Find the word from a string.

s1=hello everone (during the embedding process a watermark bit is embedded in the word)

s2=hello the everyone (By insertion attack 'the' word is inserted)

How can I find out that 'the' word is embedded during a attack and I also want to assign a 0 and 1 to the words. 0 indicates a new word and 1 presents a marked word.

Thanks in advance

[darova]

Tried strfind?

[Balkar Singh]

Thanks I'll try it

[Balkar Singh]

Sorry strfind is not working as per my reqirement. Thanks

[Stephen23]

Identifying character changes between two strings can be achieved using the Needleman-Wunsch algorithm:

https://en.wikipedia.org/wiki/Needleman-Wunsch_algorithm

You might find an implementation on FEX or online (but based on my experience implementing this algorithm in another language, it will be difficult to find a correct implentation).

If you want to resctrict yourself to matching whole words (so one different character means two words do not match), then you can simply split the strings up into words (e.g. strsplit, regexp), and then use ismember or something similar (one or two loops might be required).

Answer 1

[Sahithi Kanumarlapudi]

Hi,

Using 'strcmp' you could get the indices of the words which are not matching as per your requirement stated in the question. For more information on how to compare strings using 'strcmp refer to the following links

https://www.mathworks.com/help/matlab/matlab_prog/string-comparisons.htmlhttps://www.mathworks.com/help/matlab/ref/strcmp.html

If there is any other requirement, you could post it in the comments.

Hope this helps!

[Balkar Singh]

Thanks