Questions tagged [object-detection]

Object detection is a computer-vision and image-processing technique for locating instances of objects in images or videos. Common applications include face detection and object tracking. Object detection algorithms typically leverage machine learning or deep learning to produce meaningful results.

Filter by
Sorted by
Tagged with
22
votes
2answers
14k views

What is the difference between semantic segmentation, object detection and instance segmentation?

I'm fairly new at computer vision and I've read an explanation at a medium post, however it still isn't clear for me how they truly differ.
2
votes
0answers
42 views

Is it possible to modify the layers of the models present in the Tensorflow Object Detection API

I would like to know if there is any way in which we can change the base layers of the models offered by the Tensorflow Object Detection API and if so, is it possible to change things like pooling/...
1
vote
0answers
115 views

Understanding Faster R-CNN

I'm having some trouble understanding the way the Faster R-CNN algorithm works. Specifically, the way the authors describe the concept of anchors. In their paper from here they describe anchors in ...
0
votes
0answers
29 views

I can not find a pre-trained neural network model for object detection

A simple model is needed, but with good accuracy, mAP for detecting objects is preferably trained on COCO, preferably on ipynb (to run or train on google colab). The models from the Tensorflow (...
0
votes
0answers
74 views

How to change the neural network model to improve the accuracy of mAP without learning from 0, but retraining already trained model

how you can change the Faster R-CNN Resnet 101 or Faster R-CNN Inception Resnet V2 model to improve the accuracy of mAP detection without learning the model with 0, but retraining already trained ...
1
vote
1answer
173 views

What is a basic object detection/localization ML algorithm that can be used for my relatively simple image set?

I have a relatively simple object localization task. I have an image set that are either uniform or contain an 'object' consisting of a black circular shape at some position in the image. The labels ...
1
vote
0answers
52 views

Is there a metric for counting AND classification simultaneously?

I'm working on a project that mixes object detection and crowd counting. The metric for object detection is mAP, which combines the regression of the bounding boxes with the precision of the ...
1
vote
1answer
142 views

People detection methods

In my problem I want to distinguish people from other shapes in images e.g I want to accurately know how many people are in specific region of image (at least for small number of people, for crowded ...
2
votes
0answers
769 views

How to calculate Average Precision for Image Segmentation?

If I've understood things correctly, when calculating AP for Object Detection (e.g. VOC, COCO etc) the procedure is: collect up all the detected objects in your dataset sort the detections by their ...
3
votes
0answers
783 views

Bounding box regression in R-CNN

In R-CNN paper, they give the definition of the target values for bounding box regression Given that $(P, G)$ is a (prediction box, ground-truth box) pair of the form $(x, y, w, h)$ where $x, y$ is ...
3
votes
1answer
178 views

What is wrong with my Precision-Recall curve?

Hi, I found this: https://github.com/rafaelpadilla/Object-Detection-Metrics I prepared my data: ground-truth and prediction files with bounding boxes. but I got a very strange plot. What do you thing?
1
vote
2answers
36 views

Detection model - Training with class-instance limit-awareness

Is there a way to make a detection model aware of the maximal number of possible objects of a given class within a single image? For example in a toy case with 2 classes. If I know that in every ...
1
vote
0answers
102 views

Should images with multiple objects of the same class be used as training sample for multi-classes object detection models?

Let's say the model try to detect all the grapes on a branch of grapes. Can I use images of a grape branch with all the grapes labeled as a training sample? Will it affect the quality of the RPN ? Is ...
1
vote
0answers
308 views

YOLO v3 complete architecture

I am attempting to implement YOLO v3 in Tensorflow-Keras from scratch, with the aim of training my own model on a custom dataset. By that, I mean without using pretrained weights. I have gone through ...
1
vote
1answer
98 views

Action Recognition for multiple objects and localization

I want to ask questions regarding the action detection on the video with proposed frames. I've used Temporal 3D ConvNet for the action recognition on video. Successfully trained it and can recognize ...
1
vote
1answer
372 views

Detecting address labels using Tensorflow Object Detection API

I am experimenting with the Tensorflow Object Detection API on a Windows 7 machine. I am trying to detect US address labels (and similar blocks of text) as they appear on a piece of mail or an ...
2
votes
1answer
137 views

How to detect different brands of milk

I'm trying to create a object detection model to detect different type of milk. What is the best approach to achieve the result in the picture below? As you can see in the picture, this model did ...
2
votes
0answers
496 views

mAP using Tensorflow object detection API

After I train my object detector using the Tensorflow object detection API(to detect only cars), I get an mAP value around 0.32 while running the eval.py script. However, in the Tensorflow Detection ...
2
votes
1answer
171 views

what is the best approach to detect small objects with similar shape?

I'm working a model which detect different products in supermarket shelf. In the training data, there are a lot of objects with similar shape placed very close to or stacked to each others.(eg: milks ...
1
vote
1answer
2k views

Issues with training SSD on own dataset

I'm new to ML and trying to train a SSD300, with some Keras-Code github.com/pierluigiferrari/ssd_keras I found on github. For training I'm using an own (very small) dataset of objects that are not in ...
1
vote
1answer
704 views

Extracting the feature map in Tensorflow Object Detection API

I would like to know how can I extract the feature map of a mobilenet trained on tensorflow object detection API. I want to take that feature map in order to feed another classifier. Thanks!
1
vote
0answers
20 views

Is it beneficial to train 1 object detector for N classes vs N object detectors each for a different class?

I always wondered if training an object detector to recognize (let's say), dogs and cats performs better or worse than training 2 object detectors, one for cats only and one for dogs only. Would this ...
0
votes
1answer
801 views

mean average precision - pseudo code

There are many blog posts and threads concerning the computation of mAP, both for PASCAL and for COCO. Still, they do not answer some fundamental questions. I am listing here the flow as I understand ...
0
votes
1answer
350 views

Mask RCNN: Random predictions during inference for the same image

I recently trained the Mask RCNN (matterport's implementation) on some satellite images, but during inference mode, I'm getting random predictions for the same set of weights for the same image. That ...
1
vote
0answers
35 views

Keras - How to using Cnn trained model on video image.?

I have trained Cat and dog image using CNN with Python ( total 10K, 8K for training and 2K for testing ). I want to make prediction in a video. Video Contain both cat and dog at a single moment. How ...
1
vote
0answers
56 views

Using tensorflow object detection in another model

I am trying to use Tensorflow (tf) object detection API models in another custom model I built. Specifically, I am trying to do: jointly train tf object detection models Y with another model X. in a ...
0
votes
2answers
550 views

Tattoo Image Recognition - Should I Crop Training Data Background

I am trying to train a neural network to detect objects within a tattoo. I couldn't find any existing labeled dataset so I need to manually create and label my own. I only understand the basics of ...
2
votes
1answer
1k views

Very slow convergence with CNN [closed]

I am new to deep learning. I am working on training an SSD model on a set of small objects. I am using Adam gradient descent for optimization and a large input (800x800), but I seem to only get an ...
0
votes
1answer
715 views

How to increase accuracy of model from tensorflow model zoo?

Situation: My dataset is 70k images of people wearing clothes. Images are labelled: bbox position and class. There are 10 classes. I did 80:20 split. Categories are ...
1
vote
1answer
518 views

The mix of leaky Relu at the first layers of CNN along with conventional Relu for object detection

First of all, I know the usage of leaky RELUs and some other relevant leaky activation functions as well. However I have seen in a lot of papers on object detection tasks (e.g YOLO) to use this type ...
2
votes
0answers
453 views

Training detector without bounding box data

From what I can see most object detection NNs (Fast(er) R-CNN, YOLO etc) are trained on data including bounding boxes indicating where in the picture the objects are localized. Is there any model ...
0
votes
1answer
176 views

How to obtain and load a good initial data set for object localization?

I'm looking for a good data set for training a CNN based network to do object localization (i.e. a data set with class labels and bounding box data). What is a good initial data set to use? How can ...
1
vote
0answers
22 views

Does anyone have suggestions for how Goodfellow et al detected digits from the larger Street View images in their 2014 paper?

