Visual Generative Modeling: Using GANsformers to Generate Scenes

Written by whatsai | Published 2021/03/07
Tech Story Tags: artificial-intelligence | gans | generative-adversarial-network | computer-vision | visual-generative-modeling | transformer-architecture | youtubers | youtube-transcripts | web-monetization

TLDRvia the TL;DR App

This week we take a look at visual generative modeling. The goal is to generate a complete scene in high-resolution, rather than a single face image or object. This process is similar to StyleGAN, but it uses the GAN in a traditional generative and discriminative way, with convolutional neural networks.

Watch the Video:

Chapters:
0:00​ - Hey! Tap the Thumbs Up button and Subscribe. You'll learn a lot of cool stuff, I promise.
0:24​ - Text-To-Image translation
0:51 -​ Examples
5:50​ - Conclusion

References

Paper: https://arxiv.org/pdf/2103.01209.pdf
Code: https://github.com/dorarad/gansformer

Complete reference:
Drew A. Hudson and C. Lawrence Zitnick, Generative Adversarial Transformers, (2021), Published on Arxiv., abstract:
"We introduce the GANsformer, a novel and efficient type of transformer, and explore it for the task of visual generative modeling. The network employs a bipartite structure that enables long-range interactions across the image, while maintaining computation of linearly efficiency, that can readily scale to high-resolution synthesis.
It iteratively propagates information from a set of latent variables to the evolving visual features and vice versa, to support the refinement of each in light of the other and encourage the emergence of compositional representations of objects and scenes.
In contrast to the classic transformer architecture, it utilizes multiplicative integration that allows flexible region-based modulation, and can thus be seen as a generalization of the successful StyleGAN network.
We demonstrate the model's strength and robustness through a careful evaluation over a range of datasets, from simulated multi-object environments to rich real-world indoor and outdoor scenes, showing it achieves state-of-the-art results in terms of image quality and diversity, while enjoying fast learning and better data efficiency.
Further qualitative and quantitative experiments offer us an insight into the model's inner workings, revealing improved interpretability and stronger disentanglement, and illustrating the benefits and efficacy of our approach. An implementation of the model is available at https://github.com/dorarad/gansformer​."

Video Transcript

Note: This transcript is auto-generated by Youtube and may not be entirely accurate.
00:00
the basically leveraged transformers
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attention mechanism in the powerful stat
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gun 2 architecture to make it even more
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powerful
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[Music]
00:14
this is what's ai and i share artificial
00:16
intelligence news every week
00:18
if you are new to the channel and would
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like to stay up to date please consider
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subscribing to not miss any further news
00:24
last week we looked at dali openai's
00:27
most recent paper
00:28
it uses a similar architecture as gpt3
00:31
involving transformers to generate an
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image from text
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this is a super interesting and complex
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task called
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text to image translation as you can see
00:41
again here the results were surprisingly
00:43
good compared to previous
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state-of-the-art techniques this is
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mainly due to the use of transformers
00:49
and a large amount of data this week we
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will look at a very similar task
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called visual generative modelling where
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the goal is to generate a
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complete scene in high resolution such
01:00
as a road or a room
01:02
rather than a single face or a specific
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object this is different from delhi
01:06
since we are not generating the scene
01:08
from a text but from a trained model
01:10
on a specific style of scenes which is a
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bedroom in this case
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rather it is just like style gun that is
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able to generate unique and non-existing
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human faces
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being trained on a data set of real
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faces
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the difference is that it uses this gan
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architecture in a traditional generative
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and discriminative way
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with convolutional neural networks a
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classic gun architecture will have a
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generator
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trained to generate the image and a
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discriminator
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used to measure the quality of the
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generated images
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by guessing if it's a real image coming
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from the data set
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or a fake image generated by the
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generator
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both networks are typically composed of
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convolutional neural networks where the
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generator
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looks like this mainly composed of down
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sampling the image using convolutions to
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encode it
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and then it up samples the image again
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using convolutions to generate a new
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version
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of the image with the same style based
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on the encoding
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which is why it is called style gun then
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the discriminator takes the generated
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image or
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an image from your data set and tries to
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figure out whether it is real or
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generated
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called fake instead they leverage
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transformers attention mechanism
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inside the powerful stargane 2
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architecture to make it
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even more powerful attention is an
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essential feature of this network
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allowing the network to draw global
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dependencies between
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input and output in this case it's
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between the input at the current step of
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the architecture
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and the latent code previously encoded
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as we will see in a minute
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before diving into it if you are not
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familiar with transformers or attention
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i suggest you watch the video i made
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about transformers
02:54
for more details and a better
02:55
understanding of attention
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you should definitely have a look at the
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video attention is all you need
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from a fellow youtuber and inspiration
03:03
of mine janik
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kilter covering this amazing paper
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alright
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so we know that they use transformers
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and guns together to generate better and
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more realistic scenes
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explaining the name of this paper
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transformers
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but why and how did they do that exactly
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as for the y they did that to generate
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complex and realistic scenes
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like this one automatically this could
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be a powerful application for many
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industries like movies or video games
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requiring a lot less time and effort
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than having an
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artist create them on a computer or even
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make them
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in real life to take a picture of it
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also
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imagine how useful it could be for
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designers when coupled with text to
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image translation generating many
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different scenes from a single text
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input
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and pressing a random button they use a
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state-of-the-art style gun architecture
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because guns are powerful generators
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when we talk about the general image
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because guns work using convolutional
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neural networks
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they are by nature using local
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information of the pixels
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merging them to end up with the general
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information regarding the image
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missing out on the long range
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interaction of the faraway pixel
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for the same reason this causes guns to
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be powerful generators for the overall
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style of the image
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still they are a lot less powerful
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regarding the quality of the small
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details in the generated image
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for the same reason being unable to
04:27
control the style of localized regions
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within the generated image itself this
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is why they had the idea to combine
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transformers and gans in one
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architecture they called
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bipartite transformer as gpt3 and many
04:41
other papers already proved transformers
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are powerful for long-range interactions
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drawing dependencies between them and
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understanding the context of text
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or images we can see that this simply
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added attention layers
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which is the base of the transformer's
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network in between the convolutional
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layers of both the generator and
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discriminator
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thus rather than focusing on using
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global information and controlling
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all features globally as convolutions do
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by nature
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they use this attention to propagate
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information from the local pixels to the
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global high level representation
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and vice versa like other transformers
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applied to images
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this attention layer takes the pixel's
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position and the style gun to latent
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spaces w
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and z the latent space w is an encoding
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of the input into an intermediate latent
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space
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done at the beginning of the network
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denoted here
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as a while the encoding z is just the
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resulting features of the input at the
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current step of the network
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this makes the generation much more
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expressive over the whole image
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especially in generating images
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depicting multi-object
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scenes which is the goal of this paper
05:51
of course this was just an overview of
05:53
this new paper by facebook ai research
05:55
and stanford university
05:57
i strongly recommend reading the paper
05:59
to have a better understanding of this
06:00
approach it's the first link in the
06:02
description below
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the code is also available and linked in
06:05
the description as well
06:07
if you went this far in the video please
06:08
consider leaving a like
06:10
and commenting your thoughts i will
06:12
definitely read them and answer you
06:14
and since there's still over 80 percent
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of you guys that are not subscribed yet
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06:23
explained
06:24
thank you for watching
06:33
[Music]

Written by whatsai | I explain Artificial Intelligence terms and news to non-experts.
Published by HackerNoon on 2021/03/07