Dolby Atmos
WHITE PAPER
Dolby® AtmosTM
Next-Generation Audio for Cinema
Overview
Announced in April 2012, Dolby® AtmosTM is quickly becoming the de facto
standard for next-generation sound in the cinema, as major studio directors,
sound teams, and exhibitors adopt the solution. Because Dolby Atmos delivers an
audio experience beyond anything available to date, addressing the limitations
to creating truly immersive and lifelike audio that were inherent in earlier audio
platforms, professionals from all disciplines within the cinema industry are
embracing this technology.
'ROE\�$WPRV�DGGV�WKH�ÁH[LELOLW\�DQG�SRZHU�RI�G\QDPLF�DXGLR�REMHFWV�LQWR�WUDGLWLRQDO�FKDQQHO�EDVHG�ZRUNÁRZV��7KHVH�DXGLR�REMHFWV�DOORZ�PRYLHPDNHUV�WR�FRQWURO�GLVFUHWH�VRXQG�HOHPHQWV�LUUHVSHFWLYH�RI�VSHFLÀF�SOD\EDFN�VSHDNHU�FRQÀJXUDWLRQV��LQFOXGLQJ�RYHUKHDG�VSHDNHUV��'ROE\�$WPRV�DOVR�LQWURGXFHV�QHZ�HűFLHQFLHV�WR�WKH�SRVWSURGXFWLRQ�SURFHVV��DOORZLQJ�VRXQG�PL[HUV�WR�HűFLHQWO\�capture their creative intent and then, in real-time, monitor or automatically
JHQHUDWH�'ROE\�6XUURXQG�����DQG�����YHUVLRQV��'ROE\�$WPRV�VLPSOLÀHV�GLVWULEXWLRQ³WKH�DXGLR�HVVHQFH�DQG�DUWLVWLF�LQWHQW�LV�DOO�FRQWDLQHG�LQ�D�WUDFN�ÀOH�ZLWKLQ�WKH�'LJLWDO�Cinema Package (DCP), which can be faithfully played back in a broad range of
WKHDWUH�FRQÀJXUDWLRQV�
Content creators welcome the new power they have to tell their stories with Dolby
$WPRV��6WXGLRV�DSSUHFLDWH�WKH�VLPSOLÀHG�GLVWULEXWLRQ��([KLELWRUV�DUH�DEOH�WR�RŲHU�audiences a new, compelling, only-in-a-theatre experience. The audience can now
enjoy a completely new listening experience with enveloping sound that brings the
stories on screen more fully to life.
2 Dolby Atmos
Table of Contents
1 Introduction ......................................................................................................................... 3
1.1 A Brief History of Film Sound ............................................................................. 3
1.2 The Introduction of Digital Cinema ................................................................... 4
1.3 Working Toward the Next Generation of Cinema Sound ............................. 5
2 Dolby Atmos Overview ...................................................................................................... 6
2.1 Audience Immersion ............................................................................................. 6
2.1.1 Overhead Sound........................................................................................ 6
2.1.2 Improved Surround Definition and Audio/Visual Coherence ........ 7
2.1.3 Improved Audio Quality and Timbre Matching .................................. 8
2.2 Author Once, Optimize Everywhere.................................................................. 8
2.2.1 Capturing the Creative Intent ................................................................ 8
2.2.2 Optimizing During Rendering ................................................................ 9
2.3 Workflow Integration ..........................................................................................11
2.3.1 In the Dubbing Theater .........................................................................11
2.3.2 During Packaging ....................................................................................12
2.3.3 For Distribution .......................................................................................12
2.3.4 In the Cinema ...........................................................................................12
3 Audio Postproduction and Mastering .........................................................................12
3.1 Production Sound ................................................................................................13
3.2 Editing and Premixing ........................................................................................13
3.2.1 Dialogue ....................................................................................................13
3.2.2 Foley and Effects ....................................................................................13
3.2.3 Music ..........................................................................................................13
3.3 Final Mixing............................................................................................................13
3.4 Mastering ...............................................................................................................14
4 Digital Cinema Packaging and Distribution ...............................................................15
4.1 Audio File Delivery ...............................................................................................15
4.2 Appending Audio Tracks ....................................................................................16
4.3 Track File Encryption ..........................................................................................16
4.4 Digital Cinema Package Distribution ..............................................................16
5 Theatrical Exhibition ........................................................................................................17
5.1 Equipment Considerations ................................................................................17
5.1.1 Dolby Atmos Cinema Processor CP850 .............................................17
5.1.2 Integration with Cinema Servers .......................................................17
5.2 Auditorium Considerations ...............................................................................17
5.2.1 Optimized Playback ................................................................................18
5.2.2 Screen Speakers .....................................................................................19
5.2.3 Surround Speakers ................................................................................20
5.3 Dolby Atmos Commissioning Service .............................................................23
3Dolby Atmos
1 Introduction
1.1 A Brief History of Film Sound
6LQFH�WKH�LQWURGXFWLRQ�RI�VRXQG�ZLWK�ÀOP�LQ�������WKHUH�KDV�EHHQ�D�VWHDG\�HYROXWLRQ�of technology used to capture the artistic intent of the motion picture soundtrack
and to replay it in a cinema environment.
,Q�WKH�����V��V\QF�VRXQG�RQ�GLVF�JDYH�ZD\�WR�YDULDEOH�DUHD�VRXQG�RQ�ÀOP��ZKLFK�ZDV�IXUWKHU�LPSURYHG�LQ�WKH�����V�ZLWK�WKHDWULFDO�DFRXVWLF�FRQVLGHUDWLRQV�DQG�improved speaker design, along with the introduction of multitrack recording and
VWHHUDEOH�UHSOD\��XVLQJ�FRQWURO�WRQHV�WR�PRYH�VRXQGV���,Q�WKH�����V�DQG�����V��PDJQHWLF�VWULSLQJ�RI�ÀOP�DOORZHG�PXOWLFKDQQHO�SOD\EDFN�LQ�WKHDWUHV��LQWURGXFLQJ�VXUURXQG�FKDQQHOV�DQG�XS�WR�ÀYH�VFUHHQ�FKDQQHOV�LQ�SUHPLXP�YHQXHV�
,Q�WKH�����V��'ROE\�LQWURGXFHG�QRLVH�UHGXFWLRQ��ERWK�LQ�SRVWSURGXFWLRQ�DQG�RQ�ÀOP��DORQJ�ZLWK�D�FRVW�HŲHFWLYH�PHDQV�RI�HQFRGLQJ�DQG�GLVWULEXWLQJ�PL[HV�ZLWK�WKUHH�screen channels and a mono surround channel, as shown in Figure 1.1. The quality
RI�FLQHPD�VRXQG�ZDV�IXUWKHU�LPSURYHG�LQ�WKH�����V�ZLWK�'ROE\�65�QRLVH�UHGXFWLRQ�DQG�FHUWLÀFDWLRQ�SURJUDPV�VXFK�DV�7+;®.
Projector
Sound
Processor
Power
Amps
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
L - Left
R - Right
C - Center
OBE - Optional subwoofer
S - Surround
Key
S
Screen L
OBE
C
R
Figure 1.1 Dolby Surround
4 Dolby Atmos
7KH�����V�VDZ�WKH�ODXQFK�RI�GLJLWDO�VRXQG�WR�WKH�FLQHPD��DOORZLQJ�����PL[LQJ��PDVWHULQJ��DQG�SOD\EDFN�SURYLGLQJ�GLVFUHWH�/HIW��&HQWHU��DQG�5LJKW�VFUHHQ�FKDQQHOV��/HIW�DQG�5LJKW�6XUURXQG�DUUD\V��DQG�D�VXEZRRIHU�FKDQQHO�IRU�ORZ�IUHTXHQF\�HŲHFWV��as shown in Figure 1.2. The surround channels were able to provide a wider
frequency response, since the band-limiting of matrix surrounds (for prevention of
“bleed” or crosstalk from the screen channels) was no longer required. The screen
FKDQQHOV�ZHUH�H[SDQGHG�WR�LQFOXGH�ÀYH�VFUHHQ�VSHDNHUV�ZLWK�WKH�UHLQWURGXFWLRQ�of “inner left” and “inner right” channels, and were further enhanced with Dolby
'LJLWDO�6XUURXQG�(;���DGGLQJ�D�%DFN�6XUURXQG�FKDQQHO��$OO�'ROE\�'LJLWDO�ÀOP�SULQWV�FRQWLQXH�WR�FRQWDLQ�D�'ROE\�65�DQDORJ�WUDFN�IRU�FRPSDWLELOLW\�LQ�DOO�WKHDWUHV�(including those with only mono capabilities).
