Abstract

When imaging is performed by using a coherent signal, the result is frequently a realization of the stochastic process known as speckle. The information sought from this process is often the mean value of its envelope or intensity at each point in the image plane. When only a single realization of the process is available, ergodicity is required within a sufficiently large region for accurate estimation of the mean. The identification of these regions is the segmentation problem that is addressed. The approach presented clips the speckle image at a constant threshold level and analyzes the resulting bilevel image based on the level-crossing statistics of the speckle process. An analysis of the level-crossing process leads to a decision rule for identifying or segmenting distinct regions of the image based on the sizes of the fades and the excursions in the clipped speckle. The measurement of these sizes is accomplished by using the morphological transformations of opening and closing. This new approach has been applied to computer-generated speckle images and may prove useful in laser, ultrasound, and radar imaging, in which speckle phenomena are manifest.

© 1991 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Mean level signal crossing rate for an arbitrary stochastic process

Harold T. Yura and Steen G. Hanson
J. Opt. Soc. Am. A 27(4) 797-807 (2010)

Detection of phase in modulated optical signals subject to ideal Rayleigh fading

Riho Terras
J. Opt. Soc. Am. A 3(11) 1816-1825 (1986)

Mean level signal crossing rate for an arbitrary stochastic process: reply to comment

Harold T. Yura and Steen G. Hanson
J. Opt. Soc. Am. A 29(2) 167-168 (2012)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (10)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (4)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (44)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription