I'm using the ESP AEC algorithm in Bluetooth HFP (HDP/HFP) voice call scenarios, but I'm experiencing distortion in my voice.

[batuhantsdmr]

Checklist

• Checked the issue tracker for similar issues to ensure this is not a duplicate.
• Provided a clear description of your suggestion.
• Included any relevant context or examples.

Issue or Suggestion Description

I'm using the esp-sr AEC algorithm in a Bluetooth HFP (HDP/HFP) voice call scenario. For HFP, I'm directly using this project:
esp-adf/examples/get-started/pipeline_a2dp_sink_and_hfp/main
/a2dp_sink_and_hfp_example.c

When AEC is enabled, the outgoing audio on the other end is distorted and becomes robotic.

Without AEC, the audio is normal.

To add AEC, I used this document:
https://docs.espressif.com/projects/esp-sr/en/latest/esp32/acoustic_echo_cancellation/README.html
In other words, I used the esp_aec.h file.

Also, my code includes an adaptation I made using the esp-adf/examples/advanced_examples/algorithm/main
/algorithm_examples.c file.

#ifndef DIRECTLY_AEC
This attempts to run in AFE mode, meaning it uses algorithm functions; otherwise, it uses the esp_aec.h APIs. However, AEC doesn't work with algorithm integration. I've attached the relevant code for your review.

Environment:

ESP-IDF version: 5.5.3
ESP-ADF version: 2.8
Device: ESP32 Lyrat Mini V1.2
Sampling rate: 16 kHz

hfp_aec.txt

[sun-xiangyu]

@batuhantsdmr ,
I suggest you switch to the ESP32-S3 or ESP32-S31 chip. We have updated the new AEC algorithm, which now features three modes. However, due to the computational load, it cannot run in real-time on the ESP32 chip. You can refer to the test results in the documentation to see if it meets your requirements.

[batuhantsdmr]

Hello @sun-xiangyu,

I am considering using the ESP32-S31 module in a commercial HMI display product and would appreciate clarification on the following topics:

1. Cyber Resilience Act (CRA)

   • Does the ESP32-S31 support the requirements of the Cyber Resilience Act (CRA)?
   • If CRA support is available, are there any related documents, guidelines, or example implementations available?

2. Wireless Certifications

   • Does the ESP32-S31 module already have the necessary Bluetooth and Wi-Fi certifications?
   • If I integrate the ESP32-S31 module into my own HMI display product, will additional Bluetooth and/or Wi-Fi certifications be required for the final product?

3. Bluetooth Profiles

   • Does the ESP32-S31 support both A2DP and HFP (Hands-Free Profile)?
   • Is there an example project available demonstrating A2DP and HFP functionality?

4. AEC Support

   • Is Acoustic Echo Cancellation (AEC) supported on the ESP32-S31?
   • Are there any plans to provide a combined example project demonstrating HFP + A2DP + AEC working together?

5. Smaller Module Variant

   • We are currently using the ESP32-PICO-MINI module (13.2 × 11.2 × 2.4 mm).
   • The ESP32-S31 module appears to have a minimum size of approximately 18 × 25.5 × 3.1 mm, which is larger than our current solution.
   • Is Espressif planning to release a smaller ESP32-S31-based module (for example, a Mini-sized variant)?
   • If such a module is planned, would it be possible to obtain engineering samples for evaluation?

Thank you for your support.

Best regards,

[sun-xiangyu]

@batuhantsdmr

I am mainly engaged in model deployment and optimization of audio algorithms such as AEC, so the question I can answer is that the ESP32-S31 already supports all the algorithms included in ESP-SR. I don't know the answers to other questions.

As for the progress of Bluetooth and Wi-Fi certifications, you can ask in the ESP-IDF community or directly contact the company's customer support department.