2018-05-12 11:42:56 -0600 | received badge | ● Popular Question (source) |
2017-08-22 04:35:40 -0600 | received badge | ● Famous Question (source) |
2015-10-09 08:35:22 -0600 | received badge | ● Notable Question (source) |
2015-02-12 17:34:09 -0600 | received badge | ● Famous Question (source) |
2014-08-21 08:53:25 -0600 | received badge | ● Popular Question (source) |
2014-05-14 00:25:27 -0600 | received badge | ● Notable Question (source) |
2014-03-27 02:02:21 -0600 | received badge | ● Good Question (source) |
2014-02-03 10:57:00 -0600 | received badge | ● Popular Question (source) |
2013-08-29 09:46:33 -0600 | received badge | ● Nice Question (source) |
2013-06-09 14:09:30 -0600 | answered a question | How to save only ROI pixels in a Mat using a binary mask? Thanks for the answers and comments, they have been useful. The problem has been resolved by iterating over the image's pixels manually and keeping only those where the mask's bit is set to white. I've tried this before but it didn't work. What I've noticed to be the reason, if not other factors as well:
|
2013-06-06 05:09:39 -0600 | asked a question | How to save only ROI pixels in a Mat using a binary mask? I have the binary mask of an image, in a Mat object. I want to pass only the ROI (Region Of Interest) pixels (set to white in binary mask), without the background (that is set to black in the binary mask) to a colour-quantisation module. Question is how? I have tried the Bounded rectangles, as far as I understand (have not tried), have the disadvantage of potentially adding extra background pixels that are not needed, as well as finding reasonable boundary values, which is not preferred in this case. Any idea how to save a Mat with only the pixels needed (set) from a binary mask? It's the pixels that matter, thus it's fine if the image is reshaped, provided only ROI pixels are stored. It's a common CV problem, but I am yet to find a solution that worked. I'm using OpenCV on Android (Java API), but it's the technique that matters the most (hopefully, if possible, with OpenCV example code for better understanding), that should be cross-platform. Thank you in advance. |
2013-05-26 11:09:48 -0600 | asked a question | Obtaining nearest neighbors using knn on Android There's a question here that asks about how to obtain the nearest neighbors using knn, which as far as I know could be retreived using the optional parameter As far as I know, I don't suppose the distances values, Is there a certain way to obtain the neighbors original values, in Android, without using Android NDK - just using the java API? Thank you in advance. |
2013-03-31 10:46:45 -0600 | commented answer | Colour Quantization Thanks for the detailed answer. If possible though; can some documentation be added to the code to highlight the key tasks for further elaboration? |
2013-03-13 17:04:21 -0600 | answered a question | Best way to store a Mat object in Android Thank you for the answers and comments. I prefer not to use Android NDK at the moment, and thus have tried saving Mat objects as
I still need to try this method in more depth, but I think it should offer a reasonable alternative. |
2013-03-10 16:54:40 -0600 | received badge | ● Student (source) |
2013-03-10 15:24:28 -0600 | asked a question | Best way to store a Mat object in Android What is the best way to store a Mat object in Android? (there is a similar, unanswered, question here) In image processing apps; it requires quite a lot of processing time to perform necessary pipelines which could be redundant. Thus, Mats would be preferably stored to prevent re-computation every time. I considered using SQLlite databases, but those seem to add unnecessary complexity in reading and writing Mat objects, where the method I understand would be writing each individual pixel in a Mat object in a separate row. I came across solutions (regarding saving custom classes, not OpenCV in specific) that suggested saving the file externally to the SD card. That seems quite plausible, but the problem is that class Mat must implement Are there any time, and memory, efficient ways to preserving Mat objects for later launches of the app? Thank you for your time. |
2013-03-10 12:52:17 -0600 | received badge | ● Scholar (source) |
2013-03-10 12:52:04 -0600 | received badge | ● Supporter (source) |
2013-03-10 12:51:16 -0600 | commented answer | How to get and modify the pixel of Mat in Java? Thanks for the answer. However I don't quite understand the use of the byte array. I tried, based on the above suggestion, using m.get(0, 0, buff), and m.get(0,0)[0] (for a grayscale image). The latter resulted in the expected value; the former however (using the byte array) gave a large value (exceeding 255) that I don't understand. My image is of type CV_8U. |
2013-03-10 01:34:29 -0600 | asked a question | Accessing pixels in Mat using Android (Java API) I am trying to access pixels' intensity values in Mat objects (image mats and histogram mats to be specific; such as gray scale value in gray scale images) and am unsure how to do so using the Java API (not NDK).
In short; how do I access a pixel's intensity value in a Mat (single or multi-channel) using the OpenCV Java API in Android? |