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
Projector
Sound
Processor
Power
Amps
menu mute
format
01 04 05 10
11 U1 U2 NS
OK
CP650
Digital Cinema Processor
Format 10Dolby Digital
M1 0 7.0P1
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
L - Left
R - Right
C - Center
LFE - Low-Frequency Effects
Ls - Left Surround
Rs - Right Surround
Key
Screen
L
LFE
C
R
Ls
Rs
Figure 1.2 Dolby Digital
1.2 The Introduction of Digital Cinema
The introduction of digital cinema provided the opportunity for the industry to
HYROYH�EH\RQG�WKH�WHFKQLFDO�OLPLWDWLRQV�LQ�SODFH�ZLWK�VRXQG�RQ�ÀOP��:LWK�WKH�FUHDWLRQ�RI�VWDQGDUGV�IRU�GLJLWDO�FLQHPD�����FKDQQHOV�RI�DXGLR�KDYH�EHHQ�PDGH�available within a DCP to allow for greater creativity for content creators and a
more enveloping and realistic auditory experience for cinemagoers. During the
advent of digital cinema, the industry focused primarily on the development of
technologies and standards relating to image and security. At the same time, the
industry has enjoyed the ability to use existing 5.1-equipped dubbing theaters and
FLQHPDV�IRU�WKH�FUHDWLRQ�DQG�SOD\EDFN�RI�VRXQGWUDFNV�XVLQJ�HŲHFWLYHO\�WKH�VDPH�FRQWHQW�IRU�ERWK�GLJLWDO�FLQHPD�DQG����PP�SOD\EDFN�
,Q�������WKH�ÀUVW�VWHS�LQ�HQKDQFLQJ�GLJLWDO�FLQHPD�VRXQG�ZDV�XQGHUWDNHQ�ZLWK�WKH�introduction of Dolby Surround 7.1. This format continues the pattern of increasing
WKH�QXPEHU�RI�VXUURXQG�FKDQQHOV�E\�VSOLWWLQJ�WKH�H[LVWLQJ�/HIW�DQG�5LJKW�6XUURXQG�FKDQQHOV�LQWR�IRXU�´]RQHV�µ�VKRZQ�LQ�)LJXUH������7KH�LQFUHDVHG�DELOLW\�IRU�VRXQG�designers and mixers to control the positioning of audio elements in the theatre,
along with improved panning from screen to surrounds, has made the format a
5Dolby Atmos
success in both the rapid adoption by content creators and the speed of conversion
RI�WKHDWUHV��:LWK�PRUH�WKDQ�����WLWOHV�DQG�������VFUHHQV�HTXLSSHG�LQ�OHVV�WKDQ�WKUHH�years since its launch, the success of Dolby Surround 7.1 has indicated a desire
within the motion picture industry to embrace new audio technologies.
Screen
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
Projector
Sound
Processor
Power
Amps
menu mute
format
01 04 05 10
11 U1 U2 NS
OK
CP650
Digital Cinema Processor
Format 10Dolby Digital
M1 0 7.0P1
1 2
3
4 5 6
7 8 1
2
3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
1 2
3
4 5 6
7 8 1
2
3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
1 2
3
4 5 6
7 8 1
2 3
4 5 6
7 8
Light One Light Two Light Three
Dial One Dial Two
Power Setting
for dial one
Power Setting
for dial two
On
Off
L
Lss
LFE
C
R
Lrs
RrsRss
L - Left
R - Right
C - Center
LFE - Low-Frequency Effects
Lss - Left side surround
Rss - Right side surround
Lrs - Left rear surround
Rrs - Right rear surround
Key
Figure 1.3 Dolby Surround 7.1
1.3 Working Toward the Next Generation of Cinema Sound
Throughout the development of Dolby Surround 7.1, Dolby continued to
investigate the future of cinema sound, working toward a new audio format. Dolby
HTXLSSHG�GXEELQJ�WKHDWHUV�ZLWK�YDULRXV�VSHDNHU�FRQÀJXUDWLRQV�WR�GHWHUPLQH�ZKLFK�VSHDNHU�ORFDWLRQV�DUH�FRPSHOOLQJ�WR�D�FRQWHQW�FUHDWRU��5HPL[HG�PRYLH�FRQWHQW�ZDV�WDNHQ�LQWR�GLŲHUHQW�DXGLWRULD�LQ�YDULRXV�FRXQWULHV��HTXLSSHG�ZLWK�DSSURSULDWH�VSHDNHU�ORFDWLRQV��WR�GHWHUPLQH�ZKDW�LV�HŲHFWLYH�LQ�WKHDWUHV�RI�YDU\LQJ�size and shape. Finally, these tests were demonstrated to global exhibitors to gain
their feedback on what would work for their customers and what they would be
willing and able to install.
This cycle of research, along with Dolby’s cinema product and technology footprint,
has allowed precise targeting of requirements for the next generation of digital
cinema sound, in areas from sound design and editing to rerecording, mastering,
packaging, distribution, and replay in theatres. For example, although many
FLQHPDV�DUH�HTXLSSHG�ZLWK�LQQHU�OHIW��/F��DQG�LQQHU�ULJKW��5F��UHSOD\�FKDQQHOV��WKHVH�FKDQQHOV�DUH�UDUHO\�XVHG�EHFDXVH�D�GHGLFDWHG�ÀYH�VFUHHQ�FKDQQHO�PL[�PXVW�EH�FUHDWHG�WR�VXSSRUW�WKHP��+RZHYHU��RQ�ODUJHU�VFUHHQV��DGGLWLRQDO�FKDQQHOV�FRXOG�provide both smoother pans and more accurate placement of sound to match the
image. Similarly, while the use of surround arrays can arguably create a suitably
DPELHQW�HŲHFW�ZLWK�DSSURSULDWH�FRQWHQW��WKH�LQWURGXFWLRQ�RI�'ROE\�6XUURXQG�����GHPRQVWUDWHG�WKDW�VLJQLÀFDQW�LPSURYHPHQW�LQ�ORFDOL]DWLRQ�RI�VRXQG�UHVXOWV�IURP�increasing the number of surround zones within the auditorium.
6 Dolby Atmos
In parallel to research into a new audio format, Dolby revisited critical areas of the
theatrical replay environment, including the technology and standards by which
dubbing theaters and cinemas are aligned and monitored. Introduction of a new
audio format allows changes to be implemented without breaking compatibility,
making it an ideal opportunity to revisit existing standards. In some areas the
FXUUHQW�SUDFWLFH�LV�UDWLÀHG��DQG�LQ�RWKHUV�LW�LV�LPSURYHG�XSRQ�DV�WHFKQRORJ\�HYROYHV��
This exhaustive research, along with lessons learned from decades of introducing
new cinema sound formats, culminated in Dolby’s 2012 introduction of Dolby
Atmos as the next generation of sound for cinema. The Dolby Atmos platform
HQFRPSDVVHV�SURGXFWV��VHUYLFHV��DQG�WHFKQRORJLHV�WKDW�EXLOG�RQ�H[LVWLQJ�ZRUNÁRZV�and technologies to deliver an audio experience well beyond the best available
to date.
2 Dolby Atmos Overview
Dolby Atmos achieves unprecedented levels of audience immersion and engagement
E\�RŲHULQJ�SRZHUIXO�QHZ�DXWKRULQJ�WRROV�WR�PL[HUV��,W�DOVR�RŲHUV�D�QHZ�FLQHPD�SURFHVVRU�IHDWXULQJ�D�ÁH[LEOH�UHQGHULQJ�HQJLQH�WKDW�RSWLPL]HV�WKH�DXGLR�TXDOLW\�DQG�VXUURXQG�HŲHFWV�RI�WKH�'ROE\�$WPRV�VRXQGWUDFN�WR�HDFK�URRP·V�VSHDNHU�OD\RXW�and characteristics. In addition, Dolby Atmos has been designed from the ground
up to maintain backward compatibility and minimize the impact on the current
SURGXFWLRQ�DQG�GLVWULEXWLRQ�ZRUNÁRZV�
2.1 Audience Immersion
7ZR�FULWLFDO�HOHPHQWV�VLJQLÀFDQWO\�LPSURYH�WKH�DXGLHQFH�H[SHULHQFH�RYHU�����DQG�7.1 systems:
�� Sounds originating overhead
�� Sounds originating from discrete sources throughout the auditorium
2.1.1 Overhead Sound
In the real world, sounds originate from all directions, not from a single horizontal
plane. An added sense of realism can be achieved if sound can be heard from
overhead, from the “upper hemisphere.”
7KH�ÀUVW�H[DPSOH�LV�RI�D�VWDWLF�RYHUKHDG�VRXQG��VXFK�DV�DQ�LQVHFW�FKLUSLQJ�LQ�D�WUHH�in a jungle scene. In this case, placing that sound overhead can subtly immerse the
audience in the scene without distracting from the action on the screen.
Another example is a somewhat less-subtle helicopter elevating on the screen and
Á\LQJ�RŲ�RYHU�WKH�DXGLHQFH��7KH�XVH�RI�PRUH�GLVFUHWH�VXUURXQG�]RQHV��DV�LQ�'ROE\�Surround 7.1, helps achieve the perception of overhead movement, but adding
overhead speakers prevents the brain from having to construct a phantom image of
the helicopter moving overhead.
