Section: Handle-Based Graphics
image
command has the following general syntax
handle = image(x,y,C,properties...)
where x
is a two vector containing the x
coordinates
of the first and last pixels along a column, and y
is a
two vector containing the y
coordinates of the first and
last pixels along a row. The matrix C
constitutes the
image data. It must either be a scalar matrix, in which case
the image is colormapped using the colormap
for the current
figure. If the matrix is M x N x 3
, then C
is intepreted
as RGB data, and the image is not colormapped. The properties
argument is a set of property/value
pairs that affect the
final image. You can also omit the x
and y
,
handle = image(C, properties...)
in which case they default to x = [1,size(C,2)]
and
y = [1,size(C,1)]
. Finally, you can use the image
function
with only formal arguments
handle = image(properties...)
To support legacy FreeMat code, you can also use the following
form of image
image(C, zoomfactor)
which is equivalent to image(C)
with the axes removed so that
the image takes up the full figure window, and the size of the
figure window adjusted to achieve the desired zoom factor using the
zoom
command.
512 x 512
pixels
square, and set the background to a noise pattern. We set the central
128 x 256
pixels to be white.
--> x = rand(512); --> x((-64:63)+256,(-128:127)+256) = 1.0; --> figure ans = 1 --> image(x) --> colormap(gray) --> quit
The resulting image looks like:
Here is an example of an RGB image
--> t = linspace(0,1); --> red = t'*t; --> green = t'*(t.^2); --> blue = t'*(0*t+1); --> A(:,:,1) = red; --> A(:,:,2) = green; --> A(:,:,3) = blue; --> image(A); --> quit
The resulting image looks like: