Imatest edge spatial frequency response (eSFR) test chart
An esfrChart
object stores the positions and measurements
of regions of interest of the Extended Imatest® edge spatial frequency response (eSFR) test chart [1], [2].
The Extended eSFR test chart is a version of the ISO 12233:2014 standard test chart with a 16:9 aspect ratio and extra visual features such as additional slanted edge ROIs.
chart = esfrChart(A)
creates an
esfrChart
object and sets the Image
property from input image
A
.
chart = esfrChart(A,'Sensitivity',
creates an s
)esfrChart
object, using sensitivity
s
during chart import.
chart = esfrChart(A,'RegistrationPoints',p)
creates an
esfrChart
object and sets the RegistrationPoints
property from points in
argument p
.
measureSharpness | Measure spatial frequency response using Imatest eSFR chart |
measureChromaticAberration | Measure chromatic aberration at slanted edges using Imatest eSFR chart |
measureNoise | Measure noise using Imatest eSFR chart |
measureColor | Measure color reproduction using test chart |
measureIlluminant | Measure scene illuminant using Imatest eSFR chart |
displayChart | Display test chart with overlaid regions of interest |
For accurate and reliable results, acquire an image of the test chart according to standard specifications outlined in the ISO standard and by the manufacturer [2], [3]. As a simple guideline, align the chart horizontally on a light background. Cover over 90% of the field of view with the chart, but ensure that the top and bottom edges of the chart are still visible. For reliable measurements, set the minimum image width to at least 500 pixels.
You can capture an image of the Extended eSFR test chart at the full 16:9 aspect ratio, or at an aspect ratio of 3:2 or 4:3, as specified on the chart.
To ensure that the chart is properly imported, visually verify the test chart
image using the displayChart
function.
[1] Imatest. "Esfr". http://www.imatest.com/mathworks/esfr/.
[2] Using eSFR ISO Part 1. URL: http://www.imatest.com/docs/esfriso_instructions.
[3]