7Dolby Atmos
2.1.2 Improved Surround Definition and Audio/Visual Coherence
For many years, cinema has enjoyed having discrete screen channels in the form of
/HIW��&HQWHU��5LJKW��DQG�RFFDVLRQDOO\�LQQHU�OHIW�DQG�LQQHU�ULJKW�FKDQQHOV��7KHVH�GLVFUHWH�VRXUFHV�KDYH�VXűFLHQW�IUHTXHQF\�UHVSRQVH�DQG�SRZHU�KDQGOLQJ�WR�DOORZ�VRXQGV�WR�EH�DFFXUDWHO\�SODFHG�LQ�GLŲHUHQW�DUHDV�RI�WKH�VFUHHQ��DQG�WR�SHUPLW�WLPEUH�PDWFKLQJ�DV�sounds are moved or panned between locations.
In a 5.1 setup, the surround zones comprise an array of speakers, all of which carry
WKH�VDPH�DXGLR�LQIRUPDWLRQ�ZLWKLQ�HDFK�/HIW�6XUURXQG�RU�5LJKW�6XUURXQG�]RQH��6XFK�DUUD\V�DUH�SDUWLFXODUO\�HŲHFWLYH�ZLWK�DPELHQW�RU�GLŲXVH�VXUURXQG�HŲHFWV�
+RZHYHU��LQ�HYHU\GD\�OLIH�PDQ\�VRXQGV�RULJLQDWH�IURP�UDQGRPO\�SODFHG�SRLQW�VRXUFHV��Consider the example of being in a restaurant. In addition to ambient music apparently
EHLQJ�SOD\HG�IURP�DOO�DURXQG��VXEWOH�EXW�GLVFUHWH�VRXQGV�RULJLQDWH�IURP�VSHFLÀF�SRLQWV��a person chatting from one point, the clatter of a knife on a plate from another. Being
able to place such sounds discretely around the auditorium can add a heightened sense
of realism without being obvious.
$�OHVV�VXEWOH�H[DPSOH�LV�WKH�VRXQG�RI�D�JXQVKRW�ÀUHG�IURP�VRPHZKHUH�EHKLQG�WKH�audience. In this case, the intention may be to momentarily distract the viewer from
the screen, as might happen if somebody were to hear such a sound in real life. Being
DEOH�WR�SLQSRLQW�WKLV�VRXQG�FRXOG�EH�PRUH�HŲHFWLYH�WKDQ�WU\LQJ�WR�HPXODWH�LW�WKURXJK�DQ�DUUD\�RI�VSHDNHUV��7KH�LQFUHDVHG�UHVROXWLRQ�RI�VXUURXQG�VSHDNHU�FRQÀJXUDWLRQ�SURYLGHG�E\�'ROE\�6XUURXQG�����KHOSV�DGG�UHDOLVP�WR�VXFK�HŲHFWV��EXW�WKH�DELOLW\�WR�individually address surround speakers in addition to the 7.1 arrays takes realism to a
new level.
A fundamental role of cinema sound is to support the story on the screen. Dolby Atmos
VXSSRUWV�PXOWLSOH�VFUHHQ�FKDQQHOV��UHVXOWLQJ�LQ�LQFUHDVHG�GHÀQLWLRQ�DQG�LPSURYHG�audio/visual coherence for onscreen sounds or dialogue. The ability to precisely
position sources anywhere in the surround zones also improves the audio/visual
transition from screen to room. If a character on the screen looks inside the room
toward a sound source, the mixer has the ability to precisely position the sound so that
LW�PDWFKHV�WKH�FKDUDFWHU·V�OLQH�RI�VLJKW��DQG�WKH�HŲHFW�ZLOO�EH�FRQVLVWHQW�WKURXJKRXW�the audience (Figure 2.1, right). In contrast, in a traditional 5.1 or Dolby Surround
����PL[��WKH�HŲHFW�ZRXOG�EH�GHSHQGHQW�RQ�D�YLHZHU·V�VHDWLQJ�SRVLWLRQ��VHH�)LJXUH�2.1, left). Increased surround resolution creates new opportunities to use sound in
a room-centric way. This approach is an important innovation, quite distinct from
the traditional approach in which content is created assuming a single listener at the
´VZHHW�VSRW�µ�5RRP�FHQWULF�DXGLR�EHWWHU�VXSSRUWV�WKH�RQVFUHHQ�DFWLRQ�
8 Dolby Atmos
Figure 2.1 Benefits of Increased Surround Resolution for Audio/Visual Coherence
2.1.3 Improved Audio Quality and Timbre Matching
,Q�DGGLWLRQ�WR�WKH�VSDWLDO�EHQHÀWV��WKH�'ROE\�$WPRV�FRUH�DXGLR�TXDOLW\�LV�DQ�improvement over existing state-of-the-art multichannel systems.
The timbral quality of some sounds, such as steam hissing out of a broken pipe, can
VXŲHU�IURP�EHLQJ�UHSURGXFHG�E\�DQ�DUUD\�RI�VSHDNHUV��7KH�DELOLW\�WR�GLUHFW�VSHFLÀF�sounds to a single speaker gives the mixer the opportunity to eliminate the artifacts
of array reproduction and deliver a more realistic experience to the audience.
Traditionally, surround speakers do not support the same full-range frequency
UHVSRQVH�DQG�OHYHO�ZKHQ�FRPSDUHG�WR�WKH�VFUHHQ�FKDQQHOV��+LVWRULFDOO\��WKLV�KDV�created issues for mixers, reducing their ability to freely move full-range sounds
from screen to room. As a result, theatre owners have not felt compelled to upgrade
WKHLU�VXUURXQG�FKDQQHO�FRQÀJXUDWLRQ��FUHDWLQJ�D�FKLFNHQ�DQG�HJJ�GLOHPPD�WKDW�KDV�prevented the widespread adoption of higher-quality installations.
'ROE\�$WPRV�LPSURYHV�WKH�DXGLR�TXDOLW\�LQ�GLŲHUHQW�URRPV�WKURXJK�VXFK�EHQHÀWV�DV�improved room equalization and surround bass management, so that the speakers
�ZKHWKHU�RQ��RU�RŲVFUHHQ��FDQ�EH�IUHHO\�DGGUHVVHG�E\�WKH�PL[HU�ZLWKRXW�FRQFHUQ�about timbral matching.
2.2 Author Once, Optimize Everywhere
2.2.1 Capturing the Creative Intent
In order to accurately place sounds around the auditorium, the sound designer or
mixer needs more control. Providing this control involves changing how content is
designed, mixed, and played back through the use of audio objects and positional data.
Audio objects can be considered as groups of sound elements that share the same
physical location in the auditorium. Objects can be static or they can move. They
are controlled by metadata that, among other things, details the position of the
VRXQG�DW�D�JLYHQ�SRLQW�LQ�WLPH��:KHQ�REMHFWV�DUH�PRQLWRUHG�RU�SOD\HG�EDFN�LQ�D�theatre, they are rendered according to the positional metadata using the speakers
that are present, rather than necessarily being output to a physical channel.
9Dolby Atmos
Thinking about audio objects is a shift in mentality compared with how audio is
currently prepared, but it aligns well with how audio workstations function. A track in
a session can be an audio object, and standard panning data is analogous to positional
PHWDGDWD��,Q�WKLV�ZD\��FRQWHQW�SODFHG�RQ�WKH�VFUHHQ�PLJKW�SDQ�LQ�HŲHFWLYHO\�WKH�same way as with channel-based content, but content placed in the surrounds can be
rendered to an individual speaker if desired.
:KLOH�WKH�XVH�RI�DXGLR�REMHFWV�SURYLGHV�GHVLUHG�FRQWURO�IRU�GLVFUHWH�HŲHFWV��RWKHU�DVSHFWV�RI�D�PRYLH�VRXQGWUDFN�GR�ZRUN�HŲHFWLYHO\�LQ�D�FKDQQHO�EDVHG�HQYLURQPHQW��)RU�H[DPSOH��PDQ\�DPELHQW�HŲHFWV�RU�UHYHUEHUDWLRQV�DFWXDOO\�EHQHÀW�IURP�EHLQJ�IHG�WR�DUUD\V�RI�VSHDNHUV��$OWKRXJK�WKHVH�FRXOG�EH�WUHDWHG�DV�REMHFWV�ZLWK�VXűFLHQW�ZLGWK�WR�ÀOO�DQ�DUUD\��LW�LV�EHQHÀFLDO�WR�UHWDLQ�VRPH�FKDQQHO�EDVHG�IXQFWLRQDOLW\�
Dolby Atmos therefore supports “beds” in addition to audio objects. Beds are
HŲHFWLYHO\�FKDQQHO�EDVHG�VXEPL[HV�RU�VWHPV��7KHVH�FDQ�EH�GHOLYHUHG�IRU�ÀQDO�SOD\EDFN�(rendering) either individually or combined into a single bed, depending on the
GHVLUH�RI�WKH�FRQWHQW�FUHDWRU��7KHVH�EHGV�FDQ�EH�FUHDWHG�LQ�GLŲHUHQW�FKDQQHO�EDVHG�FRQÀJXUDWLRQV�VXFK�DV�����������RU�HYHQ�IXWXUH�IRUPDWV�VXFK�DV������LQFOXGLQJ�DUUD\V�RI�overhead speakers).