In their 2014 paper titled, "Multi-digit Number Recognition from Street View Imagery using Deep Convolutional Neural Networks", they write, We use an automated method (beyond the scope of this ...
3
votes
1answer
243 views

Get bounding boxes for adjacent instances of a single class in image

I have a dataset with thousands of music score pages and manually annotated bounding boxes for the individual bars: My objective is now to train a DNN that should ultimately be able to get these ...
3
votes
2answers
4k views

Bounding Boxes in YOLO Model

The YOLO model splits the image into smaller boxes and each box is responsible for predicting 5 bounding boxes. My question is how does the model make these bounding boxes for every grid cell ? Does ...
1
vote
1answer
595 views

SSD based on ResNet-101 doesn't improve over SSD-VGGNet

I am training a SSD model for detecting mobile cranes. The training dataset contains 1,000 images and test set over 400 images. About 200 epochs gave mAP 83%, but my target is 90%. So I trained SSD-...
1
vote
1answer
51 views

What does AR(max=1) mean?

http://cocodataset.org/#detection-eval "ARmax=1: AR given 1 detection per image" "AR is the maximum recall given a fixed number of detections per image, averaged over categories and IoUs." Above link,...
1
vote
0answers
87 views

Add training data to YOLO post-training

I've been playing around with YOLOv3 and obtaining some good results on the ~20 custom classes I trained. However, one or two classes look like they can use some additional training data (not a lot, ...
5
votes
2answers
619 views

What is difference between intersection over union (IoU) and intersection over bounding box (IoBB)?

Can someone give a detailed explanation IoU and IoBB along with that the differences between them.
1
vote
0answers
75 views

Training a convoltion neural network for localization

I am new into convolutional neural networks and I am trying to build a cnn for localization of object on tensorflow. Currently I am trying to replicate a cnn similar to that of Alexnet and then want ...
2
votes
2answers
972 views

Do you apply confidence threshold before calculating mAP for YOLOv2?

I've been using YOLO v2 for object detection and have been trying to use mAP for validating the model. For training I use a confidence threshold of 0.25, however I am unsure as to whether to apply ...
1
vote
1answer
72 views

Better to crop or compress training data?

I've been trying to make an object recogniser in Tensorflow and have used labelImg to classify large electrical transmission towers at varying distances. In order to make 10-16MP (~2-7MB) images train ...
1
vote
0answers
40 views

Detecting directions using Convolutional neural networks [closed]

I am working on a task where I have to detect damages on the vehicles and exactly where the damage has occurred. So I have to not only detect the damage on the door but also mentioned which door(front ...
3
votes
1answer
236 views

How to label "other" while labeling image for object detection/classification?

I want to train a model to recognize the different categories of food e.g. rice, burger, apple, pizza, orange and other things. After the first training, I realized that the model is detecting other ...
1
vote
1answer
35 views

Detecting person on the picture if we know it is there

I implemented an algorithm for pedestrian classification using Keras and Tensorflow and it is quite good, it has 96 percent accuracy on test data. It gives you information about existence of a person ...
5
votes
1answer
1k views

Does image's background matter for detector training (CNN)?

Does an image's background matter for detector/localisation in the training part (using CNN)? For example, if I want to make a face detector, which one is better as training dataset? Faces cropped ...
5
votes
1answer
6k views

What is the difference between tensorflow saved_model.pb and frozen_inference_graph.pb?

I've re-trained a model (following this tutorial) from the google's object detection zoo (ssd_inception_v2_coco) on a WIDER Faces Dataset and it seems to work if I use ...
3
votes
1answer
164 views

Object Detection classification

I am currently training a classifier for detecting resistors using TensorFlow Object Detection API. For that, I downloaded resistor images from ImageNet and I am currently labeling those who will be ...
2
votes
2answers
2k views

How to download images and bounding boxes from imageNet?

I am doing object detection for a specific class, say, chairs . I want to download images of chairs from imageNet. I also want to download the annotation xml files ...

1
3 4 5
6
7