WO2014068583A1

WO2014068583A1 - Multi platform 4 layer and x, y, z axis audio recording, mixing and playback process

Info

Publication number: WO2014068583A1
Application number: PCT/IN2013/000220
Authority: WO
Inventors: Anirvan GHOSE
Original assignee: Pulz Electronics Pvt. Ltd.
Priority date: 2012-11-02
Filing date: 2013-04-03
Publication date: 2014-05-08

Abstract

The present invention relates to a Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow sounds to be moved over 4 layers on the X, Y axis along the length of the room. It is an 11 Channel sound format offering great opportunity to sound mixers to place sounds anywhere in the auditorium thereby achieving greater audience involvement in the film. The format uses an extremely simple and easy to upgrade path whereby existing workflows and equipment for audio post production can be retained. The invention provides a great opportunity to create a XYZ axis audio experience at home without using any up mixing or virtual channel enhancement through digital signal processing.

Description

TITLE OF THE INVENTION : Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process.

PREAMBLE OF INVENTION- This invention in particular describes the nature of the invention and the manner in which it is to be performed.

FIELD OF INVENTION- The disclosures made herein relate generally to the audio recording, mixing and playback and more specifically related to process for Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process.

BACKGROUND OF THE INVENTION INCLUDING PRIOR ART:

Today content is played over multiple platforms. A movie plays back in a cinema, goes over the broadcast chain and is played at home. Existing multi-platform audio formats (those which play in cinema as well as home) are 5.1 and 7.1. These formats record and reproduce sound over the XY axis. There is no audio information recorded or played back in the Z axis (height).

The existing 5.1 format offers speakers in the front and back. However, within the side (which is the entire length of the auditorium) there is no possibility of movement of sound. This offers only 2 layers of movement - either front or back.

Some home systems have attempted to use digital signal processing to derive height information (Z axis) from the existing soundtracks. However, this is not realistic and reliable as no Z axis information is currently captured and recorded in the movie soundtracks.

The existing 7.1 system in cinema requires dual inventory of KDMs for Digital Cinema Prints, one for 5.1 and the other for 7.1. It is not possible to manage and track which cinema has which system across the world and send KDMs accordingly. Besides, movies being played within a multiplex complex get shifted around from one screen to another due to programming requirements. Different screens within the complex might have a mix of 5.1 and 7.1 screens making the KDM management even more difficult. United States Patent Application 20070225842 relates to a multichannel audio format to provide a truly discrete as well as a backward compatible mix for surround-sound, front or other discrete audio channels in cinema, home theater, or music environments. The additional discrete audio signals are mixed with the existing discrete audio channels into a predetermined format such as the 5.1 audio format. In addition these additional discrete audio channels are encoded and appended to the predetermined format as extension bits in the bitstream. The existing base of multichannel decoders can be used in combination with a mix decoder to reproduce truly discrete N. l multichannel audio.

The existing invention as mentioned above seems to provide a way of encoding more number of discrete channels than what is available by using extension bits. The present system uses the existing channels available in DCPs and a codec for consumer audio. It does not use any such encoding for recording additional channels in an existing system.

In United States Patent 7206648, a multi-channel audio reproducing apparatus including several audio power amplifiers, the number of which is less than the number of channels required for the multi-channel format of the input audio signals is disclosed. The multichannel audio reproducing apparatus also includes a decoder^' for decoding input audio signals and a signal processor, arranged between the decoder and the audio power amplifiers, for receiving decoder output signals of a plurality of channels of the multi-channel format at the input channels thereof and for outputting, . at the output channels thereof, audio signals of channels of a number less than the number of audio power amplifiers. A controller controls the signal processor in response to setting information of the connection and installation of a plurality of speakers to which the outputs of the audio power amplifiers are respectively supplied.

The technology used in the above existing invention as mentioned above is for reducing the number of power amplifiers than the number of channels. The present invention uses a minimum of same number of amplifiers as the number of channels. The number of power amplifiers in the present invention can be more than the number of channels but not less.

United States Patent Application 20110305344 relates to method and apparatus to .· encode audio with spatial information in a manner that does not depend on the exhibition setup, and to decode and play out optimally for any given exhibition setup, maximizing the sweet-spot area, and including setups with loudspeakers at different heights, and headphones. The part of the audio that requires very precise localization is encoded into a set of mono tracks with associated directional parameters, whereas the remaining audio is encoded into a set of Ambisonics tracks of a chosen order and mixture. Upon specification of a given exhibition system, the exhibition-independent format is decoded adapting to the specified system, by using different decoding methods for each assigned group.

The present invention mentioned above does not encode audio with spatial information. In present invention, the system has fixed layouts for cinemas, home etc. The present invention does not use any headphones or record any localization information onto mono tracks. This present invention is not an exhibition independent format and do not use any decoding to that effect.

United States Patent Application 20100166191 relates to method and apparatus for conversion between multi - channel audio formats.

The present invention mentioned above does not convert one form of multi-channel audio to another. It records mixes and plays back as per the specified format. It only creates a 5.1 compatible down mix for playback environments which is equipped only with a 5.1 system.

United States Patent Application 20050088934 relates to recording and playback of multi- channel digital audio having different resolutions for different channels.

In the above present invention, all channels use the same resolution.

United States Patent 6507658 relates to method and apparatus that implements a novel surround sound panning paradigm. Rather than controlling the x-y position of a perceived sound source within a linear grid, the perceived sound is characterized by specifying perceived arrival energy as a function of direction of arrival. In one embodiment, perceived sound source azimuth and width (or spatial extent) is specified, which parameters are used in a novel panning law to control each output channel. In a preferred implementation, the panning control is provided in a Plug-In application for a conventional DAW environment such as Pro Tools, which application includes an interface that provides precise control over the direction and spatial extent of audio.

The present invention uses modified X-Y panners based on a linear grid. The panner has no functions for arrival energy as a function of direction of arrival.

United States Patent 6694027 relates to discrete multi channel/5-2-5 matrix system. One embodiment of the system provides additional output channels by matrix encoding the additional audio information into the rear surround channels of a discrete digital five channel surround system. In a second embodiment the system provides a surround encode/decode system offering eleven independently addressable output channels.

The present invention uses discrete channels of audio and does not use any Matrix system

The prior art Systems described in the foregoing descriptions have an inherent limitation.

Therefore, by dint of determined research and intuitive knowledge, the inventor has developed a Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow sounds to be moved over 4 layers on the X, Y axis along the length of the room.

SUMMARY OF THE INVENTION:

It is therefore, an aspect of the present invention to provide a Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow sounds to be moved over 4 layers on the X, Y axis along the length of the room.

The present invention is an 11 Channel sound format offering great opportunity to sound mixers to place sounds anywhere in the auditorium thereby achieving greater audience involvement in the film.

It allows the 11 channel soundtrack along with a 5.1 soundtrack to be distributed to cinemas using a single KDM thereby reducing distribution problems. It allows audio with XYZ axis recordings to be played back at home. OBJECT OF THE INVENTION: -

The main object of the present embodiment is to overcome all the associated drawbacks and provide a Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow sounds to be moved over 4 layers on the X, Y axis along the length of the room.

Another object of the present invention is to provide for an 11 Channel sound format offering great opportunity to sound mixers to place sounds anywhere in the auditorium thereby achieving greater audience involvement in the film.

Still another object of the present invention is to provide for a 11 channel soundtrack along with a 5.1 soundtrack to be distributed to cinemas using a single KDM thereby reducing distribution problems. It allows audio with XYZ axis recordings to be played back at home.

Yet another object of the present invention is to provide a Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process which allows X, Y and Z axis panning of audio elements with a X,Y axis (2 dimensional) panning tool.

Further object of the /present invention is to provide a Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow a single audio mix in X,Y, Z axis to be created which can be played back in multiple environments.

Other object of the present invention is to provide a Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow a cinema or home theatre equipped with this system to playback existing 5.1 soundtracks in its correct form.

