/* Copyright 2016, Ableton AG, Berlin. All rights reserved.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*
* If you would like to incorporate Link into a proprietary software application,
* please contact .
*/
#pragma once
#include
#include
#include
#include
#include
namespace ableton
{
namespace link
{
template
class BasicHostTimeFilter
{
using Points = std::vector>;
using PointIt = typename Points::iterator;
public:
BasicHostTimeFilter()
: mIndex(0)
{
mPoints.reserve(kNumPoints);
}
~BasicHostTimeFilter() = default;
void reset()
{
mIndex = 0;
mPoints.clear();
}
std::chrono::microseconds sampleTimeToHostTime(const NumberType sampleTime)
{
const auto micros = static_cast(mHostTimeSampler.micros().count());
const auto point = std::make_pair(sampleTime, micros);
if (mPoints.size() < kNumPoints)
{
mPoints.push_back(point);
}
else
{
mPoints[mIndex] = point;
}
mIndex = (mIndex + 1) % kNumPoints;
const auto result = linearRegression(mPoints.begin(), mPoints.end());
const auto hostTime = (result.first * sampleTime) + result.second;
return std::chrono::microseconds(llround(hostTime));
}
private:
std::size_t mIndex;
Points mPoints;
Clock mHostTimeSampler;
};
template
using HostTimeFilter = BasicHostTimeFilter;
} // namespace link
} // namespace ableton