MAY1206 PROJECT PLAN AUDIO PROCESSOR

MAY1206 PROJECT PLAN: AUDIO PROCESSOR

Iowa State University

Senior Design

CLIENT

Texas Instruments

FACULTY ADVISOR

Dr. Randall Geiger

TEAM MEMBERS

Matthew Rench Morgan Hodge Max Jablonski Xuetong Mao Brian Joyce

CONTENTS Problem/Need Statement ............................................................................................................................. 1

Concept Sketch ............................................................................................................................................. 1

System description ........................................................................................................................................ 2

Operating environment ................................................................................................................................ 2

User interface description ............................................................................................................................ 3

Requirements statement .............................................................................................................................. 3

Functional requirement ................................................................................................................................ 3

Non-functional requirement ......................................................................................................................... 3

Market/Literature Survey ............................................................................................................................. 4

Deliverables................................................................................................................................................... 4

Design Specifications ................................................................................................................................ 4

Engineering Report ................................................................................................................................... 5

Operating Prototype ................................................................................................................................. 5

Work Plan ...................................................................................................................................................... 5

Work breakdown structure ....................................................................................................................... 5

Research 35% ........................................................................................................................................ 5

Design 20% ............................................................................................................................................ 6

Implementation 20% ............................................................................................................................. 6

Blind testing 10%................................................................................................................................... 6

Debugging/validation 15% .................................................................................................................... 6

Resource Requirements ................................................................................................................................ 6

Project Schedule ............................................................................................................................................ 6

Risks .............................................................................................................................................................. 9

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PROBLEM/NEED STATEMENT

Cable TV channels frequently and intentionally increase the audio level of commercial content to garner

attention. This is an annoyance to consumers, and they wish for a solution. While some TVs include audio

processing to mitigate this problem, it is believed improvements can be made. The objective of this project

is to develop a prototype audio processor with amplitude-leveling capability. According to the requirements,

the implementation could be analog, digital, or any combination between.

CONCEPT SKETCH In a specific use case, the device is connected between the television and the receiver of the speakers using

RCA cords. The setup is shown below in Figure 1.

The device targets commercials that have a higher average peak amplitude than the television program, as

seen in Figure 2. The device will then adjust the gain of the signal to create a more level amplitude.

Figure 1. Use of Device Concept Sketch

Figure 2. Modification of Signal

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SYSTEM DESCRIPTION

The audio signal is input to the device. If the user has the device turned on, the signal is then analyzed to

determine if the signal exceeds a specific design level. The signal is then modified if necessary and then

output to the auxiliary component. If the device is turned off, the original signal will be output. This logic is

shown below in Figure 3.

OPERATING ENVIRONMENT Users that purchase the device will be people who care about the television “experience”. They are annoyed

by the commercials and actively sought out a solution to fix it. Therefore, the device is expected to be used

with high quality audio speakers and equipment in addition to the standard TV speakers. The device will

need to be able to limit the unwanted distortion so it can be used with all ranges of audio equipment from

high end to low end.

In order to be used, the device will be paired with a TV at all times. It is expected that it can be used

anywhere television streams are watched. This means the device will be indoors or weather protected with

access to an AC power source. Thus, running on battery power or weatherproofing will not be addressed.

Figure 3. Block Diagram

Decide if the signal exceeds

the designed level Input Signal

Process with volume

leveler

Keep original signal

Output signals

Is device

turned on? If Yes

If No

If No

If Yes

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USER INTERFACE DESCRIPTION Installation will be the only major part of user interaction of this device. The device will have a set of RCA

audio inputs and outputs. The television audio will be connected to the inputs, and the user’s sound system

will be connected to the audio output.

The control for the system will consist of an on/off switch on the device.

During operation, the device will function automatically. One of the goals of the device is to allow the user

to become more immersed in the television program without being annoyed by commercials. Therefore, the

device will function for the majority of the time without needing any user input.

REQUIREMENTS STATEMENT To allow the design to be applied into daily life and actually lower the amplitude of the commercial signals

which are annoying, the functional requirements need to be set.

The audio leveling device is developed for stabilizing the volume of the commercials relative to the

television program to allow the customers to enjoy consistent volume levels for all the viewing duration. In

other words, the device will make commercials less annoying.

FUNCTIONAL REQUIREMENT Ability to take in an audio signal using RCA stereo cables

Process the input audio signal to obtain a more desirable sound (judged by a poll of potential

consumers)

Output the processed audio signal using RCA cables

Control the output to be either the processed or original signal

Adjust the maximum gain to the modified signal

Make length/width/height of the device a reasonable range so it can be easily carried inside a room

and easily connected to televisions

NON-FUNCTIONAL REQUIREMENT Legal and Regulatory Requirements:

Before the devices are put into the market, it should have passed relative quality and legality test or

certification. However, this audio leveling device, solely being a proof of concept, does not need to

meet these requirements.

