org.opencv.bioinspired

Class RetinaFastToneMapping

java.lang.Object

org.opencv.core.Algorithm

org.opencv.bioinspired.RetinaFastToneMapping

public class RetinaFastToneMapping
extends Algorithm

a wrapper class which allows the tone mapping algorithm of Meylan&al(2007) to be used with OpenCV. This algorithm is already implemented in thre Retina class (retina::applyFastToneMapping) but used it does not require all the retina model to be allocated. This allows a light memory use for low memory devices (smartphones, etc. As a summary, these are the model properties:

• 2 stages of local luminance adaptation with a different local neighborhood for each.
• first stage models the retina photorecetors local luminance adaptation
• second stage models th ganglion cells local information adaptation
• compared to the initial publication, this class uses spatio-temporal low pass filters instead of spatial only filters. this can help noise robustness and temporal stability for video sequence use cases.

for more information, read to the following papers : Meylan L., Alleysson D., and Susstrunk S., A Model of Retinal Local Adaptation for the Tone Mapping of Color Filter Array Images, Journal of Optical Society of America, A, Vol. 24, N 9, September, 1st, 2007, pp. 2807-2816Benoit A., Caplier A., Durette B., Herault, J., "USING HUMAN VISUAL SYSTEM MODELING FOR BIO-INSPIRED LOW LEVEL IMAGE PROCESSING", Elsevier, Computer Vision and Image Understanding 114 (2010), pp. 758-773, DOI: http://dx.doi.org/10.1016/j.cviu.2010.01.011 regarding spatio-temporal filter and the bigger retina model : Vision: Images, Signals and Neural Networks: Models of Neural Processing in Visual Perception (Progress in Neural Processing),By: Jeanny Herault, ISBN: 9814273686. WAPI (Tower ID): 113266891.

Field Summary

Fields inherited from class org.opencv.core.Algorithm

nativeObj

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	RetinaFastToneMapping(long addr)

Method Summary

Modifier and Type	Method and Description
static RetinaFastToneMapping	__fromPtr__(long addr)
void	applyFastToneMapping(Mat inputImage, Mat outputToneMappedImage) applies a luminance correction (initially High Dynamic Range (HDR) tone mapping) using only the 2 local adaptation stages of the retina parvocellular channel : photoreceptors level and ganlion cells level.
static RetinaFastToneMapping	create(Size inputSize)
protected void	finalize()
void	setup() updates tone mapping behaviors by adjusing the local luminance computation area (default is 1, see reference paper)
void	setup(float photoreceptorsNeighborhoodRadius) updates tone mapping behaviors by adjusing the local luminance computation area
void	setup(float photoreceptorsNeighborhoodRadius, float ganglioncellsNeighborhoodRadius) updates tone mapping behaviors by adjusing the local luminance computation area
void	setup(float photoreceptorsNeighborhoodRadius, float ganglioncellsNeighborhoodRadius, float meanLuminanceModulatorK) updates tone mapping behaviors by adjusing the local luminance computation area

Methods inherited from class org.opencv.core.Algorithm

clear, empty, getDefaultName, getNativeObjAddr, save

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RetinaFastToneMapping

protected RetinaFastToneMapping(long addr)

Method Detail

__fromPtr__

public static RetinaFastToneMapping __fromPtr__(long addr)

applyFastToneMapping

public void applyFastToneMapping(Mat inputImage,
                                 Mat outputToneMappedImage)

applies a luminance correction (initially High Dynamic Range (HDR) tone mapping) using only the 2 local adaptation stages of the retina parvocellular channel : photoreceptors level and ganlion cells level. Spatio temporal filtering is applied but limited to temporal smoothing and eventually high frequencies attenuation. This is a lighter method than the one available using the regular retina::run method. It is then faster but it does not include complete temporal filtering nor retina spectral whitening. Then, it can have a more limited effect on images with a very high dynamic range. This is an adptation of the original still image HDR tone mapping algorithm of David Alleyson, Sabine Susstruck and Laurence Meylan's work, please cite: -> Meylan L., Alleysson D., and Susstrunk S., A Model of Retinal Local Adaptation for the Tone Mapping of Color Filter Array Images, Journal of Optical Society of America, A, Vol. 24, N 9, September, 1st, 2007, pp. 2807-2816

Parameters:

inputImage - the input image to process RGB or gray levels

outputToneMappedImage - the output tone mapped image

setup

public void setup(float photoreceptorsNeighborhoodRadius,
                  float ganglioncellsNeighborhoodRadius,
                  float meanLuminanceModulatorK)

updates tone mapping behaviors by adjusing the local luminance computation area

Parameters:

photoreceptorsNeighborhoodRadius - the first stage local adaptation area

ganglioncellsNeighborhoodRadius - the second stage local adaptation area

meanLuminanceModulatorK - the factor applied to modulate the meanLuminance information (default is 1, see reference paper)

setup

public void setup(float photoreceptorsNeighborhoodRadius,
                  float ganglioncellsNeighborhoodRadius)

updates tone mapping behaviors by adjusing the local luminance computation area

Parameters:

photoreceptorsNeighborhoodRadius - the first stage local adaptation area

ganglioncellsNeighborhoodRadius - the second stage local adaptation area (default is 1, see reference paper)

setup

public void setup(float photoreceptorsNeighborhoodRadius)

updates tone mapping behaviors by adjusing the local luminance computation area

Parameters:

photoreceptorsNeighborhoodRadius - the first stage local adaptation area (default is 1, see reference paper)

setup

public void setup()

updates tone mapping behaviors by adjusing the local luminance computation area (default is 1, see reference paper)

create

public static RetinaFastToneMapping create(Size inputSize)

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Algorithm

Throws:

Throwable