Dolby Laboratories DP569 ユーザーズマニュアル

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Model DP569 User’s Manual 
3-1 
Chapter 3 
 Applications 
The two main applications for the DP569 Dolby Digital encoder are: 
•  Digital Television Broadcasting 
•  DVD Authoring 
Each environment has unique requirements in terms of installation and operation. In 
this chapter, we discuss each application in detail. This chapter assumes the user has 
some knowledge of the ideas and principles behind metadata. If this is not the case, 
we suggest you read Appendix A before continuing. 
3.1 Digital 
Television 
Broadcasting 
3.1.1 
Basic Integration with an MPEG Encoder or Multiplexer 
The DP569 is designed to integrate with existing MPEG encoders and transport 
stream multiplexers. Various methods can be used to control the encoder settings, 
particularly the metadata parameters used during the encoding process, each 
providing a different level of complexity and service. 
The DP569 is connected as shown in Figure 3-1. This diagram shows a 5.1-channel 
installation; stereo and mono installations will be identical except for the number of 
digital audio inputs. 
In the simplest mode of operation, all system settings (including metadata parameters) 
are set once in the encoder for all transmissions. In this mode the metadata settings 
will need to be configured to match the characteristics of the audio currently used 
within the TV station (for example, the levels, dynamic range, peak levels, and so 
forth). Consequently, all audio must conform to these characteristics before it reaches 
the DP569 in order to match these metadata settings. This is similar to the requirements 
of analog or MPEG digital transmissions, where the audio system has fixed 
characteristics and the program audio is conformed to match. 
The next level of complexity uses the GPI status port to select up to four different user 
presets, allowing automation systems to choose different metadata settings for different 
types of programming. For example, one setting for network transmissions and another 
for local insertions, or settings for news, sports, feature films, and commercials. 
Again, the audio will need to be conformed to match the chosen setting; however, 
there is now a greater amount of flexibility available for audio transmissions.