Still further object of the present invention is to provide a Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow a theatre equipped with a 5.1 system to playback a soundtrack produced in this process in 5.1.

Another object of the present invention is to provide a Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process which can be played back .· on all DCI approved servers without modification. BRIEF DESCRITION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate one or more embodiments of the present invention and, together with the detailed description, serve to explain the principles and implementations of the invention.

In the drawings:

1. Figure 1 is a diagram schematically illustrating typical layout of speakers and channels in a typical cinema.

2. Figure 2 is a diagram schematically illustrating side elevation view of speaker placement in a cinema.

3. Figure 3 is a diagram schematically illustrating each channel in a cinema providing equal 45 degree angles from the ideal sitting position, thereby allowing smooth panning in the horizontal plane.

4. Figure 4 is a diagram schematically illustrating the 4 horizontal layers over which sound can be moved from front to back.

5. Figure 5 is a diagram schematically illustrating the typical layout of a studio where this soundtrack should be mixed for this invention.

6. Figure 6 is a diagram schematically illustrating side elevation view of such a studio. .

7. Figure 7 is a diagram schematically illustrating the panner (panning tool) layout required to pan objects for this invention.

8. Figure 8 is a diagram schematically illustrating a microphone rig required to record sound for this invention.

9. Figure 9 is a diagram schematically illustrating a microphone rig required to record sound for this invention. 10. Figure 10 is a diagram schematically illustrating how surround speakers from different channels should be powered by different channels of amplifiers.

11. Figure 11 is a diagram schematically illustrating the location of the point for the ceiling speaker.

12. Figure 12 is a diagram schematically illustrating the maximum permissible angle of the ceiling speaker with respect to the front and last row.

13. Figure 13 is a diagram schematically illustrating a layout using 2 ceiling speakers as the angles are exceeded using 1 speaker.

14. Figure 14 is a diagram schematically illustrating a layout using 4 ceiling speakers as the coverage is not achieved using 2 speakers as the auditorium is wide.

15. Figure 15 is a diagram schematically illustrating the placement of optional column sub woofers on the back wall.

16. Figure 16 is a diagram schematically illustrating the placement of optional column subwoofers on the side walls.

17. Figure 17 is a diagram schematically illustrating typical amplifier configuration for a cinema.

18. Figure 18 is a diagram schematically illustrating the internal signal block diagram of a cinema processor which can play back soundtracks recorded with this process.

19. Figure 19 is a diagram schematically illustrating the internal signal block diagram of a cinema processor setup for this invention, playing back a 7.1 soundtrack.

20. Figure 20 is a diagram schematically illustrating the internal signal block diagram of a cinema processor setup for this invention, playing back a 5.1 soundtrack.

21. Figure 21 is a diagram schematically illustrating typical layout of a home theatre setup to playback soundtracks recorded using this invention. 22. Figure 22 is a diagram schematically illustrating the placement angles of speakers for setting up a home theatre configuration for playback of soundtracks using this invention.

DETAILED DESCRIPTION OF INVENTION-

The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment.

Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or matter.

The present invention is directed to a Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and playback process which allow sounds to be moved over 4 layers on the X, Y axis along the length of the room.

The present invention is an 11 Channel sound format offering great opportunity to sound mixers to place sounds anywhere in the auditorium thereby achieving greater audience involvement in the film. The format uses an extremely simple and easy to upgrade path whereby existing workflows and equipment for audio post production can be retained. The invention provides a great opportunity to create a XYZ axis audio experience at home without using any up mixing or virtual channel enhancement through digital signal processing.

The present invention allows the 11 channel soundtrack along with a 5.1 soundtrack to be distributed to cinemas using a single KDM thereby reducing distribution problems.

The present invention allows audio with XYZ axis recordings to be played back at home.

