Any Way to Convert TIF's or jpgs to Charts

[murphy00]

I am trying to find out if I can have Excel take a tripping curve in electronic file and either convert it to a chart or have Excel trace the curve. If you would like to see a tripping curve to know what I am talking about please click the link below and go to page 2. I can get them from the manufacturer in TIF format.

http://www.squared.com/us/products/circuitb.nsf/07a0210021262d45862564b5006e4f84/d30766b0d5e2d35385256abe00674359/$FILE/0600DB0105.pdf

Thank you,
Murph

[Damon Ostrander]

Hi Murph,

There is certainly no built-in Excel capability to do this. I have seen advertisements on the web for add-ins that enable one to manually digitize a graph in Excel, and you might want to look into this, but even this would be somewhat tedious. If at all possible, the best thing would be to go back to the application that is the source of the tif or jpg files to get the data that generated the graphic and import that into Excel.

[Jack in the UK]

Hi --

Can we not use Excels camra - which auto updtaes an all!

This is a picture ...

HTH
Rdgs
============
Jack

[MikeVV]

Excel 2003 and earlier (I don't know about 2007) have a capability that allows for digitizing anything graphical. In general, a user:

1) takes a graphical image (like a screen shot),
2) defines a data series on a worksheet,
3) pastes it into a scatter chart plot area,
4) clicks and drags the data points to match the image and
5) use the numbers in the updated data series.

This technique is very useful for a variety of tasks and is likely one of the most overlooked (or under utilized) features of Excel.

Specifically, for step 1), Using Windows XP and Excel 2003, I found a "trip curve" at:
http://ecatalog.squared.com/pubs/Cir...0600DB0105.pdf
and used the [Alt]+[PrintScreen] keys to capture it in the clipboard. I then used the MS Paint program [START]+[All Programs]+[Accessories]+[Paint] to crop the image to the extents of the plot data only (no margins) and saved it as a .bmp file.

I made note of the x-axis min and max values and the y-axis min and max values (they were "cropped out"). (1 to 100 and .01 to 1000) I was careful to crop the image precisely.

At step 2), I opened a new Excel workbook spreadsheet and defined two columns of x and y data with 7 rows of data. I entered values of (2.0,.05), (2.0,.10), (2.0,.50), (2.0,10), (2.0,100), (2.0,500) and (2.0,500) to provide an initial data series to digitize.

I then selected the range of x,y data and created a scatter chart uting the [chart wizard] toolbar command. I seleced datapoints connected by lines for the sub-type, turned off the legend and saved it on a new sheet. The resulting chart has a default plot area background and linear x-axis and y-axis.

During step 3), the x-axis and y-axis are defined a log-log using the "Format Axis > Scale" command. The axis scales must be set to the min and max values identified in step 1). The image captured in the first step is pasted into the plot area using the "Format Plot Area > Fill Effects > Picture Tab > Select Picture > Insert" dialog.

The original chart will appear beneath the data series in a manner that is "stretched" to fit the plot area. The proportions of data series and chard image will match if the image was properly cropped during step 1.

The data points on the scatter plat are clicked and dragged to match the underlying image during step 4). Hover the mouse over a data point, left-click once to select the series, left-click again to select the point and wait briefly for the curser to change into a four-pointed arrow. Left-click-drag a point in either the horizontal or vertical direction to lie above the image data. Do the same for the vertial or horizontal direction and observe that the numbers in the table have updated to the new position of the data point. Repeat this process for the remaining data points on the chart. (Note: if the "format data point" dialog appears, you have double-clicked the point. Cancel and click slower.)

The data in the series table can be used directly and adjusted by manually entering new values if desired in step 5). Additional series can be added to the chart to perform other calculations.

ANYTHING that can be seen on the computer screen can be digitized using this technique.