omxvideodec: Implement a property to control the feeding speedratecontrol

2 files changed, 122 insertions, 1 deletions

diff --git a/omx/gstomxvideodec.c b/omx/gstomxvideodec.c
index 19cf4d7..ed7e090 100644
--- a/omx/gstomxvideodec.c
+++ b/omx/gstomxvideodec.c
@@ -43,6 +43,11 @@ buffer_identification_free (BufferIdentification * id)
 }
 
 /* prototypes */
+static void gst_omx_video_dec_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec);
+static void gst_omx_video_dec_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec);
+
 static void gst_omx_video_dec_finalize (GObject * object);
 
 static GstStateChangeReturn
@@ -71,7 +76,8 @@ static OMX_ERRORTYPE gst_omx_video_dec_deallocate_output_buffers (GstOMXVideoDec
 
 enum
 {
-  PROP_0
+  PROP_0,
+  PROP_RATECTRL
 };
 
 /* class initialization */
@@ -95,6 +101,14 @@ gst_omx_video_dec_class_init (GstOMXVideoDecClass * klass)
   GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
   GstVideoDecoderClass *video_decoder_class = GST_VIDEO_DECODER_CLASS (klass);
 
+  gobject_class->set_property = gst_omx_video_dec_set_property;
+  gobject_class->get_property = gst_omx_video_dec_get_property;
+
+  g_object_class_install_property (gobject_class, PROP_RATECTRL,
+      g_param_spec_int ("rate-control", "Rate control",
+          "Number of frames ahead feeded to decoder (0 unlimited)", 0, 1000, 0,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
   gobject_class->finalize = gst_omx_video_dec_finalize;
 
   element_class->change_state =
@@ -123,6 +137,9 @@ gst_omx_video_dec_init (GstOMXVideoDec * self, GstOMXVideoDecClass * klass)
 
   self->drain_lock = g_mutex_new ();
   self->drain_cond = g_cond_new ();
+
+  self->ratectrl_lock = g_mutex_new ();
+  self->ratectrl_cond = g_cond_new ();
 }
 
 static gboolean
@@ -237,6 +254,9 @@ gst_omx_video_dec_finalize (GObject * object)
   g_mutex_free (self->drain_lock);
   g_cond_free (self->drain_cond);
 
+  g_mutex_free (self->ratectrl_lock);
+  g_cond_free (self->ratectrl_cond);
+
   G_OBJECT_CLASS (parent_class)->finalize (object);
 }
 
@@ -270,6 +290,13 @@ gst_omx_video_dec_change_state (GstElement * element, GstStateChange transition)
       self->draining = FALSE;
       g_cond_broadcast (self->drain_cond);
       g_mutex_unlock (self->drain_lock);
+
+      g_mutex_lock (self->ratectrl_lock);
+      self->frames_in_decoding = 0;
+      self->output_started = FALSE;
+      g_cond_broadcast (self->ratectrl_cond);
+      g_mutex_unlock (self->ratectrl_lock);
+
       break;
     default:
       break;
@@ -798,6 +825,8 @@ gst_omx_video_dec_loop (GstOMXVideoDec * self)
         buf->omx_buf->nFlags, buf->omx_buf->nTimeStamp);
 
     GST_VIDEO_DECODER_STREAM_LOCK (self);
+
+
     frame = _find_nearest_frame (self, buf);
 
     is_eos = ! !(buf->omx_buf->nFlags & OMX_BUFFERFLAG_EOS);
@@ -856,6 +885,23 @@ gst_omx_video_dec_loop (GstOMXVideoDec * self)
 
     GST_DEBUG_OBJECT (self, "Read frame from component");
 
+    /* Wakeup the feeder */
+    if (self->ratectrl) {
+      g_mutex_lock (self->ratectrl_lock);
+      if (self->output_started) {
+        self->frames_in_decoding--;
+        self->frames_in_decoding = MAX (0, self->frames_in_decoding);
+        if (is_eos || flow_ret == GST_FLOW_UNEXPECTED) {
+          self->frames_in_decoding = 0;
+          self->output_started = FALSE;
+        }
+        g_cond_broadcast (self->ratectrl_cond);
+      } else {
+        self->output_started = TRUE;
+      }
+      g_mutex_unlock (self->ratectrl_lock);
+    }
+
     if (is_eos || flow_ret == GST_FLOW_UNEXPECTED) {
       g_mutex_lock (self->drain_lock);
       if (self->draining) {
@@ -1023,6 +1069,12 @@ gst_omx_video_dec_stop (GstVideoDecoder * decoder)
   g_cond_broadcast (self->drain_cond);
   g_mutex_unlock (self->drain_lock);
 
