tomwalters@116: /*! tomwalters@116: * \file tomwalters@116: * \brief General definition for frequency scale management tomwalters@116: * tomwalters@116: * \author Willem van Engen tomwalters@116: * \date created 2006/09/26 tomwalters@116: * \version \$Id: Scale.h 576 2008-05-29 12:51:16Z tom $ tomwalters@116: */ tomwalters@116: /* (c) 2006, University of Cambridge, Medical Research Council tomwalters@116: * http://www.pdn.cam.ac.uk/groups/cnbh/aimmanual tomwalters@116: */ tomwalters@116: #ifndef __MODULE_SCALE_H__ tomwalters@116: #define __MODULE_SCALE_H__ tomwalters@116: tom@119: namespace aimc { tomwalters@116: tomwalters@116: /*! tomwalters@116: * \class Scale "Modules/Scale/Scale.h" tomwalters@116: * \brief General class for frequency scale management tomwalters@116: * tomwalters@116: * This class tomwalters@116: * - Converts between a linear and specified scale tomwalters@116: * - Creates filterbank signals based on that scale tomwalters@116: * - Creates any of the children filterbanks with Scale::Create. tomwalters@116: * To create a new scale, all you need to do is override ToLinear() and tomwalters@116: * FromLinear(). See existing scales like ScaleERB for example: tomwalters@116: */ tomwalters@116: class Scale; tomwalters@116: class Scale { tomwalters@116: public: tomwalters@117: //! \brief A list of possible scales tomwalters@117: enum ScaleType { tomwalters@117: SCALE_LINEAR, SCALE_ERB, SCALE_LOG, SCALE_LOGSCALED tomwalters@117: }; tomwalters@117: /*! \brief Create a new scale based on type tomwalters@117: * \param iType Scale type to create tomwalters@117: * \param min Bottom frequency tomwalters@117: * \param max Top frequency tomwalters@117: * \param density Density of distribution on the scale (scale-dependent) tomwalters@117: * \return Newly created scale, to be freed by the caller. tomwalters@117: * tomwalters@117: * This is on purpose no virtual function, always use it Scale::Create(). tomwalters@117: * \todo Split into scaling and filterbank creation parts. tomwalters@117: * Maybe even a separate ScaleMaker that implements Create(). tomwalters@117: */ tomwalters@117: static Scale *Create(ScaleType iType, unsigned int min, unsigned int max, float density); tomwalters@116: tomwalters@117: /*! \overload tomwalters@117: * This function is for scaling-only Scales, you must not create a SignalBank tomwalters@116: * with the returned Scale. tomwalters@117: */ tomwalters@117: static Scale *Create(ScaleType iType); tomwalters@116: tomwalters@117: /*! \brief Create a new Scale tomwalters@117: * \param min Bottom frequency tomwalters@117: * \param max Top frequency tomwalters@117: * \param density Density of distribution on the scale (scale-dependent) tomwalters@117: */ tomwalters@117: Scale(unsigned int min, unsigned int max, float density) { tomwalters@117: m_iMin = min; tomwalters@117: m_iMax = max; tomwalters@117: m_fDensity = density; tomwalters@117: m_sName = NULL; tomwalters@117: }; tomwalters@116: tomwalters@117: virtual ~Scale() { }; tomwalters@116: tomwalters@117: /*! \brief Create an exact copy of this Scale tomwalters@117: * \return A newly created Scale, to be freed by the caller. tomwalters@117: */ tomwalters@117: virtual Scale *Clone(); tomwalters@116: tomwalters@117: //! \return this Signal's ScaleType tomwalters@117: ScaleType getType() { return m_iType; }; tomwalters@117: //! \return this Signal's name tomwalters@117: const char *getName() { return m_sName; }; tomwalters@116: tomwalters@117: /*! \brief Scale a frequency from linear to this scale tomwalters@117: * \param fFreq Frequency to scale tomwalters@117: * \return Scaled frequency tomwalters@117: */ tomwalters@117: virtual float FromLinear(float fFreq) = 0; tomwalters@116: tomwalters@117: /*! \brief Scale a frequency from this scale to linear tomwalters@117: * \param fFreq Scaled frequency to scale back tomwalters@117: * \return Linear frequency tomwalters@117: */ tomwalters@117: virtual float ToLinear(float fFreq) = 0; tomwalters@116: tomwalters@117: /*! \brief Scale from [fMin..fMax] to [-0.5..0.5] tomwalters@117: * \param fVal Value to scale, must be within [fMin..fMax] tomwalters@117: * \return Float in [-0.5..0.5] according to this scale tomwalters@117: * \sa FromLinearScaledExtrema tomwalters@117: * tomwalters@117: * This is mainly for displaying any value on a scale and to make sure tomwalters@117: * that it fits in on screen. Don't use this for any real maths! tomwalters@117: * tomwalters@117: * The default implementation assumes that the scale is monotonic, so the tomwalters@117: * FromLinear(fMin) and FromLinear(fMax) are scale's output boundaries. tomwalters@117: * tomwalters@117: * fMin and fMax are set by FromLinearScaledExtrema. Do not use this before tomwalters@117: * calling that. tomwalters@117: */ tomwalters@117: float FromLinearScaled(float fVal); tomwalters@117: /*! \brief Update the FromLinearScaled min/max values tomwalters@117: * \param fMin Minimum value to be input tomwalters@117: * \param fMax Maxmimum value to be input tomwalters@117: * \sa FromLinearScaled tomwalters@117: */ tomwalters@117: void FromLinearScaledExtrema(float fMin, float fMax); tomwalters@117: /*! \overload tomwalters@117: * \brief Copy min/max values from another Scale tomwalters@117: * \param pScale Scale from which to copy min/max values, must not be NULL tomwalters@117: */ tomwalters@117: void FromLinearScaledExtrema(Scale *pScale); tomwalters@116: tomwalters@116: protected: tomwalters@117: //! \brief Bottom frequency tomwalters@117: unsigned int m_iMin; tomwalters@117: //! \brief Top frequency tomwalters@117: unsigned int m_iMax; tomwalters@117: //! \brief Density of distribution on the scale (scale-dependent) tomwalters@117: float m_fDensity; tomwalters@117: //! \brief The type of this scale, used by Clone(); set this in children. tomwalters@117: ScaleType m_iType; tomwalters@117: //! \brief The name of this scale; set this in children. tomwalters@117: const char *m_sName; tomwalters@116: tomwalters@117: /*! \brief Minimum value for scaling as input tomwalters@117: * \sa FromLinearScaled(), FromLinearScaledExtrema() */ tomwalters@117: float m_fMin; tomwalters@117: /*! \brief Maximum value for scaling as input tomwalters@117: * \sa FromLinearScaled(), FromLinearScaledExtrema() */ tomwalters@117: float m_fMax; tomwalters@117: //! \brief Value used in FromLinearScaled tomwalters@117: float m_fScaledCurHalfSum; tomwalters@117: //! \brief Value used in FromLinearScaled tomwalters@117: float m_fScaledCurDiff; tomwalters@116: }; tom@119: } // namespace aimc tomwalters@116: #endif /* __MODULE_SCALE_H__ */