Computer Image Analysis of the Ocular Fundus

Photographic transparencies of the ocular fundus were scanned with an image dissector under computer control. The image is digitized into 400 X 400 points each exhibiting 256 gray level values. During analysis, the computer stores in its buffer only five consecutive lines upon which image processing is performed; only then is the first line projected on the scope and the following line (the sixth in the original image) introduced into the buffer. In this setup, digitization may be manipulated on-line in real time.

Diapositive des okularen Fundus wurden mit einem »image dissector« unter Computerkontrolle untersucht. Das Bild wird in 400 X 400 Punkte mit je 256 Graustufen digitalisiert. Während der Analyse speichert der Computer nur je fünf aufeinander folgende Bildzeilen, auf denen die Bildverarbeitung stattfindet. Erst dann wird die erste Zeile auf dem Bildschirm dargestellt. Darauf wird die folgende Zeile (die sechste des Originalbildes) in den Speicher geladen. Auf diese Weise kann die Digitalisierung on-line und in Echtzeit beeinflußt werden.

Key-Words

Image Processing - Pattern Recognition - Ocular Fundus - Optic Disc

Schlüssel-Wörter

Bildverarbeitung - Mustererkennung - okularer Fundus - optische Platte

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