mediapipe/mediapipe/calculators/util/clock_latency_calculator.cc
MediaPipe Team b133b0f200 Project import generated by Copybara.
GitOrigin-RevId: afeb9cf5a8c069c0a566d16e1622bbb086170e4d
2020-05-21 13:37:51 -04:00

117 lines
4.0 KiB
C++

// Copyright 2020 The MediaPipe Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "absl/time/time.h"
#include "mediapipe/framework/calculator_framework.h"
#include "mediapipe/framework/port/logging.h"
#include "mediapipe/framework/port/ret_check.h"
#include "mediapipe/framework/port/status.h"
namespace mediapipe {
namespace {
// Tag name for reference signal.
constexpr char kReferenceTag[] = "REFERENCE";
} // namespace
// A calculator that diffs multiple input absl::Time streams against a
// reference Time stream, and outputs the resulting absl::Duration's. Useful
// in combination with ClockTimestampCalculator to be able to determine the
// latency between two different points in a graph.
//
// Inputs: At least one non-reference Time stream is required.
// 0- Time stream 0
// 1- Time stream 1
// ...
// N- Time stream N
// REFERENCE_SIGNAL (required): The Time stream by which all others are
// compared. Should be the stream from which our other streams were
// computed, in order to provide meaningful latency results.
//
// Outputs:
// 0- Duration from REFERENCE_SIGNAL to input stream 0
// 1- Duration from REFERENCE_SIGNAL to input stream 1
// ...
// N- Duration from REFERENCE_SIGNAL to input stream N
//
// Example config:
// node {
// calculator: "ClockLatencyCalculator"
// input_stream: "packet_clocktime_stream_0"
// input_stream: "packet_clocktime_stream_1"
// input_stream: "packet_clocktime_stream_2"
// input_stream: "REFERENCE_SIGNAL: packet_clocktime_stream_reference"
// output_stream: "packet_latency_stream_0"
// output_stream: "packet_latency_stream_1"
// output_stream: "packet_latency_stream_2"
// }
//
class ClockLatencyCalculator : public CalculatorBase {
public:
ClockLatencyCalculator() {}
static ::mediapipe::Status GetContract(CalculatorContract* cc);
::mediapipe::Status Open(CalculatorContext* cc) override;
::mediapipe::Status Process(CalculatorContext* cc) override;
private:
int64 num_packet_streams_ = -1;
};
REGISTER_CALCULATOR(ClockLatencyCalculator);
::mediapipe::Status ClockLatencyCalculator::GetContract(
CalculatorContract* cc) {
RET_CHECK_GT(cc->Inputs().NumEntries(), 1);
int64 num_packet_streams = cc->Inputs().NumEntries() - 1;
RET_CHECK_EQ(cc->Outputs().NumEntries(), num_packet_streams);
for (int64 i = 0; i < num_packet_streams; ++i) {
cc->Inputs().Index(i).Set<absl::Time>();
cc->Outputs().Index(i).Set<absl::Duration>();
}
cc->Inputs().Tag(kReferenceTag).Set<absl::Time>();
return ::mediapipe::OkStatus();
}
::mediapipe::Status ClockLatencyCalculator::Open(CalculatorContext* cc) {
// Direct passthrough, as far as timestamp and bounds are concerned.
cc->SetOffset(TimestampDiff(0));
num_packet_streams_ = cc->Inputs().NumEntries() - 1;
return ::mediapipe::OkStatus();
}
::mediapipe::Status ClockLatencyCalculator::Process(CalculatorContext* cc) {
// Get reference time.
RET_CHECK(!cc->Inputs().Tag(kReferenceTag).IsEmpty());
const absl::Time& reference_time =
cc->Inputs().Tag(kReferenceTag).Get<absl::Time>();
// Push Duration packets for every input stream we have.
for (int64 i = 0; i < num_packet_streams_; ++i) {
if (!cc->Inputs().Index(i).IsEmpty()) {
const absl::Time& input_stream_time =
cc->Inputs().Index(i).Get<absl::Time>();
cc->Outputs().Index(i).AddPacket(
MakePacket<absl::Duration>(input_stream_time - reference_time)
.At(cc->InputTimestamp()));
}
}
return ::mediapipe::OkStatus();
}
} // namespace mediapipe