I was assigned a project (in school) for automated multiple choice test scoring and I do not know where to start.
I think his is a kind of popular program and you already know about it. Enter an image file scanned of the answer sheet and return results.
Everything I know about computer vision is a few examples of photo editing with OpenCV. I hope you can give me a few keywords related to the problem or maybe a couple of blog articles, documents and related libraries.
Is there any free open source programs that I can refer to?
Thanks!
Edit: Add 2 example of the answer sheet (sory that I cannot find a sheet in English):
I think there are basically two steps to the problem
bring the form into a normalized position
now you know where the boxes are and can look at them by thresholding the gray values in that region.
What methods to use for step 1 depends on your actual images and how much the vary. Do you have some example images you can upload?
Also I think it is a good idea, especially if you are a beginner, to start with some simple examples and work your way up from there by adding more and more variation.
Related
First, you need to know that I'm a beginner in this subject. Initially, I'm an Embedded System Developpers but I never worked with image recognition.
Let me expose my main goal:
I would like to create my own database of Logos and be able to
recognize them in a larger image. Typical application would be, for
example, to make a database of pepsi logos and coca-cola logos and
when I take a photo of a bottle of Soda, it tells me if it one of
them or an another.
So, here is my problem:
I first wanted to use the Auto ML Kit of Google. I gave him my
databases so it could train itself on it. My first attempt was to
take photos of bottle entirely and then compare. It was ok but not
too efficient. I then tried to give him only logos but after
training, it couldnt recognize anything in the whole image of a
bottle.
I think I didn't give enough images in the first case. But I'd prefer to use the second case (by giving only logo) so that the machine would search something similar in the image.
Finally, my questions:
If you've worked with ML Kit from Google, were you able to train a
model by giving images that should be recognized in a larger image?
If yes, do you have any hints to give me?
Do you know reliable software that could help me to perform tests of this kind? I thought about Azure Machine Learning Studio from
Microsoft (since I develop on Visual Studio).
In a first time, I'd like to code as few as I can just for testing. Maybe later I could try to code my own Machine Learning System but I think it's a big challenge.
I also thought that I would need to split my image in smaller image and then send each of this images into the Machine but it would be time consuming and I need a fast reaction (like < 2 seconds).
Thanks in advance for your answer. I don't need complete answer with full tutorial (Stack Overflow is not intended for that anyway ^^) but just some advices would already be good.
Have a good day!
Azure’s Custom Vision is great for this: https://www.customvision.ai
Let’s say you want to detect a pepsi logo. Upload 70 images of products with the logo on them. Use Custom Vision to draw a box around the logo for each photo. Click “train”, and you get a tensorflow model with code.
Look up any tutorial for it, it’s pretty incredible and really easy to use.
I mean recorded data of multiple Neurons with multi-electrode. I need this data as the input for my experiment.
Google just released a Beta Dataset Search Engine.
You can find data Here
A good way to tackle stuff like this is to email the various labs that work with or generate data of your particular interest. A lot of labs I have worked for in the past have tons of data lying around that is not used, or usefull for them in any current way, and people are generally enthousiastic about your interest in their study.
Adittionally, there are many projects funded with the idea of sharing data and tools for the benefit of science. One such project is the miniscope project from UCLA (which has a ton of calcium imaging data lying around and have very helpfull people willing to share and assist you in the analysis. I am sure a quick google around can help you find similar labs more specialized in electrofysiology over calcium imaging.
I hope you find what your are looking for!
I know how to apply two effects to images -- blurring and making them grayscale. However, I would like to expand my knowledge further and learn more things of this nature.
I decided to Google them but found out that I do not even know what they are called.
I would like to ask: How do I progress further into image processing?
Image processing is a very big area with many applications.
These applications go from medical imaging, data compression and many
commercial applications like the ones you find in photoshop.
Without knowing where you are going to apply image processing, I assume
that you want to learn for the sake of curiosity :).
Today we have lots of online courses that make learning more easy.
I did an image processing course by Guilhermo Sapiro on the coursera
website that helped a lot https://www.coursera.org/course/images .
The course has already ended but the video classes are also available
on youtube. http://www.youtube.com/watch?v=GWCB3pKi2ko ( One about histogram equalization
you can see others on the related videos)
Another source is the amazing book by Rafael gonzales calle Digital Image Processing.
If you're looking for a website solution this is a good guide to how to use the css filter effect: http://www.html5rocks.com/en/tutorials/filters/understanding-css/
If you're looking for something else, I think more detail on your application is needed.
