Palabras clave
alternating projection method
alternating or- thogonal projections
convex projections
parallel subgradient projection
El problem de restauración de imágenes
el método de las proyecciones alternas
proyecciones ortogonales alternantes
proyecciones sobre convexos
proyección por subgradientes en paralelo
Cómo citar
Resumen
Los algoritmos de proyección han evolucionado a partir del algoritmo de proyección alternante propuesto por J. von Neumann en 1933, donde el espacio solución es la intersección de un número finito de subespacios o conjuntos convexos. Investigaciones recientes se han centrado en técnicas para acelerar la convergencia del método y explotar el multiprocesamiento.
n este trabajo consideramos el problema de restauración de imágenes. La mayoría de las técnicas desarrolladas para resolverlo han usado algoritmos iterativos; una de ellas consiste en usar proyecciones ortogonales alternantes.
Llevamos a cabo una revisión cronológica de las diferentes técnicas en las que se ha aplicado el método de las proyecciones ortogonales alternantes al problema de restauración de imágenes, hasta llegar al enfoque reciente de Combettes (1997-1999), en donde la restauración se basa en el cálculo de proyecciones aproximadas, en lugar de proyecciones exactas.
Citas
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