OpenSceneGraph/src/osgPlugins/ffmpeg/FFmpegImageStream.cpp

#include "FFmpegImageStream.hpp"
#include "FFmpegAudioStream.hpp"

#include <OpenThreads/ScopedLock>
#include <osg/Notify>

#include <memory>



namespace osgFFmpeg {



FFmpegImageStream::FFmpegImageStream() :
    m_decoder(0),
    m_commands(0),
    m_frame_published_flag(false)
{
    setOrigin(osg::Image::TOP_LEFT);

    std::auto_ptr<FFmpegDecoder> decoder(new FFmpegDecoder);
    std::auto_ptr<CommandQueue> commands(new CommandQueue);

    m_decoder = decoder.release();
    m_commands = commands.release();
}



FFmpegImageStream::FFmpegImageStream(const FFmpegImageStream & image, const osg::CopyOp & copyop) :
    osg::ImageStream(image, copyop)
{
    // TODO: probably incorrect or incomplete
}



FFmpegImageStream::~FFmpegImageStream()
{
    osg::notify(osg::INFO)<<"Destructing FFmpegImageStream..."<<std::endl;

    quit(true);
    
    osg::notify(osg::INFO)<<"Have done quit"<<std::endl;

    // release athe audio streams to make sure that the decoder doesn't retain any external
    // refences.
    getAudioStreams().clear();

    // destroy the decoder and associated threads
    m_decoder = 0;


    delete m_commands;

    osg::notify(osg::INFO)<<"Destructed FFMpegImageStream."<<std::endl;
}



bool FFmpegImageStream::open(const std::string & filename)
{
    setFileName(filename);

    if (! m_decoder->open(filename))
        return false;

    setImage(
        m_decoder->video_decoder().width(), m_decoder->video_decoder().height(), 1, GL_RGBA, GL_BGRA, GL_UNSIGNED_BYTE,
        const_cast<unsigned char *>(m_decoder->video_decoder().image()), NO_DELETE
    );

    setPixelAspectRatio(m_decoder->video_decoder().pixelAspectRatio());
    
    m_decoder->video_decoder().setUserData(this);
    m_decoder->video_decoder().setPublishCallback(publishNewFrame);
    
    if (m_decoder->audio_decoder().validContext())
    {
        osg::notify(osg::NOTICE)<<"Attaching FFmpegAudioStream"<<std::endl;
    
        getAudioStreams().push_back(new FFmpegAudioStream(m_decoder.get()));
    }

    _status = PAUSED;
    applyLoopingMode();

    start(); // start thread

    return true;
}



void FFmpegImageStream::play()
{
    m_commands->push(CMD_PLAY);

#if 0
    // Wait for at least one frame to be published before returning the call
    OpenThreads::ScopedLock<Mutex> lock(m_mutex);

    while (duration() > 0 && ! m_frame_published_flag)
        m_frame_published_cond.wait(&m_mutex);

#endif
}



void FFmpegImageStream::pause()
{
    m_commands->push(CMD_PAUSE);
}



void FFmpegImageStream::rewind()
{
    m_commands->push(CMD_REWIND);
}



void FFmpegImageStream::quit(bool waitForThreadToExit)
{
    // Stop the packet producer thread
    if (isRunning())
    {
        m_commands->push(CMD_STOP);

        if (waitForThreadToExit)
            join();
    }

    // Close the decoder (i.e. flush the decoder packet queues)
    m_decoder->close(waitForThreadToExit);
}


double FFmpegImageStream::getLength() const
{ 
    return m_decoder->duration(); 
}



double FFmpegImageStream::getFrameRate() const
{ 
    return m_decoder->video_decoder().frameRate(); 
}



bool FFmpegImageStream::isImageTranslucent() const 
{ 
    return m_decoder->video_decoder().alphaChannel(); 
}



void FFmpegImageStream::run()
{
    try
    {
        bool done = false;

        while (! done)
        {
            if (_status == PLAYING)
            {
                bool no_cmd;
                const Command cmd = m_commands->timedPop(no_cmd, 1);

                if (no_cmd)
                {
                    m_decoder->readNextPacket();
                }
                else
                    done = ! handleCommand(cmd);
            }
            else
            {
                done = ! handleCommand(m_commands->pop());
            }
        }
    }

    catch (const std::exception & error)
    {
        osg::notify(osg::WARN) << "FFmpegImageStream::run : " << error.what() << std::endl;
    }

    catch (...)
    {
        osg::notify(osg::WARN) << "FFmpegImageStream::run : unhandled exception" << std::endl;
    }
    
    osg::notify(osg::NOTICE)<<"Finished FFmpegImageStream::run()"<<std::endl;
}



void FFmpegImageStream::applyLoopingMode()
{
    m_decoder->loop(getLoopingMode() == LOOPING);
}



bool FFmpegImageStream::handleCommand(const Command cmd)
{
    switch (cmd)
    {
    case CMD_PLAY:
        cmdPlay();
        return true;

    case CMD_PAUSE:
        cmdPause();
        return true;

    case CMD_REWIND:
        cmdRewind();
        return true;

    case CMD_STOP:
        return false;

    default:
        assert(false);
        return false;
    }
}



void FFmpegImageStream::cmdPlay()
{
    if (_status == PAUSED)
    {
        if (! m_decoder->audio_decoder().isRunning())
            m_decoder->audio_decoder().start();

        if (! m_decoder->video_decoder().isRunning())
            m_decoder->video_decoder().start();
    }

    _status = PLAYING;
}



void FFmpegImageStream::cmdPause()
{
    if (_status == PLAYING)
    {

    }

    _status = PAUSED;
}



void FFmpegImageStream::cmdRewind()
{
    m_decoder->rewind();
}



void FFmpegImageStream::publishNewFrame(const FFmpegDecoderVideo &, void * user_data)
{
    FFmpegImageStream * const this_ = reinterpret_cast<FFmpegImageStream*>(user_data);

#if 1
    this_->setImage(
        this_->m_decoder->video_decoder().width(), this_->m_decoder->video_decoder().height(), 1, GL_RGBA, GL_BGRA, GL_UNSIGNED_BYTE,
        const_cast<unsigned char *>(this_->m_decoder->video_decoder().image()), NO_DELETE
    );
#else
    /** \bug If viewer.realize() hasn't been already called, this doesn't work? */
    this_->dirty();
#endif

    OpenThreads::ScopedLock<Mutex> lock(this_->m_mutex);

    if (! this_->m_frame_published_flag)
    {
        this_->m_frame_published_flag = true;
        this_->m_frame_published_cond.signal();
    }
}



} // namespace osgFFmpeg