Ribera - Revision history

imported>Student221: forgot to attach final presentation slides

2019-12-16T17:54:03Z

forgot to attach final presentation slides

← Older revision		Revision as of 17:54, 16 December 2019
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	Our porposed method is able to incoporate OTFs from multiple sources.		Our porposed method is able to incoporate OTFs from multiple sources.
	We expect this method to be a useful tool to design future Virtual Reality headsets.		We expect this method to be a useful tool to design future Virtual Reality headsets.

			== Files ==
			[http://scarlet.stanford.edu/teach/images/8/86/Slides_20191210_psych221.zip Presentation slides]

	== References ==		== References ==

imported>Student221: /* Methods */

2019-12-16T06:44:00Z

Methods

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	[[File:OTFmodelsTable.PNG\|800px\|thumb\|center\|Table 1. Critical characteristics of a few OTF models.]]		[[File:OTFmodelsTable.PNG\|800px\|thumb\|center\|Table 1. Critical characteristics of a few OTF models.]]

	One can note in recent works (~~bla~~ and ~~bla~~) the higher granularity of the measurements and that they did not did to paralyze accommodation to take the measurements.		One can note in recent works (Jaeken [6] and Polans [7]) the higher granularity of the measurements and that they did not did to paralyze accommodation to take the measurements.
	This is because of the use of more modern instrumentation that can operate much faster.		This is because of the use of more modern instrumentation that can operate much faster.
	Also one could make use of the ISO12233 standard to measure the MTF of the HVS ourselves, and incorporate for example the effect of the subsampling and demosaicking of the cones in the retina.		Also one could make use of the ISO12233 standard to measure the MTF of the HVS ourselves, and incorporate for example the effect of the subsampling and demosaicking of the cones in the retina.

imported>Student221: /* Background */

2019-12-16T06:43:24Z

Background

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	[[File:Isetbiolab_pictorial.png\|400px\|thumb\|center\|Figure 2. Example of an image going through ISETBIOLAB]]		[[File:Isetbiolab_pictorial.png\|400px\|thumb\|center\|Figure 2. Example of an image going through ISETBIOLAB]]

	On the other hand, the Optical Transfer Function (OTF) of the HVS has been measured in a variety of ways, including double-pass interferomic measurements [4, 5] and wavefront sensors [6].		On the other hand, the Optical Transfer Function (OTF) of the HVS has been measured in a variety of ways, including double-pass interferomic measurements [4, 5] and wavefront sensors [6, 7].
	These OTFs depend on the eccentricity of the incoming rays crossing the human pupil, thus applying an OTF obtained from an on-axis analysis to an image observed with a wide field of view is not correct.		These OTFs depend on the eccentricity of the incoming rays crossing the human pupil, thus applying an OTF obtained from an on-axis analysis to an image observed with a wide field of view is not correct.

imported>Student221: /* References */

2019-12-16T06:43:01Z

References

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	[6] B. Jaeken and P. Artal, "Optical Quality of Emmetropic and Myopic Eyes in the Periphery Measured with High-Angular Resolution," Journal of Visual Psychophysics and Physiological Optics, vol. 53, no. 7, June 2012. https://doi.org/10.1167/iovs.11-8993		[6] B. Jaeken and P. Artal, "Optical Quality of Emmetropic and Myopic Eyes in the Periphery Measured with High-Angular Resolution," Journal of Visual Psychophysics and Physiological Optics, vol. 53, no. 7, June 2012. https://doi.org/10.1167/iovs.11-8993

			[7] J. Polans, B. Jaeken, R. P. McNabb, P. Artal, and J. A. Izatt "Wide-field optical model of the human eye with asymmetrically tilted and decentered lens that reproduces measured ocular aberrations," Optica, vol. 2, no. 2, pp. 124-134, 2015. https://doi.org/10.1364/OPTICA.2.000124

imported>Student221: /* References */

2019-12-16T06:37:59Z

References

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	[2] G. W. Cook, J. Ribera, D. Stolitzka and W. Xiong, "A Subpixel‐based Objective Image Quality Metric with Application to Visually Lossless Image Compression Evaluation," Society for Information Display Digest of Technical Papers, vol. 49, no. 1, May 2018. https://doi.org/10.1002/sdtp.12103		[2] G. W. Cook, J. Ribera, D. Stolitzka and W. Xiong, "A Subpixel‐based Objective Image Quality Metric with Application to Visually Lossless Image Compression Evaluation," Society for Information Display Digest of Technical Papers, vol. 49, no. 1, May 2018. https://doi.org/10.1002/sdtp.12103

	[3] https://github.com/isetbio/isetbio		[3] https://github.com/isetbio/isetbio

imported>Student221: /* Conclusions */

2019-12-14T06:15:45Z

Conclusions

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	In this project we have proposed and implemented a procedure to extend an image quality metric for high field of view viewing conditions.		In this project we have proposed and implemented a procedure to extend an image quality metric for high field of view viewing conditions.
	We have used an image quality metric that follows the computational observer approach of ISETBio, and simulates the physics of every step in the pipeline of the Human Visual System.		We have used an image quality metric that follows the computational observer approach of ISETBio, and simulates the physics of every step in the pipeline of the Human Visual System.
	Our porposed method ~~incor~~		Our porposed method is able to incoporate OTFs from multiple sources.
			We expect this method to be a useful tool to design future Virtual Reality headsets.

