July 23, 2009

Sharing Video IP Cameras with VXI* VoiceXML for 3G-UMTS videocalls and VoIP SIP

We are please to present a new update of the IP Cam Xtras addon for VXI*, one of most interesting feature for 3G/SIP videocalling services is to access to an IP camera. This module allows to code with VoiceXML a hosted video portal to access to many IP cameras in multi-session mode. This mean many users can share any camera connected to the service. 3G videocall’s advantages: No 3G data contrat required (you don’t need Internet plan for your mobile phone) No previous software  application/ SMS instalation required No specific mobile phone setup and configuration, just make a videocall! Video streaming optimized for Mobile Wireless Communication Real-time bidirectional  mode always available Works with all 3G mobile phones (videocall enabled, most of them are today) Works with all 3G UMTS wireless operators Works in roadming mode thru another 3G UMTS operator […]
July 2, 2009

Multimedia Codecs, Compression, and Streaming in 3G-324m

Thanks to Christoph K. for this clear and expert post about 3G videocalling 3G video telephony generally operates over a single 64 kbit/s connection where both parties need to share the available bandwidth. Effectively, the application then is left with 60 kbit/s, or less that are dedicated for both media types, since H.245 call control messages reduce the gross bandwidth. In 3G-324M systems, the bandwidth is allocated dynamically; however, generally said, every party has 50% of the bandwidth available for sending audio and video signals. In a typical unidirectional scenario, 12.2 kbit/s are allocated for the speech codec, and a bitrate of 43-48 kbit/s is allowed for the video data (Sang-Bong, Tae-Jung and Jae-Won). By employing rate control methods in the media encoders, the network can dynamically change these bitrates depending on network conditions and application demand. When two parties […]