|| || || || || || || ||

---

HistogramExtractor.h

Go to the documentation of this file.

#ifndef Impala_Core_VideoSet_HistogramExtractor_h
#define Impala_Core_VideoSet_HistogramExtractor_h

#include "Core/VideoSet/Reporter.h"
#include "Core/Vector/VectorTem.h"
#include "Core/Feature/FeatureTable.h"

namespace Impala
{
namespace Core
{
namespace VideoSet
{

class HistogramExtractor : public Listener
{

protected:

    typedef Vector::VectorTem<Real64> VectorReal64;

public:

    HistogramExtractor(Reporter* reporter, 
        CmdOptions& options, CString featureName, int binCount)
    {
        mReporter = reporter;
        mFeatureName = featureName;
        mBinCount = binCount;
        Feature::FeatureDefinition def(GetFeatureName());
        mHistogramTable = new Feature::FeatureTable(def, 1000, GetBinCount());
    }

    virtual 
    ~HistogramExtractor()
    {
    }

    String
    GetFeatureName() const
    {
        return mFeatureName;
    }

    virtual void
    HandleNewFrame(VideoSet* vs, int fileId, Stream::RgbDataSrc* src)
    {
        if (!src)
        {
            ILOG_ERROR("Not a valid source for fileId " << fileId);
            return;
        }

        Array::Array2dVec3UInt8* im = Array::ArrayCreate<Array::Array2dVec3UInt8>
            (src->FrameWidth(), src->FrameHeight(), 0, 0, src->DataPtr(), true);
        if (!im)
        {
            ILOG_ERROR("Couldn't load image for fileId " << fileId);
            return;
        }

        Quid quid = vs->GetQuidFrame(fileId, src->FrameNr());

        VectorReal64 histogram = ComputeHistogram(im);

        mHistogramTable->Add(quid, histogram);

        delete im;
    }

    virtual void
    HandleDoneFile(VideoSet* vs, int fileId, Stream::RgbDataSrc* src)
    {
        bool binary = true;
        Feature::FeatureDefinition def = mHistogramTable->GetFeatureDefinition();
        String fName = vs->GetFilePathFeatureData("Keyframes", def, fileId,
                                                  false, -1, true, false);
        if (!fName.empty())
            Table::Write(mHistogramTable, fName, vs->GetDatabase(), binary);
        mHistogramTable->SetSize(0);
    }

protected:

    int
    GetBinCount() const
    {
        return mBinCount;
    }

    virtual VectorReal64
    ComputeHistogram(Array::Array2dVec3UInt8* image) = 0;

    template <class T>
    int
    ComputeBin(const T val, const T low, const T high, const int nrBins) const
    {
        const int bin = (nrBins * (val - low)) / (high - low);
        if (bin >= 0 && bin < nrBins)
            return bin;

        if (val == high)
            return nrBins - 1;

        ILOG_WARN("Unexpected value: " << val << 
            " is not in range [" << low << ", " << high << "]");
        return (bin < 0) ? 0 : nrBins-1;
    }

private:

    Reporter*              mReporter;
    String                 mFeatureName;
    int                    mBinCount;
    Feature::FeatureTable* mHistogramTable;

    ILOG_VAR_DECL;
};

ILOG_VAR_INIT(HistogramExtractor, Impala.Core.VideoSet);

} // namespace VideoSet
} // namespace Core
} // namespace Impala

#endif

---