How to convert a scanned graph into real data

Have you ever had to pull data from an image of a graph? Maybe a supplier faxed you a 1940s era scan of the variable viscosity of peanut butter. Or, maybe your 401k administrator just sent you a glossy brochure showing historic portfolio performance (yay) and recent changes (boo).

Or, maybe you need to pull data off a chart like this one:

You could get out a ruler and start measuring just like you did in high school. Or, you could download an incredibly useful (and totally free) software tool to do the work for you.

Engauge Digitizer converts any image of a graph into numbers. The image can come from a scanner, digital camera, or screenshot. The tool lets you mark key numeric locations on the image, define the axes, and select the desired points/curves. Then, it magically converts everything into x/y point data that you can bring into Microsoft Excel for re-use.

Enjoy!

Filed Under: Random Upfront Thoughts, Technology
February 18, 2009
  • Jeff

    Thanks for posting this! I regularly use charts from spec. sheets and this is going to save me a TON of time and effort.

    • http://lifeupfront.com Jeff Waters

      Wow, my pleasure! Glad it helped.

  • Jeff Waters

    Hi Jeff, great to hear! Is it enough to win me a Bose noise canceling headset? (Just kidding)

  • Jeff Waters

    Hi Jeff, great to hear! Is it enough to win me a Bose noise canceling headset? (Just kidding)

  • mitesh

    thank you for this, so… much thanks… i cant say in words for this help…. thank you …

  • mitesh

    thank you for this, so… much thanks… i cant say in words for this help…. thank you …

  • Jeff

    Thanks for posting this! I regularly use charts from spec. sheets and this is going to save me a TON of time and effort.

    • http://lifeupfront.com/ Jeff Waters

      Wow, my pleasure! Glad it helped.

  • Anup

    Superb…i was blindly searching for this type of software without positive hope..But for my surprize, I got it!!!!! Thanks a ton…:)

  • http://lifeupfront.com/ Jeff Waters

    Glad it helped, thanks for stopping by!

  • MR3100

    Great tool. Thanks!
    Does anybody know how to convert the output data into uniform intervals?
    I’ve generated coordinates with random intervals but I need data that goes 1,2,3….

  • http://lifeupfront.com/ Jeff Waters

    Good question… I have no idea!
    Please post here if you find an answer.

  • ahmed

    thnx

    • http://lifeupfront.com/ Jeff Waters

      your welcome

  • Aj

    Nifty little software. Saving me a ton of time!

  • http://profiles.google.com/kbjeff Jeff Waters

    Glad you like it, AJ.

  • Sat7

    Thank you very much … It save me a lot of time .
    Thank u from Saudi Arabia :)

  • http://lifeupfront.com/ Jeff Waters

     My pleasure!

  • Mick Stevens56

    OMG, fantastic !!

    • http://lifeupfront.com/ Jeff Waters

      Mick, I believe you are the first person to type “OMG” on my blog! Thanks.

  • Mehrda Hojjati

    tnx dude. does anyone have any idea about getting an excel output out of it?

  • mehrdad

    tnx dude. does anyone have any idea about getting an excel output out of it?

  • http://lifeupfront.com/ Jeff Waters

    I think you just save out a .csv and open that in excel, right?

  • ibp

    This saved me so much time today! This is perfect for extracting data from spec sheets. And yes, you can export it as a .csv and open it an excel.

    • http://lifeupfront.com/ Jeff Waters

      Glad it helped!

  • FlowJoe

    Hi Jeff, I’ve never heard of Engauge Digitizer until today.  I’ve been using the Plot Digitizer program for several years and I think its interface is better.  I wanted to get your thoughts on it.  
    http://www.southalabama.edu/physics/software/plotdigitizer.htm

    • http://lifeupfront.com/ Jeff Waters

      Very cool FlowJoe, thanks!

  • Christoph

    Interesting, I have designed my own using some math software but as with all digitizer programs there is user input required.  And some fuzzy logic, as with your graph above, the y-axis is not exactly perpendicular so the values of the data points extracted will be, of course, only a fair approximation. 

    • http://lifeupfront.com/ Jeff Waters

      Yep– but the nature of going from analog to digital will always be a bit fuzzy.

    • Flow Joe

      Any good image editing program can be used to adjust the image to make the axes aligned correctly. I use the alignment tool in Paint Shop Pro.

      Also you must remember that this software tool is a step up from using a pencil and a straight edge, such as a ruler, and can be faster. The user’s job is not done after the data is collected from the software; sounds vaguely familiar to using an analysis program. One must review the numbers and consider the significant digits used in obtaining the numbers as well as the process in how the original data was measured with instruments.

  • Ibrahim Maged

    thanks

  • Hal

    Does anyone know if this program can be used for non-linear sets of data? I have lots of data that’s very volatile, and whenever I hit print screen, copy to paint, and import the image, Engauge Digitizer will give me the axis, but not the curve. Where am I going wrong? 

    • Flow Joe

      Try the Plot Digitizer program, I find that it’s very easy to use, never tried the Engauge software so don’t know how to compare.
      Here’s the link to download: http://www.southalabama.edu/physics/software/plotdigitizer.htm

      Also, MS Paint is no good at images.  A pay for software that’s ready good at snagging images, some editing and saving to different formats is Snag It by Techsmith.  And a free one that I like to use for dropping copied images, cropping and saving to almost any format is Irfanview (just google the name)… does some editing but is limited… cropping is really easy, just window and then Ctrl+Y.

    • http://lifeupfront.com/ Jeff Waters

      Not sure, Hal. Please post here when you get a solution. Thanks!