Dear Mohand Lagha

Digitizing is a four step process:

I am sorry I don't know such a software... I think that you should do it manually

yes I have done this manualy

But what about incertinties !!!!!!

What do you mean?

The errors with manually operations !!!!!

I've heard about such software. I will try to remeber and find its name!

I a m waiting !!!!!!!!!!!!!!!

Hi.. you can use the web or offline version. download from link (http://arohatgi.info/WebPlotDigitizer/tutorial.html)

There are many- The following pieces of software are good for this application:

1) Origin

2) ScanIt: https://www.amsterchem.com/scanit.html

3) DataThief: https://www.datathief.org/

4) Plotdigitizer: http://plotdigitizer.sourceforge.net/

5) Graphdigitizer: http://www.silkscientific.com/graph-digitizer.htm

6) Getdata- Graph-digitizer: http://getdata-graph-digitizer.com/

I hope this helps.

There is one software freely available online whose name is "Dexter". You can use it for this purpose. In case you wanna perform this in Origin then it is very much easy and available in the versions above 8.5.1. Check out this link to quickly learn this method - https://www.youtube.com/watch?v=42tl-Rxmj2A

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Dear Mohand Lagha

Digitizing is a four step process: