Deep Noise Suppression Challenge – INTERSPEECH 2021


The Deep Noise Suppression (DNS) challenge is designed to foster innovation in the area of noise suppression to achieve superior perceptual speech quality. We recently organized a DNS challenge special session at INTERSPEECH 2020 and ICASSP 2020. We open-sourced training and test datasets for the wideband scenario. We also open-sourced a subjective evaluation framework based on ITU-T standard P.808, which was used to evaluate challenge submissions. Many researchers from academia and industry made significant contributions to push the field forward, yet even the best noise suppressor was far from achieving superior speech quality in challenging scenarios. In this version of the challenge organized at INTERSPEECH 2021, we are expanding both our training and test datasets to accommodate full band scenarios. The two tracks in this challenge will focus on real-time denoising for (i) wide band, and (ii) full band scenarios. We are also making available a reliable non-intrusive objective speech quality metric for wide band called DNSMOS for the participants to use during their development phase.

We will have two tracks in this challenge:

  • Track 1: Real-Time Denoising track for wide band scenario
    The noise suppressor must take less than the stride time Ts (in ms) to process a frame of size T (in ms) on an Intel Core i5 quad-core machine clocked at 2.4 GHz or equivalent processor. For example, Ts = T/2 for 50% overlap between frames. The total algorithmic latency allowed including the frame size T, stride time Ts, and any look ahead must be less than or equal to 40ms. For example, for a real-time system that receives 20ms audio chunks, if you use a frame length of 20ms with a stride of 10ms resulting in an algorithmic latency of 30ms, then you satisfy the latency requirements. If you use a frame of size 32ms with a stride of 16ms resulting in an algorithmic latency of 48ms, then your method does not satisfy the latency requirements as the total algorithmic latency exceeds 40ms. If your frame size plus stride T1=T+Ts is less than 40ms, then you can use up to (40-T1) ms future information.
  • Track 2: Real-Time Denoising track for full band scenario
    Satisfy Track 1 requirements but at 48 kHz.

Participants are forbidden from using the blind test set to retrain or tweak their models. Participants must submit results only if they intend to submit a paper to INTERSPEECH 2021. Failing to adhere to these rules will lead to disqualification from the challenge.


Please send an email to stating that you are interested to participate in the challenge. Please include the following details in your email:

  • List of participants
  • Affiliation of each participant
  • Email ID of each participant

Also, please create a new submission at and fill out all the details. This will help us to easily send out any announcements.


Official rules

These Official Rules (“Rules”) govern the operation of the Microsoft M365 Core INTERSPEECH 2021 Deep Noise Suppression Event Contest (“Contest”). Microsoft Corporation, One Microsoft Way, Redmond, WA, 98052, USA, is the Contest sponsor (“Sponsor”).

In these Rules, “Microsoft”, “we”, “our”, and “us”, refer to Sponsor, and “you” and “yourself” refers to a Contest participant or the parent/legal guardian of any Contest entrant who has not reached the age of majority to contractually obligate themselves in their legal place of residence. “Event” refers to the INTERSPEECH 2021 Deep Noise Suppression event held in Brno, Czechia (the “Event”). By entering you (your parent/legal guardian if you are not the age of majority in your legal place of residence) agree to be bound by these Rules.

The Contest will operate from January 8, 2021 to March 8, 2021 (“Entry Period”). The Entry Period is divided into several periods as described in Section 5 How to Enter.

Open to any registered Event attendee 18 years of age or older. If you are 18 years of age or older but have not reached the age of majority in your legal place of residence, then you must have the consent of a parent/legal guardian. Employees and directors of Microsoft Corporation and its subsidiaries, affiliates, advertising agencies, and Contest Parties are not eligible, nor are persons involved in the execution or administration of this promotion, or the family members of each above (parents, children, siblings, spouse/domestic partners, or individuals residing in the same household). Void in Cuba, Iran, North Korea, Sudan, Syria, Region of Crimea, and where prohibited. For business/tradeshow events: If you are attending the Event in your capacity as an employee, it is your sole responsibility to comply with your employer’s gift policies. Microsoft will not be a party to any disputes or actions related to this matter. PLEASE NOTE: If you are a public sector employee (government and education), all prize awards will be awarded directly to your public sector organization and subject to receipt of a gift letter signed by your agency/institution’s ethics officer, attorney, or designated executive/officer responsible for your organization’s gifts/ethics policy. Microsoft seeks to ensure that by offering items of value at no charge in promotional settings it does not create any violation of the letter or spirit of the entrant’s applicable gifts and ethics rules.

The Contest Objective is to promote collaborative research in real-time single-channel Speech Enhancement aimed to maximize the subjective (perceptual) quality of the enhanced speech. Prizes will be awarded based on the speech quality of deep noise suppression models using the online subjective evaluation framework ITU-T P.835. Only methods described in accepted INTERSPEECH 2021 papers will be eligible for the contest. You may participate as an individual or a team. If forming a team, you must designate a “Team Captain” who will submit all entry materials on behalf of the team. Once you register as part of a Team, you cannot change Teams or alter your current team (either by adding or removing members) after the submission of your Entry. Limit one Entry per person and per team. You may not compete on multiple teams and you may not enter individually and on a team. We are not responsible for Entries that we do not receive for any reason, or for Entries that we receive but are not decipherable or not functional for any reason. Each Team is solely responsible for its own cooperation and teamwork. In no event will Microsoft officiate in any dispute regarding the conduct or cooperation of any Team or its members. The Contest will operate as follows:

Registration / Development Period: January 8, 2021 – March 8, 2021
To register, please send an email to stating that you are interested to participate in the challenge. Please include the following details in your email:

  1. Names of the participants and name of the team captain
  2. Institution/Company
  3. Email

Create a submission by registering at Conference Management Toolkit – 3rd DNS Challenge and fill in all your details. You will be using this tool for final submission and to receive any email announcements from organizers.

Then i. develop a speech enhancement model that best meets the Contest Objective as described in the base paper and ii. submit a paper to INTERSPEECH 2021 which reports the computational complexity of the model in terms of the number of parameters and the time it takes to infer a frame on a particular CPU (preferably Intel Core i5 quad core machine clocked at 2.4 GHz). To develop your model, use any publicly available clean speech and noise datasets, including the contest datasets provided for training and developing models. You may augment your datasets with the contest dataset. You may mix clean speech and noise in any way that improves the performance of your model.

The final evaluation will be conducted on a blind test set that is similar to the open sourced development stage test set. You may use scripts for a baseline noise suppressor that was recently published here. Testing / Entry Period: January 8, 2021 – March 8, 2021. On March 8, the blind test dataset will be released. You will have until 11:59 PM PT on March 15, 2021 to test your model against this dataset and create a set of enhanced clips to submit for judging (your “Entry”) via Conference Management Tool.

You may not use the blind test set to retrain or tweak your model. To submit your entry, submit your processed clips via conference management tool. Each Entry will fall in one of two tracks based on the sampling rate. You must satisfy all the requirements of each track in terms of algorithmic latency. You must also specify the Number of operations per second in your paper submission. INTERSPEECH 2021 Paper Submission and Judging Period: March 15 – 11:59 PM PT June 2, 2021. Your Entry must be described in a paper accepted by INTERSPEECH 2021. To submit a paper, visit Call for Special Sessions & Challenges | INTERSPEECH 2021 and follow instructions to submit a paper.

The entry limit is one per person during the Entry Period. Any attempt by any you to obtain more than the stated number of entries by using multiple/different accounts, identities, registrations, logins, or any other methods will void your entries and you may be disqualified. Use of any automated system to participate is prohibited.

We are not responsible for excess, lost, late, or incomplete entries. If disputed, entries will be deemed submitted by the “authorized account holder” of the email address, social media account, or other method used to enter. The “authorized account holder” is the natural person assigned to an email address by internet or online service provider, or other organization responsible for assigning email addresses.

To be eligible, an entry must meet the following content/technical requirements:

  • Your Entry must be the method described in a paper accepted by INTERSPEECH 2021
  • Your entry must be your own original work; and
  • Your entry cannot have been selected as a winner in any other contest; and
  • You must have obtained any and all consents, approvals, or licenses required for you to submit your entry; and
  • To the extent that entry requires the submission of user-generated content such as software, photos, videos, music, artwork, essays, etc., entrants warrant that their entry is their original work, has not been copied from others without permission or apparent rights, and does not violate the privacy, intellectual property rights, or other rights of any other person or entity. You may include Microsoft trademarks, logos, and designs, for which Microsoft grants you a limited license to use for the sole purposes of submitting an entry into this Contest; and
  • Your entry may NOT contain, as determined by us in our sole and absolute discretion, any content that is obscene or offensive, violent, defamatory, disparaging or illegal, or that promotes alcohol, illegal drugs, tobacco or a particular political agenda, or that communicates messages that may reflect negatively on the goodwill of Microsoft.
  • Your entry must NOT include enhanced clips using other noise suppression methods that you are not submitting to INTERSPEECH 2021.