The present invention consist of the following channel configuration - Left, Centre, Right, Left Surround Front, Right Surround Front, Left Surround Rear, Right Surround Rear, Left Back Surround, Right Back Surround, Top Surround and LFE. The Left, Centre, Right and LFE channel speakers are located in front (Behind the screen for Cinema). The Left wall speakers are divided into 2 clusters - Left Surround Front and Left Surround Rear. The right wall speakers are also arranged in a similar fashion. The back wall speakers are divided into 2 clusters - Left Back Surround and Right Back Surround. There is a single channel driving one or a single cluster of speakers suspended from the Ceiling. The same is demonstrated in Fig 1 and Fig 2

The invention records the soundtrack on 13 channels of audio within which there are 2 channels of down-mixed left surround and right surround information forming a 5.1 mix. This ensures that single KDMs can be used in cinema without the need to have multiple inventories of KDMs. A 16 channel cinema processor can play back all the 11 channels while a 8 channel processor with a 5.1 system can playback a 5.1 soundtrack. The front speakers are maintained like a 5.1 configuration. This allows complete compatibility for old 5.1 soundtracks and playback compatibility for cinemas and home systems with 5.1 systems.

Advantages of the present invention - a. Improvements in the horizontal plane

The separation into 6 surround clusters provide for smoother 360 degree panning in the horizontal plane. The 6 clusters along with screen speakers form 8, equal 45 degree intervals from the prime listening area at 2/3 ^rd the length of the auditorium or a home cinema. This allows uniform panning through 360 degrees. This is not possible in 5.1 or 7.1 layouts. The same is demonstrated in Fig 3.

This further facilitates objects to be moved from front to back over 4 layers providing more depth to the soundtrack. The same is demonstrated in Fig 4 b. Improvements in the vertical plane

In our everyday environment, there are many sound sources with a significant angle of elevation. Our standard 5.1 and 7.1 surround sound formats allow sounds to be recorded and reproduced only in one horizontal plane. The addition of the top surround speakers in the present invention allows height information to be captured during recording and reproduced in cinema and the home environment.

Some examples of elevated sound sources in our everyday life are mentioned as under -

Natural surroundings - wind, leaves rustling, aero planes, helicopter, birds, flora and fauna, reflections inside caves etc.

Constructed environments - under bridges, underground tunnels, inside buildings with activity on higher floors, railway station and airport announcements, fan in a room, lobby music in hotels, standing under a shade in the rain, firecrackers etc.

Apart from environmental elevated sources, the top surround speakers allow mixing engineers to pan objects over the head from front to back, left to right, ^' left front corner to right back corner etc.

The present invention allows an extremely easy upgrade path for cinemas by adding a cinema processor, 3-4 channels of amplification and a single or few of top surround speakers.

A Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and playback process involves the following various stages

1. Setting up of new film mixing studios or upgrading existing film mixing studios to create content as per this invention. a. Studio Layout

Speaker positions and layout of the studio are shown in fig 5 & 6

The mixing console should provide 8 pairs (16 channel) AES outputs for connection to the cinema processor for monitoring. The studio should be equipped with a 16 channel cinema processor with software integration as per section 5f. Alternately, 2 8 channel processors can also be used.

The studio should be calibrated as per section 5f.

b. Panning

A special panning tool is required to pan sound sources over 9 channels in the horizontal plane and 1 channel in the vertical plane.

A XY axis panner used for the purpose is shown in fig 7

A toggle selection for the top surround speaker is required to move objects directly from screen speakers to back surround speakers without passing through the top surround when the switch is in "Top Surround OFF" mode.

This panning option can be used as a plug-in inside the workstation or updated within existing digital consoles with required software modification. c. XYZ axis Reverbs

Reverb algorithms using reflections in X, Y and Z axis need to be used along with separate outputs paths for assigning the outputs to the 10 channels. er the film mix studio is setup, the next step is content creation a. Recording ambience in Χ,Υ,Ζ axis

Ambience should be recorded using a 10 track or a 8 track recorder. Microphones with a narrow angle of coverage should be used for the horizontal plane and one microphone for the vertical plane.

Microphone configuration with a 10 track digital recorder is shown in fig 8. Microphone configuration with a 8 track digital recorder is shown in fig 9 b. Recording Dialogues

Dialogues need to be recorded in the same format used for 5.1. No changes required. c. Recording Music

Music recording studios need to provide separate elements for mixing in the mix studio setup with the monitoring mentioned above. If the music studio desires to mix the music, the music studio also needs to be equipped similarly as above and provide a music stem in the following track format:

d. Recording Effects

Effects with moving objects need to be recorded using the similar equipment mentioned for "Ambience recording" in section 2a. The microphone rig needs to be positioned keeping in mind the camera angle and how the audio is supposed to be panned on-screen. The side of the rig marked "front" in fig 8 and 9 should be pointing in the same direction as the camera and placed close to it. This microphone rig should specially be used in locations / scenes where there are sound sources at a height,

Film Mixing and Mastering

This invention being a channel based system, film mixes can be created using the studios existing mixing infrastructure (16 AES outputs required). Upgrades are required in the monitoring, cinema processor and the panning section:

A film mix needs to be created using 11 channels on a DAW. 11 mix busses need to be assigned to the 11 channels of monitoring. The final mix master should be recorded on 11 channels in the following track configuration:

Each premix and stem also needs to be created using the above track configuration.

Bass management should be used for all surround and screen channels during mixing to ensure smooth pans across the system, routing the low frequency components to the LFE channel.

If an existing 5.1 premix / stem needs to be used for this process mix due to unavailability of additional components, the following track assignment should be used along with level correction of the surround channels:

l Cinema Master Creation and Distribution Audio track configuration for DCP

Once the 11 channel final mix is created, the surround channels need to be folded down to create a 5.1 Left Surround and 5.1 Right Surround channel for compatibility of the DCP to be played in 5.1 theatres. The combination of the surround channels should be as follows:

10.1 MLX

MASTER 5.1 LS RS

LSF (gain

5.1 LS

reduction) +

LSR (gain

reduction) +

LBS (gain

reduction) +

TS (gain

reduction)

RSF (gain

5.1 RS

reduction) +

RSR (gain

reduction) + RBS (gain

reduction) +

TS (gain

reduction)

After creation of the 5.1 Ls and Rs tracks, the final audio master needs to be created. The final audio master should have the following track configuration:

Channels 9 and 10 in a DCP package is normally assigned to the Lc and Rc channels. Theatres having Lc and Rc channels and having the outputs 9 and 10 of the server wired to the Lc and Rc channels should keep the Lc and Rc amplifiers off while playing back a film mixed using this process. KDMs All the 11 channels of the Final Mix along with the 5.1 mix are contained in the sixteen channels of audio. Hence separate KDMs for 5.1 and 10.1 are not required. Content delivery for home

The soundtracks as per this invention can be delivered to home by using a 13 channel compression codec. The soundtrack is encoded using a software encoder at 48KHz and 16/20/24 bit. The encoder is used during the authoring stage of the content. The final mix from the above mentioned mix studio is delivered as WAV files. These WAV files are synchronized with the picture. At the authoring stage, an option is created in the title menu to select this sound format to be played.

Home theatre processors / AV Receivers should have the required decoding facility to playback soundtracks encoded with this process. Setting up of new Cinema Theatres or upgrading existing Cinemas to playback content as per this invention. a. Screen Loudspeakers

The screen loudspeakers follows SMPTE guidelines for cinemas with 3 screen speakers Left, Centre and Right behind the screen. This ensures compatibility with existing soundtracks. The Centre speaker is placed at the centre line of the screen and the Lef lind Right speakers placed towards the left and right ends of the screen. The height of the screen speakers are positioned such that the HF unit is 2/3rds the height of the screen.

The height of the screen speakers are positioned such that the HF unit is 2/3rds the height of the screen.

The power handling capacity of the LCR speakers, subwoofers and the number of subwoofers required for a particular cinema depends on the size of the cinema. b. Surround Speakers The surround speaker placement when using groups of speakers should be as per the SMPTE guidelines, to ensure compatibility with earlier soundtracks.

The surround speakers should be individually wired back to a junction box near the location of the amplifier rack. At the junction box, the surround speakers are grouped into 6 clusters - The left wall is divided into 2 groups (Left front and Left rear), The right wall is divided into 2 groups (Right front and Right rear), The back wall is also divided into 2 group (Left back and Right back). This is demonstrated in Fig 10

Speakers within each group should be combined in series and parallel to achieve the best impedance match for the amplifiers driving them. Each group of surround speakers should be powered by one channel of amplification, i.e a total of 6 channels of amplification.

Ideally, array of surround speakers should be avoided. Single high power full bandwidth speakers with horizontal coverage of greater than 110 degrees should be used. These speakers should be placed at the 45 degree locations as shown in fig 3. Multiple speakers in array formation is only required if the single speakers create too much of a hot spot for a particular auditorium due to size and seating layout restrictions.

The power handling capability, quantity of the surround speakers, and the power of the amplifiers driving them for a particular cinema depends on the size of the cinema. Top Surround Speakers

The top surround speakers should be co-axial speakers for uniform 90 degree dispersion pattern in all directions without comb filtering. Ideally, one top surround speaker should be used, however, multiple speakers are required if the ceiling height is low and the entire audience area cannot be covered by one speaker.

Single speaker configuration The centre point (P on fig 11) between the screen speaker and the back surround speaker in the vertical plane on the ceiling is the location for the single speaker. This is shown in Fig 11.

From this point, the coverage of the entire seating area is verified. The horizontal angle from all seats should be between 40 degrees to 120 degrees. This is shown in Fig 12.

2 speaker configuration

If the length of the auditorium is more compared to the height, 2 top surround speakers are required. This is shown in Fig 13.

4 speaker configuration

If the length and width are more compared to the height, 4 top surround speakers are required. The left and right top surround speakers should be equidistant from the centre line, following the same calculation as the 2 speaker configuration. This is shown in Fig 14. d. Optional Surround Subwoofers

Optional subwoofers can be used for the surround speakers. Small diameter (6") column subwoofers should be used on the side and back walls. Bass management with a 120Hz cut off frequency should be used to route the low frequency components of all the surround channels to these subwoofers. This is shown in Fig 15 & 16. e. Cinema amplifier configuration

The screen speakers should be at least bi-amplified with an active crossover. Each surround cluster should be driven by one channel of amplification. This is shown in Fig 17. f. Cinema Processor Configuration i) Cinema Processor requirement

Cinema processors are required to have a minimum of 16 channel AES inputs and 16 channel analog outputs. The processor needs to have one AES output for feeding motion control equipment. Each channel should offer l/3^rd octave equalization, level control, delay for surround channels, non sync inputs, master volume control and mute, full bandwidth internal pink noise at calibrated level for speaker alignment.

ii) Custom software integration within processor for this invention

The cinema processor should have a format selection menu. The signal routing and block diagram for the signal path is as per fig 18.

The processor should provide a single AES output for motion control.

The signal routing and block diagram for the signal path for 7.1 playback is as per fig 19.

The signal routing and block diagram for the signal path for 5.1 playback is as per fig 20. iii) Cinema Processor calibration

The processor should provide calibrated pink noise for each output channel.

The cinema processor should provide l/3^rd octave equalization along with bulk bass and bulk treble controls for every output channel. It should also provide a selection for the turn over f equency for the bulk treble control.

Each speaker should be equalized as per ISO 2969 curve or applicable variation as per room size.

Delays for the surround channels should be set calculating the difference in time of arrival between the screen speaker and the respective surround channel.

SPL calibration for the output channels: L, R, C, FLS, FRS, RLS, RRS, BLS, BRS, TS should be calibrated to 85 dB C weighted slow.

SW should be calibrated to 90 - 92 dB C weighted slow. g. Playback of 5.1 and 7.1 content

The cinema processor should provide gain reduction and routing functions of the surround channels for 5.1 and 7.1 playback modes. Setting up of new Home Theatres or upgrading existing Home Theatres to playback content as per this invention.

