Surface `local_capture_clock_offset` from `RtpSource`
- Propagating `RtpPacketInfo::local_capture_clock_offset`, an
existing field that is related to the abs-capture-timestamp
header extension field `estimated_capture_clock_offset`
- Propagated through `SourceTracker::SourceEntry`
Bug: webrtc:10739, b/246753278
Change-Id: I21d9841e4f3a35da5f8d7b31582898309421d524
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/275241
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38129}
diff --git a/api/BUILD.gn b/api/BUILD.gn
index e9db503..10337cb 100644
--- a/api/BUILD.gn
+++ b/api/BUILD.gn
@@ -94,6 +94,7 @@
":rtp_headers",
":scoped_refptr",
"../rtc_base/system:rtc_export",
+ "units:time_delta",
"units:timestamp",
]
absl_deps = [ "//third_party/abseil-cpp/absl/types:optional" ]
diff --git a/api/rtp_packet_info.h b/api/rtp_packet_info.h
index f9980a1..bc8784c 100644
--- a/api/rtp_packet_info.h
+++ b/api/rtp_packet_info.h
@@ -17,6 +17,7 @@
#include "absl/types/optional.h"
#include "api/rtp_headers.h"
+#include "api/units/time_delta.h"
#include "api/units/timestamp.h"
#include "rtc_base/system/rtc_export.h"
@@ -92,11 +93,11 @@
return *this;
}
- const absl::optional<int64_t>& local_capture_clock_offset() const {
+ const absl::optional<TimeDelta>& local_capture_clock_offset() const {
return local_capture_clock_offset_;
}
RtpPacketInfo& set_local_capture_clock_offset(
- const absl::optional<int64_t>& value) {
+ absl::optional<TimeDelta> value) {
local_capture_clock_offset_ = value;
return *this;
}
@@ -117,16 +118,14 @@
// Fields from the Absolute Capture Time header extension:
// http://www.webrtc.org/experiments/rtp-hdrext/abs-capture-time
- // To not be confused with `local_capture_clock_offset_`, the
- // `estimated_capture_clock_offset` in `absolute_capture_time_` should
- // represent the clock offset between a remote sender and the capturer, and
- // thus equals to the corresponding values in the received RTP packets,
- // subjected to possible interpolations.
absl::optional<AbsoluteCaptureTime> absolute_capture_time_;
- // Clock offset against capturer's clock. Should be derived from the estimated
- // capture clock offset defined in the Absolute Capture Time header extension.
- absl::optional<int64_t> local_capture_clock_offset_;
+ // Clock offset between the local clock and the capturer's clock.
+ // Do not confuse with `AbsoluteCaptureTime::estimated_capture_clock_offset`
+ // which instead represents the clock offset between a remote sender and the
+ // capturer. The following holds:
+ // Capture's NTP Clock = Local NTP Clock + Local-Capture Clock Offset
+ absl::optional<TimeDelta> local_capture_clock_offset_;
};
bool operator==(const RtpPacketInfo& lhs, const RtpPacketInfo& rhs);
diff --git a/api/rtp_packet_info_unittest.cc b/api/rtp_packet_info_unittest.cc
index 80abccc..d35edf7 100644
--- a/api/rtp_packet_info_unittest.cc
+++ b/api/rtp_packet_info_unittest.cc
@@ -9,6 +9,7 @@
*/
#include "api/rtp_packet_infos.h"
+#include "api/units/time_delta.h"
#include "test/gmock.h"
#include "test/gtest.h"
@@ -186,7 +187,7 @@
}
TEST(RtpPacketInfoTest, LocalCaptureClockOffset) {
- constexpr absl::optional<int64_t> kValue = 10;
+ constexpr TimeDelta kValue = TimeDelta::Micros(8868963877546349045LL);
RtpPacketInfo lhs;
RtpPacketInfo rhs;
diff --git a/api/transport/rtp/BUILD.gn b/api/transport/rtp/BUILD.gn
index 26036c7..205bbcc 100644
--- a/api/transport/rtp/BUILD.gn
+++ b/api/transport/rtp/BUILD.gn
@@ -13,6 +13,7 @@
sources = [ "rtp_source.h" ]
deps = [
"../../../api:rtp_headers",
+ "../../../api/units:time_delta",
"../../../rtc_base:checks",
]
absl_deps = [ "//third_party/abseil-cpp/absl/types:optional" ]
diff --git a/api/transport/rtp/rtp_source.h b/api/transport/rtp/rtp_source.h
index c19cfeb..e51dcd7 100644
--- a/api/transport/rtp/rtp_source.h
+++ b/api/transport/rtp/rtp_source.h
@@ -15,6 +15,7 @@
#include "absl/types/optional.h"
#include "api/rtp_headers.h"
+#include "api/units/time_delta.h"
#include "rtc_base/checks.h"
namespace webrtc {
@@ -28,7 +29,17 @@
public:
struct Extensions {
absl::optional<uint8_t> audio_level;
+
+ // Fields from the Absolute Capture Time header extension:
+ // http://www.webrtc.org/experiments/rtp-hdrext/abs-capture-time
absl::optional<AbsoluteCaptureTime> absolute_capture_time;
+
+ // Clock offset between the local clock and the capturer's clock.
+ // Do not confuse with `AbsoluteCaptureTime::estimated_capture_clock_offset`
+ // which instead represents the clock offset between a remote sender and the
+ // capturer. The following holds:
+ // Capture's NTP Clock = Local NTP Clock + Local-Capture Clock Offset
+ absl::optional<TimeDelta> local_capture_clock_offset;
};
RtpSource() = delete;
@@ -74,6 +85,10 @@
return extensions_.absolute_capture_time;
}
+ absl::optional<TimeDelta> local_capture_clock_offset() const {
+ return extensions_.local_capture_clock_offset;
+ }
+
bool operator==(const RtpSource& o) const {
return timestamp_ms_ == o.timestamp_ms() && source_id_ == o.source_id() &&
source_type_ == o.source_type() &&