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## Project: Flutter WebRTC Real-Time Natural Voice Alteration for Android ### Project Goal Reference Open Source: Flutter Webrctc Repo: [login to view URL] Flutter Webrtc Demo: [login to view URL] I need a developer to select any suitable open-source Flutter WebRTC demo project and modify it to demonstrate real-time sender-side voice alteration. My ultimate goal is to get the modified source code of that open-source Flutter WebRTC project, where the sender’s natural human voice can be altered a little during a WebRTC call. The developer should mainly focus on the **audio alteration part**. Expected flow: Natural Sender Voice → Real-Time Voice Alteration → Altered Natural Human Voice → WebRTC Transmission --- ## Source Code Requirement I will not provide my original application source code. The developer may choose any suitable open-source Flutter WebRTC demo project as the base project. The final delivery should include the modified version of that selected open-source project. --- ## Architecture Requirement The audio alteration should happen on the **sender side before transmission through WebRTC**. Expected technical flow: Microphone → Audio Alteration → WebRTC Encoder → Send Stream Receiver-side processing is not required. --- ## Audio Quality Requirement The altered voice must: * Sound like a natural human speaker but original voice should be altered a little * Remain understandable * Not sound robotic, artificial, broken, or heavily distorted * Work in real time during a WebRTC call * Keep latency acceptable for live conversation --- ## Development Requirement The developer may use any practical approach, including open-source libraries, DSP methods, ML/AI-based methods, or other suitable techniques. AI-assisted development tools may be used if helpful. Final code quality, testing, and debugging remain the developer’s responsibility. --- ## Testing Requirement Testing must be completed at least locally before delivery. The developer must verify that: * The app builds successfully * The app runs on Android * WebRTC communication works * Sender-side audio alteration works * The receiver hears the altered voice * The altered voice sounds natural enough for real-time conversation --- ## Deliverables 1. Modified Flutter WebRTC source code 2. Android APK file 3. Test procedure document explaining: * How to install the APK * How to run the selected WebRTC demo * How to enable/disable voice alteration * How to verify that the receiver hears the altered voice * How local testing was performed 4. Short technical note explaining: * Which open-source project was selected * Where the audio alteration code was added * Any libraries or components used * Any known limitations Note: Example use case where your demo work will be used: We have a Flutter WebRTC-based call center application where customer support agents communicate with customers through voice calls (both party use android app that use flutter webrtc). For privacy reasons, we want the outgoing voice of the support agent to be altered slightly before it is transmitted through WebRTC. --- ## Acceptance Criteria The project will be accepted only if: 1. Modified source code is provided 2. APK installs and runs on Android 3. WebRTC communication works 4. Sender-side voice alteration works during the call 5. Receiver hears the altered voice 6. Altered voice sounds like a natural human voice, not robotic 7. Developer confirms local testing was completed 8. Source code can be rebuilt successfully
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Hello, I will not provide your original application source code. For your project, I suggest using the Flutter WebRTC demo as a base to implement real-time voice alteration. I have experience implementing audio processing in WebRTC applications, specifically using libraries like WebAudio API and DSP techniques to alter audio input dynamically. In a prior project, I integrated a voice modulation feature using a combination of pitch shifting and formant adjustment, maintaining low latency under 50ms to ensure natural-sounding output during calls. For this project, I plan to focus on optimizing the audio alteration process to meet your quality standards while ensuring smooth WebRTC transmission. For the audio alteration, would you prefer using a machine learning-based approach for voice modeling, or should I implement traditional DSP methods to maintain lower latency and higher stability?
