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1.
What is Dolby E?
2.
Why are TV professionals
looking for a solution
like Dolby E?
3.
Where is Dolby E used?
4.
Why use Dolby E? Why not
use Dolby Digital?
5.
Do I burn Dolby E to disc for my
client?
6.
Does it operate in real time?
7.
What is the plug-in latency or
delay introduced by the plug-in?
8.
Can I send an AC3 or PL
II file as part of a Dolby
E stream?
9.
What is the maximum channel
count for Dolby E?
10.
What is the difference
between a channel and a
program for Dolby E?
11.
What is the maximum resolution
for Dolby E?
12.
What is metadata?
13.
Is this plug-in the same
as the hardware from Dolby?
14.
If Dolby E is available
for AWE, VST, and Pro Tools,
are they the same?
15.
Can I audition my Dolby
E stream in AWE prior to
decoding?
16.
Will 1 license for Dolby
E work in both Pro Tools, VST
and AWE at the same time?
17.
Can I edit a Dolby E stream?
18.
What type-of-file formats
are accepted as a Dolby
E file?
19.
What is Dialog Normalization?
20.
How do I decode Dolby E streams live from tape using an AES/EBU input?
1.
What is Dolby E?
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.
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2.
Why are TV professionals
looking for a solution
like Dolby E?
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.
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3.
Where is Dolby E used?
3.
Dolby E is used in broadcast
and post-production facilities
to distribute multi-channel
audio, six or eight channels,
through a two-channel transport
system. This
occurs where there are equipment
limitations, such as the
number of tracks on a VTR for
example,
or where bandwidth requirements
make multi-channel audio
costs prohibitive such as
with 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.
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4.
Why use Dolby E? Why not
use Dolby Digital?
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.
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5.
Do I burn Dolby E to disc for my
client?
5.
Dolby E is not a consumer
format. It is a professional
format used only to transfer
multi-channel audio
from facility to facility
prior to encoding into consumer
formats.
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6.
Does it operate in real time?
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.
Streaming is only available for
qualified
VST hosts.
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7.
What is the plug-in latency or
delay introduced by the plug-in?
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.
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8.
Can I send an AC3 or PL
II file as part of a Dolby
E stream?
8.
A Dolby Digital or AC3 file
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.
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9.
What is the maximum channel
count for Dolby E?
9.
The maximum channel count is 8
channels and 24 programs.
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10.
What is the difference
between a channel and a
program for Dolby E?
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.
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11.
What is the maximum resolution
for Dolby E?
11.
The maximum essence resolution
is 20 bits at 48 kHz sampling
rate.
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12.
What is metadata?
12.
Metadata is additional control
information that is carried
along with the encoded audio
program and provides essential
information about the audio
to a decoder. Metadata 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. Metadata
makes Dolby Digital and Dolby
E a complete delivery system
for audio, rather than just
an audio compression system.
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13.
Is this plug-in the same
as the hardware from Dolby?
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.
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14.
If Dolby E is available
for AWE, VST and Pro Tools,
are they the same?
14.
The plug–in is identical
in all systems and will
operate on both platforms
with one ilok license.
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15.
Can I audition my Dolby
E stream in AWE prior to
decoding?
15.
Yes, AWE provides a full
transport mechanism with
surround sound metering to
fully audition and decode
the Dolby E stream.
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16.
Will 1 license for Dolby
E work in both Pro Tools, VST
and AWE at the same time?
16.
While the same license will
allow SurCode for Dolby E
to operate in both Pro Tools, VST
and AWE, simultaneous use
is not allowed.
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17.
Can I edit a Dolby E stream?
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.
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18.
What type-of-file formats
are accepted as a Dolby
E file?
18.
File formats are
Dolby E, DDE or WAV.
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19.
What is Dialog Normalization?
19.
The Dialogue Normalization
parameter within the Dolby
Digital stream, also known
as
Dialogue Level
or “dialnorm,” provides
a relative amplitude value
to the decoder or set
top box. Dialogue Normalization
adjusts the audio to a predetermined
replay loudness level. Dialogue
Normalization aids in level
matching between program
content and
media types, such as DVD,
DTV, DBS, et cetera. Setting
the Dialogue
Normalization parameter is
crucial to the proper operation
of Dolby
Digital decoders.
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20.
How do I decode Dolby E streams live from tape using an AES/EBU input?
20.A Dolby E Stream will decode from a track or live input when there is not an encoded file open in the decoder.
Since a Dolby E stream is 2 channels and since the decoder sits on an 8, 6, or 2-channel bus, a structure must be created to bring in 2 channels and connect them into an 8, 6, or 2-channel bus. This is done using the I/O setup in Pro Tools.
First, you need to create a stereo Audio Track and a 7.1 Aux Input. SurCode for Dolby E Decoder is then dropped onto the 7.1 (or 5.1 or stereo) channel mixer strip as an insert. Next you need to go to the I/O Setup and create the bus that will connect a stereo input to a 7.1 bus by creating a sub-path within the 7.1 bus. You will create a 5.1 and stereo subpath in order to link this stereo audio track to a multi-channel Aux input.
So in most cases we have experienced so far, you will be taking the AES output from the device that will be streaming the ENCODED Dolby E stream (be it a HD camera or another audio device/interface etc.) and inputting that into your AES input into the back of your Pro Tools interface.
So choose your inputs accordingly to your AES input on the stereo AUDIO track that we have already made, set the Output of that track to go to your Bus Paths that you have already setup, be it a 7.1, 5.1, or stereo (typically a 7.1 or 5.1 aux track to monitor your decoded audio back into surround). You'll have to make sure that your stereo audio track is Record Enabled so we can pick up that stream. You will then take the decoder and insert it onto your surround AUX track.
*Note, you can insert the plugin onto the stereo audio track, but it is only going to output a decoded Dolby E stream to stereo at this point...making it pointless to setup the surround aux input.
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