Questions tagged [object-detection]

Object detection deals with recognizing the presence of objects of a certain semantic class (e.g. “humans”, “buildings”, “cars”, &c) in digital image and video data.

Object detection is the branch of computer vision and that deals with recognizing objects of a certain semantic class (e.g. “humans”, “buildings”, “cars”, &c) as present within and data. Well-researched subdomains of object detection include and pedestrian detection.

Most contemporary algorithms for object detection employ some mode of image – such as or – coupled with a scheme for deriving meaning from the extracted and quantified image features.

Object detection has myriad applications, across many related disciplines: content-based image retrieval (or ), optical character recognition (or ), image recognition, and automated video surveillance.

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OpenCV cv::findHomography runtime error

I am using to compile and run code from Features2D + Homography to find a known object tutorial, and I am getting this OpenCV Error: Assertion failed (npoints >= 0 && points2.checkVector(2) == npoint s && points1.type() == points2.type()) in unknown…
haykart
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How can I rotate an image based on object position?

First off, sorry for the length of the post. I'm working on a project to classify plants based on an image of the leaf. In order to reduce the variance of the data I need to rotate the image so the stem would be horizontally aligned at the bottom of…
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How many images(minimum) should be there in each classes for training YOLO?

I am trying to implement YOLOv2 on my custom dataset. Is there any minimum number of images required for each class?
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LSTM object detection tensorflow

Long story short: How to prepare data for lstm object detection retraining of the tensorflow master github implementation. Long story: Hi all, I recently found implementation a lstm object detection algorithm based on this…
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SSD anchors in Tensorflow detection API

I want to train an SSD detector on a custom dataset of N by N images. So I dug into Tensorflow object detection API and found a pretrained model of SSD300x300 on COCO based on MobileNet v2. When looking at the config file used for training: the…
jeandut
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Show more images in Tensorboard - Tensorflow object detection

I am using Tensorflow's object detection framework. Training and evaluation jobs are going well, but in tensorboard I am only able to see 10 images for the evaluation job. Is there a way to increase this number to look at more images? I tried…
jood
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Tensorflow object detection evaluation pycocotools missing

Following the TF tutorial on pet object detection : https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/running_pets.md Ran locally :…
Frédéric Coubard
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Tensorflow Object Detection API on Windows - error "ModuleNotFoundError: No module named 'utils'"

I'm attempting to get the TensorFlow Object Detection API https://github.com/tensorflow/models/tree/master/research/object_detection working on Windows by following the install…
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Continued - Vehicle License Plate Detection

Continuing from this thread: What are good algorithms for vehicle license plate detection? I've developed my image manipulation techniques to emphasise the license plate as much as possible, and overall I'm happy with it, here are two samples. Now…
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Should I include negative examples for Tensorflow object detection API?

I am building a RCNN detection network using Tensorflow's object detection API. My goal is to detect bounding boxes for animals in outdoor videos. Most frames do not have animals and are just of dynamic backgrounds. Most tutorials focus on training…
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What's the correct way to compute a confusion matrix for object detection?

I am trying to compute a confusion matrix for my object detection model. However I seem to stumble across some pitfalls. My current approach is to compare each predicted box with each groundtruth box. If they have a IoU > some threshold, I insert…
ITiger
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Full body detection and tracking using OpenCV+Python-2.7

There are a lot of materials available to do this with C++. I would to know if there is a way to do full body detection using OpenCV in Python-2.7? Given video of a person walking along the sagittal plane (camera taken 90 degrees from the direction…
Ébe Isaac
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Why does linear svms work well with HoG descriptors?

Ok, almost all applications I have seen that use HoG features use linear svm as classifier. Can someone explain for me why linear svm are chosen and why they give good performance? Are linear svm chosen because it more simple and easier to train…
user622194
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Advanced square detection (with connected region)

if the squares has connected region in image, how can I detect them. I have tested the method mentioned in OpenCV C++/Obj-C: Advanced square detection It did not work well. Any good ideas ? import cv2 import numpy as np def angle_cos(p0, p1,…
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EMGU CV SURF image match

I have been working with the SURF feature detection example from the EMGU CV library. So far it's working amazingly; I can detect matching objects between 2 given images but I have run into a problem in regards to when the images do not match. I…
user1246856
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