$150 USD in 3 days
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103 freelancers are bidding on average $175 USD for this job

Hi there, "♥❤♥ Preferred & Verified by Freelancer staff ♥❤♥" ✔️I am a professional audio engineer with more than 15 years of experience in sound production. I can professionally edit, master, and improve the quality of your audio (podcast, audiobook, voiceover). Do you have audio that needs to be cleaned and repaired? Having clean audio that is clearly understandable is vital for your valuable content. I will also send samples of your own material so you know how your finished product will sound. Please give me information if possible as to the purpose of the audio, for example, it's broadcast, stem, mix, etc) Including Services: ✔ background noise reduction ✔ static noise, hiss, hum, buzz removal ✔ clicks and crackles removal ✔ normalizing the volume of the recording ✔ processing by EQ and compressor ✔ converting your file to any format you like ✔ video sync ✔ Background noise ✔ Reverb and echo reduction ✔ Clicks and pops ✔ Audio clipping ✔ Low-end rumble ✔ Wind noises I will always deliver professional results with efficiency and speed. I have done relevant work like this before as well. Please message me so we can discuss this and proceed accordingly. Please don't hesitate to contact us to see what I can do for you. Regards, BTranslated Professionals Top Ranked Audio Editing Service Provider
$100 USD in 1 day
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Hi, This is a very interesting WebRTC audio-processing project, and I can help you build a practical Android demo where the sender’s voice is subtly altered in real time before WebRTC transmission while still sounding natural and conversational. I understand the key requirement is not “robotic voice effects,” but rather slight privacy-oriented natural voice masking while maintaining clarity and real-time performance. A few technical questions before proceeding: --------------------------------------------------------------------- How strong should the voice alteration be — subtle identity masking or clearly different voice characteristics? Are you open to native Android audio processing (Kotlin/C++) integrated with Flutter if it improves latency and quality? Should the alteration support Bluetooth headsets and speakerphone mode as well? Do you prefer fully offline DSP processing, or are lightweight on-device ML libraries acceptable? What Android minimum SDK version are you targeting? I’m confident this can be implemented cleanly using sender-side audio frame processing within the WebRTC pipeline while keeping latency suitable for real-time conversation. Best regards
$140 USD in 7 days
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Hi There!!! ★★★★ ( Real-time Flutter WebRTC sender-side voice alteration with low-latency DSP integration for natural speech output ) ★★★★ I carefully reviewed your project and understand you need a modified open-source Flutter WebRTC demo where the sender’s microphone audio is processed in real time before transmission. The key focus is adding natural-sounding voice alteration on the sender side without affecting WebRTC communication stability. ⚜ Flutter WebRTC open-source integration & modification ⚜ Sender-side real-time audio processing pipeline ⚜ DSP / audio effects (pitch, tone, subtle modulation) ⚜ Low-latency WebRTC audio stream handling ⚜ Android build, testing & APK generation ⚜ Enable/disable voice alteration controls ⚜ Clean documented modified source code delivery I have experience working with Flutter, WebRTC, and audio stream manipulation where real-time constraints are critical. My approach would be to start from a stable flutter-webrtc demo, then inject an audio processing layer between microphone input and WebRTC encoder using DSP techniques or lightweight audio libraries, ensuring minimal latency and natural voice output. I can also handle full testing on Android, provide APK, and document exactly where changes were made so it stays maintainable and easy to extend. Warm Regards, Farhin B.
$110 USD in 10 days
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Hello, Is your primary focus ensuring the altered voice sounds natural and clear? Do you have a specific open-source Flutter WebRTC demo in mind, or should I choose one? For this project, I'll leverage advanced DSP and AI techniques to achieve realistic, real-time voice alteration before transmission. A key challenge is maintaining audio quality and low latency, which I'll address by selecting optimized libraries and fine-tuning the processing pipeline. I'm eager to start this innovative journey with you. Feel free to send a quick reply, and we can explore the details together!
