vd_lavc: fix recently broken hardware decode fallback

This is a dataflow issue caused by the filters change. When the fallback
happens, vd_lavc does not return a frame, but also does not accept a new
packet, which confuses lavc_process(). Fix this by immediately retrying
to feed the buffered packet and decode a frame on fallback.

Fixes #5489.

1 files changed, 16 insertions, 7 deletions

diff --git a/video/decode/vd_lavc.c b/video/decode/vd_lavc.c
index 1aaca6b335..b306e57ffa 100644
--- a/video/decode/vd_lavc.c
+++ b/video/decode/vd_lavc.c
@@ -976,18 +976,24 @@ static bool do_send_packet(struct mp_filter *vd, struct demux_packet *pkt)
     return true;
 }
 
-static bool send_packet(struct mp_filter *vd, struct demux_packet *pkt)
+static bool send_queued(struct mp_filter *vd)
 {
     vd_ffmpeg_ctx *ctx = vd->priv;
 
-    if (ctx->num_requeue_packets) {
-        if (do_send_packet(vd, ctx->requeue_packets[0])) {
-            talloc_free(ctx->requeue_packets[0]);
-            MP_TARRAY_REMOVE_AT(ctx->requeue_packets, ctx->num_requeue_packets, 0);
-        }
-        return false;
+    while (ctx->num_requeue_packets && do_send_packet(vd, ctx->requeue_packets[0]))
+    {
+        talloc_free(ctx->requeue_packets[0]);
+        MP_TARRAY_REMOVE_AT(ctx->requeue_packets, ctx->num_requeue_packets, 0);
     }
 
+    return ctx->num_requeue_packets == 0;
+}
+
+static bool send_packet(struct mp_filter *vd, struct demux_packet *pkt)
+{
+    if (!send_queued(vd))
+        return false;
+
     return do_send_packet(vd, pkt);
 }
 
@@ -1052,6 +1058,9 @@ static bool receive_frame(struct mp_filter *vd, struct mp_frame *out_frame)
 
         ctx->requeue_packets = pkts;
         ctx->num_requeue_packets = num_pkts;
+
+        send_queued(vd);
+        progress = decode_frame(vd);
     }
 
     if (!ctx->num_delay_queue)