We are not claiming ownership rights to your Submission. However, by submitting an entry, you grant us an irrevocable, royalty-free, worldwide right and license to use, review, assess, test, and otherwise analyze your entry and all its content in connection with this Contest and use your entry in any media whatsoever now known or later invented for any non-commercial or commercial purpose, including, but not limited to, the marketing, sale or promotion of Microsoft products or services, without further permission from you. You will not receive any compensation or credit for use of your entry, other than what is described in these Official Rules.

By entering you acknowledge that we may have developed or commissioned materials similar or identical to your entry and you waive any claims resulting from any similarities to your entry. Further, you understand that we will not restrict work assignments of representatives who have had access to your entry and you agree that the use of information in our representatives’ unaided memories in the development or deployment of our products or services does not create liability for us under this agreement or copyright or trade secret law.

Your entry may be posted on a public website. We are not responsible for any unauthorized use of your entry by visitors to this website. We are not obligated to use your entry for any purpose, even if it has been selected as a winning entry.

Pending confirmation of eligibility, potential prize winners will be selected by Microsoft or their Agent or a qualified judging panel from among all eligible entries received based on the following judging criteria: 99% – The subjective speech quality evaluated on the blind test set using ITU-T P.835 framework. We will use the submitted clips with no alteration to conduct ITU-T P.835 subjective evaluation and pick the winners based on the results. Among the submitted proposals, if the difference between the models is not statistically significant, the model with a lower number of operations per second be given a higher ranking. 1% – The Entry was described in an accepted INTERSPEECH 2021 paper. Winners will be selected within 7 days following the event. Winners will be notified within 7 days following the Event.

In the event of a tie between any eligible entries, an additional judge will break the tie based on the judging criteria described above. The decisions of the judges are final and binding. If we do not receive enough entries meeting the entry requirements, we may, at our discretion, select fewer winners. If public vote determines winners, it is prohibited for any person to obtain votes by any fraudulent or inappropriate means, including offering prizes or other inducements in exchange for votes, automated programs, or fraudulent IDs. Microsoft will void any questionable votes.

The odds of winning are based on the number and quality of eligible entries received.

To the extent allowed by law, by entering you agree to release and hold harmless Microsoft and its respective parents, partners, subsidiaries, affiliates, employees, and agents from any and all liability or any injury, loss, or damage of any kind arising in connection with this Contest or any prize won.

All local laws apply. The decisions of Microsoft are final and binding.

We reserve the right to cancel, change, or suspend this Contest for any reason, including cheating, technology failure, catastrophe, war, or any other unforeseen or unexpected event that affects the integrity of this Contest, whether human or mechanical. If the integrity of the Contest cannot be restored, we may select winners from among all eligible entries received before we had to cancel, change or suspend the Contest.

If you attempt or we have strong reason to believe that you have compromised the integrity or the legitimate operation of this Contest by cheating, hacking, creating a bot or other automated program, or by committing fraud in any way, we may seek damages from you to the full extent of the law and you may be banned from participation in future Microsoft promotions.

This Contest will be governed by the laws of the State of Washington, and you consent to the exclusive jurisdiction and venue of the courts of the State of Washington for any disputes arising out of this Contest.

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Program timeline

  • January 8, 2021: Release of the datasets and scripts for training and testing
  • March 8, 2021: Blind test set released to participants
  • March 15, 2021: Deadline for participants to submit their results for P.835 subjective evaluation on the blind test set
  • March 22, 2021: Organizers will notify the participants about the results
  • March 26, 2021: Regular paper submission deadline for INTERSPEECH 2021
  • June 2, 2021: Paper acceptance/rejection notification
  • June 4, 2021: Notification of the winners




Track 1 results:

Speech MOS

Track 1 Speech MOS

Background Noise MOS

Track 1 Background Noise MOS

Overall MOS

Track 1 Background Noise MOS

Track 2 Results

Speech MOS

track 2 speech MOS

Background MOS

track 2 Background MOS

Overall MOS

track 2 Overall MOS