A typical speaker layout in a home theatre environment is shown in Fig 21 & 22

Home theatre processors / AV Receivers should have the required decoding facility to playback soundtracks encoded with this process. Broadcast

The same process can be followed to provide the same audio experience on television. The encoding should be done at the final stage prior to transmission. A Set-top box equipped to pass on the encoded audio bit stream to the home theatre processor equipped with this decoding facility can decode the soundtrack. The set-top box also needs to have a built-in decoding facility to down-mix a stereo output for televisions and home theatre setups not equipped with this decoding facility. During the down-mix process within the set-top box, the 5.1 content using the 5.1 Ls Rs channels are used for the stereo down-mix.

Gaming

Audio recorded with the above process can be used to create a more involving gaming experience. The speaker layout as per fig... can create a 360 degree sound source at 45 degree intervals along with the heath channel as well. A gaming console equipped with providing an encoded bit-stream output and a home theatre equipped with this decoding facility and speaker layout is required for playback.

This process will provide sounds to be moved around the player, above the · player and make the experience more involving.

The audio files recorded with this process should be stored in the game programme and mapped along with actions. The required files are played back during mapped responses and the encoded output feeds the home theatre which decodes this and routes the audio to the respective speakers.

DETAILED DESCRIPTION OF THE DRAWINGS -

A complete understanding of the present invention may be by reference to the following detailed description which taken in connection with the accompanying drawings, wherein

Fig 1 schematically illustrates the typical layout of speakers and channels in a typical cinema. The following channel configuration - Left, Centre, Right, Left Surround Front, Right Surround Front, Left Surround Rear, Right Surround Rear, Left Back Surround, Right Back Surround, Top Surround and LFE is illustrated in Fig 1.

2. Figure 2 schematically illustrates side elevation view of speaker placement in a - cinema. The figure also shows the placement of the ceiling surround speaker to reproduce the Z axis signals.

3. Figure 3 schematically illustrates the improvement done in the horizontal plane. Each channel in a cinema provides equal 45 degree angles from the ideal sitting position, thereby allowing smooth panning in the horizontal plane. The 360 degrees on the horizontal plane is divided into equal divisions of 45 degrees. Each of these speakers and speaker clusters are calibrated equally at 85 dB SPL, thereby allowing smooth panning in the horizontal plane. In current 5.1 or 7.1 formats, the screen speakers are calibrated at 85 dB while the surrounds are at 82 dB thereby providing un-uniform panning.

4. Figure 4 schematically illustrates another embodiment of the improvement done in the horizontal plane. It illustrates the 4 horizontal layers over which sound can be moved from front to back. This provides more depth to the sound track. A sound source can be moved from layer 1, then to layer 2, then 3 and finally 4, providing a smooth sense of movement across the length of the auditorium.

5. Figure 5 schematically illustrates the typical layout of a studio where this soundtrack should be mixed for this invention. From the mixing position, each speaker / speaker cluster is at 45 degrees apart.

6. Figure 6 schematically illustrates side elevation view of a studio layout. This also shows the placement and position of the ceiling speaker for the Z axis signal reproduction.

7. Figure 7 schematically illustrates the panner (panning tool) layout required to pan objects for this invention. A special panning tool is required to pan sound sources over 9 channels in the horizontal plane and 1 channel in the vertical plane. A XY axis panner used for the purpose is shown in the diagram. When the "top surround on/off ' switch is in off position, sound can be panned between any speaker to any speaker in the horizontal plane. When the "top surround on/off switch is in on position, the sound can be panned from one speaker to another on the opposite wall via the ceiling speaker. ¹

8. Figure 8 schematically illustrates a microphone rig required to record sound for this invention. This rig uses 10 microphones and a 10 channel recorder. This rig uses 10 microphones to record sounds, each microphone placed at 45 degrees similar to the speaker layout. This rig requires a 10 channel recorder to record all the 10 microphone outputs.

9. Figure 9 schematically illustrates a microphone rig required to record sound for this invention. This rig uses 8 microphones. One centre and one back microphone are eliminated to reduce the number to 8. This is required to accommodate 8 channel recorders which are more popular. 10. Figure 10 schematically illustrates how surround speakers from different channels should be powered by different channels of amplifiers. The surround speakers are individually wired back to a junction box near the location of the amplifier rack. At the junction box, the surround speakers are grouped into 6 clusters - The left wall is divided into 2 groups (Left front and Left rear), The right wall is divided into 2 groups (Right front and Right rear), The back wall is also divided into 2 group (Left back and Right back).

