systemtimer.cc

Linux下比较早的基于命令行的DVD播放器

// Copyright (c) 2004 by Istv醤 V醨adi

// This file is part of dxr3Player, a DVD player written specifically 
// for the DXR3 (aka Hollywood+) decoder card.

// 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, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

//------------------------------------------------------------------------------

#include "SystemTimer.h"

#include "util/Log.h"

//------------------------------------------------------------------------------

using output::SystemTimer;

//------------------------------------------------------------------------------

void SystemTimer::reset()
{
    output::Timer::reset();
    startTime = 0;
}

//------------------------------------------------------------------------------

void SystemTimer::start()
{
    startTime = Util::currentTimeMillis();
}

//------------------------------------------------------------------------------

void SystemTimer::adjustFrequency(pts_t shouldBeSCR)
{
    if (startTime==0) return;

    // FIXME: constants
    millis_t currentTime = Util::currentTimeMillis();
    millis_t millisDiff = currentTime - startTime;
    pts_t currentSCR = millisDiff*scrFrequency/1000000;
    
    if ((currentSCR>(shouldBeSCR+2250) || (currentSCR+2250)<shouldBeSCR)) {
        scrFrequency = shouldBeSCR * 1000000 / millisDiff;
        Log::debug("output::Timer::adjustFrequency: readjusted frequency to %u mHz\n", scrFrequency);
    }
}

//------------------------------------------------------------------------------

pts_t SystemTimer::getCurrentSCR() const
{
    if (startTime==0) return 0;

    millis_t currentTime = Util::currentTimeMillis();
    return (currentTime-startTime)*scrFrequency/1000000;
}

//------------------------------------------------------------------------------

millis_t SystemTimer::getMillis(pts_t scr) const
{
    assert(startTime>0);

    return startTime + scr*1000000/scrFrequency;
}

//------------------------------------------------------------------------------

pts_t SystemTimer::getPTS(millis_t millis) const
{
    assert(startTime>0);
    assert(millis>=startTime);

    return (millis-startTime)*scrFrequency / 1000000;
}

//------------------------------------------------------------------------------

// Local Variables:
// mode: C++
// c-basic-offset: 4
// indent-tabs-mode: nil
// End: