Introduction

The LA-5291 provides decoding, encoding, and transcoding to and from PCM and select Dolby® coded formats for up to 16 audio channels in support of real-time immersive Dolby Atmos® workflows. This includes:

  • Decoding Dolby ED2 to PCM

  • Transcoding Dolby ED2 and Dolby E to Dolby Digital Plus and Dolby Digital Plus JOC

  • Encoding PCM to Dolby Digital, Dolby Digital Plus JOC, and Dolby ED2

In the OB truck, the LA-5291 can encode a Dolby Atmos mix into either Dolby ED2 for backhaul to the network center or directly to Dolby Digital Plus JOC for direct transmission to the viewer.

In the broadcast center, it can decode an incoming ED2 stream from the venue and send the PCM audio through the facility for mixing in with studio shows and the playback of interstitials and commercials.

In the air chain, the LA-5291 can encode PCM coming through the plant to Dolby Digital Plus JOC or transcode an incoming ED2 stream directly to Dolby Digital Plus JOC.

Application and Use Cases

Live Dolby® Atmos Creation

In this example, two devices are employed: A Dolby DP590 to author the Atmos-related metadata, and the LA-5291 to encode the Dolby ED2 or Dolby Digital Plus JOC:

  • The DP590 ingests PCM audio over a MADI connection, which can be a combination of stem mixes and objects

  • The DP590 outputs a rendered presentation over MADI for monitoring

  • The DP590 functions may be controlled via the mixing console using GPIO or Ember+, or directly via its web remote UI

  • The DP590 outputs metadata via an IP connection

  • The LA-5291 encodes the content into Dolby ED2 or Dolby Digital Plus JOC.

Figure 1- Live Dolby Atmos creation

Figure 1- Live Dolby Atmos creation

Contribution Encoding

In this example, the Dolby DP590 and LA-5291 work together for contribution encoding:

  • The LA-5291 ingests PCM over MADI or SDI from the DP590, with the metadata being delivered to the LA-5291 via an IP connection

  • The LA-5291 drives the output based on the Vref input

  • The LA-5291 encodes PCM + PMD to Dolby ED2 or Dolby Digital Plus JOC and outputs it via SDI, 2x AES-3, or AES67

Figure 2 - Contribution encoding

Figure 2 - Contribution encoding

Headend Transcoding

In this example, the LA-5291 provides transcoding at the headend:

  • The LA-5291 ingests Dolby ED2, Dolby E, or PCM via Quad-Link 3G SDI, AES67, or Audio/Video over IP (SMPTE ST 2110)

  • The LA-5291 supports a Vref input to drive the output

  • The LA-5291 transcodes Dolby ED2 or Dolby E to Dolby Digital Plus JOC

  • The LA-5291 outputs Dolby Digital Plus JOC over Quad-Link 3G SDI, AES-3, AES67, or Audio/Video over IP

Figure 3- Headed transcoding

Figure 3- Headed transcoding

Headend Contribution Decoding

Here, the LA-5291 ingests a coded stream and decodes it:

  • The LA-5291 ingests a Dolby ED2 stream over Quad-Link 3G SDI, Audio/Video over IP, or AES67

  • The LA-5291 decodes the coded streams and outputs PCM to route through the facility and mix in with studio shows, advertisements and interstitials, etc.

  • The second LA-5291 encodes the PCM signal going to air into the final Dolby Atmos (Dolby Digital Plus JOC) signal

Figure 4 - Headend contribution decoding

Figure 4 - Headend contribution decoding