Figure 2.2 Object and Bed Combination
2.2.2 Optimizing During Rendering
'ROE\�$WPRV�DOORZV�XS�WR�����WUDFNV�WR�EH�SDFNDJHG��XVXDOO\�D�FRPELQDWLRQ�RI�EHGV�and objects. The renderer takes these audio tracks and processes the content according
WR�WKH�VLJQDO�W\SH��%HGV�DUH�IHG�WR�DUUD\V��ZKLFK�SRWHQWLDOO\�UHTXLUH�GLŲHUHQW�GHOD\V�and equalization processing than individual objects. The process supports rendering of
WKHVH�EHGV�DQG�REMHFWV�WR�XS�WR����VSHDNHU�RXWSXWV�
up to
64
speaker
feeds
out
up to
128
tracks
in
Dolby
Atmos
Level
manager
Beds
Objects
Rendering
Array
correction
B-chain
processing
per speaker
Figure 2.3 Block Diagram of Dolby Atmos Rendering
10 Dolby Atmos
The rendering algorithm intelligently uses the surround speakers in the theatre to
WKHLU�EHVW�HŲHFW��%\�LPSURYLQJ�WKH�SRZHU�KDQGOLQJ�DQG�IUHTXHQF\�UHVSRQVH�RI�WKH�surround speakers, and by keeping the same monitoring reference level for each
output channel or speaker in the theatre, objects being panned between screen and
surround speakers can maintain their sound pressure level (SPL) and have a closer
timbre match without, importantly, increasing the overall SPL in the theatre.
$Q�DUUD\�RI�DSSURSULDWHO\�VSHFLÀHG�VXUURXQG�VSHDNHUV�KDV�HQRXJK�KHDGURRP�WR�reproduce the maximum dynamic range available within a Dolby Surround 7.1 or
����VRXQGWUDFN�����G%�DERYH�UHIHUHQFH�OHYHO���+RZHYHU��LW�LV�XQOLNHO\�WKDW�D�VLQJOH�surround speaker will have the same headroom as a large multiway screen speaker.
$V�D�UHVXOW��WKHUH�DUH�LQVWDQFHV�ZKHQ�DQ�REMHFW�SODFHG�LQ�WKH�VXUURXQG�ÀHOG�UHTXLUHV�a sound pressure greater than that attainable using a single surround speaker.
In these cases, the renderer spreads the sound across an appropriate number of
VSHDNHUV�LQ�RUGHU�WR�DFKLHYH�WKH�UHTXLUHG�63/��:LWK�'ROE\�$WPRV��LPSURYLQJ�WKH�quality and power handling of surround speakers provides an improvement in the
faithfulness of the rendering.
Additionally, the support for bass management of the surround speakers through
the installation of optional rear subwoofers allows each surround speaker to
achieve improved power handling and potentially use smaller cabinets.
Finally, the addition of side surround speakers closer to the screen than has been
the practice for previous formats ensures that objects can smoothly transition from
screen to surround. It is important to note that these additional side surround
speakers are not used to replay content destined for a surround array (for instance,
in Dolby Surround 7.1 rendered output, or in a 5.1 bed as part of a Dolby Atmos
mix) since this will compromise the experience of using a sidewall array.
More information on speaker layout recommendations is available in Section 5,
7KHDWULFDO�([KLELWLRQ�
11Dolby Atmos
2.3 Workflow Integration
'ROE\�$WPRV�WHFKQRORJ\�LQWHJUDWHV�LQWR�H[LVWLQJ�SRVWSURGXFWLRQ�ZRUNÁRZV�ZLWKRXW�adding excessive time and cost to the process.
Creation
Audio
workstation/
Mixing console
Dolby
system
Dolby
Atmos
Dolby
Atmos
Dolby theater
(KDM per title)
Standard theater
(KDM per format)
DCP
Standard
5.1 or
7.1 Mix
5.1 Mix
7.1 Mix
Packaging Exhibition
Figure 2.4 Cinema Audio Workflow
2.3.1 In the Dubbing Theater
The hybrid model of beds and objects allows most sound design, editing, premixing,
DQG�ÀQDO�PL[LQJ�WR�EH�SHUIRUPHG�LQ�WKH�VDPH�PDQQHU�DV�WKH\�KDYH�EHHQ�LQ� previous formats.
Plug-in applications for digital audio workstations allow existing panning
techniques within sound design and editing to remain unchanged. In this way, it is
possible to lay down both beds and objects within the workstation in 5.1-equipped
editing rooms.
Object audio and metadata are recorded in the session in preparation for the pre-
DQG�ÀQDO�PL[�VWDJHV�LQ�WKH�GXEELQJ�WKHDWHU�
Metadata is integrated into the dubbing theater’s console surface, allowing the
channel strips’ faders, panning, and audio processing to work with both beds or
stems and audio objects. The metadata can be edited using either the console
surface or the workstation user interface, and the sound is monitored using a Dolby
5HQGHULQJ�DQG�0DVWHULQJ�8QLW��508��
The bed and object audio data and associated metadata are recorded during the
mastering session to create a “print master,” which includes a Dolby Atmos mix
and any other rendered deliverables (such as a Dolby Surround 7.1 or 5.1 theatrical
PL[���7KLV�SULQW�PDVWHU�ÀOH�LV�ZUDSSHG�XVLQJ�LQGXVWU\�VWDQGDUG�0DWHULDO�([FKDQJH�)RUPDW��0;)��ZUDSSLQJ�WHFKQLTXHV��DQG�GHOLYHUHG�WR�WKH�GLJLWDO�FLQHPD�SDFNDJLQJ�IDFLOLW\�XVLQJ�VWDQGDUG�'&3�WHFKQLTXHV�WKDW�DOORZ�ÀOH�YDOLGDWLRQ�SULRU�WR�SDFNDJLQJ�
12 Dolby Atmos
2.3.2 During Packaging
7KH�'ROE\�$WPRV�SULQW�PDVWHU�ÀOHV�FRQWDLQ�D�'ROE\�$WPRV�PL[��DORQJ�ZLWK�D�standard, channel-based main audio mix. The main audio mix can be rendered by
WKH�508�LQ�WKH�GXEELQJ�WKHDWHU��RU�FUHDWHG�E\�D�VHSDUDWH�PL[�SDVV�LI�GHVLUHG��7KH�PDLQ�DXGLR�PL[�IRUPV�WKH�VWDQGDUG�PDLQ�DXGLR�WUDFN�ÀOH�ZLWKLQ�WKH�'&3��DQG�WKH�'ROE\�$WPRV�PL[�IRUPV�DQ�DGGLWLRQDO�WUDFN�ÀOH��6XFK�D�WUDFN�ÀOH�LV�VXSSRUWHG�E\�existing industry standards, and is ignored by DCI-compliant servers that cannot
use it.
2.3.3 For Distribution
The Dolby Atmos packaging scheme allows delivery of a single DCP to any cinema,
whether or not it is equipped to decode and play back a Dolby Atmos soundtrack.
7KH�FRPSRVLWLRQ�FRQWDLQV�ERWK�PDLQ�DXGLR�DQG�'ROE\�$WPRV�WUDFN�ÀOHV��$�VLQJOH�key delivery message (KDM) targeted to the cinema’s media block enables
controlled playback of the content, and a DCI-compliant server with any cinema
sound processor is able to play the composition.
