I am working on a project where I have 1024x1024 brain images over time depicting blood flow. A blood flow parameter image is computed using the brain images over time, and is off the same dimension (1024 x 1024). My goal is to train a CNN to learn the mapping between the brain images over time and the blood flow parameter image.
I've looked into current CNN architectures, but it seems like most research on CNNs is either done for classification on single images (not images over time) or action recognition on video data, which I'm not sure my problem falls under. If anyone can provide me with any insight or papers I can read on how to train a model on temporal data, with the output being an image (rather than a classification score), that would be immensely helpful.
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I am trying to implement an image classification task for the grayscale images, which were converted from some sensor readings. It means that I had initially time series data e.g. acceleration or displacement, then I transformed them into images. Before I do the transformation, I did apply normalization across the data. I have a 1000x9 image dimension where 1000 represents the total time step and 9 is the number of data points. The split ratio is 70%, 15%, and 15% for training, validation, and test data sets. There are 10 different labels, each label has 100 images, it's a multi-class classification task.
An example of my array before image conversion is:
As you see above, the precisions are so sensitive. When I convert them into images, I am able to see the darkness and white part of the image;
Imagine that I have a directory from D1 to D9 (damaged cases) and UN (health case) and there are so many images like this.
Then, I have a CNN-network where my goal is to make a classification. But, there is a significant overfitting issue and whatever I do it's not working out. One of the architecture I've been working on;
Model summary;
I also augment the data. After 250 epochs, this is what I get;
So, what I wonder is that I tried to apply some regularization or augmentation but they do not give me kind of solid results. I experimented it by changing the number of hidden units, layers, etc. Would you think that I need to fully change my architecture? I basically consider two blocks of CNN and FC layers at the end. This is not the first time I've been working on images like this, but I cannot mitigate this overfitting issue. I appreciate it if any of you give me some solid suggestions so I can get smooth results. i was thinking to use some pre-trained models for transfer learning but the image dimension causes some problems, do you know if I can use any of those pre-trained models with 1000x9 image dimension? I know there are some overfiting topics in the forum, but since those images are coming from numerical arrays and I could not make it work, I wanted to create a new title. Thank you!
I am currently working on fingers-count deep learning problem. When you look at the dataset, images in the training and validation set are very basic and are almost the same. The network can achieve high training and validation accuracies. But when it comes to prediction in real-life images, it performs very badly(this is because the model has been trained on very basic images).
To overcome this, I converted the training and validation images to HSV(Hue-Saturation-Value) and trained the model on new HSV images. Example of 1 such image from new training set is:
I then convert my image from real life to HSV and pass it to model for prediction. But still, the model is not able to predict correctly. I assumed that since the training images and predicting image are almost same after applying HSV, the model should be predicting good. Is there something which I am thinking incorrectly here? Can HSV images be actually used for training CNN?
It seems you have the overfitting issue, and your model only memorize the simple samples of the training set and in contrast it can not generalize to more complex and diverse data.
In the context of Deep Learning there are various methods to avoid overfitting and I think you don't need to transform your input to HSV necessarily. First of all you can apply various data augmentation methods like random crop or rotation to create various versions of your data. If this method does not work, you can use a smaller model or applying techniques such as Drop Out or Regularization.
Here is a good tutorial from TensorFlow.
I want to train a facial recognition CNN from scratch. I can write a Keras Sequential() model following popular architectures and copying their networks.
I wish to use the LFW dataset, however I am confused regarding the technical methodology. Do I have to crop each face to a tight-fitting box? That seems impractical, as the dataset has 13000+ faces.
Lastly, I know it's stupid, but all I have to do is preprocess the images (of course), then fit the model to these images? What's the exact procedure?
Your question is very open ended. Before preprocessing and fitting the model, you need to understand Object Detection. Once you understand what object detection you will get answer to your 1st question whether you are required to manually crop every 13000 image. The answer is no. However, you will have to draw bounding boxes around faces and assign label to images if they are not available in the training data.
Your second question is very vague . What do you mean by exact procedure? Is it the steps you need to do or how to do preprocessing and fitting of the model in python/or any other language? There are lots of references available on the internet about how to do preprocessing and model training for every specific problem. There are no universal steps which can be applied to any problem
Im having problems in identifying the best way to optimize the custom vision model.
In using Image classification, will labeling the same image with different label at different time effect the precision of machine learning?
//for example labeling and training image A today with the label 't-shirt', labeling and training image A tomorrow with the label 'blue'.
//We are basically trying to input one classification at a time with the same image (total of five classification, such as style and color) and wanted to know whether this way will effect the prediction precision.
Will labeling larger amount of data at once when inputing the image for machine learning increase the precision of the model? (for example, will there be any difference between 50 label and 100 label for an image to learn at a time?)
Is there any way to teach machine learning to identify object recognition using the result gained from the image classification, else can i teach image classification and object recognition separately with the same type of image?
Will running the learning process of the machine learning longer (for example, the difference between 1hour and 10hours) always give better results?
I am training a CNN model(made using Keras). Input image data has around 10200 images. There are 120 classes to be classified. Plotting the data frequency, I can see that sample data for every class is more or less uniform in terms of distribution.
Problem I am facing is loss plot for training data goes down with epochs but for validation data it first falls and then goes on increasing. Accuracy plot reflects this. Accuracy for training data finally settles down at .94 but for validation data its around 0.08.
Basically its case of over fitting.
I am using learning rate of 0.005 and dropout of .25.
What measures can I take to get better accuracy for validation? Is it possible that sample size for each class is too small and I may need data augmentation to have more data points?
Hard to say what could be the reason. First you can try classical regularization techniques like reducing the size of your model, adding dropout or l2/l1-regularizers to the layers. But this is more like randomly guessing the models hyperparameters and hoping for the best.
The scientific approach would be to look at the outputs for your model and try to understand why it produces these outputs and obviously checking your pipeline. Did you had a look at the outputs (are they all the same)? Did you preprocess the validation data the same way as the training data? Did you made a stratified train/test-split, i.e. keeping the class distribution the same in both sets? Is the data shuffles when you feed it to your model?
In the end you have about ~85 images per class which is really not a lot, compare CIFAR-10 resp. CIFAR-100 with 6000/600 images per class or ImageNet with 20k classes and 14M images (~500 images per class). So data augmentation could be beneficial as well.