Gateway Codec Negotiation for Circuit-Switched and IP Video Calls
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
When terminals connected to different types of networks, such as circuit-switched and IP networks, the difference in codecs prevents the decoding of compressed streams, leading to an inability to communicate due to the lack of a communication path for control information about the codecs.
Innovation Solution
A converting apparatus and method that converts call control information or decoding information between terminals, using a gateway device with transmitting/receiving units and a control information converter to translate between different codec formats like DCI and SDP, enabling communication even when codec formats differ.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If terminals connected to different types of networks use different codecs, then each terminal can be optimized for its specific network type, but communication between terminals becomes impossible due to incompatible decoding capabilities
Solution Approach 1:
The patent introduces a gateway device as an intermediary between terminals on different networks. The gateway receives control information from one terminal, converts it between different formats (e.g., DCI to SDP), and forwards it to the other terminal. This mediator enables communication between terminals with different codec capabilities without requiring changes to the terminals themselves, thus resolving the contradiction between network adaptability and communication reliability
Solution Approach 2:
The patent changes the format parameters of control information to enable compatibility between different networks. By converting control information between different representation formats (DCI for circuit-switched networks, SDP for IP networks), the system maintains the original terminal designs while enabling cross-network communication through parameter transformation at the gateway level
2Adaptability or versatility
If a gateway device is introduced to convert control information between different formats, then communication between terminals on different networks becomes possible, but the system complexity increases due to additional conversion components
Solution Approach 1:
The gateway device is designed with multi-functional capabilities to handle multiple types of control information formats simultaneously. It can convert between DCI and SDP formats, manage different codec types (H.263, MPEG-4, AMR, G723.1), and support both circuit-switched and IP networks. This universal design consolidates multiple conversion functions into a single device, reducing overall system complexity compared to having separate conversion mechanisms for each format pair
Data Source
AI summary
Picture and speech communication between plural terminals connected to different networks, such as a circuit-switched network and IP network. A converting apparatus 400 for control information or media information for picture/speech communications is provided across first and second terminals 301, 302 connected to respective different types of networks. Converting apparatus 400 includes control information converter 420, transcoder 450 and ability information converter 460. In case the ability information extracted from the decoding information, received from the first terminal 301, is not coincident to the ability information extracted from the call control information received from the second terminal 302, it is further checked whether or not there is picture format size coincidence. If the picture format size coincidence persists in one direction, processing is carried out for converting part of the decoding information or the control information, without causing the operations of the transcoder. In case there is no picture format size coincidence, the transcoder 450 is booted to convert the bitstream.