2.3.4 In the Cinema
7KH�'&3�FRQWDLQLQJ�D�'ROE\�$WPRV�WUDFN�ÀOH�LV�UHFRJQL]HG�E\�DOO�VHUYHUV�DV�D�YDOLG�package, and ingested accordingly. In theatres with Dolby Atmos, the Dolby Atmos
WUDFN�ÀOH�LV�LQJHVWHG�LQWR�WKH�VHUYHU�DQG�GXULQJ�SOD\EDFN�LV�VWUHDPHG�WR�WKH�'ROE\�$WPRV�FLQHPD�SURFHVVRU�IRU�UHQGHULQJ��+DYLQJ�ERWK�'ROE\�6XUURXQG������RU������and Dolby Atmos audio streams available, the Dolby Atmos cinema processor can
switch between them if necessary. This switching is analogous to the Dolby Digital
DQG�'ROE\�65�WUDFNV�RQ����PP�SULQWV��ZKHUHE\�D�V\VWHP�WKDW�LV�HTXLSSHG�IRU�'ROE\�Digital replay will do so from a single inventory print, but a system that cannot
use the Dolby Digital track (or one that encounters a print or hardware issue) will
VHDPOHVVO\�UHYHUW�WR�WKH�'ROE\�65�WUDFN�WR�NHHS�WKH�VKRZ�UXQQLQJ�
3 Audio Postproduction and Mastering
&RQVLGHU�WKH�ZRUNÁRZ�LQ�DXGLR�SRVWSURGXFWLRQ³WKHUH�DUH�PDQ\�VWHSV��VRPH�RI�ZKLFK�RFFXU�LQ�SDUDOOHO��WKDW�OHDG�WR�WKH�FUHDWLRQ�RI�D�ÀQDO�PL[��7KUHH�PDLQ�FDWHJRULHV�RI�VRXQG�DUH�XVHG�LQ�D�PRYLH�PL[��GLDORJXH��PXVLF��DQG�HŲHFWV�
(ŲHFWV�FRQVLVW�RI�JURXSV�RI�VRXQGV�VXFK�DV�DPELHQW�QRLVH��YHKLFOHV��RU�FKLUSLQJ�ELUGV³HYHU\WKLQJ�WKDW�LV�QRW�GLDORJXH�RU�PXVLF��6RXQG�HŲHFWV�FDQ�EH�UHFRUGHG�RU�V\QWKHVL]HG�E\�WKH�VRXQG�GHVLJQHU�RU�FDQ�RULJLQDWH�IURP�HŲHFWV�OLEUDULHV��$�VXEJURXS�RI�HŲHFWV�NQRZQ�DV�)ROH\��VXFK�DV�IRRWVWHSV�DQG�GRRU�VODPV��DUH�performed by Foley actors.
'ROE\�VRXQG�FRQVXOWDQWV�ZRUN�JOREDOO\�RQ�DOO�ÀOP�VRXQGWUDFNV�XVLQJ�'ROE\�technologies, and continue to provide services in all aspects of the audio post
ZRUNÁRZ��7KH�IROORZLQJ�VHFWLRQV�RXWOLQH�LQLWLDO�LQWHJUDWLRQ�RI�'ROE\�$WPRV�LQWR�D�IHDWXUH�ÀOP�
13Dolby Atmos
3.1 Production Sound
6RXQG�LV�UHFRUGHG�RQ�VHW��DQG�KXQGUHGV�RI�VRXQG�ÀOHV�DUH�FUHDWHG��6SRWWLQJ�VHVVLRQV�GHWHUPLQH�ZKLFK�ÀOHV��LQFOXGLQJ�GLDORJXH�RU�)ROH\�FRQWHQW��DUH�RI�acceptable quality.
3.2 Editing and Premixing
3.2.1 Dialogue
3URGXFWLRQ�GLDORJXH�WKDW�LV�QRW�FRQVLGHUHG�XVDEOH�LV�UHUHFRUGHG�LQ�$'5��DXWRPDWHG�dialogue replacement or additional dialogue recording) sessions. The dialogue
HGLWRU�XVHV�ERWK�SURGXFWLRQ�GLDORJXH�DQG�$'5��DQG�WKH�GLDORJXH�PL[HU�FUHDWHV�dialogue premixes containing mono dialogue tracks and several channel-based
beds of “loop group,” such as crowd noise. At this point, dialogue that would
EHQHÀW�IURP�EHLQJ�SODFHG�RU�SDQQHG�WKURXJKRXW�WKH�DXGLWRULXP�LV�PDUNHG�DV�DQ�object and panned accordingly.
3.2.2 Foley and Effects
7KH�)ROH\�HGLWRU�WDNHV�SURGXFWLRQ�DQG�UHFRUGHG�HŲHFWV�WR�FUHDWH�VHYHUDO�FKDQQHO�EDVHG�EHGV�RI�)ROH\��$Q\�)ROH\�WKDW�ZRXOG�EHQHÀW�IURP�EHLQJ�SODFHG�SUHFLVHO\�LQ�the auditorium would be marked and panned as an object.
7KH�HŲHFWV�HGLWRU�WDNHV�GHVLJQHG�DQG�OLEUDU\�VRXQG�HŲHFWV�WR�FUHDWH�ZKDW�FRXOG�EH�KXQGUHGV�RI�VRXQG�HŲHFWV�HOHPHQWV�DQG�EHGV�RI�DPELHQFHV��7KH�HŲHFWV�PL[HU�WDNHV�WKHVH�VHVVLRQV��DORQJ�ZLWK�WKH�)ROH\�FRQWHQW��WR�FUHDWH�HŲHFWV�SUHPL[HV�RI�ERWK�LQGLYLGXDO�WUDFNV�DQG�FKDQQHO�EDVHG�EHGV��$JDLQ��DQ\�VXLWDEOH�HŲHFWV�DUH�LGHQWLÀHG�and positioned as objects.
(ŲHFWV�PD\�EH�IXUWKHU�VSOLW�LQWR�JURXSV�VXFK�DV�DWPRVSKHUHV��FURZGV��DQG�movements, such as rustling cloth.
3.2.3 Music
Music is mixed by a scoring mixer and passed to the music editor and music mixer
for creation of music premixes, which can again consist of tracks and channel-
based beds. The use of full-range surround speakers allows mixers to move music
RŲVFUHHQ�WR�WKH�VXUURXQG�]RQHV�DQG�PDLQWDLQ�WKH�VDPH�WLPEUH�DQG�ÀGHOLW\�DV�WKH�screen speakers.
Mixers have also found that assigning music tracks as objects and moving the
REMHFWV�RŲVFUHHQ�ZLOO�FKDQJH�WKH�SHUFHSWLRQ�RI�WKH�PXVLF�VL]H�DQG�FDQ�HQKDQFH�WKH�DXGLHQFH·V�VHQVH�RI�HQYHORSPHQW��$GGLWLRQDOO\��PRYLQJ�PXVLF�RŲVFUHHQ�IUHHV�XS�WKH�VFUHHQ�VSHDNHUV�IRU�DXGLR�HŲHFWV�DQG�FDQ�KHOS�FODULI\�GLDORJXH�WUDFNV�
3.3 Final Mixing
$OO�RI�WKH�PXVLF��GLDORJXH��DQG�HŲHFWV�DUH�EURXJKW�WRJHWKHU�LQ�WKH�GXEELQJ�WKHDWHU�GXULQJ�WKH�ÀQDO�PL[��DQG�WKH�UHUHFRUGLQJ�PL[HU�V��XVH�WKH�SUHPL[HV��DOVR�NQRZQ�as the “mix minus”) along with the individual sound objects and positional data to
FUHDWH�VWHPV�DV�D�ZD\�RI�JURXSLQJ��IRU�H[DPSOH��GLDORJXH��PXVLF��HŲHFWV��)ROH\��DQG�
14 Dolby Atmos
EDFNJURXQG��,Q�DGGLWLRQ�WR�IRUPLQJ�WKH�ÀQDO�PL[��WKH�PXVLF�DQG�HŲHFWV�VWHPV�DUH�used as a basis for creating dubbed foreign-language versions of the movie.
(DFK�VWHP�FRQVLVWV�RI�D�FKDQQHO�EDVHG�EHG�DQG�VHYHUDO�DXGLR�REMHFWV�ZLWK�PHWDGDWD��6WHPV�FRPELQH�WR�IRUP�WKH�ÀQDO�PL[��8VLQJ�REMHFW�SDQQLQJ�LQIRUPDWLRQ�IURP�ERWK�WKH�DXGLR�ZRUNVWDWLRQ�DQG�WKH�PL[LQJ�FRQVROH��WKH�508�UHQGHUV�WKH�DXGLR�WR�the speaker locations in the dubbing theater. This rendering allows the mixers to
hear how the channel-based beds and audio objects combine, and also provides
WKH�DELOLW\�WR�UHQGHU�WR�GLŲHUHQW�FRQÀJXUDWLRQV��7KH�PL[HU�FDQ�XVH�FRQGLWLRQDO�PHWDGDWD��ZKLFK�GHIDXOWV�WR�UHOHYDQW�SURÀOHV��WR�FRQWURO�KRZ�WKH�FRQWHQW�LV�UHQGHUHG�to, for example, Dolby Surround 7.1. In this way, the mixers retain complete control
of how the movie plays back in all the scalable environments that Dolby Atmos
allows.
3.4 Mastering
During the mastering session, the stems, objects, and metadata are brought
WRJHWKHU�LQ�D�'ROE\�$WPRV�SDFNDJH�WKDW�LV�VLJQHG�RŲ�LQ�WKH�GXEELQJ�WKHDWHU�DQG�remains untouched through to exhibition in the cinema. The Dolby Atmos package
contains the backward-compatible Dolby Surround 7.1 or 5.1 theatrical mix.
7KH�508�FDQ�UHQGHU�WKLV�RXWSXW�LI�GHVLUHG��WKHUHE\�HOLPLQDWLQJ�WKH�QHHG�IRU�DQ\�DGGLWLRQDO�ZRUNÁRZ�VWHSV�LQ�JHQHUDWLQJ�H[LVWLQJ�FKDQQHO�EDVHG�GHOLYHUDEOHV��7KH�DXGLR�ÀOHV�DUH�SDFNDJHG�XVLQJ�LQGXVWU\�VWDQGDUG�0;)�ZUDSSLQJ�WHFKQLTXHV�WR�minimize the risk of changes, and delivered to the digital cinema packaging facility.
