From Helix Community
Helix DNA Client Architecture
Architecture documents provide good foundation for undersating Helix DNA Client. More information and guidance on the source code can be obtained by posting to helix-client mailing list.
- Architectural Overviews
- Helix DNA Client Architecture Overview - A broad overview of the Helix DNA Client that shows how the pieces fit together.
- RTSP Session Overview - A broad overview of the process flow for RTSP sessions within the Helix DNA Client.
- Error Reporting Overview - An overview of the error reporting mechanism within the Helix DNA Client, including tips on debugging errors as well as directions on how to add your own error messages to the Helix DNA Client.
- Threading Model - An overview of the Helix DNA Client Threading Model, including a discussion of available threads, thread classes, disabling threads, thread priorities and thread interfaces for plug-ins.
- Logging System - Information & directions on using the Unified Logging system to get logging information from Helix components, as well as directions on how to add logging support to your custom Helix components to leverage the same system for your development efforts.
- Buffering Overview - Description of buffering methods within the Helix DNA Client
- Client State Machine Overview - Description of the different states of the client engine, the transitions between them and the state change notifications. Available in HTML or Word formats.
- Hardware Decoder Integration Guide (PDF Version also available) describes recommended ways to integrate hardware decoding of audio and/or video with the Helix DNA Client media engine. Notes on specific application of above guide to audio and video MDF abstracted hardware decoders on Symbian are also helpful references for similar applications.
- Helix DNA Client Porting project hosts a number of ducuments useful for porting Helix DNA Client but also for understanding cross-platform and platform-specific separation in Helix code base.
- Network Services Overview. This document explains the classes used in the IHXNetServices implementation and how they work together.
- Codec Technical Papers
- Helix MP3 Decoder - Key Features and Specifications for the (very fast) fixed-point Helix MP3 Decoder.
- Helix Optimized HE-AAC Decoder - Key Features and Specifications for the (very fast) fixed-point Helix HE-AAC Decoder.
- RealAudio 8 for Devices - Key Features and Specifications for the fixed-point RealAudio 8 Decoder for devices.
- RealVideo 10/9 Technical Overview (PDF) - Technical summary of the RealVideo 9 Codec, including coding algorithms, performance characteristics and memory usage.
- Client FAQ - Frequently Asked Questions regarding the Helix DNA Client. Contribution of Questions (and Answers) welcome!