process image and plot graph

hey

i have a jpeg image of a graph (a simple temperature vs time graph, non linear curve). is it possible to use matlab to process the image and then recreate the graph in matlab, out-putting the x and y coordinates of say 100 points along the curve?

i have seen this done before, but have no clue how to do it myself!

thanks very much in advance!

Answer 1

[Sarah Wait Zaranek]

Jiro Doke has a tool (GRABIT) on File Exchange that allows you to pick points along the curve of a jpeg and then import them to ML. You could start there. You could use those points, fit them and/or interpolate them to get your 100 points along the curve.

link here

If you wanted to go and do it yourself, you could take the image and turn it into a logical matrix of ones and zeros based on color. Then you could use region properties to find your line and get the indices. From the indices, you could then pull out the x and y coordinates according to your axes scale.