As has been standard practice for several decades, the dubbing theater is equipped
and calibrated by Dolby sound consultants in exactly the same manner as the
SOD\EDFN�WKHDWUHV�WR�HQVXUH�FRPSOHWH�FRQÀGHQFH�WKDW�ZKDW�LV�FUHDWHG�LQ�WKH�VWXGLR�will translate predictably to the cinema.
In addition to rendering channel-based theatrical deliverables, the Dolby
$WPRV�PDVWHU�ÀOH�FDQ�EH�XVHG�WR�JHQHUDWH�RWKHU�GHOLYHUDEOHV�VXFK�DV�FRQVXPHU�PXOWLFKDQQHO�RU�VWHUHR�PL[HV��$JDLQ��LQWHOOLJHQW�SURÀOHV�DQG�FRQGLWLRQDO�PHWDGDWD�LQ�'ROE\�$WPRV�DOORZ�FRQWUROOHG�UHQGHULQJV�WKDW�FDQ�VLJQLÀFDQWO\�UHGXFH�WKH�WLPH�required to create such mixes.
15Dolby Atmos
Dolby Atmos
Print MasterFinal MixRe-recording
Objects
Stems
Objects
BedsDialogue
Foley
Music
Effects
Crowd
atmo-
spheres,
moves
Render/
Mastering
5.1/7.1/9.1 Beds/Stems
Objects
Render/
Monitoring
Native
:
5.1 Mix
7.1 Mix
Dolby Atmos rendered mix
Channel-based mix
Lt/Rt
9.1 channel
7.1 channel
5.1 channel
Render/
Monitoring
Native
:
9.1 channel
7.1 channel
5.1 channel
Figure 3.1 Dolby Atmos Audio Post Workflow
4 Digital Cinema Packaging and Distribution
4.1 Audio File Delivery
7KH�'ROE\�$WPRV�DXGLR�ÀOHV�GHOLYHUHG�WR�WKH�SDFNDJLQJ�IDFLOLW\�FDQ�EH�LPSRUWHG�LQWR�an appropriate digital cinema packaging system, such as the Dolby Secure Content
&UHDWRU��6&&�������WR�FUHDWH�D�'&3��7KH�DXGLR�WUDFN�ÀOHV�PD\�EH�ORFNHG�WRJHWKHU�WR�KHOS�SUHYHQW�V\QFKURQL]DWLRQ�HUURUV�ZLWK�WKH�'ROE\�$WPRV�WUDFN�ÀOH�WKDW�KDV�EHHQ�VLJQHG�RŲ�LQ�WKH�GXEELQJ�WKHDWHU��7KH�6&&�����FDQ�DOVR�UHVSRQG�WR�GDWD�LQ�WKH�SULQW�PDVWHU�ÀOH��VXFK�DV�ÀUVW�IUDPH�DQG�ODVW�IUDPH�RI�DFWLRQ��WR�HQVXUH�DFFXUDWH�V\QFKURQL]DWLRQ�RI�VRXQG�WR�SLFWXUH�DV�ZDV�VLJQHG�RŲ�LQ�WKH�GXEELQJ�WKHDWHU�
8SRQ�LPSRUWLQJ��WKH�0;)�DXGLR�ÀOHV��ERWK�'ROE\�$WPRV�DQG�PDLQ�DXGLR��DUH�FKHFNHG�WR�FRQÀUP�WKDW�WKHUH�LV�QR�FRUUXSWLRQ�RU�WDPSHULQJ��,I�DQ�HUURU�LV�UHSRUWHG��WKH�RSHUDWRU�ZLOO�EH�DOHUWHG�WR�WDNH�DSSURSULDWH�DFWLRQ��7KLV�ZRUNÁRZ�LV�VLPLODU�WR�successful practice used in Dolby Digital mastering for theatrical releases, whereby
WKH�'ROE\�'LJLWDO�DQG�'ROE\�65�WUDFNV�DUH�SK\VLFDOO\�DVVRFLDWHG�DQG�DOVR�FRGHG�WR�prevent unauthorized tampering.
16 Dolby Atmos
4.2 Appending Audio Tracks
&HUWDLQ�WHUULWRULHV�UHTXLUH�WKH�DGGLWLRQ�RI�WUDFN�ÀOHV�GXULQJ�WKH�SDFNDJLQJ�SKDVH��VXFK�DV�WKH�DGGLWLRQ�RI�KHDULQJ�LPSDLUHG��+,��RU�YLVXDOO\�LPSDLUHG�QDUUDWLRQ��9,�1��WUDFNV�WR�WKH�PDLQ�DXGLR�WUDFN�ÀOH��7KH�6&&�����DOORZV�WKH�DGGLWLRQ�RI�WUDFNV�WR�WKH�PDLQ�DXGLR�WUDFN�ÀOH�ZKHUH�UHTXLUHG�E\�WKH�LQGXVWU\�
4.3 Track File Encryption
8SRQ�FUHDWLRQ�RI�WKH�'&3��WKH�PDLQ�DXGLR�0;)�ÀOH��ZLWK�DSSURSULDWH�DGGLWLRQDO�WUDFNV�DSSHQGHG��LV�HQFU\SWHG�XVLQJ�6037(�VSHFLÀFDWLRQV�LQ�DFFRUGDQFH�ZLWK�H[LVWLQJ�SUDFWLFH��7KH�'ROE\�$WPRV�0;)�LV�SDFNDJHG�DV�DQ�DX[LOLDU\�WUDFN�ÀOH��DQG�LV�RSWLRQDOO\�HQFU\SWHG�XVLQJ�D�V\PPHWULF�FRQWHQW�NH\�SHU�WKH�6037(�VSHFLÀFDWLRQ�
Dolby
Atmos
audio
files
5.1 / 7.1
audio
files
DCPWrapping /
Encryption
JPEG 2000
Compression
DCP
Packaging
Distribution
KDM
From dubbing theater
Subtitle
files
Image
files
Figure 4.1 Digital Cinema Packaging Workflow
4.4 Digital Cinema Package Distribution
This single DCP can be delivered to any DCI-compliant server. Any installations
WKDW�DUH�QRW�VXLWDEO\�HTXLSSHG�VLPSO\�LJQRUH�WKH�DGGLWLRQDO�WUDFN�ÀOH�FRQWDLQLQJ�WKH�'ROE\�$WPRV�VRXQGWUDFN�DQG�XVH�WKH�H[LVWLQJ�PDLQ�DXGLR�WUDFN�ÀOH�IRU�VWDQGDUG�playback. Those installations equipped with a Dolby Atmos Cinema Processor
&3����DUH�DEOH�WR�LQJHVW�DQG�UHSOD\�WKH�'ROE\�$WPRV�VRXQGWUDFN�ZKHUH�DSSOLFDEOH��reverting to the standard audio track as necessary.
17Dolby Atmos
5 Theatrical Exhibition
This section provides information on installation of Dolby Atmos systems in theatres.
5.1 Equipment Considerations
5.1.1 Dolby Atmos Cinema Processor CP850
'ROE\�$WPRV�DQG�WKH�'ROE\�$WPRV�&LQHPD�3URFHVVRU�&3����FKDQJH�KRZ�WKHDWUH�VSHDNHUV�DUH�LQVWDOOHG��FDOLEUDWHG��DQG�PDLQWDLQHG��:LWK�WKH�LQWURGXFWLRQ�RI�PDQ\�more potential speaker outputs, each individually equalized and balanced, there
LV�D�QHHG�IRU�LQWHOOLJHQW�DQG�WLPH�HűFLHQW�DXWRPDWLF�URRP�HTXDOL]DWLRQ��&RXSOHG�with the ability to manually adjust any automated room equalization, it is critical
WKDW�WKH�TXDOLÀHG�LQVWDOOHU�NQRZ�H[DFWO\�ZKDW�SURFHVVLQJ�LV�EHLQJ�DSSOLHG�WR�D�JLYHQ�VSHDNHU�FKDQQHO�LQ�RUGHU�WR�PDNH�HGXFDWHG�GHFLVLRQV�ZKHQ�ÀQH�WXQLQJ�D�WKHDWUH�
In addition to the implementation of reliable automatic equalization, Dolby Atmos
uses a sophisticated ȟ/ȺƆ-RFWDYH��UDWKHU�WKDQ�WKH�VWDQGDUG�����RFWDYH��EDQG�equalization engine derived from the successful Dolby Lake®�SURFHVVRU��8S�WR����outputs can be processed to more accurately balance the sound in theatre. The
system also allows scheduled monitoring of the individual speaker outputs, from
cinema processor output right through to the sound reproduced in the auditorium.