+  g_mutex_lock (self->ratectrl_lock);
+  self->frames_in_decoding = 0;
+  self->output_started = FALSE;
+  g_cond_broadcast (self->ratectrl_cond);
+  g_mutex_unlock (self->ratectrl_lock);
+
   gst_omx_component_get_state (self->dec, 5 * GST_SECOND);
 
   gst_buffer_replace (&self->codec_data, NULL);
@@ -1275,6 +1327,12 @@ gst_omx_video_dec_set_format (GstVideoDecoder * decoder,
     gst_pad_stop_task (GST_VIDEO_DECODER_SRC_PAD (decoder));
     GST_VIDEO_DECODER_STREAM_LOCK (self);
 
+    if (self->ratectrl) {
+      /* Reset rate control state */
+      self->frames_in_decoding = 0;
+      self->output_started = FALSE;
+    }
+
     if (klass->cdata.hacks & GST_OMX_HACK_NO_COMPONENT_RECONFIGURE) {
       GST_VIDEO_DECODER_STREAM_UNLOCK (self);
       gst_omx_video_dec_stop (GST_VIDEO_DECODER (self));
@@ -1655,6 +1713,21 @@ gst_omx_video_dec_handle_frame (GstVideoDecoder * decoder,
 
   GST_DEBUG_OBJECT (self, "Passed frame to component");
 
+  /* Control the speed at which decoder is feeded */
+  if (self->ratectrl && self->downstream_flow_ret == GST_FLOW_OK &&
+      self->output_started) {
+    g_mutex_lock (self->ratectrl_lock);
+    if ((self->frames_in_decoding++) >= self->ratectrl) {
+      /* Make sure to release the base class stream lock, otherwise
+       * _loop() can't call _finish_frame() and we might block forever */
+      GST_VIDEO_DECODER_STREAM_UNLOCK (self);
+      /* Wait for a decoded frame or flush */
+      g_cond_wait (self->ratectrl_cond, self->ratectrl_lock);
+      GST_VIDEO_DECODER_STREAM_LOCK (self);
+    }
+    g_mutex_unlock (self->ratectrl_lock);
+  }
+
   return self->downstream_flow_ret;
 
 full_buffer:
@@ -1814,3 +1887,43 @@ gst_omx_video_dec_drain (GstOMXVideoDec * self, gboolean is_eos)
 
   return GST_FLOW_OK;
 }
+
+static void
+gst_omx_video_dec_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstOMXVideoDec *self;
+
+  g_return_if_fail (GST_IS_OMX_VIDEO_DEC (object));
+
+  self = GST_OMX_VIDEO_DEC (object);
+
+  switch (prop_id) {
+    case PROP_RATECTRL:
+      self->ratectrl = g_value_get_int (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_omx_video_dec_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstOMXVideoDec *self;
+
+  g_return_if_fail (GST_IS_OMX_VIDEO_DEC (object));
+
+  self = GST_OMX_VIDEO_DEC (object);
+
+  switch (prop_id) {
+    case PROP_RATECTRL:
+      g_value_set_int (value, self->ratectrl);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
diff --git a/omx/gstomxvideodec.h b/omx/gstomxvideodec.h
index 6ae9453..3079843 100644
--- a/omx/gstomxvideodec.h
+++ b/omx/gstomxvideodec.h
@@ -80,6 +80,14 @@ struct _GstOMXVideoDec
   gboolean eos;
 
   GstFlowReturn downstream_flow_ret;
+  
+  /* Rate control state */
+  gint ratectrl;
+  gint frames_in_decoding;
+  GMutex *ratectrl_lock;
+  GCond *ratectrl_cond;
+  gboolean output_started;
+
 };
 
 struct _GstOMXVideoDecClass