v4l2slh264dec: Prevent spurious renegotiation

Don't let downstream cause a renegotiation at random point in time. This would
lead to spurious renegotiation and the decoder state may not be recoverable.

diff --git a/sys/v4l2codecs/gstv4l2codech264dec.c b/sys/v4l2codecs/gstv4l2codech264dec.c
index 24922e8..73071f7 100644 (file)
--- a/sys/v4l2codecs/gstv4l2codech264dec.c
+++ b/sys/v4l2codecs/gstv4l2codech264dec.c
@@ -65,6 +65,7 @@ struct _GstV4l2CodecH264Dec
   GstV4l2CodecPool *src_pool;
   gint min_pool_size;
   gboolean has_videometa;
+  gboolean need_negotiation;
 
   struct v4l2_ctrl_h264_sps sps;
   struct v4l2_ctrl_h264_pps pps;
@@ -137,6 +138,11 @@ gst_v4l2_codec_h264_dec_negotiate (GstVideoDecoder * decoder)
   GstV4l2CodecH264Dec *self = GST_V4L2_CODEC_H264_DEC (decoder);
   GstH264Decoder *h264dec = GST_H264_DECODER (decoder);
 
+  /* Ignore downstream renegotiation request. */
+  if (!self->need_negotiation)
+    return TRUE;
+  self->need_negotiation = FALSE;
+
   GST_DEBUG_OBJECT (self, "Negotiate");
 
   if (self->sink_allocator)
@@ -449,6 +455,7 @@ gst_v4l2_codec_h264_dec_new_sequence (GstH264Decoder * decoder,
   gst_v4l2_codec_h264_dec_fill_sequence (self, sps);
 
   if (negotiation_needed) {
+    self->need_negotiation = TRUE;
     if (!gst_video_decoder_negotiate (GST_VIDEO_DECODER (self))) {
       GST_ERROR_OBJECT (self, "Failed to negotiate with downstream");
       return FALSE;