Local or network alerts can be created to ensure that appropriate action is taken. In
WKH�PHDQWLPH��WKH�ÁH[LEOH�UHQGHULQJ�V\VWHP�PD\�DXWRPDWLFDOO\�UHPRYH�D�GDPDJHG�VSHDNHU�RU�DPSOLÀHU�IURP�WKH�UHSOD\�FKDLQ�DQG�UHQGHU�DURXQG�LW��DOORZLQJ�WKH�VKRZ�to continue.
5.1.2 Integration with Cinema Servers
7KH�'ROE\�$WPRV�&LQHPD�3URFHVVRU�&3����LV�FRQQHFWHG�WR�WKH�GLJLWDO�FLQHPD�VHUYHU�ZLWK�WKH�H[LVWLQJ���ï�$(6�PDLQ�DXGLR�FRQQHFWLRQ�DQG�DQ�(WKHUQHW�FRQQHFWLRQ�IRU�streaming Dolby Atmos audio data. Playback of Dolby Surround 7.1 or 5.1 content
XVHV�WKH�H[LVWLQJ�$(6�DXGLR�FRQQHFWLRQ��'ROE\�$WPRV�DXGLR�GDWD�LV�VWUHDPHG�RYHU�(WKHUQHW�WR�WKH�FLQHPD�SURFHVVRU�IRU�GHFRGLQJ�DQG�UHQGHULQJ��DQG�FRPPXQLFDWLRQ�EHWZHHQ�WKH�VHUYHU�DQG�WKH�FLQHPD�SURFHVVRU�DOORZV�WKH�DXGLR�WR�EH�LGHQWLÀHG�DQG�synchronized. In the event of any issue with the Dolby Atmos track playback, sound
is reverted back to Dolby Surround 7.1 or 5.1 PCM audio.
5.2 Auditorium Considerations
:KLOH�ÁH[LELOLW\�WR�VLPSOLI\�WKH�LQWURGXFWLRQ�RI�QHZ�WHFKQRORJ\�LV�D�FULWLFDO�IDFWRU�LQ�WKH�UHOHDVH�RI�D�QHZ�DXGLR�IRUPDW��WKLV�VDPH�ÁH[LELOLW\�PXVW�EH�XVHG�WR�DOORZ�the system to scale and evolve with the industry. Prior to the introduction of Dolby
Atmos and continuing today, we have seen 5.1 cinema sound transition to Dolby
Surround 7.1, and other exhibitors have installed even more channel-based speaker
V\VWHPV�LQFOXGLQJ������������������DQG�EH\RQG�
18 Dolby Atmos
Dolby provides recommendations on speaker layout for use with Dolby Atmos
soundtracks, as detailed in this document, but the Dolby Atmos system is designed
to allow both content creators and exhibitors to decide how they want to use it. A
PL[HU�FDQ�OLVWHQ�WR�DQG�GHWHUPLQH�KRZ�FRQWHQW�LV�JRLQJ�WR�EH�UHQGHUHG�LQ�GLŲHUHQW�SOD\EDFN�VSHDNHU�FRQÀJXUDWLRQV��DQG�DQ�H[KLELWRU�FDQ�GHFLGH�KRZ�PXFK�RI�DQ�investment to make in a given theatre in order to optimize the experience within a
budget. The ideal number of speaker output channels used will vary according to
URRP�VL]H��7KH�ÀUVW�JHQHUDWLRQ�'ROE\�$WPRV�&LQHPD�3URFHVVRU�&3����FDQ�VXSSRUW�XS�WR����RXWSXWV��$OWKRXJK������FKDQQHOV�PD\�VRXQG�H[FHVVLYH�ZKHQ�FRPSDUHG�ZLWK�W\SLFDO�H[LVWLQJ�FRQÀJXUDWLRQV��PXOWLFKDQQHO�DPSOLÀHUV�WKDW�DUH�FXUUHQWO\�DYDLODEOH�make individually addressing each of, for example, 11 surrounds on each sidewall in
a large theatre a reasonable proposition.
The recommended layout of speakers for Dolby Atmos remains compatible with
previous cinema systems, which is hugely important so as not to compromise the
playback of existing 5.1 and 7.1 channel-based formats. In the same way that the
intent of the content creator must be preserved with the introduction of Dolby
Atmos, the intent of mixers of Dolby Surround 7.1 and 5.1 content must equally
be respected. This includes not changing the positions of existing screen channels
LQ�DQ�HŲRUW�WR�KHLJKWHQ�RU�DFFHQWXDWH�WKH�LQWURGXFWLRQ�RI�QHZ�VSHDNHU�ORFDWLRQV��,Q�FRQWUDVW�WR�XVLQJ�DOO����RXWSXW�FKDQQHOV�DYDLODEOH��WKH�'ROE\�$WPRV�IRUPDW�FDQ�EH�DFFXUDWHO\�UHQGHUHG�LQ�WKH�FLQHPD�WR�RWKHU�VSHDNHU�FRQÀJXUDWLRQV�VXFK�DV������DOORZLQJ�WKH�IRUPDW��DQG�DVVRFLDWHG�EHQHÀWV��WR�EH�XVHG�LQ�H[LVWLQJ�WKHDWUHV�ZLWK�QR�FKDQJH�WR�DPSOLÀHUV�RU�VSHDNHUV�
5.2.1 Optimized Playback
'LŲHUHQW�VSHDNHU�ORFDWLRQV�FDQ�GLŲHU�LQ�HŲHFWLYHQHVV�GHSHQGLQJ�RQ�WKH�WKHDWUH�design, and therefore the industry appears to agree that there is not an ideal
number or placement of channels. As a result, Dolby Atmos is adaptable and able to
play back accurately in a variety of auditoria, whether they have a limited number
RI�SOD\EDFN�FKDQQHOV�RU�PDQ\�FKDQQHOV�ZLWK�KLJKO\�ÁH[LEOH�FRQÀJXUDWLRQV�
Figure 5.1 shows a diagram of suggested speaker locations in a typical auditorium;
VSHFLÀF�GHWDLOV�DERXW�WKHVH�VSHDNHU�ORFDWLRQV�DUH�GHVFULEHG�LQ�VXEVHTXHQW�VHFWLRQV�
The reference position referred to in the document corresponds to a position two-
thirds of the distance back from the screen to the rear wall, on the center line of the
screen.
19Dolby Atmos
1/3 Room Length
2 - 3m Spacing
Additional Surround Speakers
Optional Screen Speakers
Optional Subwoofers
Figure 5.1 Recommended Speaker Locations
5.2.2 Screen Speakers
As we have studied the perception of elevation in the screen plane, we have found
WKDW�DGGLWLRQDO�VSHDNHUV�EHKLQG�WKH�VFUHHQ��VXFK�DV�/HIW�&HQWHU��/F��DQG�5LJKW�&HQWHU��5F��VFUHHQ�VSHDNHUV��LQ�WKH�ORFDWLRQV�RI�/HIW�([WUD�DQG�5LJKW�([WUD�FKDQQHOV�LQ����PP�ÀOP�IRUPDWV���FDQ�EH�EHQHÀFLDO�LQ�FUHDWLQJ�VPRRWKHU�SDQV�DFURVV�WKH�screen. Consequently, we recommend installation of these additional speakers,
SDUWLFXODUO\�LQ�DXGLWRULD�ZLWK�VFUHHQV�JUHDWHU�WKDQ����P�����IW��ZLGH��$OO�VFUHHQ�speakers should be angled such that they are aimed toward the reference position.
The recommended placement of the subwoofer behind the screen remains
unchanged, including maintaining asymmetric cabinet placement, with respect to
the center of the room, to prevent stimulation of standing waves. Figure 5.2 shows a
diagram of suggested speaker locations at the screen.
20 Dolby Atmos
Figure 5.2 Recommended Speaker Locations (Screen, Side Surrounds, and Top Surrounds)
5.2.3 Surround Speakers
6XUURXQG�VSHDNHUV�VKRXOG�EH�LQGLYLGXDOO\�ZLUHG�EDFN�WR�WKH�DPSOLÀHU�UDFN��DQG�EH�LQGLYLGXDOO\�DPSOLÀHG�ZKHUH�SRVVLEOH�ZLWK�D�GHGLFDWHG�FKDQQHO�RI�SRZHU�DPSOLÀFDWLRQ�PDWFKLQJ�WKH�SRZHU�KDQGOLQJ�RI�WKH�VSHDNHU�LQ�DFFRUGDQFH�ZLWK�WKH�PDQXIDFWXUHU·V�VSHFLÀFDWLRQV��,GHDOO\��VXUURXQG�VSHDNHUV�VKRXOG�EH�VSHFLÀHG�to handle an increased SPL for each individual speaker, and also with wider
frequency response and providing uniform coverage throughout the seating area
where possible.
