Interactive Image Measurements

Create a custom interface to interactively measure objects in an image

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Start with an image of cells to measure a cell radius

In[1]:=

img1=ResourceData["Example""Interactive Image Measurements","cells"];

Create a viewer with controls for examining the details of the image, using

DynamicImage

In[2]:=

DynamicImageimg1,

...



Out[2]=

Use

EventHandler

and

MousePosition

to show a circle where the mouse is clicked on the dynamic image. Use Alt+click to position the center of a yellow measurement circle.
Move the slider to change the circle radius

In[3]:=

DynamicModule{center=ImageDimensions[img1]/2,r},ManipulateEventHandlerDynamicImageimg1,Epilog

circle and text

,{"MouseDown"If[CurrentValue["OptionKey"],center=MousePosition["Graphics"]]},PassEventsDownDynamic[Not[CurrentValue["OptionKey"]]],{{r,32},8,800},

...

,

...



Out[3]=

Consider another image to measure the length of a DNA strand by tracing it manually:

In[4]:=

img2=ResourceData["Example""Interactive Image Measurements","DNA"];

Use

EventHandler

and

MousePosition

to draw a line where the mouse is clicked on the dynamic image. Use Alt+click to place the vertices of a line. Alt+Shift+click deletes the last vertex:

In[5]:=

DynamicModule{pts={},length=0},Panel@EventHandlerDynamicImageimg2,Epilog

line and text

,{"MouseDown"If[CurrentValue["OptionKey"],If[CurrentValue["ShiftKey"],pts=Most[pts],AppendTo[pts,MousePosition["Graphics"]]];length=Total@Apply[EuclideanDistance,Partition[pts,2,1],{1}]]},

...



Out[5]=

Related Symbols

DynamicImage
EventHandler
MousePosition

Publisher Information

Contributed by: Wolfram Staff