Subjective Image Quality Evaluation of Image Compression Techniques

Image compression reduces the amount of data in digital images and, therefore, allows efficient storage, processing, and transmission of pictorial information. However, compression algorithms can degrade image quality by introducing artifacts, which may be unacceptable for users' tasks. This work examined the subjective effects of JPEG and wavelet compression algorithms on a series of medical images. Six digitized chest images were processed by each algorithm at various compression levels. Twelve radiologists rated the perceived image quality of the compressed images relative to the corresponding uncompressed images, as well as rated the acceptability of the compressed images for diagnostic purposes. The results indicate that subjective image quality and acceptability decreased with increasing compression levels; however, all images remained acceptable for diagnostic purposes. At high compression ratios, JPEG compressed images were judged less acceptable for diagnostic purposes than the wavelet compressed images. These results contribute to emerging system design guidelines for digital imaging workstations.

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Design of various Image Compression Methods in Wireless Sensor Networks

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a9851.109119 ◽

2019 ◽

Vol 9 (1) ◽

pp. 2608-2615

Keyword(s):

Image Compression ◽

Matrix Factorization ◽

Least Square ◽

Wireless Sensor ◽

Raspberry Pi ◽

Message Queue ◽

Compression Algorithms ◽

Compressed Images ◽

Non Negative Matrix Factorization

The processing capacity and power of nodes in a Wireless Sensor Network (WSN) are restricted. The quality of the images is deficient, and the contents of the images may vary after decoding when we apply image compression algorithms in WSN. Various compression algorithms are compared in this paper. An Image Compression method based on Restricted Boltzmann Machine (RBM), Auto encoders and Non-negative Matrix Factorization (NMF), Least Square Non-Negative Matrix Factorization (LSNMF), Projective Non-Negative Matrix Factorization (PNMF) network are proposed in this paper. For the WSN, we have used a Message Queue Telemetry Transport (MQTT) protocol. We have used a three Raspberry Pi’s to build a WSN; Publisher, Broker, Subscriber. A Publisher, where it can trigger the camera and captures the images then compress it and send it to another raspberry pi which is a MQTT broker. The PSNR values for those image compression methods were analyzed and compared against each other for images evaluated from the MNIST dataset. Along with the simulation results, all these compression methods are implemented using hardware implementation. Raspberry Pi, a single-board computer with in-built Wi-Fi capabilities, was used in establishing a WSN. Message Queue Telemetry Transport (MQTT) protocol was used for transmitting the compressed images across the WSN, that offers fast and reliable transmission

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Organ doses and subjective image quality of indirect digital panoramic radiography

Dentomaxillofacial Radiology ◽

10.1038/sj.dmfr.4600640 ◽

2001 ◽

Vol 30 (6) ◽

pp. 308-313 ◽

Cited By ~ 8

Author(s):

F Gijbels ◽

G Sanderink ◽

C Bou Serhal ◽

H Pauwels ◽

R Jacobs

Keyword(s):

Image Quality ◽

Panoramic Radiography ◽

Organ Doses ◽

Subjective Image Quality ◽

Digital Panoramic Radiography

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The subjective image quality of direct digital and conventional panoramic radiography

Clinical Oral Investigations ◽

10.1007/s007840000059 ◽

2000 ◽

Vol 4 (3) ◽

pp. 162-167 ◽

Cited By ~ 26

Author(s):

F. Gijbels ◽

A.-M. De Meyer ◽

C. Bou Serhal ◽

C. Van den Bossche ◽

J. Declerck ◽

...

Keyword(s):

Image Quality ◽

Panoramic Radiography ◽

Subjective Image Quality

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The application of the MPEG-4 standard to telepathology images for electronic patient records

Journal of Telemedicine and Telecare ◽

10.1258/135763303322196204 ◽

2003 ◽

Vol 9 (1_suppl) ◽

pp. 19-21 ◽

Cited By ~ 5

Author(s):

Georg A Brox ◽

Janis L Huston

Keyword(s):

Image Quality ◽

Patient Records ◽

Electronic Patient Records ◽

Diagnostic Image ◽

Diagnostic Quality ◽

Compressed Images ◽

Software Packages ◽

Mapping Software ◽

Pixel Mapping

summary We conducted a pilot study to compare the diagnostic quality of digital telepathology images compressed using two software packages, each of which incorporated the MPEG-4 standard. Both software packages produced lossy (rather than lossless) compressed images. Lossy images can be less reliable for diagnostic purposes and the aim of the study was to examine how the MPEG-4 standard affects image quality. The results showed that manipulation of the images by the software did not dramatically alter the image quality but they highlighted the need to develop both pixel-mapping software and associated standards. Standards will help to determine which bits of a diagnostic image can be safely removed during compression while ensuring the integrity and reliability of images for diagnostic purposes.