As a rule of thumb for an average-sized theatre, the spacing of surround speakers
VKRXOG�EH�EHWZHHQ���DQG���PHWHUV����IW���LQ�DQG���IW���LQ���ZLWK�/HIW�DQG�5LJKW�6XUURXQG�VSHDNHUV�SODFHG�V\PPHWULFDOO\��+RZHYHU��WKH�VSDFLQJ�RI�VXUURXQG�VSHDNHUV�LV�PRVW�HŲHFWLYHO\�FRQVLGHUHG�DV�DQJOHV�VXEWHQGHG�IURP�D� given listener between adjacent speakers, as opposed to using absolute distances
between speakers.
For optimal playback throughout the auditorium, the angular distance between
DGMDFHQW�VSHDNHUV�VKRXOG�EH����GHJUHHV�RU�OHVV��UHIHUHQFHG�IURP�HDFK�RI�WKH�IRXU�corners of the prime listening area. Good results can be achieved with spacing up
to 50 degrees. For each surround zone, the speakers should maintain equal linear
spacing adjacent to the seating area where possible. The linear spacing beyond the
listening area, such as between the front row and the screen, can be slightly larger.
Side Surrounds Additional side surround speakers should be mounted closer to the screen than the
recommended practice for previous formats of starting approximately one-third
21Dolby Atmos
of the distance to the back of the auditorium. These speakers are not used as side
surrounds during playback of Dolby Surround 7.1 or 5.1 soundtracks, but will
enable smooth transition and improved timbre matching when panning objects
from the screen speakers to the surround zones.
To maximize the impression of space, the surround arrays should be placed as
low as is practical, subject to the following constraints: the vertical placement of
surround speakers at the front of the array should be reasonably close to the height
of screen-speaker acoustic center, and high enough to maintain good coverage
across the seating area according to the directivity of the speaker. The vertical
placement of the surround speakers should be such that they form a straight line
from front to back, and (typically) slanted upward so the relative elevation of
surround speakers above the listeners is maintained toward the back of the cinema
DV�WKH�VHDWLQJ�HOHYDWLRQ�LQFUHDVHV��DV�VKRZQ�LQ�)LJXUH������,Q�SUDFWLFH��WKLV�FDQ�EH�achieved most simply by choosing the elevation for the front-most and rear-most
side surround speakers, and placing the remaining speakers in a line between
these points.
The distance between side surround speakers should be determined based on the
guidelines at the start of this section.
Figure 5.3 Recommended Side Wall and Ceiling Speaker Locations
In order to provide optimum coverage for each speaker over the seating area,
the side surround speakers should be aimed toward the reference position in the
theatre, under the following guidelines:
�� Side surrounds should be angled vertically to the seats on the opposite side of
the auditorium (typically aiming 20 degrees downward).
�� Side surrounds should be angled horizontally toward the reference position.
Taking 0 degrees as aiming directly across the room:
22 Dolby Atmos
�� 1R�VSHDNHU�DQJOH�VKRXOG�H[FHHG����GHJUHHV�
�� 6SHDNHUV�DGMDFHQW�WR�WKH�VHDWLQJ�DUHD�VKRXOG�QRW�H[FHHG����GHJUHHV�
�� Speakers in the prime listening area should be left at 0 degrees.
Rear Surrounds The number of rear surround speakers, and the distance between them, should
be determined based on the guidelines at the start of this section. The back wall
speakers should have approximately the same linear spacing as the side surrounds
adjacent to the seating area, although it may be necessary to slightly increase the
density of back surrounds in order to meet the angular requirements. Such an
increase in density can also be an advantage for power handling of the left and right
rear surround zones, which are typically half the length of the side surround zones.
In order to provide optimum coverage for each speaker over the seating area, the
back surround speakers should be aimed toward the reference position in the theatre,
under the following guidelines:
�� Back surrounds should be angled vertically to the front row seats in the
auditorium (typically aiming 20 degrees downward).
�� Back surrounds should be angled horizontally toward the center line of the
auditorium. Taking 0 degrees as aiming directly toward the screen:
�� 1R�VSHDNHU�DQJOH�VKRXOG�H[FHHG����GHJUHHV�
�� Speakers in the prime listening area should be left at 0 degrees.
Top Surrounds Overhead speakers should be in two arrays from the screen to the back wall,
QRPLQDOO\�LQ�DOLJQPHQW�ZLWK�WKH�/F�DQG�5F�VFUHHQ�FKDQQHOV�RI�D�W\SLFDO�DXGLWRULXP��ZKHUH�WKH�VFUHHQ�ZLGWK�LV�HŲHFWLYHO\�WKH�ZLGWK�RI�WKH�WKHDWUH�DQG�WKH�VFUHHQ�WRS�LV�near the ceiling. They should always be placed symmetrically with respect to the
center of the screen. The top surrounds should have the same design characteristics
as the side surrounds to maintain timbre matching.
The number and spacing of the top surround speakers should be based on the
position of side surround speakers as determined using the guidelines at the start of
WKLV�VHFWLRQ��+RZHYHU��WKH�VSDFLQJ�RI�WRS�VXUURXQG�VSHDNHUV�LV�OHVV�FULWLFDO�WKDQ�IRU�side surrounds, and so it is acceptable for the number and front-back position to vary
relative to the side surrounds if necessary. The top surround array should also extend
to the screen in the same manner as the side surrounds, but it should not obstruct the
path of the projection light.
23Dolby Atmos
.
The lateral position of the arrays should be chosen to optimize spatial immersion and
uniformity across the listening area. As stated earlier, placing the top surround speaker
DUUD\V�LQ�DOLJQPHQW�ZLWK�/F�DQG�5F�VFUHHQ�FKDQQHOV�ZLOO�JHQHUDOO\�JLYH�JRRG�UHVXOWV��)RU�URRPV�ZKHUH�WKH�VHDWLQJ�DUHD�LV�VLJQLÀFDQWO\�ZLGHU�WKDQ�WKH�VFUHHQ��RU�WKH�WRS�VXUURXQGV�DUH�PRXQWHG�VLJQLÀFDQWO\�KLJKHU�WKDQ�WKH�OHYHO�RI�WKH�WRS�RI�WKH�VFUHHQ��LW�LV�GHVLUDEOH�to have the overhead arrays more widely spaced. The minimum width is the Lc and
5F�VSDFLQJ��7KH�PD[LPXP�ZLGWK�VKRXOG�EH�GHWHUPLQHG�EDVHG�RQ�HOHYDWLRQ�DQJOHV�DV�follows:
/HW�(�EH�WKH�HOHYDWLRQ�DQJOH�RI�WKH�QHDUHVW�VLGH�VXUURXQG��PHDVXUHG�IURP�D�UHIHUHQFH�position in the middle of the seating area (typically 15 to 25 degrees). The elevation
DQJOH�RI�WKH�FRUUHVSRQGLQJ�WRS�VXUURXQG�DUUD\�VKRXOG�EH�JUHDWHU�WKDQ�RU�HTXDO�WR����GHJUHHV�SOXV�KDOI�RI�DQJOH�(�DV�VKRZQ�LQ�)LJXUH������)RU�H[DPSOH��LI�(�LV����GHJUHHV��then the elevation angle of the top surround array should be greater than or equal to 55
degrees.
5.3 nDolby Atmos Commissioning Service
To ensure that screens equipped with Dolby Atmos achieve accurate and consistent
SOD\EDFN�LQ�HYHU\�'ROE\�$WPRV�DXGLWRULXP��'ROE\�$WPRV�&LQHPD�3URFHVVRU�&3����SXUFKDVHV�LQFOXGH�D�UHYLHZ�RI�WKH�VSHDNHU�FRQÀJXUDWLRQ�GHVLJQ�DQG�DQ�LQLWLDO�equalization of the theatre.
Dolby Content Services engineers review design drawings and equipment selection,
XVLQJ�'ROE\�$WPRV�'HVLJQHU�6RIWZDUH�WR�HQVXUH�WKDW�WKH�VSHDNHU�DQG�DPSOLÀHU�SDLULQJV��as well as their placement and positioning, deliver the best Dolby Atmos performance
SRVVLEOH�IRU�VSHFLÀF�DXGLWRULXP�FRQÀJXUDWLRQV�
Dolby Atmos Designer software, included as part of the Dolby Atmos Commissioning
Service, helps technicians and equipment integrators optimize Dolby Atmos system
setup in any room. The software provides a full set of powerful tools integrated into an
LQWXLWLYH�LQWHUIDFH�ZLWK�D�VWHS�E\�VWHS�ZL]DUG�WR�FRQÀJXUH�WKH�DXGLWRULXP�DQG�DXWRPDWLF�equalization to calibrate each room.
Dolby Laboratories, Inc.100 Potrero Avenue, San Francisco, CA 94103-4813 USA T 415-558-0200 F 415-645-4000 dolby.com
Dolby, Lake, and the double-D symbol are registered trademarks of Dolby Laboratories. Surround EX is a trademark of Dolby Laboratories. THX is a registered trademark of THX Ltd. © 2013 Dolby Laboratories, Inc. All rights reserved. S13/25536/26858
Recommended
