Blog
The latest news from Google AI
Introducing Translatotron: An End-to-End Speech-to-Speech Translation Model
Wednesday, May 15, 2019
Posted by Ye Jia and Ron Weiss, Software Engineers, Google AI
Speech-to-speech translation systems have been developed over the
past several decades
with the goal of helping people who speak different languages to communicate with each other. Such systems have usually been broken into three separate components:
automatic speech recognition
to transcribe the source speech as text,
machine translation
to translate the transcribed text into the target language, and
text-to-speech synthesis
(TTS) to generate speech in the target language from the translated text. Dividing the task into such a
cascade
of systems has been very successful, powering many commercial speech-to-speech translation products, including
Google Translate
.
In “
Direct speech-to-speech translation with a sequence-to-sequence model
”, we propose an experimental new system that is based on a single
attentive sequence-to-sequence model
for direct speech-to-speech translation without relying on intermediate text representation. Dubbed
Translatotron
, this system avoids dividing the task into separate stages, providing a few advantages over cascaded systems, including faster inference speed, naturally avoiding compounding errors between recognition and translation, making it straightforward to retain the voice of the original speaker after translation, and better handling of words that do not need to be translated (e.g., names and proper nouns).
Translatotron
The emergence of end-to-end models on speech translation started in 2016, when researchers demonstrated
the feasibility
of using a single sequence-to-sequence model for speech-to-text translation. In 2017, we demonstrated that such end-to-end models can
outperform cascade models
. Many approaches to further improve end-to-end speech-to-text translation models have been proposed recently, including our effort on
leveraging weakly supervised data
. Translatotron goes a step further by demonstrating that a single sequence-to-sequence model can directly translate speech from one language into speech in another language, without relying on an intermediate text representation in either language, as is required in cascaded systems.
Translatotron is based on a sequence-to-sequence network which takes source
spectrograms
as input and generates spectrograms of the translated content in the target language. It also makes use of two other separately trained components: a neural
vocoder
that converts output spectrograms to time-domain waveforms, and, optionally, a speaker encoder that can be used to maintain the character of the source speaker’s voice in the synthesized translated speech. During training, the sequence-to-sequence model uses a
multitask objective
to predict source and target transcripts at the same time as generating target spectrograms. However, no transcripts or other intermediate text representations are used during inference.
Model architecture of Translatotron.
Performance
We validated Translatotron’s translation quality by measuring the
BLEU score
, computed with text transcribed by a speech recognition system. Though our results lag behind a conventional cascade system, we have demonstrated the feasibility of the end-to-end direct speech-to-speech translation.
Compared in the audio clips below are the direct speech-to-speech translation output from Translatotron to that of the baseline cascade method. In this case, both systems provide a suitable translation and speak naturally using the same canonical voice.
Input (Spanish)
Reference translation (English)
Baseline cascade translation
Translatotron translation
You can listen to more audio samples
here
.
Preserving Vocal Characteristics
By incorporating a speaker encoder network, Translatotron is also able to retain the original speaker’s vocal characteristics in the translated speech, which makes the translated speech sound more natural and less jarring. This feature leverages previous Google research on
speaker verification
and
speaker adaptation for TTS
. The speaker encoder is pretrained on the speaker verification task, learning to encode speaker characteristics from a short example utterance. Conditioning the spectrogram decoder on this encoding makes it possible to synthesize speech with similar speaker characteristics, even though the content is in a different language.
The audio clips below demonstrate the performance of Translatotron when transferring the original speaker’s voice to the translated speech. In this example, Translatotron gives more accurate translation than the baseline cascade model, while being able to retain the original speaker’s vocal characteristics. The Translatotron output that retains the original speaker’s voice is trained with less data than the one using the canonical voice, so that they yield slightly different translations.
Input (Spanish)
Reference translation (English)
Baseline cascade translation
Translatotron translation (canonical voice)
Translatotron translation (original speaker’s voice)
More audio samples are available
here
.
Conclusion
To the best of our knowledge, Translatotron is the first end-to-end model that can directly translate speech from one language into speech in another language. It is also able to retain the source speaker’s voice in the translated speech. We hope that this work can serve as a starting point for future research on end-to-end speech-to-speech translation systems.
