Implement timestamp translation/filter in VideoCapturer.
Use in AndroidVideoCapturer.
BUG=webrtc:5740
Review-Url: https://codereview.webrtc.org/2017443003
Cr-Commit-Position: refs/heads/master@{#13254}
diff --git a/webrtc/base/timestampaligner.h b/webrtc/base/timestampaligner.h
new file mode 100644
index 0000000..35008d3
--- /dev/null
+++ b/webrtc/base/timestampaligner.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2016 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.
+ */
+
+#ifndef WEBRTC_BASE_TIMESTAMPALIGNER_H_
+#define WEBRTC_BASE_TIMESTAMPALIGNER_H_
+
+#include "webrtc/base/basictypes.h"
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/optional.h"
+
+namespace rtc {
+
+class TimestampAligner {
+ public:
+ TimestampAligner();
+ ~TimestampAligner();
+
+ public:
+ // Update the estimated offset between camera time and system monotonic time.
+ int64_t UpdateOffset(int64_t camera_time_us, int64_t system_time_us);
+
+ int64_t ClipTimestamp(int64_t filtered_time_us, int64_t system_time_us);
+
+ private:
+ // State for the timestamp translation.
+ int frames_seen_;
+ // Estimated offset between camera time and system monotonic time.
+ int64_t offset_us_;
+
+ // State for timestamp clipping, applied after the filter, to ensure
+ // that translated timestamps are monotonic and not in the future.
+ // Subtracted from the translated timestamps.
+ int64_t clip_bias_us_;
+ rtc::Optional<int64_t> prev_translated_time_us_;
+ RTC_DISALLOW_COPY_AND_ASSIGN(TimestampAligner);
+};
+
+} // namespace rtc
+
+#endif // WEBRTC_BASE_TIMESTAMPALIGNER_H_