$30 USD in 1 day
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Hi, Your requirement is very clear, and I can help modify an open source Flutter WebRTC demo to demonstrate sender side real time voice alteration before the audio is transmitted. I have experience with Flutter, Android audio processing, WebRTC media flow, DSP concepts, and real time voice effects. For this project, I would first select a stable Flutter WebRTC demo, confirm Android build and call flow, then add the voice alteration layer between microphone capture and WebRTC transmission so the receiver hears the changed voice during the live call. I would focus on keeping the altered voice natural, understandable, and low latency. Depending on feasibility, I can use a practical DSP based approach first, and evaluate open source ML voice conversion options if they can run reliably in real time on Android. Delivery will include modified source code, APK, testing steps, enable or disable instructions, technical notes, selected project details, and known limitations. Best, Justin
$140 USD in 7 days
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⭐⭐⭐⭐⭐ ✅Hi there, hope you are doing well! I recently worked on a similar Flutter WebRTC project where I implemented real-time audio effects that smoothly altered the sender’s voice before transmission. The key to success in this project lies in seamlessly integrating audio alteration on the sender side without compromising real-time voice quality and latency. Approach: ⭕ Select a robust open-source Flutter WebRTC demo as the base ⭕ Implement and test efficient DSP or AI-based audio alteration on the sender microphone stream ⭕ Ensure the altered voice remains natural and intelligible during live WebRTC calls ⭕ Conduct thorough local testing on Android for build, functionality, and audio quality ⭕ Deliver fully commented modified source code, APK, and comprehensive documentation ❓ Could you please clarify if there are any preferred open-source libraries or audio processing techniques you want me to explore? I am confident in delivering a professional, working prototype that meets your stringent quality and testing requirements and helps you protect agent privacy seamlessly. Best regards, Nam
$200 USD in 3 days
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Hello,how are you? With extensive experience in mobile app and AI development, I am the ideal freelancer to tackle your project. Throughout my 13+ years of Python-Centric experience, I have embarked on numerous high-impact projects, similar to yours, developing tailored solutions. In particular, I have expertise in Web Automation & Scraping, Web3 & Blockchain Development as well as Trading Bot Development which serves as a strong foundation for creating unique and innovative applications reflective of your project. Quality assurance is vital as I’m well aware of its impact on the success of any development project. Hence, I guarantee thorough testing and debugging before delivery to ensure the altered voice is satisfactory and functions flawlessly. By choosing me, you'll have a proficient developer who understands the broader context of your project; capable of delivering not only a modified source code but also an APK file with a detailed test procedure document for seamless application integration.
$40 USD in 1 day
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⭐⭐⭐⭐⭐ Real-Time Voice Alteration in Flutter WebRTC for Android ❇️ Hi My Friend, I hope you're doing well. I've reviewed your project requirements and can see you are looking for a developer to modify a Flutter WebRTC project for real-time voice alteration. You don’t need to look any further; Zohaib is here to help! My team has successfully completed 50+ similar projects in audio processing. I will select a suitable open-source Flutter WebRTC demo and focus on the audio alteration part to meet your needs. ➡️ Why Me? I have 5 years of experience in Flutter development and audio processing, specializing in real-time applications. My skills include working with WebRTC, audio manipulation, and mobile app development. Additionally, I have a strong grip on various relevant technologies to ensure a smooth project execution. ➡️ Let's have a quick chat to discuss your project in detail and let me show you samples of my previous work. Looking forward to discussing this with you! ➡️ Skills & Experience: ✅ Flutter Development ✅ WebRTC Integration ✅ Audio Processing ✅ Real-Time Communication ✅ Mobile App Development ✅ Open-Source Libraries ✅ DSP Techniques ✅ AI/ML Methods ✅ Testing & Debugging ✅ Android Development ✅ Source Code Modification ✅ Technical Documentation Waiting for your response! Best Regards, Zohaib
$150 USD in 2 days
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✋ Hi There!!! ✋ The Goal of the project:- Modify an open-source Flutter WebRTC project to implement real-time sender-side natural voice alteration during live Android calls with low latency and stable WebRTC transmission. I carefully read your complete project description and understand that you need a custom modification of a Flutter WebRTC demo where microphone audio is processed before transmission while maintaining natural voice quality and real-time performance. I am the best fit for this project because I already completed similar Flutter WebRTC and audio processing projects involving real-time audio pipelines, DSP integration, and mobile communication systems. 1. Modify selected Flutter WebRTC open-source project with sender-side audio processing pipeline. 2. Implement real-time voice alteration ensuring natural, human-like output with low latency. 3. Deliver tested Android APK, full source code, and technical documentation with setup instructions. I will provide UI integration, audio processing implementation, WebRTC debugging, testing, and full source code delivery. I have 9+ years experience as a full stack developer and worked on similar real-time communication and audio modification systems successfully. Looking forward to chat with you for make a deal Best Regards Elisha Mariam!
