qsvencoder: Workaround for invalid DTS with VP9

SDK runtime seems to report zero DTS for all frames in case of VP9 but
we don't need to use DTS for the codec.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2291>

diff --git a/subprojects/gst-plugins-bad/sys/qsv/gstqsvencoder.cpp b/subprojects/gst-plugins-bad/sys/qsv/gstqsvencoder.cpp
index e16a13a30bbfd1e4be87930b6a37d0e9a07687e0..3b6e7472be9852bfc24c6b798c18c4d3cf68f872 100644 (file)
--- a/subprojects/gst-plugins-bad/sys/qsv/gstqsvencoder.cpp
+++ b/subprojects/gst-plugins-bad/sys/qsv/gstqsvencoder.cpp
@@ -704,8 +704,8 @@ gst_qsv_encoder_finish_frame (GstQsvEncoder * self, GstQsvEncoderTask * task,
   mfxStatus status;
   mfxBitstream *bs;
   GstVideoCodecFrame *frame;
-  GstClockTime pts = GST_CLOCK_TIME_NONE;
-  GstClockTime dts = GST_CLOCK_TIME_NONE;
+  GstClockTime qsv_pts = GST_CLOCK_TIME_NONE;
+  GstClockTime qsv_dts = GST_CLOCK_TIME_NONE;
   GstBuffer *buffer;
   gboolean keyframe = FALSE;
   guint retry_count = 0;
@@ -750,8 +750,19 @@ gst_qsv_encoder_finish_frame (GstQsvEncoder * self, GstQsvEncoderTask * task,
   }
 
   bs = &task->bitstream;
-  pts = gst_qsv_timestamp_to_gst (bs->TimeStamp);
-  dts = gst_qsv_timestamp_to_gst ((mfxU64) bs->DecodeTimeStamp);
+  qsv_pts = gst_qsv_timestamp_to_gst (bs->TimeStamp);
+
+  /* SDK runtime seems to report zero DTS for all fraems in case of VP9.
+   * It sounds SDK bug, but we can workaround it safely because VP9 B-frame is
+   * not supported in this implementation.
+   *
+   * Also we perfer our nanoseconds timestamp instead of QSV's timescale.
+   * So let' ignore QSV's timescale for non-{h264,h265} cases.
+   *
+   * TODO: We may need to use DTS for MPEG2 (not implemented yet)
+   */
+  if (klass->codec_id == MFX_CODEC_AVC || klass->codec_id == MFX_CODEC_HEVC)
+    qsv_dts = gst_qsv_timestamp_to_gst ((mfxU64) bs->DecodeTimeStamp);
 
   if ((bs->FrameType & MFX_FRAMETYPE_IDR) != 0)
     keyframe = TRUE;
@@ -768,10 +779,15 @@ gst_qsv_encoder_finish_frame (GstQsvEncoder * self, GstQsvEncoderTask * task,
     return GST_FLOW_ERROR;
   }
 
-  frame = gst_qsv_encoder_find_output_frame (self, pts);
+  frame = gst_qsv_encoder_find_output_frame (self, qsv_pts);
   if (frame) {
-    frame->pts = pts;
-    frame->dts = dts;
+    if (GST_CLOCK_TIME_IS_VALID (qsv_dts)) {
+      frame->pts = qsv_pts;
+      frame->dts = qsv_dts;
+    } else {
+      frame->dts = frame->pts;
+    }
+
     frame->output_buffer = buffer;
 
     if (keyframe)
@@ -783,8 +799,11 @@ gst_qsv_encoder_finish_frame (GstQsvEncoder * self, GstQsvEncoderTask * task,
   /* Empty available frame, something went wrong but we can just push this
    * buffer */
   GST_WARNING_OBJECT (self, "Failed to find corresponding frame");
-  GST_BUFFER_PTS (buffer) = pts;
-  GST_BUFFER_DTS (buffer) = dts;
+  GST_BUFFER_PTS (buffer) = qsv_pts;
+  if (GST_CLOCK_TIME_IS_VALID (qsv_dts))
+    GST_BUFFER_DTS (buffer) = qsv_dts;
+  else
+    GST_BUFFER_DTS (buffer) = qsv_pts;
 
   if (!keyframe)
     GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT);