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Similarity calculation in copy move forgery detection

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TUSHAR MURATKAR 2017-9-29

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关闭： TUSHAR MURATKAR 2017-10-3

Hi everyone, i am having an cell array of 241x241. In that every cell is of 16x16 double. I want to find Euclidean distance between these cells only if abs[index(u)-index(v)] is less than or equal to Offset threshold. I am not getting how to code it in matlab. Any help in this will be greatly appreciated.

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Rik 2017-9-29

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What do you mean with Euclidean distance between cells? Can you provide small example input and desired result?

Have a read here and here. It will greatly improve your chances of getting an answer.

TUSHAR MURATKAR 2017-9-29

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@rik, Euclidean distance between cells means between blocks of that cell array.

Rik 2017-9-29

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编辑：Rik 2017-9-29

An array index is not necessarily a coordinate, which is why I asked the question. Your reply isn't really answering the question, but I think we can conclude from that that you mean the indices can be treated as coordinates.

As for my second question: can you give an example of what you mean with abs(index(u)-index(v))?

Another question: should all cells be compared with all other cells? That would need 241*241*240*240=3.3 million comparisons, so if that is the case, try finding a vectorized solution.

TUSHAR MURATKAR 2017-9-29

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@rik, u and v are blocks inside cell array. abs means absolute value. The answer to your last question is that to avoid compairing all cells with all other cells we have to use absolute value condition.

Rik 2017-10-2

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You will need to provide an example of what you want. If u and v are both inside each cell, you might be able to use cellfun to generate a binary map of which cells to include in your distance measurement.

charu shree 2017-10-2

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@rik....Can you help me with coding.

Rik 2017-10-2

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@charu, I might, but why don't you post a question of your own? In the past you have received help when you explained your question clear enough.

PS I don't think it is very polite to ask help in this way on someone else's question.

Jan 2017-10-2

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The Euclid distance is defined between vectors. Your elements are matrices, therefore it is still not clear, what you want to calculate.

TUSHAR MURATKAR 2017-10-2

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Hi John, i have an column vector of size 58081x1. I want to find Euclidean distance between them. Any help in this will be highly appreciated. Thanks in advance.

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