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2016-09-16 14:47:45 -0500 commented answer MSER detection error: detected region not extremal

I check mser.cpp in 3.0 version and it is different from the one in 2.4, but the functions are quite similar (like just name change). Can we verify that it is fixed now?

2016-09-16 14:44:47 -0500 commented question Read image from Amazon S3 directly to MAT with AWS SDK for C++?

Didn't check back this question for a while. Thanks a lot d9magai for your help

2016-03-24 17:38:16 -0500 received badge  Student (source)
2016-03-24 16:17:18 -0500 commented question In which case Mat data is in continuous memory block and which case is not?

@ Tetragramm: Thanks. I care more about the case where we surely have a continuous block of memory. As a matter of fact, I need to serialize a large Mat (may be of 100M rows and 128 columns, think of a visual dictionary in Bag-Of-Word model) and I need to do it right.

2016-03-24 16:14:31 -0500 commented question In which case Mat data is in continuous memory block and which case is not?

@matman: Thanks, I have read about basic Mat before asking the question but I could not find the answer for my question there. Sure it talks about storage but doesn't say about continuous block of memory or not.

2016-03-24 15:30:56 -0500 received badge  Editor (source)
2016-03-24 14:33:20 -0500 asked a question In which case Mat data is in continuous memory block and which case is not?

I know that OpenCV has the method isContinuous() to check. However, what I want to know is in which cases we know for sure that Mat data is in continuous memory block. So far, based on what I've been searching around, it seems that in these cases Mat data would be in continuous memory block:

  • Read an image using imread()
  • Create a new Mat using Mat() constructor
  • Using create() method
  • Using initializers like zeros(), ones(), etc.

In these cases Mat data would NOT be in continuos memory block:

  • Take ROI from an existing Mat
  • Take some columns from an existing Mat

Is it correct? Is there any other cases? Or can you provide a more generalized look? Please don't tell me that I should not worry about memory management as OpenCV takes care of it internally. It's much easier if we know for sure which cases we have continuous memory block.

Thanks a lot.

PS: The reason I come up with this question is from the accepted answer in SO: http://stackoverflow.com/questions/41...

in this part:

for (size_t dc = 0; dc < dataSize; ++dc) {
          ar & m.data[dc];
}

I think he assumes the Mat data is in continuous memory block, which I know is not always the case.

2016-02-13 00:24:20 -0500 commented question Read image from Amazon S3 directly to MAT with AWS SDK for C++?

Thanks Berak anyway. I'm reading the documentation of AWS SDK to read to buffer but has now luck so far.

2016-02-13 00:13:49 -0500 commented question Read image from Amazon S3 directly to MAT with AWS SDK for C++?

Hi Berak, I am trying to use aws sdk actually. My question is how? Thanks

2016-02-12 23:50:19 -0500 asked a question Read image from Amazon S3 directly to MAT with AWS SDK for C++?

Does anyone have experience with this AWS SDK for C++?

So for example, I have this image: https://s3-us-west-2.amazonaws.com/vs...

How can I read this image directly to MAT without saving it to disk using AWS SDK for C++?

Any help would be greatly appreciated!