Abstract：
:A contrast-detail (CD) experiment was performed to study the effect of lossy compression on computed radiographic (CR) images. Digital CR images of a phantom were compressed by quantizing the full-frame discrete cosine transform and Huffman encoding the result. Since low-contrast detectability is directly linked to an important radiological task, namely, the detection of noncalcified pulmonary nodules in adult chest radiographs, the goal of the study was to quantify any loss in low-contrast detectability due to compression. Compression ratios varied significantly among compressed images, despite the use of fixed compression parameters; detectability could be specified by a single parameter of a CD curve; there was no significant reduction in detectability for an average compression ratio of 11:1; and, there was a statistically significant degradation in detectability for an average compression ratio of 125:1.
journal_name
Med Physjournal_title
Medical physicsauthors
Cook LT,Insana MF,McFadden MA,Hall TJ,Cox GGdoi
10.1118/1.597489subject
Has Abstractpub_date
1995-06-01 00:00:00pages
715-21issue
6eissn
0094-2405issn
2473-4209journal_volume
22pub_type
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