Enhanced Audio Features for High- Definition Broadcasts and Discs. Roland Vlaicu Dolby Laboratories, Inc.

Transcription

1 Enhanced Audio Features for High- Definition Broadcasts and Discs Roland Vlaicu Dolby Laboratories, Inc.

2 Entertainment is Changing High definition video Flat panel televisions Plasma LCD DLP New broadcasting technologies MPEG4 video New DVD formats HD-DVD Blu-Ray 2

3 What does this mean for sound? Sound quality is ahead of video with move from stereo to 5.1. but history suggests that more will be expected Home theaters have increasingly diverse speaker configurations not just 5.1 anymore D-cinema will start to increase the number of channels Additional audio programs and enhancements Director commentaries HI / VI services 3

4 An opportunity for audio provided by video A new HD video system means... A new video decoder inside a new set top box or DVD player are required Allowing the possibility to re-examine the choice of audio coding 4

5 Two separate pathways have emerged Broadcasters want lower data rates for audio and video coding more features to match consumer expectation maximize HD content delivery Higher storage capacity of Next Generation Optical Media new opportunities for quality and flexibility of performance 5

6 Two separate pathways have emerged Broadcasters want lower data rates for audio and video coding more features to match consumer expectation maximize HD content delivery Higher storage capacity of Next Generation Optical Media new opportunities for quality and flexibility of performance 6

7 Broadcast audio coding on-air today High quality at low bit rates Mono to 5.1 channels A stereo audio output for legacy TV sets and a digital output (S/PDIF) for 5.1 channels from a home theatre Metadata support to control audio presentation Additional services primarily through additional transmissions Proven interoperability between encoders and decoders Available under reasonable and fair licensing terms 7

8 Broadcast audio coding today High quality at low bit rates - efficiency gains with downmixing 5.1 DD ~576 kbps kbps 5.1 Stereo MPEG1L kbps 384 kbps DD kbps? kbps 5.1 Next gen? kbps 8

9 Broadcast audio coding High quality at low bit rates - efficiency gains with downmixing 5.1 DD ~576 kbps kbps 5.1 Stereo MPEG1L kbps 384 kbps DD kbps 256 kbps 5.1 E-AC3 256 kbps 9

10 Requirements for new audio codecs Improving quality and efficiency Efficiency gains comparable with gains in video Greater flexibility to choose the quality point mono Dolby Digital Plus mono Dolby Digital 32k 64k 384k 640k 3M Bitrate bps 10

11 Requirements for new audio codecs Increased flexibility Ability for higher quality to match higher quality video Ability for more than 5.1 channels in the future mono Dolby Digital Plus mono Dolby Digital 32k 64k 384k 640k 3M Bitrate bps 11

12 Requirements for new audio codecs Integrated support for secondary audio streams Hearing and Visually impaired audio Director s commentary and interactive audio S/PDIF 5.1 DD Main Program 5.1 channels MIX Secondary Program e.g. HI / VI service Downmix Stereo Analog metadata downmix mode 12

13 Requirements for new audio codecs Impact on Consumer products Maintain compatibility with existing home theatres (S/PDIF) Compatibility with future connections (HDMI) Suitable for next gen IC s Set top Box ch AC kbps ch E-AC kbps E-AC3 / AC-3 to AC-3 Converter and Decoder S/PDIF AC ch 2 ch Home Theatre AC-3 decoder 13

14 Connection to A/V Receiver via S/PDIF Set top box AV Receiver S/PDIF connection DOLBY DIGITAL J Audio received as Dolby Digital Plus Output as 5.1-channel Dolby Digital 640 kbps bitstream 14

15 Connection to A/V Receiver via HDMI Set top box AV Receiver HDMI 1.3 connection DOLBY DIGITAL PLUS J Audio received as Dolby Digital Plus Output as encoded bitstream 15

16 Limited change to set top boxes One integrated circuit Decodes Dolby Digital Plus Decodes Dolby Digital Converts Dolby Digital Plus to Dolby Digital for S/PDIF output to interface with all today s home theatre systems 16

17 Requirements for new audio codecs Impact on Production and Transmission Be able to use archive stereo and 5.1 channel material Utilise existing infrastructure and metadata Utilise existing 5.1 AC-3 transmissions 17

18 Broadcast Standardization and use DVB Standardization complete, ETSI TS & TS ATSC Accepted by ATSC S6 for robust channel audio HDTV launches of BSkyB, Canal+, Premiere & ProSiebenSat.1 in Q4/2005 and Q1/

19 Broadcast Standardization and use EICTA EICTA doc EICTA HDTV Minimum Requirements for HD Television Receivers (available from requires future HDTV settop-boxes to support Enhanced AC-3 (=Dolby Digital Plus): 19

20 Broadcast Conclusions 5.1 sound is an important part of HDTV New STB deployments offer opportunity to consider new audio formats Existing SD and HD services already offer 5.1 sound using AC-3 Removing simulcast improves efficiency Future services require greater efficiency, flexibility and support for additional audio services Backwards compatibility with existing home theatres is critical Dolby Digital Plus has been standardised by ETSI, DVB, ATSC to provide these features 20

21 Two separate pathways have emerged Broadcasters want lower data rates for audio and video coding maximize HD content delivery Higher storage capacity of Next Generation Optical Media new opportunities for quality and flexibility of performance 21

22 Dolby Digital Plus in HD Discs Increased flexibility Ability for higher quality to match higher quality video Ability for more than 5.1 channels in the future mono Dolby Digital Plus mono Dolby Digital 32k 64k 384k 640k 3M Bitrate bps 22

23 Summary of audio support in each format Audio Status Codec Status Codec Primary Soundtrack delivery mandatory Dolby Digital Plus DTS (DVD spec) mandatory Dolby Digital DTS (DVD spec) Primary Soundtrack delivery optional DTS HD optional Dolby Digital Plus DTS HD 23

24 Summary of audio support in each format Audio Status Codec Status Codec Primary Soundtrack delivery mandatory Dolby Digital Plus Dolby True HD DTS (DVD spec) mandatory Dolby Digital DTS (DVD spec) Primary Soundtrack delivery optional DTS HD optional Dolby Digital Plus Dolby True HD DTS HD 24

25 Dolby TrueHD Extension to the MLP Lossless codec Audio performance that is Bit-for-Bit identical to studio masters Adds metadata capabilities Up to 18 Mbps and 14 channels if needed in future Supports up to 192 khz sampling rate and 24 bit word length 25

26 Dolby codec bitrates and channels mono Dolby TrueHD mono Dolby Digital Plus mono Dolby Digital 32k 64k 384k 640k 3M 6M 10M 18M Bitrate bps 26

27 HD Disc Conclusions 5.1 sound is an essential part of HD Discs Choice of audio formats Studio master quality audio (lossless) High quality audio that doesn t compete with the picture for bit rate (lossy) More channels, higher quality Support for additional audio services Backwards compatibility with existing home theatres is critical 27

28 Dolby Media Producer Dolby Media Encoder Software encoding on MAC OS X platform DVD-V, DVD-A, HD DVD, Blu-ray Disc Media Dolby Digital Plus, Dolby Digital, Dolby TrueHD, and MLP Accessible locally or by multiple clients via network 28

29 Dolby Media Producer Dolby Media Tools Repair and update files Minimize the need for re-encoding Metadata Editing Timecode Striping File Trimming Concatenation Mac OS X 29

30 Dolby Media Producer Dolby Media Decoder Dolby Digital Plus, Dolby Digital, Dolby TrueHD, and MLP Synchronous file playback with video Monitoring for all consumer listening modes Supports external I/O hardware 30

31 Dolby Media Producer 31

32 Enhanced Audio Features for High- Definition Broadcasts and Discs Roland Vlaicu Dolby Laboratories, Inc.