I have been following tutorials from the official OpenCV documentations
However, I am hoping to find the images they used in the tutorials so that I can reproduce results. Is there a repository of those images somewhere?
Did you take a look at the source of opencv.
"opencv\sources\samples\data" contains most of these sample images in the archive.
Try opencv-extra, at least some of the tutorials use images from there.
For example:
Related
Drake noob here.
I tried running the drake_visualizer and geometry_inspector with my own ROS generated URDF that depicts and experimental setup with two UR10s. This throws two errors
PackageMap is not able to resolve certain mesh files of extension *.STL and *.DAE. This has been well catalogued in this link.
And ROS paths of the sort package://blah/blah do not seem to be resolved as well. I know this because the console throws the following error
Couldn't find package 'blah' in the supplied packagepath: PackageMap:
[EMPTY!]
In another stack question, one of the authors of the Drake repo suggested we can transform the .stl files during build time. I tried searching for how you can exactly do this but couldn't find anything. I have the feeling that I am missing something fundamental here. Any help would be appreciated.
Thanks in Advance
Using Russ's comment, what you need to do is the following
parser = Parser(plant)
parser.package_map().PopulateFromFolder("path/to/folder/containing/package.xml")
parser.AddModelFromFile("your.urdf")
There are many ways to populate the package map, as linked in Russ's comment
Does anyone has code examples reading hdf5 files in F#? I cannot find any examples on SO or google. I tried hdf5.net library but could not get it to work using Python example code.
While I haven't tried it, there is some sample code available at https://rodhern.wordpress.com/2013/02/17/hdf5-f-to-octave-example/
It's the only example I know of offhand.
After I compiled openCV libraries, I got the following directory:
opencv\build_2.4.9\samples\ocl
In this there are many sample codes. But no description is provided unless you read the complete code and run a couple of times to know what it does.
Are there any documentation for such sample codes? If not how do I go ahead?
OpenCV has got examples mentioned in their websites
http://docs.opencv.org/doc/tutorials/tutorials.html
Or refer to
Learning OpenCV: Computer Vision with the OpenCV Library
by Adrian Kaehler and Gary Rost Bradski
I am new to opencv and I am using opencv for windows. How can I see the source code for a specific function of an opencv library ? I just one want to get an idea of how that specific machine vision algorithm is implemented.
You can get the OpenCV source code from https://github.com/opencv. An easy way to find the header for a function is to open an explorer window in OPENCV_HOME\build\include (where is the location where you chose to install OpenCV) and use the search box to find the header file that contains your function - this will help you know what module it is in. Then you can search in OPENCV_HOME\modules\MODULE_NAME\src to find the source of the the function. This is even easier if you install a search tool like grepWin.
Looking at the source is almost essential for finding out why those pesky OpenCV exceptions are thrown. It also means that you can answer most things about OpenCV yourself without having to ask here.
Here is a direct link to an excellent source code search, courtesy of Github. This is a very straightforward way to find the implementation and internal usages of a function or type.
All the source is now on github:
https://github.com/opencv/opencv and you can use it's search functionalities as well.
I found the answer by Drew Noakes to be the most helpful, especially given the fact that repository structures keep changing over time.
To search in the code or in other places inside a repository using a keyword, the instructions here can be followed.
What would be even easier for first-timers however, would be to simply search for a key word in the github search bar. Then the appropriate advanced search option would generate the tags described in the the earlier linked tutorial.
I'm currently working on a project with OpenEXR and I would like to implement some Blob detection algorithms. To do this I figured that I could use OpenCV as it says in the documentation that it can open OpenEXR format files.
I have all the libraries installed and working as I've been doing other things. I open a simple jpg file with openCV cvLoadImage. It works fine. But when i try to open any .exr file it doesn't seam to like it. I get a gray window where there should be the image display.
Has anyone done any tests with OpenCV and OpenEXR libraries working together? Have they worked for you? What do you think?
Thanks.
Yes, that's done, I posted a Ticket in the OpenCV project at willowGarage and they made all needed changes, you now can use OpenEXR with OpenCV as before!
Great
My HDR tone mapping algorithm will work again, cool
Have a nice programming now ;o)
Alex
Well Alex!
My news aren't really encouraging... I tried to use OpenEXR with OpenCV but it's not doing it's work. It says in the documentation that OpenCV 2.0 has OpenEXR support but...
I've searched the web to find some example of working EXR images in OpenCV but had no luck.
At this time I've developed myself a function to convert an image read with the OpenEXR libraries that uses Ilm::Rgba* structure to save the pixels of the image and convert it to char* that OpenCV uses with images. The IlpImage structure is the one I use. Actually I'm working with an example from OpenFrameworks and using they're Image structure...
It's a really early stage in my development because I had to start over...
I hope this can help you... but if you enter the world of OpenEXR it's a pretty dark world in terms of documentation, so all I can say is good luck!
Feel free to contact me and I'll see if I can help you!
This question is rather old now, but I noticed whilst reading the OpenEXR manual today that it says (whilst talking about reading named channels)
If one of those channels is not present in the image file, the corresponding memory buffer for the pixels will be filled with an appropriate default value.
I'd speculate here that the grey image you are seeing is an "appropriate default value".