| 1. Dolby E is a digital audio compression technology designed for use by TV broadcast and production professionals in and among their facilities. It allows an AES/EBU (Audio Engineering Society/European Broadcasting Union) audio pair to carry up to eight channels of digital audio and Dolby Digital metadata (see below for information on metadata). Audio can be edited without mutes or clicks and can be encoded and decoded multiple times without audible degradation. |
| 2. With the new DTV systems consumers can now receive 5.1-channel digital audio in their homes via Dolby Digital broadcasts. The problem is that most of the TV broadcast infrastructure can handle only two-channel digital audio. Dolby E provides the networks and cable systems a method for getting 5.1-channel digital audio through their two-channel systems. |
| 3. Dolby E is used in broadcast and post-production facilities to distribute multi-channel (six or eight) audio through a two-channel system. This occurs where there are equipment limitations (the number of tracks on a VTR, for example) or where bandwidth requirements make multi-channel audio costs prohibitive (satellite capacity). Dolby E gets multi-channel audio to TV affiliate stations, so that they can transmit a multi-channel signal to consumers using Dolby Digital. Note that Dolby E audio never reaches the viewer at home. Like all DTV audio, it is decoded to PCM audio and then re-encoded into Dolby Digital just prior to transmission. |
| 4. Dolby Digital is designed for transmission to consumers. It has high bandwidth efficiency and is not optimized for multiple encode/decode cycles or editing. Dolby E allows programs to be decoded, processed and re-encoded many times without degradation as the signal makes its way through the broadcast distribution chain. Audio and video frame rates are the same with Dolby E, enabling precise video picture edits without mutes or glitches. Broadcasters use Dolby E to get the audio to the transmitter; and Dolby Digital to get the audio from the transmitter to consumers. |
| 5. No, Dolby E is not a consumer format. It is only used to transfer multi-channel audio from facility to facility prior to encoding into consumer formats. |
| 6. Real-time decoding is a supported feature of SurCode for Dolby E, but streaming is not supported in this version. You can get real time streaming from our Lawo VST Server plug-in just recently released. Streaming is only available for qualified VST hosts. |
| 7. SurCode for Dolby E introduces the same amount of frame delay that the hardware adds. Dolby E adds one video frame of delay upon encode and one video frame upon decode, which is comparable to the delay introduced by video encode and decode. For example, to go from a video data rate of 1.5 Gb/s to ~300 Mb/s, a Panasonic HD D5 VTR takes one video frame to encode and one video frame to decode. This is the same as Dolby E. Video coders running at 45 Mb/s have longer delays, so the Dolby E system needs to be configured so it can be buffered out appropriately. |
| 8. A Dolby Digital file (AC3) will not be recognized by the encoder as the specification calls for PCM audio, but AC3 meta data can be transferred in the Dolby E stream. However, because Pro Logic II files are stereo PCM files, they can be encoded and transmitted using Dolby E. |
| 9. 8 channels, 24 programs |
| 10.A program is a grouping of audio channels intended for consumer delivery such as stereo, 5.1, or multi-language versions of the same material. A channel is simple the placeholder for an individual audio file. Channels assembled equal the various programs for delivery. |
| 11. 20 bit, 48k |
| 12. Meta data is additional control information that is carried along with the encoded audio program and provides essential information about the audio to a decoder. Meta data provides many important functions including dynamic range control for less-than-ideal listening environments, level matching between programs, down mixing information for the reproduction of multi-channel audio through fewer speaker channels, and other information. Meta data makes Dolby Digital and Dolby E a complete delivery system for audio, rather than just an audio compression system. |
| 13. SurCode for Dolby E Decoder is a fully certified and licensed decoder, identical to the decoding capability of the hardware. However, unless operating on a qualified VST host, this plug-in is a file-based system and does not function as a real-time streaming application. |
| 14. The plug-in is identical in both systems and will operate on both platforms with 1 ilok license. |
| 15. Yes, AWE provides a full transport mechanism with surround sound metering to fully audition and decode the Dolby E stream. |
| 16. While the same license will allow SurCode for Dolby E to operate in both ProTools and AWE, simultaneous use is not allowed. |
| 17. If you have an editor that will do butt-splicing only, editing of a Dolby E stream is possible. However, any manipulation to the Dolby E stream, such as gain adjustments or fades, will damage the stream and prohibit decoding. |
| 18. Dolby E, DDE or WAV file format |
| 19. The Dialogue Normalization (also known as Dialogue Level or Dialnorm) parameter within the Dolby Digital stream provides a relative value to the home decoder or set top box that adjusts the audio to a predetermined replay loudness level. This value aids in level matching between program content and media types (i.e., DVD, DTV, DBS, etc.). Setting the Dialogue Normalization parameter is crucial to the proper operation of home decoders. |
