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Hi all, can we implement strategy in cluster like openlayer 2? I don't find any example to cluster with strategy in openlayer3. I want to cluster only a feature which have the same class like openlayer 2 do in example : http://dev.openlayers.org/examples/strategy-cluster-extended.html .. How to code it in openlayer 3? thx
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I was going through yolov4 paper where the authors have mentioned Backbone(CSP DARKNET-53), Neck (SPP followed by PANet) & than Head(YOLOv3). Hence is the architecture something like this:
CSP Darknet-53-->SPP-->PANet-->YOLOv3(106 layers of YOLOv3).
Does this mean YOLOv4 incorporates entire YOLOv3?
First, what is YOLOv3 composed of?
YOLOv3 is composed of two parts:
Backbone or Feature Extractor --> Darknet53
Head or Detection Blocks --> 53 layers
The head is used for (1) bounding box localization, and (2) identify the class of the object inside the box.
In the case of YOLOv4, it uses the same "Head" with that of YOLOv3.
To summarize, YOLOv4 has three main parts:
Backbone --> CSPDarknet53
Neck (Connects the backbone with the head) --> SPP, PAN
Head --> YOLOv3's Head
References:
Section 1.A. in https://ieeexplore.ieee.org/document/9214094
Page 5 of http://arxiv.org/abs/2004.10934
I am working on a project where my task is to identify machine part by its part number written on label attached to it or engraved on its surface. One such example of label and engraved part is shown in below figures.
My task is to recognise 9 or 10 alphanumerical number (03C 997 032 D in 1st image and 357 955 531 in 2nd image). This seems to be easy task however I am facing problem in distinguishing between useful information in the image and rest of the part i.e. there are many other numbers and characters in both image and I want to focus on only mentioned numbers. I tried many things but no success as of now. Does anyone know the image pre processing methods or any ML/DL model which I should apply to get desired result?
Thanks in advance!
JD
You can use OCR to the get all characters from the image and then use regular expressions to extract the desired patterns.
You can use OCR method, like Tesseract.
Maybe, you want to clean the images before running the text-recognition system, by performing some filtering to remove noise / remove extra information, such as:
Convert to gray scale (colors are not relevant, aren't them?)
Crop to region of interest
Canny Filter
A good start can be one of this tutorial:
OpenCV OCR with Tesseract (Python API)
Recognizing text/number with OpenCV (C++ API)
I went through tutorials on implementing Recommender System and most of them takes one variable (rank).
I want to implement an Item-Based Recommender System which takes multiple variables.
Eg : Let's say an Item (bar) has following varables (values ranging from -10 to +10, to express opposite polarities)
- price (cheap to expensive)
- environment (casual to fine)
- age range (young to adults)
Now I want to recommend items (bar) looking at the list of bars registered in User's history.
Is this kind of a "multi dimensional recommender system" possible to implement using Mahout or any other framework ?
You want the multi-modal, multi-indicator, multi-variable, how every you want to describe it—Universal Recommender. It can handle all this data. We've tested it on real datasets and get significant boost in precision test because of what we call "secondary indicators".
Good intuition. Give the UR a look: blog.actionml.com, check out the slides in one post. Code here: https://github.com/actionml/template-scala-parallel-universal-recommendation/tree/v0.3.0 Built on the new Spark version of Mahout: http://mahout.apache.org/users/algorithms/intro-cooccurrence-spark.html
What I m looking for is a function like this:
optimizeByLBFGS(CurrentParamters,GradientOfParamters,Loss/Cost) return: optimized paramters
Then I will use the returned optimized paramters and calculate the new loss/cost and feed them again ... and again... in this function. What can I use for this purpose?
Something like scipy.optimize.minimize in python for java?
Current paramters and gradients are availabe in a array / vector in the form of 100 rows and 1 column. Is something avaialbe
Thanks in advance!
There is one in Spark:
https://spark.apache.org/docs/1.0.1/api/java/org/apache/spark/mllib/optimization/LBFGS.html
And I heard that this one is nice too:
https://github.com/brendano/myutil/blob/master/src/util/LBFGS.java
Is there a way to search polygons which are inside another polygon with elasticsearch?
If not, is it possible with Solr or another system?
Totally possible on Elasticsearch:
http://elasticsearch-users.115913.n3.nabble.com/Can-I-use-geo-polygon-filter-to-retrieve-hits-based-on-polygon-fields-td4044079.html
I'm just looking into implementing it myself, my only worry is performance on a high traffic site so we'll see what happens.
As this post was a while ago it would be interesting to know what you ended up doing...
With Solr 4.3 it just became possible; I just finished working on it a couple weeks ago and I'm pretty excited about it. To learn how to use the new Solr 4 spatial field, see: http://wiki.apache.org/solr/SolrAdaptersForLuceneSpatial4 What's new is that you can now use the "IsWithin" and "Contains" predicates; there's "IsDisjointTo" too. Based on your question, it's not clear to me which of those you want. Imagine a 3-part sentence in which the first/left part is your index data, then there's the spatial predicate, then there's your query shape. So if you want to search for indexed shapes that are WITHIN your query shape, then use "IsWithin". I was just about to update the wiki to show these predicates.
Pretty sure it's not possible with ES.
With Solr + some plugins I think it's possible, but haven't tried it myself.
Have a look at https://github.com/spatial4j/spatial4j
Shape classes that are geospatially1 aware Shapes: Point, Rectangle,
Circle, Polygon (via JTS) shape intersection logic, yielding:
disjoint, contains, within, intersects bounding box area calculation
It seems spatial4J is already included in Solr. See David Smiley's response (author of Spatial4J and commiter to Solr) in the below link
How to install spatial4j into solr4