Acknowledgments
This research was a joint work between the Google Brain, Google Translate, and Google Speech teams. Contributors include Ye Jia, Ron J. Weiss, Fadi Biadsy, Wolfgang Macherey, Melvin Johnson, Zhifeng Chen, Mengmeng Niu, Quan Wang, Jason Pelecanos, Ignacio Lopez Moreno, Tom Walters, Heiga Zen, Patrick Nguyen, Yu Zhang, Jonathan Shen, Orhan Firat, and Yonghui Wu. We also thank Jorge Pereira and Stella Laurenzo for verifying the quality of the translation from Translatotron.
Labels
accessibility
ACL
ACM
Acoustic Modeling
Adaptive Data Analysis
ads
adsense
adwords
Africa
AI
AI for Social Good
Algorithms
Android
Android Wear
API
App Engine
App Inventor
April Fools
Art
Audio
Augmented Reality
Australia
Automatic Speech Recognition
AutoML
Awards
BigQuery
Cantonese
Chemistry
China
Chrome
Cloud Computing
Collaboration
Compression
Computational Imaging
Computational Photography
Computer Science
Computer Vision
conference
conferences
Conservation
correlate
Course Builder
crowd-sourcing
CVPR
Data Center
Data Discovery
data science
datasets
Deep Learning
DeepDream
DeepMind
distributed systems
Diversity
Earth Engine
economics
Education
Electronic Commerce and Algorithms
electronics
EMEA
EMNLP
Encryption
entities
Entity Salience
Environment
Europe
Exacycle
Expander
Faculty Institute
Faculty Summit
Flu Trends
Fusion Tables
gamification
Gboard
Gmail
Google Accelerated Science
Google Books
Google Brain
Google Cloud Platform
Google Docs
Google Drive
Google Genomics
Google Maps
Google Photos
Google Play Apps
Google Science Fair
Google Sheets
Google Translate
Google Trips
Google Voice Search
Google+
Government
grants
Graph
Graph Mining
Hardware
HCI
Health
High Dynamic Range Imaging
ICCV
ICLR
ICML
ICSE
Image Annotation
Image Classification
Image Processing
Inbox
India
Information Retrieval
internationalization
Internet of Things
Interspeech
IPython
Journalism
jsm
jsm2011
K-12
Kaggle
KDD
Keyboard Input
Klingon
Korean
Labs
Linear Optimization
localization
Low-Light Photography
Machine Hearing
Machine Intelligence
Machine Learning
Machine Perception
Machine Translation
Magenta
MapReduce
market algorithms
Market Research
Mixed Reality
ML
ML Fairness
MOOC
Moore's Law
Multimodal Learning
NAACL
Natural Language Processing
Natural Language Understanding
Network Management
Networks
Neural Networks
NeurIPS
Nexus
Ngram
NIPS
NLP
On-device Learning
open source
operating systems
Optical Character Recognition
optimization
osdi
osdi10
patents
Peer Review
ph.d. fellowship
PhD Fellowship
PhotoScan
Physics
PiLab
Pixel
Policy
Professional Development
Proposals
Public Data Explorer
publication
Publications
Quantum AI
Quantum Computing
Recommender Systems
Reinforcement Learning
renewable energy
Research
Research Awards
resource optimization
Robotics
schema.org
Search
search ads
Security and Privacy
Self-Supervised Learning
Semantic Models
Semi-supervised Learning
SIGCOMM
SIGMOD
Site Reliability Engineering
Social Networks
Software
Sound Search
Speech
Speech Recognition
statistics
Structured Data
Style Transfer
Supervised Learning
Systems
TensorBoard
TensorFlow
TPU
Translate
trends
TTS
TV
UI
University Relations
UNIX
Unsupervised Learning
User Experience
video
Video Analysis
Virtual Reality
Vision Research
Visiting Faculty
Visualization
VLDB
Voice Search
Wiki
wikipedia
WWW
Year in Review
YouTube
Archive
2020
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2019
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2018
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2017
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2016
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2015
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2014
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2013
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2012
Dec
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2011
Dec
Nov
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2010
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2009
Dec
Nov
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2008
Dec
Nov
Oct
Sep
Jul
May
Apr
Mar
Feb
2007
Oct
Sep
Aug
Jul
Jun
Feb
2006
Dec
Nov
Sep
Aug
Jul
Jun
Apr
Mar
Feb
Feed
Follow @googleai
Give us feedback in our
Product Forums
.
