Ms. Sirui Hu Profile

Sirui Hu

Research Assistant

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 3 February 2014 Paper

JPEG ringing artifact visibility evaluation

Sirui Hu, Zygmunt Pizlo, Jan Allebach

Proceedings Volume 9016, 90160E (2014) https://doi.org/10.1117/12.2048594

KEYWORDS: Visibility, Image compression, Image quality, Edge detection, Image processing, Optical filters, Molybdenum, Image filtering, Psychophysics, Tablets

Read Abstract +

To achieve high perceptual quality of compressed images, many objective image quality metrics for compression artifacts evaluation and reduction have been developed based on characterization of local image features. However, it is the end user who is judging the image quality in various applications, so the validation of how well these metrics predict human perception is important and necessary. In this paper, we present a preliminary psychophysics experiment method to capture human perception of local ringing artifacts in JPEG images with different severity levels. Observers are asked to annotate the compressed image where they perceive artifacts along the edges, directly on the screen using an interactive tablet display. They are asked to catalog the severity of artifacts into one of the three levels: Strong, Medium, and Light. We process the hand-marked data into a ringing visibility edge map showing a ringing severity mean opinion score (MOS) at every edge pixel. The perceptual information captured in this experiment, enables us to study the correlation between human perception and local image features, which is an important step towards the goal of developing a non-reference (NR) objective metric to predict the visibility of JPEG ringing artifacts in alignment with the assessments of human observers.

Proceedings Article | 25 January 2012 Paper

Color-dependent banding characterization and simulation on natural document images

Sirui Hu, Hila Nachlieli, Doron Shaked, Smadar Shiffman, Jan Allebach

Proceedings Volume 8292, 82920W (2012) https://doi.org/10.1117/12.912901

KEYWORDS: Prototyping, CMYK color model, RGB color model, Printing, Signal processing, Curium, Principal component analysis, Modulation, Calibration, Scanners

Read Abstract +

Print defects like banding from a digital press involve not only luminance variation, but also chrominance variation. As digital presses place one color separation at a time, the contrast and spatial pattern of the print defects are color-space dependent. Characterizing the color-dependent features of the banding signal enables us to simulate the banding on natural document images in a more accurate way that matches the characteristics of the banding generation mechanism within the digital press. A framework is described for color-dependent banding characterization including the following steps: printing and scanning uniform patches that sample colorant combinations throughout the input document sRGB color space, extracting banding signals in the CMYK color space of the target device, and modeling the banding features in a perceptually uniform color space. We obtain a full banding features LUT for every color point in the input sRGB space by interpolating banding features extracted from measured color points. The color-dependent banding simulation framework is developed based on the banding features LUT. Using the information contained in this LUT, a single banding prototype signal is modulated in a color-space-dependent fashion that varies spatially across the natural document image. Proper execution of the framework of banding characterization and simulation requires careful calibration of each system component, as well as implementation of a complete color management pipeline.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years