AuviTran Web Site

Technology

AuviTran is a technology company specialising in the development, design and manufacture of innovative audio and video networking services, solutions and products.
AuviTran solutions and products are based on the following technologies :

• EtherSound: providing very low latency, multi channels audio networking.

• FPGA/VHDL: for flexibility and easy customisation of product

• IP streaming: allowing the distribution, management and control of audio and video streaming over IP.

• Linux system: enabling cost effective and efficient embedded solutions

EtherSound

Audio Distribution over Standard Ethernet: EtherSound enhances established technologies to provide easy-to-implement, high-quality audio networks. The Digigram patented EtherSound protocol provides fully deterministic, very low-latency (125µs plus 1.6µs per additional network node) transmission of synchronized audio channels over standard Ethernet. EtherSound ^TM provides a cost effective fully digital path between a virtually infinite number of networked audio devices with up to 64 channels of 24-bit digital audio at 48 KHz, plus bi-directional status and control data. Off-the-shelf Ethernet components such as 100baseTX switch can be used to extend the number of audio devices, as well as the distance between the devices on the network.

FPGA/VHDL

FPGA for "Field-Programmable Gate Array" is a type of logic chip that can be programmed. An FPGA is similar to a PLD, but whereas PLDs are generally limited to hundreds of gates, FPGAs support thousands to millons of gates. The FPGA-architecture consists of many logic-modules, which are placed in an array-structure. The channels between the logic-modules are used for routing. The array of logic-modules is surrounded by programmable I/O-modules and connected via programmable interconnects. This freedom of routing allows every logic-module to reach every other logic-module or I/O-module. The worldwide first PLD with FPGA-architecture was developed by Xilinx in 1984.

VHDL is an acronym for "Very High speed integrated circuit Hardware Description Language" which is a programming language used to describe a logic circuit by function, data flow behaviour, or structure. VHDL is a programming language: although VHDL was not designed for writing general purpose programs, you can write any algorithm with the VHDL language. If you are able to write programs, you will find in VHDL features similar to those found in procedural languages such as C, Pascal or Ada. VHDL derives most of its syntax and semantics from Ada. Knowing Ada is an advantage for learning VHDL (it is an advantage in general as well). However, VHDL was not designed as a general purpose language but as an HDL (hardware description language). As the name implies, VHDL aims at modeling or documenting electronics systems. Due to the nature of hardware components which are always running, VHDL is a highly concurrent language, built upon an event-based timing model. Like a program written in any other language, a VHDL program can be executed. Since VHDL is used to model designs, the term simulation is often used instead of execution, with the same meaning. Like a program written in another hardware description language, a VHDL program can be transformed with a synthesis tool into a netlist, that is, a detailed gate-level implementation. Design methodologies for programmable components were completly changed when VHDL language appeared. It represents a major interest for design portability and evolutions. Logical synthesis can achieve physical implementation of a design. The whole of the synthetisable VHDL is used, which is a sub-set of the VHDL language. Simulation allows to check the behaviour of a design before or after implementation in the targeted component. Reusability of VHDL designs is important in reducing time-to-market and cost of designs projects. VHDL makes possible reuse of VHDL designs or part of design in a wide range of environment.

Combining FPGA and VHDL offer full flexibility of both Hardware design and programmation when size reduction, performance and cost are targetted.

IP Streaming

Audio and Video transport technology rises every day. AuviTran implements or customizes existing technology (OpenRTSP ShoutCAST , VLC MPlayer) according to customer needs. But AuviTran can also bring knowledge to enhance proprietary protocol and put software a step ahead.

• Broadcast management system have been implemented by AuviTran with Radio France, for automatic broadcast of playlists, real time computation of time-stretching, automatic launch of default playlist in case of loss of signal.

• Streaming technology has been used by AuviTran on several projects. For public address, Announcement system with priority management have been built. Modified RTSP has been implemented on embedded linux streamers and windows broadcaster.

• Video streaming between windows database system and embedded linux have been done for customized application.

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