1 files changed, 90 insertions, 0 deletions
diff --git a/filters/f_auto_filters.c b/filters/f_auto_filters.c
index eac6f745ca..b9f32026d5 100644
--- a/filters/f_auto_filters.c
+++ b/filters/f_auto_filters.c
@@ -242,3 +242,93 @@ struct mp_filter *mp_autorotate_create(struct mp_filter *parent)
 
     return f;
 }
+
+struct aspeed_priv {
+    struct mp_subfilter sub;
+    double cur_speed;
+};
+
+static void aspeed_process(struct mp_filter *f)
+{
+    struct aspeed_priv *p = f->priv;
+
+    if (!mp_subfilter_read(&p->sub))
+        return;
+
+    if (fabs(p->cur_speed - 1.0) < 1e-8) {
+        if (p->sub.filter)
+            MP_VERBOSE(f, "removing scaletempo\n");
+        if (!mp_subfilter_drain_destroy(&p->sub))
+            return;
+    } else if (!p->sub.filter) {
+        MP_VERBOSE(f, "adding scaletempo\n");
+        p->sub.filter =
+            mp_create_user_filter(f, MP_OUTPUT_CHAIN_AUDIO, "scaletempo", NULL);
+        if (!p->sub.filter) {
+            MP_ERR(f, "could not create scaletempo filter\n");
+            mp_subfilter_continue(&p->sub);
+            return;
+        }
+    }
+
+    if (p->sub.filter) {
+        struct mp_filter_command cmd = {
+            .type = MP_FILTER_COMMAND_SET_SPEED,
+            .speed = p->cur_speed,
+        };
+        mp_filter_command(p->sub.filter, &cmd);
+    }
+
+    mp_subfilter_continue(&p->sub);
+}
+
+static bool aspeed_command(struct mp_filter *f, struct mp_filter_command *cmd)
+{
+    struct aspeed_priv *p = f->priv;
+
+    if (cmd->type == MP_FILTER_COMMAND_SET_SPEED) {
+        p->cur_speed = cmd->speed;
+        return true;
+    }
+
+    return false;
+}
+
+static void aspeed_reset(struct mp_filter *f)
+{
+    struct aspeed_priv *p = f->priv;
+
+    mp_subfilter_reset(&p->sub);
+}
+
+static void aspeed_destroy(struct mp_filter *f)
+{
+    struct aspeed_priv *p = f->priv;
+
+    mp_subfilter_reset(&p->sub);
+    TA_FREEP(&p->sub.filter);
+}
+
+static const struct mp_filter_info aspeed_filter = {
+    .name = "autoaspeed",
+    .priv_size = sizeof(struct aspeed_priv),
+    .command = aspeed_command,
+    .process = aspeed_process,
+    .reset = aspeed_reset,
+    .destroy = aspeed_destroy,
+};
+
+struct mp_filter *mp_autoaspeed_create(struct mp_filter *parent)
+{
+    struct mp_filter *f = mp_filter_create(parent, &aspeed_filter);
+    if (!f)
+        return NULL;
+
+    struct aspeed_priv *p = f->priv;
+    p->cur_speed = 1.0;
+
+    p->sub.in = mp_filter_add_pin(f, MP_PIN_IN, "in");
+    p->sub.out = mp_filter_add_pin(f, MP_PIN_OUT, "out");
+
+    return f;
+}