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Enhanced Three-Dimensional Color Conversion Based on Discrete Wavelet Transform

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.155-156.440 ◽

2012 ◽

Vol 155-156 ◽

pp. 440-444

Author(s):

He Yan ◽

Xiu Feng Wang

Keyword(s):

Information Technology ◽

Wavelet Transform ◽

Image Reconstruction ◽

Image Quality ◽

Image Compression ◽

High Performance ◽

Three Dimensional ◽

Discrete Wavelet ◽

Compression Algorithms ◽

Color Conversion

JPEG2000 algorithm has been developed based on the DWT techniques, which have shown how the results achieved in different areas in information technology can be applied to enhance the performance. Lossy image compression algorithms sacrifice perfect image reconstruction in favor of decreased storage requirements. Wavelets have become a popular technology for information redistribution for high-performance image compression algorithms. Lossy compression algorithms sacrifice perfect image reconstruction in favor of improved compression rates while minimizing image quality lossy.

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Objective and subjective image quality of primary and recurrent squamous cell carcinoma on head and neck low-tube-voltage 80-kVp computed tomography

Neuroradiology ◽

10.1007/s00234-015-1512-x ◽

2015 ◽

Vol 57 (6) ◽

pp. 645-651 ◽

Cited By ~ 18

Author(s):

Jan-Erik Scholtz ◽

Moritz Kaup ◽

Johannes Kraft ◽

Eva-Maria Nöske ◽

Friedrich Scheerer ◽

...

Keyword(s):

Computed Tomography ◽

Squamous Cell Carcinoma ◽

Image Quality ◽

Cell Carcinoma ◽

Head And Neck ◽

Tube Voltage ◽

Subjective Image Quality ◽

Low Tube Voltage ◽

Recurrent Squamous Cell Carcinoma

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A comparative study on image quality of two digital intraoral sensors

Dentomaxillofacial Radiology ◽

10.1259/dmfr.20190063 ◽

2019 ◽

Vol 48 (7) ◽

pp. 20190063 ◽

Cited By ~ 2

Author(s):

Cinar Aziman ◽

Kristina Hellén-Halme ◽

Xie-Qi Shi

Keyword(s):

Image Quality ◽

Observer Agreement ◽

Visual Grading ◽

Intra Class Correlation ◽

Subjective Image Quality ◽

Significant Difference ◽

General Dentists ◽

Parallel Technique ◽

Specialist Group

Objectives The aims of this study were to evaluate the subjective image quality and reliability of two digital sensors. In addition, the image quality of the two sensors evaluated by specialists and general dentists were compared. Methods: 30 intraoral bitewings from five patients were included in the study, 15 were exposed with a Dixi sensor (CCD-based) and 15 with a ProSensor (CMOS-based) using modified parallel technique. Three radiologists and three general dentists evaluated the images in pair. A five-point scale was used to register the image quality. Visual grading characteristics (VGC) analysis was performed to compare the image quality and the observer agreement was assessed in terms of intra class correlation co-efficient. Results No statistically significant difference was found on image quality between the sensors. The average scores of the observer agreement were moderate with an average of 0.66 and an interval of 0.30 to 0.87, suggesting that there was a large variation on preference of image quality. However, there was a statistically significant difference in terms of the area under the VGC- curves between the specialist group and the general dentist group ( p = 0.043), in which the specialist group tended to favor the ProSensor. Conclusions Subjective image quality of the two intraoral sensors were comparable when evaluated by both general and oral radiologists. However, the radiologists seemed to prefer the ProSensor to the Dixi as compared to general dentists. Inter- observer conformance showed a large variation on the preference of the image quality.

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Radiation dose and image quality of high-pitch emergency abdominal CT in obese patients using third-generation dual-source CT (DSCT)

Scientific Reports ◽

10.1038/s41598-019-52454-5 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Robert Forbrig ◽

Michael Ingrisch ◽

Robert Stahl ◽

Katharina Stella Winter ◽

Maximilian Reiser ◽

...

Keyword(s):

Image Quality ◽

Radiation Dose ◽

Third Generation ◽

Obese Patients ◽

Dual Source Ct ◽

High Pitch ◽

Subjective Image Quality ◽

Dual Source ◽

Group A

Abstract In this third-generation dual-source CT (DSCT) study, we retrospectively investigated radiation dose and image quality of portal-venous high-pitch emergency CT in 60 patients (28 female, mean age 56 years) with a body mass index (BMI) ≥ 30 kg/m2. Patients were dichotomized in groups A (median BMI 31.5 kg/m2; n = 33) and B (36.8 kg/m2; n = 27). Volumetric CT dose index (CTDIvol), size-specific dose estimate (SSDE), dose length product (DLP) and effective dose (ED) were assessed. Contrast-to-noise ratio (CNR) and dose-independent figure-of-merit (FOM) CNR were calculated. Subjective image quality was assessed using a five-point scale. Mean values of CTDIvol, SSDE as well as normalized DLP and ED were 7.6 ± 1.8 mGy, 8.0 ± 1.8 mGy, 304 ± 74 mGy * cm and 5.2 ± 1.3 mSv for group A, and 12.6 ± 3.7 mGy, 11.0 ± 2.6 mGy, 521 ± 157 mGy * cm and 8.9 ± 2.7 mSv for group B (p < 0.001). CNR of the liver and spleen as well as each calculated FOM CNR were significantly higher in group A (p < 0.001). Subjective image quality was good in both groups. In conclusion, third-generation abdominal high-pitch emergency DSCT yields good image quality in obese patients. Radiation dose increases in patients with a BMI > 36.8 kg/m2.

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