$111 USD in 11 days
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Hi, I can modify a Flutter WebRTC open-source demo to implement real-time sender-side voice alteration with low latency while preserving natural human voice quality during calls. I have experience with Flutter, WebRTC audio pipelines, DSP/audio processing, real-time streaming workflows, and Android audio integration, including modifying microphone streams before WebRTC transmission. Best regards, Shakila Naz
$100 USD in 7 days
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I understand you're looking for a Flutter WebRTC solution for real-time voice alteration, similar to how some advanced communication apps dynamically modify audio streams. My experience with real-time audio processing and WebRTC integration makes me well-equipped to tackle this. My approach will involve leveraging a robust open-source Flutter WebRTC project as a base. For the core audio alteration, I'll explore integrating a lightweight, efficient audio processing library (e.g., using C++ bindings or a Dart-native solution if available) capable of real-time pitch shifting and formant control. The plan is to intercept the audio stream before encoding, apply the chosen alteration algorithm, and then re-encode for transmission. I'll ensure minimal latency to maintain a natural conversational flow. Could you clarify if you have a preference for specific voice alteration algorithms (e.g., pitch shifting, voice cloning, or a combination)? Also, is there a particular target latency you're aiming for? I'm happy to discuss these details further and demonstrate how I can achieve your desired real-time voice alteration.
$198 USD in 21 days
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Hi there, I’m excited about your project on real-time voice alteration using Flutter WebRTC on Android. Having worked extensively with Flutter, WebRTC, and audio DSP, I’m confident I can modify a suitable open-source Flutter WebRTC demo to implement natural sender-side voice alteration that sounds like a different human speaker in real time. I’ll ensure the altered voice is clear, latency remains low, and testing covers all your requirements from APK installation to voice verification. I’ll start by selecting a stable open-source Flutter WebRTC project and integrate an audio processing module capable of natural-sounding real-time voice conversion before the WebRTC encoder. After thorough local testing on Android, I’ll deliver the modified source code, APK, test documentation, and a technical note detailing the implementation, libraries used, and any constraints. Looking forward to starting within a week and completing the project efficiently. Which open-source Flutter WebRTC demo projects have you evaluated or considered for this voice alteration feature? Best regards,
$155 USD in 26 days
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Hi, As an experienced Full-Stack developer proficient in Android and specialized in Flutter, I genuinely believe I'm the best choice for your Real-Time Voice Alteration project. Over the past 15+ years, I've established a proven track record of building robust web and mobile applications, like what's required in this project, enabling me to turn complex requirements into working software effortlessly. I'm confident my extensive skillset with Flutter, as well as my background in AI-enabled tools and their integrations, will be invaluable as we seek to find the most suitable open-source Flutter WebRTC demo project for your needs. Moreover, my knack for problem-solving and my project management abilities guarantee I'll give this task a 100% effort from start to finish. I understand that the main focus here is on the **audio alteration part**, which could involve DSP methods and ML/AI-based techniques, among others. Rest assured, my technical expertise extends to these areas and beyond. From designing databases and implementing secure login flows to developing REST APIs with third-party integrations, I've got you covered on all fronts. Whether it's manipulating audio streams in real-time or optimizing latency for live conversations during WebRTC calls, you can trust me to deliver. Additionally, I offer a comprehensive skillset that goes beyond Flutter mobile development. If needed throughout this project , I can bring my extensive n Thanks!
$75 USD in 3 days
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Hi, I will develop a real-time Flutter WebRTC voice alteration solution by selecting a suitable open-source WebRTC demo project and modifying it to support sender-side audio processing before transmission. The main focus will be integrating a processing layer between the microphone input and the WebRTC audio encoder so that the voice is transformed in real time into a different natural-sounding human voice while maintaining clarity and low latency suitable for live communication. The solution will be implemented using practical DSP or lightweight AI-based voice conversion techniques depending on feasibility, and will be optimized specifically for Android performance. I will thoroughly test the modified application locally to ensure WebRTC calling works properly, the voice alteration is applied in real time, and the receiver hears a natural and understandable altered voice without robotic distortion. Final delivery will include the complete modified Flutter source code, a buildable Android APK, and a clear documentation guide explaining setup, testing steps, enabled features, and technical changes made to the original open-source project.
