1 files changed, 124 insertions, 0 deletions
diff --git a/webrtc/modules/video_coding/content_metrics_processing.cc b/webrtc/modules/video_coding/content_metrics_processing.cc
new file mode 100644
index 0000000000..0c3a6dbc6c
--- /dev/null
+++ b/webrtc/modules/video_coding/content_metrics_processing.cc
@@ -0,0 +1,124 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/modules/video_coding/content_metrics_processing.h"
+
+#include <math.h>
+
+#include "webrtc/modules/include/module_common_types.h"
+#include "webrtc/modules/video_coding/include/video_coding_defines.h"
+
+namespace webrtc {
+//////////////////////////////////
+/// VCMContentMetricsProcessing //
+//////////////////////////////////
+
+VCMContentMetricsProcessing::VCMContentMetricsProcessing()
+    : recursive_avg_factor_(1 / 150.0f),  // matched to  30fps.
+      frame_cnt_uniform_avg_(0),
+      avg_motion_level_(0.0f),
+      avg_spatial_level_(0.0f) {
+  recursive_avg_ = new VideoContentMetrics();
+  uniform_avg_ = new VideoContentMetrics();
+}
+
+VCMContentMetricsProcessing::~VCMContentMetricsProcessing() {
+  delete recursive_avg_;
+  delete uniform_avg_;
+}
+
+int VCMContentMetricsProcessing::Reset() {
+  recursive_avg_->Reset();
+  uniform_avg_->Reset();
+  frame_cnt_uniform_avg_ = 0;
+  avg_motion_level_ = 0.0f;
+  avg_spatial_level_ = 0.0f;
+  return VCM_OK;
+}
+
+void VCMContentMetricsProcessing::UpdateFrameRate(uint32_t frameRate) {
+  // Update factor for recursive averaging.
+  recursive_avg_factor_ = static_cast<float>(1000.0f) /
+                          static_cast<float>(frameRate * kQmMinIntervalMs);
+}
+
+VideoContentMetrics* VCMContentMetricsProcessing::LongTermAvgData() {
+  return recursive_avg_;
+}
+
+VideoContentMetrics* VCMContentMetricsProcessing::ShortTermAvgData() {
+  if (frame_cnt_uniform_avg_ == 0) {
+    return NULL;
+  }
+  // Two metrics are used: motion and spatial level.
+  uniform_avg_->motion_magnitude =
+      avg_motion_level_ / static_cast<float>(frame_cnt_uniform_avg_);
+  uniform_avg_->spatial_pred_err =
+      avg_spatial_level_ / static_cast<float>(frame_cnt_uniform_avg_);
+  return uniform_avg_;
+}
+
+void VCMContentMetricsProcessing::ResetShortTermAvgData() {
+  // Reset.
+  avg_motion_level_ = 0.0f;
+  avg_spatial_level_ = 0.0f;
+  frame_cnt_uniform_avg_ = 0;
+}
+
+int VCMContentMetricsProcessing::UpdateContentData(
+    const VideoContentMetrics* contentMetrics) {
+  if (contentMetrics == NULL) {
+    return VCM_OK;
+  }
+  return ProcessContent(contentMetrics);
+}
+
+int VCMContentMetricsProcessing::ProcessContent(
+    const VideoContentMetrics* contentMetrics) {
+  // Update the recursive averaged metrics: average is over longer window
+  // of time: over QmMinIntervalMs ms.
+  UpdateRecursiveAvg(contentMetrics);
+  // Update the uniform averaged metrics: average is over shorter window
+  // of time: based on ~RTCP reports.
+  UpdateUniformAvg(contentMetrics);
+  return VCM_OK;
+}
+
+void VCMContentMetricsProcessing::UpdateUniformAvg(
+    const VideoContentMetrics* contentMetrics) {
+  // Update frame counter.
+  frame_cnt_uniform_avg_ += 1;
+  // Update averaged metrics: motion and spatial level are used.
+  avg_motion_level_ += contentMetrics->motion_magnitude;
+  avg_spatial_level_ += contentMetrics->spatial_pred_err;
+  return;
+}
+
+void VCMContentMetricsProcessing::UpdateRecursiveAvg(
+    const VideoContentMetrics* contentMetrics) {
+  // Spatial metrics: 2x2, 1x2(H), 2x1(V).
+  recursive_avg_->spatial_pred_err =
+      (1 - recursive_avg_factor_) * recursive_avg_->spatial_pred_err +
+      recursive_avg_factor_ * contentMetrics->spatial_pred_err;
+
+  recursive_avg_->spatial_pred_err_h =
+      (1 - recursive_avg_factor_) * recursive_avg_->spatial_pred_err_h +
+      recursive_avg_factor_ * contentMetrics->spatial_pred_err_h;
+
+  recursive_avg_->spatial_pred_err_v =
+      (1 - recursive_avg_factor_) * recursive_avg_->spatial_pred_err_v +
+      recursive_avg_factor_ * contentMetrics->spatial_pred_err_v;
+
+  // Motion metric: Derived from NFD (normalized frame difference).
+  recursive_avg_->motion_magnitude =
+      (1 - recursive_avg_factor_) * recursive_avg_->motion_magnitude +
+      recursive_avg_factor_ * contentMetrics->motion_magnitude;
+}
+}  // namespace webrtc