I downloaded the EverNote API Xcode Project but I have a question regarding the OCR feature. With their OCR service, can I take a picture and show the extracted text in a UILabel or does it not work like that?
Or is the text that is extracted not shown to me but only is for the search function of photos?
Has anyone ever had any experience with this or any ideas?
Thanks!
Yes, but it looks like it's going to be a bit of work.
When you get an EDAMResource that corresponds to an image, it has a property called recognition that returns an EDAMData object that contains the XML that defines the recognition info. For example, I attached this image to a note:
I inspected the recognition info that was attached to the corresponding EDAMResource object, and found this:
the xml i found on pastie.org, because it's too big to fit in an answer
As you can see, there's a LOT of information here. The XML is defined in the API documentation, so this would be where you parse the XML and extract the relevant information yourself. Fortunately, the structure of the XML is quite simple (you could write a parser in a few minutes). The hard part will be to figure out what parts you want to use.
It doesn't really work like that. Evernote doesn't really do "OCR" in the pure sense of turning document images into coherent paragraphs of text.
Evernote's recognition XML (which you can retrieve after via the technique that #DaveDeLong shows above) is most useful as an index to search against; the service will provide you sets of rectangles and sets of possible words/text fragments with probability scores attached. This makes a great basis for matching search terms, but a terrible one for constructing a single string that represents the document.
(I know this answer is like 4 years late, but Dave's excellent description doesn't really address this philosophical distinction that you'll run up against if you try to actually do what you were suggesting in the question.)
Does it happen that no one ever needs histogram in Delphi ?
Google gave me a bunch of half-baked code snippets. But it means that each time you need one - you have to invent one more ad hoc bycicle.
Torry mostly told me about some very expensive closed source Math Statistics or Financial packages, that as a subproduct have histograms. But they are very expensive and since you have no source code, each time you install update onto IDE/RTL/VCL you're probably screwed, until the vendor would make (soon ? ever?) updated packages. Given thatvendor is still does exists.
S.O. told me nothing, nil.
For what i found...
Mitov.com provides some histograms in PlotLab. which told to be free for non-commercial. Alas, it is again closed-source, and if the Histogram - quite fancy let's admit -is the onlything i need from it - why pay the whole price ?
One more example http://DSpatial.sf.net
Just few years ago i used it in Delphi 5, but even then i felt the author is loosing interest in the project. I made few enhancement, fixed some bugs, he merged them and that's all. The component was not very useful and lacked upon features, yet better than nothing. Now the project seems to be completely dead. Good old days, etc. But i do not want them back :-)
And Stack Overflow seemingly carries no single question about it. But maybe just no one bothered to create topic, after search found nothing ? I mean, Delphi was created for database access, histograms are one of basic ways to visualize data, and no one crosses them ? Something with nice style, with rich mouse tooltip like in HTML/CSS/JS on http://www.moskva.fm/stations/FM_95.2 ?
Or is this too domain-related and not ever possible to have good abstraction ?
TChart is a control that ships with most versions of Delphi. TChart can be used to make histograms (bar charts) in style. The following give you some ideas about how to use it: http://www.digitalcoding.com/tutorials/delphi/Simple-steps-to-create-Delphi-chart.html and http://delphi.about.com/od/adptips2006/qt/chart_selectbar.htm .
If you need something with code, google the pages at delphiforfun.org/programs/oscilloscope.htm . These are not controls. The oscilloscope article has a histogram with source. Some of the other projects at the site have other histogram graphs with source..not elegant but useful and free. Use them as a template to make your own control.
The link at http://delphiforfun.org/programs/Math_Topics/probability_distributions.htm shows how to make your own statistics displays with "histograms." This example makes use of TChart.
Here is some more stuff to try I found looking at my resource file:
http://wiki.lazarus.freepascal.org/TAChart, http://members.home.nl/mvanwesten/en_lazarus.html , http://www.martinole.org/TAChart.html ...some of these are GPU components that supposedly work with some versions of Delphi. Perhaps this is your lucky day as there is some source code. The first and third listed probably will work reasonably for histograms. You may have to write your own statistics algorithms.
Found this thread while doing some searching. The ImageEn component suite has a THistogramBox component. It's the NOT prettiest thing in the world, but it's the only one I've found so far.
http://www.imageen.com
I came across a histogram example in a gdiplus package available for download from code central. I don't know if it will do what you need but when I saw it I remembered your SO question.
HTH.
If you were using firemonkey, you could just created a series of TRectangles in series. They can be made unclickable by turning hittest off. Or is that too easy and straightforward?