avfilter/af_asubboost: add timeline and slice threading support

libavfilter/af_asubboost.c

@@ -37,7 +37,7 @@ typedef struct ASubBoostContext {
     double a0, a1, a2;
     double b0, b1, b2;
 
-    int write_pos;
+    int *write_pos;
     int buffer_samples;
 
     AVFrame *w;
@@ -105,44 +105,42 @@ static int config_input(AVFilterLink *inlink)
 
     s->buffer = ff_get_audio_buffer(inlink, inlink->sample_rate / 10);
     s->w = ff_get_audio_buffer(inlink, 2);
-    if (!s->buffer || !s->w)
+    s->write_pos = av_calloc(inlink->channels, sizeof(*s->write_pos));
+    if (!s->buffer || !s->w || !s->write_pos)
         return AVERROR(ENOMEM);
 
     return get_coeffs(ctx);
 }
 
-static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+typedef struct ThreadData {
+    AVFrame *in, *out;
+} ThreadData;
+
+static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
 {
-    AVFilterContext *ctx = inlink->dst;
-    AVFilterLink *outlink = ctx->outputs[0];
     ASubBoostContext *s = ctx->priv;
-    const double wet = s->wet_gain, dry = s->dry_gain, feedback = s->feedback, decay = s->decay;
+    ThreadData *td = arg;
+    AVFrame *out = td->out;
+    AVFrame *in = td->in;
+    const double wet = ctx->is_disabled ? 0. : s->wet_gain;
+    const double dry = ctx->is_disabled ? 1. : s->dry_gain;
+    const double feedback = s->feedback, decay = s->decay;
     const double b0 = s->b0;
     const double b1 = s->b1;
     const double b2 = s->b2;
     const double a1 = -s->a1;
     const double a2 = -s->a2;
-    int write_pos;
-    AVFrame *out;
+    const int start = (in->channels * jobnr) / nb_jobs;
+    const int end = (in->channels * (jobnr+1)) / nb_jobs;
+    const int buffer_samples = s->buffer_samples;
 
-    if (av_frame_is_writable(in)) {
-        out = in;
-    } else {
-        out = ff_get_audio_buffer(outlink, in->nb_samples);
-        if (!out) {
-            av_frame_free(&in);
-            return AVERROR(ENOMEM);
-        }
-        av_frame_copy_props(out, in);
-    }
-
-    for (int ch = 0; ch < in->channels; ch++) {
+    for (int ch = start; ch < end; ch++) {
         const double *src = (const double *)in->extended_data[ch];
         double *dst = (double *)out->extended_data[ch];
         double *buffer = (double *)s->buffer->extended_data[ch];
         double *w = (double *)s->w->extended_data[ch];
+        int write_pos = s->write_pos[ch];
 
-        write_pos = s->write_pos;
         for (int n = 0; n < in->nb_samples; n++) {
             double out_sample;
 
@@ -153,12 +151,37 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
             buffer[write_pos] = buffer[write_pos] * decay + out_sample * feedback;
             dst[n] = src[n] * dry + buffer[write_pos] * wet;
 
-            if (++write_pos >= s->buffer_samples)
+            if (++write_pos >= buffer_samples)
                 write_pos = 0;
         }
+
+        s->write_pos[ch] = write_pos;
+    }
+
+    return 0;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+    AVFilterContext *ctx = inlink->dst;
+    AVFilterLink *outlink = ctx->outputs[0];
+    ThreadData td;
+    AVFrame *out;
+
+    if (av_frame_is_writable(in)) {
+        out = in;
+    } else {
+        out = ff_get_audio_buffer(outlink, in->nb_samples);
+        if (!out) {
+            av_frame_free(&in);
+            return AVERROR(ENOMEM);
+        }
+        av_frame_copy_props(out, in);
     }
 
-    s->write_pos = write_pos;
+    td.in = in; td.out = out;
+    ctx->internal->execute(ctx, filter_channels, &td, NULL, FFMIN(inlink->channels,
+                                                            ff_filter_get_nb_threads(ctx)));
 
     if (out != in)
         av_frame_free(&in);
@@ -171,6 +194,7 @@ static av_cold void uninit(AVFilterContext *ctx)
 
     av_frame_free(&s->buffer);
     av_frame_free(&s->w);
+    av_freep(&s->write_pos);
 }
 
 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
@@ -229,4 +253,6 @@ AVFilter ff_af_asubboost = {
     .inputs         = inputs,
     .outputs        = outputs,
     .process_command = process_command,
+    .flags           = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL |
+                       AVFILTER_FLAG_SLICE_THREADS,
 };