avfilter/af_aderivative: add timeline support

libavfilter/af_aderivative.c

@@ -16,6 +16,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include "libavutil/opt.h"
 #include "audio.h"
 #include "avfilter.h"
 #include "internal.h"
@@ -103,8 +104,18 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
     AVFilterContext *ctx = inlink->dst;
     ADerivativeContext *s = ctx->priv;
     AVFilterLink *outlink = ctx->outputs[0];
-    AVFrame *out = ff_get_audio_buffer(outlink, in->nb_samples);
+    AVFrame *out;
 
+    if (ctx->is_disabled) {
+        if (s->prev)
+            av_samples_set_silence(s->prev->extended_data, 0, 1,
+                                   s->prev->channels,
+                                   s->prev->format);
+
+        return ff_filter_frame(outlink, in);
+    }
+
+    out = ff_get_audio_buffer(outlink, in->nb_samples);
     if (!out) {
         av_frame_free(&in);
         return AVERROR(ENOMEM);
@@ -149,23 +160,33 @@ static const AVFilterPad aderivative_outputs[] = {
     },
 };
 
+static const AVOption aderivative_options[] = {
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS_EXT(aderivative, "aderivative/aintegral", aderivative_options);
+
 const AVFilter ff_af_aderivative = {
     .name          = "aderivative",
     .description   = NULL_IF_CONFIG_SMALL("Compute derivative of input audio."),
     .priv_size     = sizeof(ADerivativeContext),
+    .priv_class    = &aderivative_class,
     .uninit        = uninit,
     FILTER_INPUTS(aderivative_inputs),
     FILTER_OUTPUTS(aderivative_outputs),
     FILTER_SAMPLEFMTS(AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_FLTP,
                       AV_SAMPLE_FMT_S32P, AV_SAMPLE_FMT_DBLP),
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
 };
 
 const AVFilter ff_af_aintegral = {
     .name          = "aintegral",
     .description   = NULL_IF_CONFIG_SMALL("Compute integral of input audio."),
     .priv_size     = sizeof(ADerivativeContext),
+    .priv_class    = &aderivative_class,
     .uninit        = uninit,
     FILTER_INPUTS(aderivative_inputs),
     FILTER_OUTPUTS(aderivative_outputs),
     FILTER_SAMPLEFMTS(AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_DBLP),
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
 };