I am looking for a library that could capture streams of images from webcam or USB camera, and then converting image data into multidimensional matrices, in order to do some mathematical operation on them; afterward saving the result as a png file.
I am stuck in the first step. It seems there is only opencv to capture images from camera, which uses highgui.dll for the job. Unfortunately after installing opencv using nimble install opencv, and running a simple code
import opencv/imgproc
import opencv/highgui
import opencv/core
var capture = captureFromCam(CAP_ANY)
the error could not load: (lib|)opencv_highgui(249|231|)(d|).dll arises. Opencv cannot find the library to import necessary functions from it. So far I could not find any way to overcome this issue. In standard libraries of Nim, there are two libraries serial and winim that if I am not wrong, are handling device ports. I could not find a simple way to use them. The question is, what is the proper library for handling devices and how to use them in a simple manner?
For the rest of the job (manipulating image data) I think pixie is a good library to use. It would be good to know, if there is better library, in simplicity and performance.
As Christoph said, the nim package seems years out of date. However if you download Version 249 and put the right dlls into your directory or link them through your nimble file, your code will run.
For your code you would need to copy from opencv\build\x64\vc12\bin files opencv_core249.dll, opencv_highgui249.dll and opencv_imgproc249.dll
You might want to instead just write a quick wrapper for the functions you need from a newer version yourself since you probably only need a few functions. You can look at the nim-opencv library for how to wrap functions.
Or you could use a different application to capture the footage and nim to process it.
Related
I just need to call cv::imread("xxx.jpg"), how can I compile the most simple lib of opencv?
You'd better use other frameworks other than OpenCV. OpenCV is extremely heavy for this kind of job. It's mainly focused on image processing.
Maybe you can use OpenImageIO, freeimage or other libs.
You can refer to these posts:
Reading an image file in C/C++
https://products.fileformat.com/image/cpp/openimageio
I am new to both openCV and Android. I have to detect objects in my project. So, I have decided to use ASIFT for the same. However, the code they have given here is very lengthy. It contains lots of C file. It also doesn't have openCV support.
Some search on the SO itself suggested that it is easier to connect the ASIFT code to the openCV library, but I can't figure out how to do that. Can anyone help me by giving some link or by telling the steps that I should use to add ASIFT to my openCv library, which I can further utilize in making my Android application?
Also, I would like to know whether using Android NDK along with JNI to make calls to the C files or using Android SDK along with binary package for my android project(Object Detection) would be a suitable option for me?
Finally , I solved my problem by using the source code given at the website of ASIFT developers. I compacted all the source files together to make my own library using make. I then called the required function from the library using JNI.
It worked for me, but the execution is taking approximate 2 mins on an Android device. Anyone having some idea about ways to reduce the running time ?
They used very simple and slow brute force matching (just for proving of concept). You can use FLANN library and it will help a lot. http://docs.opencv.org/doc/tutorials/features2d/feature_flann_matcher/feature_flann_matcher.html
I am interested in using a library that supports lip reading to augment audio/voice recognition. I found out that Intel's AVCSR (which was bundled with OpenCV library) would be an interesting option to consider. Would there be any other libraries that can be used to achieve the same (lip reading to augment voice recognition)?
Also I have not been able to locate a source to download this library from. I already tried the OpenCV package from SourceForge (http://sourceforge.net/projects/opencvlibrary/) but it does not seem to have the AVCSR packages/files. Could someone who has already worked with something similar point me to the place where I can find these source files (either within OpenCV or elsewhere)?
Thank you.
I'm looking to minimize the size of my android ndk built library.
I have started with the pre-built OpenCv libraries for Android and as of now the size of my lib is about 3MB. How can I minimize it's size?
I only need read/write files capability, png encode/decode, jpeg decoder and the typical image manipulation functions from OpenCv such as resize and cvtColor.
Any pointers greatly appreciated!
You've probably moved on with your project by now, Jona, but others not using the cmake-gui may like a command-line example. i.e. if you didn't want the CCALIB module, you could build like this:
cmake -DBUILD_OPENCV_CCALIB=OFF [other cmake flags] ../
Manipulating build flags may not cover all the module exclusions you would like, however, it's probably a good place to start. To see the list of flag options, open CMakeLists.txt file (top of the opencv source directory).
Turning on/off flags also won't break your builds as much as manually commenting-out code.
The OpenCV library has several modules, you might consider leaving out modules like 'highgui' and 'gpu', and maybe more depending on what you need and don't need. Anyhow, I am not quite sure what you need. Maybe you should use a different smaller library instead, as reading, writing, decoding, converting, etc are not really Computer Vision operations, like a Hough transform or a distance map
One you might consider is cimg btw, you can easily strip that one down as it simply just defines more and more functions as part of the cimg class.
Good luck!
I'm developing a BlackBerry application in which I need to unpack a zip file compressed with PKZIP. The package could have one file in it, or it could have 10; it will vary in each case. I know that the BlackBerry API has native support for GZip and Zlib, although I'm pretty sure that these methods aren't going to be helpful in my case. It doesn't look as if I can extract the individual files using these calls.
I've tried JZlib (http://www.jcraft.com/jzlib/), which compiled fine, but again it doesn't look as if the methods contained therein are going to allow me to pull the individual files.
It appears as if this is possible, as there's an application called Ziplorer (http://www.s4bb.com/software/ziplorer/) that claims to do perform this exact procedure. How they're doing it, however, escapes me.
So here I am after hours of Googling. I'm welcoming any insight into my problem with open arms.
"zip" algorithms are typically offshoots of the Lempel-Ziv-Welch algorithm. They are a fairly efficient stream compression algorithms, but because of how they function, you can't start to decompress at random points in the file, you have to start from the start.
Any product that claims to be able to decompress one file from a zip still has to decompress everything before it in the zip file in order to know how to decrypt the given file, or even, for that matter, where the file is in the archive.
If you can tolerate GPL code in your application, then this library http://jazzme.sourceforge.net/ that might work. However the project (and its parent project http://sourceforge.net/projects/jazzlib/) don't look like they're being developed.