	== References ==		== References ==

imported>Student221: /* Limtiations of the model and future work */

2019-12-14T06:13:27Z

Limtiations of the model and future work

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	== Limtiations of the model and future work ==		== Limtiations of the model and future work ==
	The most important limitation of this model is the computationally ~~efficiency~~		The most important limitation of this model is the computationally inefficiency
	Furthermore, the method approximates the radial increase of eccentricity with step functions.		Furthermore, the method approximates the radial increase of eccentricity with step functions.
	This makes		This makes it innaccurate unless the number of steps is very high.
			Increasing the number of steps makes the method increasingly wasteful of computational resources.
			Another limitation is the fact that the Jaeken model was not measured using a light in the visible spectrums.
			However this is a limitation of the OTF mode and not the eccentricity-variant pipeline.
			We expect such OTF can be extended to other wavelengths.

	== Conclusions ==		== Conclusions ==

imported>Student221: /* Conclusions */

2019-12-13T05:14:04Z

Conclusions

← Older revision		Revision as of 05:14, 13 December 2019
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	All the Delta E error maps shown in this report are using the jet colormap, linearly scaled between 0 and 8.		All the Delta E error maps shown in this report are using the jet colormap, linearly scaled between 0 and 8.
	Any Delta E value above 8 has been clipped to 8.		Any Delta E value above 8 has been clipped to 8.

			== Limtiations of the model and future work ==
			The most important limitation of this model is the computationally efficiency
			Furthermore, the method approximates the radial increase of eccentricity with step functions.
			This makes

	== Conclusions ==		== Conclusions ==
	In this project we have proposed and implemented a procedure to extend an image quality metric for high field of view viewing conditions. ~~Future work includes ..~~.		In this project we have proposed and implemented a procedure to extend an image quality metric for high field of view viewing conditions.
			We have used an image quality metric that follows the computational observer approach of ISETBio, and simulates the physics of every step in the pipeline of the Human Visual System.
			Our porposed method incor

	== References ==		== References ==

imported>Student221: /* Results */

2019-12-13T05:10:40Z

Results

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	The reconstructed image has been compressed and decompressed using JPEG with a relatively low Quality Factor.		The reconstructed image has been compressed and decompressed using JPEG with a relatively low Quality Factor.
	The original image has been obtained from Wikimedia [[https://commons.wikimedia.org/wiki/File:Female_Striped_Horse_Fly_(Tabanus_lineola).png]].		The original image has been obtained from Wikimedia [[https://commons.wikimedia.org/wiki/File:Female_Striped_Horse_Fly_(Tabanus_lineola).png]].
	From the following link: http://scarlet.stanford.edu/teach/images/3/30/Flickering_fly_errormap.gif you can the error map obtained via the proposed eccentricity-dependent ISETBIOLAB, flickering at 10Hz with the traditional on-axis ISETBIOLAB.		From the following link: http://scarlet.stanford.edu/teach/images/3/30/Flickering_fly_errormap.gif , you can see the error map obtained via the proposed eccentricity-dependent ISETBIOLAB, flickering at 10Hz with the traditional on-axis ISETBIOLAB.
	Note that, except for the central circular region, the Delta E values are higher than in the traditional on-axis ISETBIOLAB.		Note that, except for the central circular region, the Delta E values are higher than in the traditional on-axis ISETBIOLAB.
	This effect increases as the eccentricity increases, as expected, suggesting a progressive decrease in the ability to discern compression artifacts as the eccentricity increases.		This effect increases as the eccentricity increases, as expected, suggesting a progressive decrease in the ability to discern compression artifacts as the eccentricity increases.

imported>Student221 at 05:10, 13 December 2019

2019-12-13T05:10:18Z

← Older revision		Revision as of 05:10, 13 December 2019
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	Note that, except for the central circular region, the Delta E values are higher than in the traditional on-axis ISETBIOLAB.		Note that, except for the central circular region, the Delta E values are higher than in the traditional on-axis ISETBIOLAB.
	This effect increases as the eccentricity increases, as expected, suggesting a progressive decrease in the ability to discern compression artifacts as the eccentricity increases.		This effect increases as the eccentricity increases, as expected, suggesting a progressive decrease in the ability to discern compression artifacts as the eccentricity increases.

			All the Delta E error maps shown in this report are using the jet colormap, linearly scaled between 0 and 8.
			Any Delta E value above 8 has been clipped to 8.

	== Conclusions ==		== Conclusions ==