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Updated: Jun 26, 2026
09:55
Troubleshooting and Quality Assurance in Hyperpolarized Xenon Magnetic Resonance Imaging: Tools for High-Quality Image Acquisition
Published on: January 5, 2024
Subjective evaluation of spatial resolution and quantization noise tradeoffs.
Soo Hyun Bae1, Thrasyvoulos N Pappas, Biing-Hwang Juang
1Center for Signal and Image Processing, Georgia Institute of Technology, Atlanta, GA 30332-0250, USA. soohyun@ece.gatech.edu
Summary
Image quality perception is complex. Observers prefer lower resolution to reduce compression artifacts, accepting more artifacts as image size decreases, informing new image quality metrics.
Area of Science:
- Image processing and visual perception
- Digital signal compression
- Human-computer interaction
Background:
- Traditional image quality metrics assume fixed viewing conditions and resolution.
- Adaptive viewing conditions (distance, resolution) are crucial for optimizing perceived quality in applications like video streaming.
- Compression artifacts can be mitigated by adjusting resolution or viewing distance.
Purpose of the Study:
- To investigate the tradeoff between image resolution, viewing conditions, and perceived compression artifact visibility.
- To understand observer preferences for image quality under varying compression levels and display sizes.
- To provide data for developing novel image quality assessment metrics accounting for viewing conditions.
Main Methods:
- Conducted subjective tests with participants evaluating still images compressed using JPEG and JPEG 2000 codecs.
- Varied spatial resolution and implicitly, viewing conditions to assess perceived image quality.
- Analyzed observer preferences regarding compression artifact visibility and image size.
Main Results:
- Observers preferred reduced spatial resolution to minimize compression artifact visibility, but not to the point of invisibility.
- Willingness to tolerate compression artifacts increased as image size decreased.
- Subjective test results provide insights into optimal viewing conditions for compressed images.
Conclusions:
- Image quality perception is influenced by a complex interplay of compression, resolution, and viewing conditions.
- Findings support the development of new image fidelity metrics that incorporate adaptive viewing parameters.
- The study's insights, focused on still images, are expected to extend to video quality assessment.
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