(taps, endin, NUMTAPS * sizeof(*taps));
ret = ff_filter_samples(outlink, outsamples);
avfilter_unref_buffer(insamples);
return ret;
}
static double length(
double ax, double ay, double az )
{
return sqrt(
scalarproduct(
ax, ay, az,
ax, ay, az ) );
}
static double scalarproduct_v(
double const * const a,
double const * const b )
{
return scalarproduct(
a[0], a[1], a[2],
b[0], b[1], b[2] );
}