$150 USD in 4 days
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Hi, happy to jump in on this. I can take a Flutter WebRTC demo and wire in a true sender‑side audio pipeline so your voice is transformed before it ever reaches the encoder. The modification sits between the microphone capture and the WebRTC stream, using a lightweight DSP or small neural voice filter to shift timbre and formants while keeping speech natural and low‑latency. You’ll get the full modified source, an APK, and clear notes on how to enable the altered voice and verify that the receiver hears only the transformed output. This stays clean, stable and rebuildable so you can extend it later.
$140 USD in 7 days
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Hello, I have experience with Flutter, WebRTC, real time audio streaming, and low latency voice processing, and I can modify a suitable open source Flutter WebRTC demo to implement sender side real time voice alteration on Android. The audio pipeline will be handled before WebRTC encoding so the altered voice is transmitted directly to the receiver while maintaining natural speech quality, intelligibility, and low conversational latency. I can integrate lightweight DSP or AI assisted voice processing techniques to subtly alter the speaker’s voice without making it robotic or distorted, and provide a clean implementation with toggle support for enabling or disabling the effect during calls. You will receive the modified Flutter WebRTC source code, Android APK, setup and testing documentation, technical notes about the implementation, and a fully tested local demo confirming that the receiver hears the altered natural voice in real time.
$150 USD in 7 days
4.1
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Hello there, I’ve carefully reviewed your project requirements and have a few important questions to discuss so we can align clearly and start the work smoothly. Could you please connect with me right now so we can discuss the details and move forward? I specialize in mobile app development and have hands-on experience in building scalable, user-friendly, and performance-driven applications for startups and businesses. My core skills include: Android & iOS App Development React Native JavaScript Backend APIs (Node.js / PHP) App Performance & Security App Maintenance & Support I focus on understanding business goals first and then delivering a solution that adds real value to users and drives growth. Thanks for posting this project — looking forward to working with you ? Thanks & Regards, Ishan K.
$140 USD in 7 days
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I can develop a modified Flutter WebRTC Android implementation using a suitable open-source base project, integrating real-time sender-side audio processing so the microphone input is altered before being transmitted through the WebRTC stream. The solution will ensure the altered voice remains natural-sounding, intelligible, and suitable for live conversation with acceptable latency, while maintaining full WebRTC functionality between sender and receiver. Lets connect regards, Shawana
$150 USD in 10 days
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Hello! I am thrilled about the opportunity to work on your project, "Real-Time Voice Alteration in Flutter WebRTC." The challenge of altering the sender's voice in real-time to sound like a different natural speaker during WebRTC calls is both intriguing and exciting. I am eager to dive into the audio alteration aspect of this project and deliver a solution that meets your high-quality standards. Using a combination of open-source libraries, DSP methods, and possibly AI techniques, I will ensure that the altered voice remains clear, natural, and suitable for live conversations. My focus will be on enhancing the sender-side voice alteration process to guarantee a seamless WebRTC transmission. I am committed to thorough testing to ensure the modified source code, Android APK, and voice alteration functionality meet all your requirements. Looking forward to the opportunity to bring this innovative project to life!
$50 USD in 1 day
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Hi [ClientFirstName], I’ve read your project and I’m confident I can build a sender-side real-time voice alteration for Flutter WebRTC. I will base the work on a well-supported open-source Flutter WebRTC demo and extend the audio pipeline before encoding. I plan to implement a low-latency DSP/ML based voice transformation module that runs entirely on the microphone input before WebRTC encoding. This will keep latency acceptable, and I’ll start with a two-week sprint and deliver the modified demo, . Best regards,
$155 USD in 16 days
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