Deep learning
is a machine learning technique that teaches computers to do what comes
naturally to humans: learn by example. Deep learning is a key technology behind
driverless cars, enabling them to recognize a stop sign, or to distinguish a
pedestrian from a lamppost. It is the key to voice control in consumer devices
like phones, tablets, TVs, and hands-free speakers. Deep learning is getting
lots of attention lately and for good reason. It’s achieving results that were
not possible before.
In
deep learning, a computer model learns to perform classification tasks directly
from images, text, or sound. Deep learning models can achieve state-of-the-art
accuracy, sometimes exceeding human-level performance. Models are trained by
using a large set of labeled data and neural network architectures that contain
many layers.
Why
does deep learning matters
In a word,
accuracy. Deep learning achieves recognition accuracy at higher levels than
ever before. This helps consumer electronics meet user expectations, and it is
crucial for safety-critical applications like driverless cars. Recent advances
in deep learning have improved to the point where deep learning outperforms
humans in some tasks like classifying objects in images.
How
deep learning works
Most deep
learning methods use neural network architectures, which is why deep
learning models are often referred to as deep neural networks.
The
term “deep” usually refers to the number of hidden layers in the neural
network. Traditional neural networks only contain 2-3 hidden layers, while deep
networks can have as many as 150.
Deep
learning models are trained by using large sets of labeled data and neural
network architectures that learn features directly from the data without the
need for manual feature extraction.
One of the
most popular types of deep neural networks is known as convolutional
neural networks (CNN or ConvNet). A CNN convolves learned
features with input data, and uses 2D convolutional layers, making this
architecture well suited to processing 2D data, such as images.
CNNs
eliminate the need for manual feature extraction, so you do not need to
identify features used to classify images. The CNN works by extracting features
directly from images. The relevant features are not pretrained; they are
learned while the network trains on a collection of images. This automated
feature extraction makes deep learning models highly accurate for computer
vision tasks such as object classification.
CNNs learn to
detect different features of an image using tens or hundreds of hidden layers.
Every hidden layer increases the complexity of the learned image features. For
example, the first hidden layer could learn how to detect edges, and the last
learns how to detect more complex shapes specifically catered to the shape of
the object we are trying to recognize.
Deep learning is a specialized form of machine learning. A
machine learning workflow starts with relevant features being manually
extracted from images. The features are then used to create a model that
categorizes the objects in the image. With a deep learning workflow, relevant
features are automatically extracted from images. In addition, deep learning
performs “end-to-end learning” – where a network is given raw data and a task to
perform, such as classification, and it learns how to do this automatically.
Another key difference is deep learning algorithms scale
with data, whereas shallow learning converges. Shallow learning refers to
machine learning methods that plateau at a certain level of performance when
you add more examples and training data to the network.
A key advantage of deep learning networks is that they
often continue to improve as the size of your data increases.
In machine
learning, you manually choose features and a classifier to sort images. With
deep learning, feature extraction and modeling steps are automatic
Machine
learning offers a variety of techniques and models you can choose based on your
application, the size of data you're processing, and the type of problem you
want to solve. A successful deep learning application requires a very large
amount of data (thousands of images) to train the model, as well as GPUs,
or graphics processing units, to rapidly process your data.
When
choosing between machine learning and deep learning, consider whether you have
a high-performance GPU and lots of labeled data. If you don’t have either of
those things, it may make more sense to use machine learning instead of deep
learning. Deep learning is generally more complex, so you’ll need at least a
few thousand images to get reliable results. Having a high-performance GPU
means the model will take less time to analyze all those images.
Comments
Post a Comment