Collaborating with Flight Simulator,
with the AI that we built...
this is a very awesome experience.
TTS stands for text-to-speech.
It's basically to convert text to audio,
that people can understand and experience.
In Flight Simulator,
the typical user scenario of the TTS is air traffic control.
And if you listen to the voices in the previous versions,
you can easily tell the voice is quite robotic.
Not everyone's an expert in the way an airplane should sound.
But everyone can tell you when a human voice doesn't sound correct.
Because of this, it makes it a real challenge
to procedurally generate the human voice in a way that's believable.
- Traditional TTS is a multi-step process.
So, it's very complex, and the quality is not optimal.
I mean, we could record all of the VO that we needed linearly,
but, it wasn't going to work because when we added up all the variables,
we were looking at line counts in the millions.
So that was quickly out of the picture.
In recent years,
we have heavily invested in deep learning TTS.
- Our goal is to build a human-like voice,
so that the player of Flight Simulator
is able to have an immersive experience
when they play the game.
The first challenges we have is definitely the quality
and how we can get those, kind of, naturalness.
Air traffic controllers don't necessarily speak in the the same way that,
say, a customer service representative would.
It's a very specific and transactional tone.
When it comes to the neural TTS,
in order to get a good voice,
it's better to have good data.
- To achieve that,
we built a universal TTS model,
based on 3,000 hours of data.
We actually accumulated tons of the data
so, that this universal model
is able to capture the nuance of the audio
and generate a more natural voice for the algorithm.
What we liked about Cognitive Service's Offerings
were that they had a much higher fidelity,
and they sounded a lot more like an actual human voice.
The second part is about the scalability.
We know that ATC has
hundreds of voices or thousands of voices
because there is different airports in the world.
There are more than fifty-thousand airports, thousands of different aircraft,
and an almost infinite combination of tail numbers
So, how can we help the developer
to have a scalable way to build the voice?
When the Flight Simulator come to the TTS,
we would like to use our pre-built TTS voices
to improve the variety of the ATC voices.
We can't have the pilot and the tower using the same voice
while they're communicating with each other.
Fortunately, Azure TTS
is built on top of Azure infrastructure,
so we have supported more than 100 voices
for developers to use off-the-shelf.
By leveraging those pre-built voices,
Flight Simulator can use the voices right away
and boost their quality.
We also talk about how we can build in the personality.
How we can build personalized experience
into Flight Simulator.
Customized Voice is a new technology
that we bring to the Cognitive Service.
Any developer can upload their own data,
and this self-serving portal
is able to build the voice font, on-the-fly.
This allowed us to record an actor,
and then create a voice model using that actor's voice.
Instead of, you have to write tons of code,
and you have to have a deep knowledge of machine learning,
they can define the voice persona
and build their own branded voice.
For each challenge, the quality, scalability,
and the customization,
we can address the challenge of building the TTS
into the Flight Simulator,
systematically and holistically.
When we started this project, we knew that radio communications between the pilot
and the air traffic controllers was going to be a huge part
of the experience for simmers.
Azure's Cognitive Service's Text-To-Speech has improved
even in the time that we've been using it.
And it continues to improve year over year.
I'm really excited for where it's headed,
and what the possibilities will be in the future.