Changeset 3685 for trunk/doc/misc

Timestamp:

Apr 8, 2005, 9:51:57 AM (21 years ago)

Author:

Paul Price

Message:

Small changes.

File:

• trunk/doc/misc/imageCombination.tex (modified) (4 diffs)

trunk/doc/misc/imageCombination.tex

@@ -1 @@
-%%% $Id: imageCombination.tex,v 1.1 2004-12-23 01:56:58 price Exp $
+%%% $Id: imageCombination.tex,v 1.2 2005-04-08 19:51:57 price Exp $
 \documentclass[panstarrs]{panstarrs}
 
@@ -185 +185 @@
 coordinate system of the original input image.  Pixels in this
 transformed map that exceed a specified threshold (\code{frac}), and
-for which the local gradient exceeds another specified threshold
+for which the local gradient is less than another specified threshold
 (\code{grad}) are masked as cosmic rays.  The impact of these maskings
 on the combined image is then propagated through the transformation
@@ -215 +215 @@
 We designate our implementation of the above algorithm ``STAC'', for
 Simultaneous Telescope Array Combination.  It is built on top of the
-\PS{} Library (currently \code{psLib} Release 3), making use of its
+\PS{} Library (currently \code{psLib-rel5alpha1}), making use of its
 vectors, arrays, images, polynomial transformations, statistics and
 tracing functionalities.
@@ -229 +229 @@
 
 Given input images with no CRs (according to the first requirement
-above), STAC falsely identifies $580+479+57+483 = 1599$ pixels as CRs
-in the four individual $512\times512$ input images, or 0.15\% of the
-total number of input pixels.  This meets the requirement by almost an
-order of magnitude.  As an aside, the low number of false CRs
-identified in the third image appears to be due to the nearly integral
-pixel shift to the output coordinate system.
+above), STAC falsely identifies $22+109+161+47 = 339$ pixels as CRs in
+the four individual $512\times512$ input images, or 0.03\% of the
+total number of input pixels.  This meets the requirement by over an
+order of magnitude.
 
 Given input images with 2000~CRs (according to the second requirement
-above), STAC identifies $1580+1583+1273+1439 = 5875$ pixels as CRs in
-the four individual $512\times512$ input images, leaving 96 pixels in
+above), STAC identifies $1692+1222+1256+1624 = 5794$ pixels as CRs in
+the four individual $512\times512$ input images, leaving 29 pixels in
 the combined image exceeding 1.5~times the estimated standard
-deviation of the input images, or 0.04\% of the pixels in the output
-image.  This meets the requirement by a factor of 5.
+deviation of the input images, or 0.01\% of the pixels in the output
+image.  This meets the requirement by an order of magnitude.
 
 Since it meets both of the proposed requirements, STAC (modulo the