LSSTApplications  19.0.0-14-gb0260a2+64befe7c1c,20.0.0+0b340dd7c4,20.0.0+1540ce6389,20.0.0+7c6b12c2f9,20.0.0+ae956f52c5,20.0.0+be870186d9,20.0.0+e2e26847c2,20.0.0-1-g04bee24+7c6b12c2f9,20.0.0-1-g10df615+fbe45b1aff,20.0.0-1-g253301a+7c6b12c2f9,20.0.0-1-g2b7511a+46a6078777,20.0.0-1-g4d801e7+9d50d6c21a,20.0.0-1-g5b95a8c+8ebfc75efb,20.0.0-1-gb058bd0+46a6078777,20.0.0-1-gb88604f+acecce4127,20.0.0-1-gc96f8cb+016e330d09,20.0.0-1-gedffbd8+83814edeba,20.0.0-10-g0891cd99+a5f14e9acb,20.0.0-10-g9a20bd332+576ca7b471,20.0.0-17-gcdbda88+0e26bfb1e6,20.0.0-2-g4dae9ad+016e330d09,20.0.0-2-g61b8584+85c46248f3,20.0.0-2-gb780d76+f45b7d88f4,20.0.0-21-g9bbb7f7+016e330d09,20.0.0-22-gc512666+f30f3883a7,20.0.0-23-g8900aa8+68630f7098,20.0.0-3-g1653f94+85c46248f3,20.0.0-3-g4cc78c6+63636aeed8,20.0.0-3-g750bffe+e05f822de9,20.0.0-3-gbd60e8c+ff10c6d78d,20.0.0-32-g15a0e07c+a4c9d0309b,20.0.0-4-g97dc21a+68630f7098,20.0.0-4-gfea843c+f45b7d88f4,20.0.0-5-g357b56b+f45b7d88f4,20.0.0-6-g9a5b7a1+b0f8c2be93,20.0.0-60-gad89340+e4dd172200,20.0.0-7-gcda7bf1+673816f70c,w.2020.43
LSSTDataManagementBasePackage
image1.cc
/*
* LSST Data Management System
* Copyright 2008, 2009, 2010 LSST Corporation.
*
* This product includes software developed by the
* LSST Project (http://www.lsst.org/).
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the LSST License Statement and
* the GNU General Public License along with this program. If not,
* see <http://www.lsstcorp.org/LegalNotices/>.
*/
/*
* Image iterator tutorial.
*/
// Include the necessary headers;
// if using many image modules then you may prefer to include "lsst/afw/image.h"
#include "lsst/geom.h"
// Declare the desired Image type.
// Note: only specific types are supported; for the list of available types
// see the explicit instantiation code at the end of lsst/afw/image/src/Image.cc
typedef afwImage::Image<int> ImageT;
int main() {
// Declare an Image; its pixels are not yet initialized.
ImageT img(lsst::geom::Extent2I(10, 6));
// Initialize all pixels to a given value.
img = 100;
// Alternatively you can specify an initial value in the constructor:
ImageT img2(img.getDimensions(), 100.0);
// Here is a common and efficient way to set all pixels of the image.
// Note that the end condition is only computed once, for efficiency.
for (int y = 0; y != img.getHeight(); ++y) {
for (ImageT::x_iterator ptr = img.row_begin(y), end = img.row_end(y); ptr != end; ++ptr) {
*ptr = 100;
}
}
// It is probably slower to compute the end condition each time, as is done here.
for (int y = 0; y != img.getHeight(); ++y) {
for (ImageT::x_iterator ptr = img.row_begin(y); ptr != img.row_end(y); ++ptr) {
*ptr = 100;
}
}
// STL-compliant iterators are available.
// However, they are not very efficient because the image data may not be contiguous
// so these iterators must test for end-of-row on every increment.
// (By the way, we do guarantee that an image's row data is contiguous).
// iterator
for (ImageT::iterator ptr = img.begin(), end = img.end(); ptr != end; ++ptr) {
*ptr = 100;
}
// reverse_iterator
for (ImageT::reverse_iterator ptr = img.rbegin(), end = img.rend(); ptr != end; ++ptr) {
*ptr = 100;
}
// A different way of choosing begin() for use with (inefficient) iterator
for (ImageT::iterator ptr = img.at(0, 0), end = img.end(); ptr != end; ++ptr) {
*ptr = 100;
}
// There is one efficient STL-compliant iterator: "fast_iterator", but it only works for contiguous images
// (such as newly allocated images). If you attempt to use this on a subimage you will get an exception.
for (ImageT::fast_iterator ptr = img.begin(true), end = img.end(true); ptr != end; ++ptr) {
*ptr = 100;
}
// It is possible to traverse the image by columns instead of by rows,
// but because the data is row-contiguous, this has awful consequences upon cache performance.
for (int x = 0; x != img.getWidth(); ++x) {
for (ImageT::y_iterator ptr = img.col_begin(x), end = img.col_end(x); ptr != end; ++ptr) {
*ptr = 100;
}
}
// If you must traverse the image by columns then consider doing it in batches to improve
// cache performance, as shown here:
int x = 0;
for (; x != img.getWidth() % 4; ++x) {
for (ImageT::y_iterator ptr = img.col_begin(x), end = img.col_end(x); ptr != end; ++ptr) {
*ptr = 100;
}
}
for (; x != img.getWidth(); x += 4) {
for (ImageT::y_iterator ptr0 = img.col_begin(x + 0), end0 = img.col_end(x + 0),
ptr1 = img.col_begin(x + 1), ptr2 = img.col_begin(x + 2),
ptr3 = img.col_begin(x + 3);
ptr0 != end0; ++ptr0, ++ptr1, ++ptr2, ++ptr3) {
*ptr0 = *ptr1 = *ptr2 = *ptr3 = 100;
}
}
// Save the image to disk
img.writeFits("foo.fits");
return 0;
}
y
int y
Definition: SpanSet.cc:49
lsst::afw::image
Backwards-compatibility support for depersisting the old Calib (FluxMag0/FluxMag0Err) objects.
Definition: imageAlgorithm.dox:1
geom.h
Image.h
lsst::jointcal.check_logged_chi2.main
def main()
Definition: check_logged_chi2.py:272
end
int end
Definition: BoundedField.cc:105
image
afw::table::Key< afw::table::Array< ImagePixelT > > image
Definition: HeavyFootprint.cc:216
x
double x
Definition: ChebyshevBoundedField.cc:277
ptr
uint64_t * ptr
Definition: RangeSet.cc:88
lsst::afw::image::Image
A class to represent a 2-dimensional array of pixels.
Definition: Image.h:58
lsst::geom::Extent< int, 2 >