Adding noise in gprMax

[Santhu Athidi]

Dear all,

Is it possible to add random noise or additive white gaussian noise to B-scan image in gprMax? If possible how to add noise? 

Thank you in advance

[他我]

I also have similar questions, I hope you can help to answer questions, thank you！

[Craig Warren]

You can add whatever noise you like as a post-processing step to the output from gprMax. You could do this using Python or MATLAB - just import your B-scan data and add the noise.

Kind regards,

Craig

[Santhu Athidi]

It means we cannot add any noise in gprMax program itself, right sir? can you give some insights about adding surface roughness sir 

[Craig Warren]

You have to be careful with the definition of the word noise, and then the source of the noise. Noise can mean any signal(s) that are not from the target/object of interest in your model. For example, if you are trying to detect/image a buried pipe and you receive signals from the surrounding heterogeneous soil, then those could be considered noise. If you know what is generating the noise and can model it, then you can include it in your gprMax simulation.

For information on rough surfaces, see our docs:

• http://docs.gprmax.com/en/latest/input.html#add-surface-roughness

• http://docs.gprmax.com/en/latest/examples_advanced.html

Kind regards,

Craig

[Santhu Athidi]

Last statement is a bit confusing sir, if I want to add AWGN noise with SNR of 10dB or 20dB is it possible to add it in gprMax code(notepad file) itself. In some of researh articles they are adding this AWGN noise like this. are they adding noise after post processing in matlab or python or directly in gprmax codse itself?

[Antonis Giannopoulos]

You cannot add what you describe as AWGN noise directly in gprMax. In other words there is no option or gprMax command to add noise to your modelled data. You need to get the gprMax output in another environment (e.g. Python script, MATLAB, octave, etc.) and then process the gprMax data adding to them the noise characteristics you want. The previous answer from Craig is not confusing as you have not had specified what did you mean by noise. There are many sources of noise and some, like the one you want, is easy to add and is incoherent in terms of its nature. Some are different like clutter. It does not matter here but is a good distinction to know about. 

Hope this answers your question clearly.

Best

Antonis

[Santhu Athidi]

Thank you very much sir