Evaluation of Lossy data compression of chest X-rays: a receiver operating characteristic study.
OBJECTIVE
To evaluate the quality of chest radiographs after 32:1 compression/decompression with different image compression algorithms.


METHODS
Ten digital (Thoravison) radiographs of an anthropomorphic chest phantom with superimposed simulated nodular lesions (NL) and linear reticular lesions (LL) were obtained. Each radiograph was subdivided into 15 fields; they contained the lesions with a probability of 0.5. The radiographs were compressed and decompressed by using JPEG, fractal and wavelet algorithms at a compression rate of 32:1. Five radiologists evaluated the images. Data were analyzed with the receiver operating characteristic (ROC) method (comparison of area under curve).


RESULTS
At 32:1 JPEG or wavelet compression, no statistically significant difference was observed for both NL and LL when compared with the original images. The fractal algorithm performed significantly lower for both NL and LL when compared with the original radiographs.


CONCLUSIONS
The JPEG and wavelet image compression does not result in loss of relevant information for chest x-rays at a compression rate of 32:1.
Department of Diagnostic Radiology, Freiburg University Hospital, Hugstetter Strasse 55, D-79106 Freiburg, Germany. eko@mrs1.ukl.uni-freiburg.de
Elmar
E
Kotter
Arnold
A
Roesner
Jan
J
Torsten Winterer
Nadir
N
Ghanem
Almut
A
Einert
Dieter
D
Jaeger
Peter
P
Uhrmeister
Mathias
M
Langer
D000465:Algorithms; D019540:Area Under Curve; D017709:Fractals; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D012372:ROC Curve; D013902:Radiography, Thoracic; D011873:Radiology Information Systems