Browse free open source C# Softphones and projects below. Use the toggles on the left to filter open source C# Softphones by OS, license, language, programming language, and project status.

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  • 1
    OfficeSIP Softphone and Messenger
    OfficeSIP Softphone and Messenger are two enterprise VoIP SIP clients written in C# in .NET Framework. The SIP clients make use of Microsoft UCC API SDK, ensuring the highest quality of audio and video. Compatible with Office Communications Server. See also open source, cross-platform: 1) simple messenger Brief Msg at http://briefmsg.org 2) MUVConf is a multi-user video conferencing, see demo video http://youtu.be/YrBU-Aqtvrk, download https://code.google.com/p/muvconf/downloads/list
    Downloads: 5 This Week
    Last Update:
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  • 2
    SipLine

    SipLine

    Free, native Windows SIP softphone with HD audio, SRTP encryption

    SipLine is a modern, lightweight SIP softphone for Windows 10/11 built with .NET 9 WPF. It provides enterprise-grade VoIP communication with a focus on performance, security, and extensibility. Features Ultra-Fast: Startup in <0.5s, minimal CPU usage HD Audio: Opus and G.711 codecs with adaptive jitter buffer Security: TLS transport, SDES-SRTP encryption, Windows DPAPI credential protection Multi-Account: Up to 5 simultaneous SIP accounts Plugin SDK: C# SDK for custom integrations (CRM, call recording, automation) Plugin Marketplace: Community and premium extensions Headset Support: Jabra, Poly, Sennheiser, Logitech with HID controls Call Quality: Real-time MOS Score, Jitter, Packet Loss and RTT monitoring Enterprise: Silent MSI installer, GPO support, JSON centralized config Compatibility: 3CX, Asterisk, FreePBX, OVH, Twilio, RingCentral, and more Language packages : https://sipline.feelautom.fr/languages
    Downloads: 5 This Week
    Last Update:
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  • 3

    Bria Desktop API Samples

    Samples and wrappers around the Bria desktop API

    The Bria Desktop API has moved to github at https://github.com/CounterPathAPI. Additional samples for Java and Javascript can be found there. The Bria Desktop allows third-party applications to control Bria for Windows softphone clients. By leveraging the Application API, third-party applications can perform commands such as starting an audio or video call, answering a call or placing a call on hold. CounterPath is now encouraging third-party-application developers to integrate their applications with Bria. Suggested applications range from simple functions such as enabling click-to-call from web pages, to integration with sophisticated Call Center, Customer Relationship Management (CRM) and Health Care applications. This project provides sample and convenient wrapper code to utilize this API. *Note* you need a Bria desktop application to utilize the API.
    Downloads: 1 This Week
    Last Update:
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  • 4
    Cisco IP Telephony plugin for creating CiscoXML structure and Push/Pull to/from Cisco IP phone 7XXX and SoftPhone.
    Downloads: 1 This Week
    Last Update:
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  • 5
    Generic Softphone connector for USB Skype Hardware. Would you like to use your skype usb phone with other softphones? this software is for you.
    Downloads: 0 This Week
    Last Update:
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