Meeting Topic: Dolby in High Definition Television (HDTV)
Speaker Name: Adrian Zamudio, Products and Sales Manager, VARI Intl. and Gustavo Matínez, Product Specialist
Meeting Location: Sala de Audio, México D.F.
On this conference we learn about the technology of the transmition of the television in high definition, the standards and the configurations for the audio 5.1.
The terms were:
• Digital Dolby- "Perceptual compression" Compression rate of 13:1 therefore there is loss of information. Format: ac3.
• 5.1- 5 channels with full frequency range, 3 in front and 2 behind, plus one more channel (the .1) with 10 % of the frequency range- around 20 to 120 Hz.
• Metadata- Name given to a group of data that accompanies the audio information; it describes and controls codification and decodification.
• Matrix- Multiple channels (Ltotal and Rtotal) which carry information for a larger number of channels encoded for transmission.
• Discrete Channels- Independent channels, as in a console. Intelligibility.
• Dolby E- Discrete channel "packer" in bundles of up to 8 channels. Medium for professional transport of information.
• Prologic- Decoder. Matrix system.
• Downmixing- Process by which it is ensured that the encoded information can be reproduced by all the systems: Digital Dolby 5.1, surround, stereo or mono. "ONE BITSTREAM FOR ALL"
• Dialogue Normalization- Process by which dialogue level between channels is adjusted.
• Dynamic Range Control- Controls the transmission's dynamic range without compromising audio quality- Lowers level without losing the important bits.
Information for the last 3 (the 3 Ds) is contained in the metadata.