11. Figure 11 schematically illustrates the location of the point for the ceiling speaker. This is determined by finding the angular midpoint between the front and the rear speakers. The centre point between the screen speaker and the back surround speaker in the vertical plane on the ceiling is the location for the single speaker.

12. Figure 12 schematically illustrates the maximum permissible angle of the ceiling speaker with respect to the front and last row. If these angles are exceeded, more number of ceiling speakers is required. The vertical angle from all seats should be between 40 degrees to 120 degrees. From the ideal seating position, the ceiling speaker should form the mid-point of the pan from front to back.

13. Figure 13 schematically illustrates a layout using 2 ceiling speakers as the angles are exceeded using 1 speaker. Due to the size and ratio of this auditorium, the maximum permissible angles are exceeded using 1 speaker. This is required if the height of the auditorium is too low compared to the length of the auditorium.

14. Figure 14 is a diagram schematically illustrating a layout using 4 ceiling speakers as the coverage is not achieved using 2 speakers as the auditorium is wide. Similar to figure 13, this auditorium has less height compared to length and hence 2 speakers were added instead of 1. In addition to figure 13, this auditorium width is also too much compared to the length. Hence 2 more speakers had to be added to form a cluster of 4 speakers covering the entire auditorium.

15. Figure 15 is a diagram schematically illustrating the placement of optional column subwoofers on the back wall. The surround speakers being small in size have limitations in the low frequency response. Subwoofers can be added to compensate for these making the channel full-bandwidth, thereby making the pans even smoother. Bass management is used to derive the subwoofer output from the surround channel outputs..

16. Figure 16 schematically illustrates the placement of optional column subwoofers on the side walls, is for similar purpose as figure 15.

17. Figure 17 schematically illustrates typical amplifier configuration for a cinema.

18. Figure 18 is a diagram schematically illustrating the internal signal block diagram of a cinema processor which can play back soundtracks recorded with this process. The 11 channels pass through equalization, delay and level settings need to be carried out during the installation of the processor.

19. Figure 19 is a diagram schematically illustrating the internal signal block diagram of a cinema processor setup for this invention, playing back a 7.1 soundtrack. The surround information needs to be divided along all the speakers using automatic switching in the processor and level compensation applied for correct playback of 7.1.

20. Figure 20 is a diagram schematically illustrating the internal signal block diagram of a cinema processor setup for this invention, playing back a 5.1 soundtrack. Different routing, switching and level compensation is required for surround channels for correct playback of 5.1 soundtracks.

21. Figure 21 schematically illustrates typical layout of a home theatre setup to playback soundtracks recorded using this invention.

22. Figure 22 schematically illustrates the placement angles of speakers for setting up a home theatre configuration for playback of soundtracks using this invention.

Claims

CLAIMS - We claim -

1. A Multi Platform, 4 layer, and Χ,Υ,Ζ axis audio recording, mixing and .■ playback process which allow sounds to be moved over 4 layers on the X, Y axis along the length of the room.

2. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which allow capture and playback of sound at 45 degree angular intervals in the X, Y axis providing smooth panning at uniform intervals.

3. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which is designed on open standard for cinema playback and offers X,Y and Z axis audio.

4. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which allows X, Y and Z axis panning of audio elements with a X,Y axis (2 dimensional) panning tool.

5. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which allow a single audio mix in X,Y, Z axis to be created which can be played back in multiple environments.

6. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which allow a cinema or home theatre equipped with this system to playback existing 5.1 soundtracks in its correct form.

7. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which allow a theatre equipped with a, 5.1 system to playback a soundtrack produced in this process in 5.1.

8. A Multi Platform 4 layer and Χ,Υ,Ζ axis audio recording, mixing and playback process according to claim 1 which can be played back on all DO approved servers without modification.