Maintainability Requirements:

The device should be encased in a durable shell to avoid being affected by the outside environment

or accidental damage.

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MARKET/LITERATURE SURVEY The customer base for a device similar to this project is quite large; almost everyone is annoyed by loud

commercials at one point or another. There are a few options already on the market that target a similar

customer base. Three competing products were purchased and observed.

The first technology that resembles this problem’s potential solution is Dolby Volume. This is a processor

that can be put in a standalone device, or integrated into a television or a receiver. It debuted in 2008, and

seems to have been quite successful, so this shows there is a profit to be made with this sort of technology.

The Dolby Volume technology is used in an external device called the GefenTV Auto Volume Stabilizer.

The advertisement for this product states, “The GefenTV Auto Volume Stabilizer product is a high-quality

volume stabilizer. It actually makes the volume adjustments in such a subtle way that you won't even notice

the change.”1 This product uses an analog audio RCA cable.

SRS Labs is another company that has produced a similar, but cheaper product. Like Dolby Volume, SRS

Labs has the option of integrating the technology into a television as well as an external device. Brands

already featuring this technology include: Dish Network, EchoStar, Philips, Samsung, Vizio, Numbericable,

and NXP. The technology is advertised to “provide the listener with a comfortable and consistent volume

level…The listener chooses the preferred volume level once and can rest assured it will remain constant.”2

SRS Labs offers this technology in two external device; one with a HDMI cable connection and the other

with an analog connection.

The third product found that resembles this project, is the Terk VR1 Automatic TV Volume Controller. This

is a lower quality and less expensive device than the Dolby Volume and SRS Labs. The Terk is an external

device that is connected from the receiver to the television with RCA connectors. It is describe as “a fully

automatic device that automatically adjusts loudness to proper listening levels.”3

In 2010 the CALM act was passed which is fully in effect starting in 2012. The FCC will regulate television

advertisements to follow a set of given guidelines. Perhaps given these, advertisers will find a new way to

annoy consumers, but that will have to be addressed after the act has been in effect for a few years.

These competing products are to be observed to see how they alter the signal, and determine where the

prototype device will lie in the market. The device will either sound better or be cheaper but still effective.

Either way, according to research, the product will be marketable up until late 2012.

DELIVERABLES

DESIGN SPECIFICATIONS The design specification is a document that will be used by TI to evaluate the plan of action before

production of the prototype begins, and used as an outline for how the device should function.

1 "GefenTV Auto Volume Stabilizer." Gefen, LLC. Web. 31 Oct. 2011.

<http://www.gefen.com/kvm/dproduct.jsp?prod_id=8707>. 2 "TruVolume." SRS Labs: Solutions. Web. 31 Oct. 2011. <http://www.srslabs.com/content.aspx?id=1953>

3 "Terk VR1 Automatic TV Volume Controller." Amazon.com: Online Shopping for Electronics, Apparel, Computers,

Books, DVDs & More. Web. 31 Oct. 2011. <http://www.amazon.com/Terk-VR1-Automatic-TV-Controller/dp/B00008VWOJ/ref=sr_1_1?s=electronics>.

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Inside this document, the operation of the device will be strictly defined. This will list different settings that

could be changed on the device and their intended uses. For example: ‘The device can be enabled and

disabled by setting the ENABLE bit to 1’. Additionally, the design specification will describe how the audio

processor will function. This will include listing expected input signals and desired output signals.

Operating constraints and performance specifications will also be detailed in this document. These

performance specifications will ensure that the audio processor has the necessary characteristics that make it

compatible with a high quality TV. These constraints will be rigidly defined and may include topics such as

maximum power usage, maximum difference in delay between the audio and video, results of blind listening

tests, and cost.

Once a draft of the design specification has been completed, it will be submitted to TI for evaluation and

revision. In this way, the aspects of the design may be evaluated by the customer before production of the

prototype begins. The ultimate goal of this document is to define the characters of the design to ensure that

the delivered product is successful.

ENGINEERING REPORT The Engineering Report is a document for the client (Texas Instruments) that will be used to describe the

different methods and techniques used to solve the problem. This will include justification and description of

the type of implementation chosen. By describing the problem and the approach taken to solving the

problem, it will show that the implemented solution is the best. This report will refer to the constraints and

operations outlined in the design specification document. In this report, the results of the blind listening tests

will be described. Blind listening tests will objectify the subjective ‘annoyingness’ of commercials and show

user satisfaction with the device.

The Engineering report will also have a recommended path for improvements that can be made. This will

include ways to get better performance out of the device and a direction that further research should take as

well. Additionally, ways to lower the cost of production will included in this report.

OPERATING PROTOTYPE The operating prototype will be an audio processor with amplitude-leveling capability. It will be some form

of integrated circuits and digital logic that will have practical inputs and outputs allowing for various types

of signals to be passed through to speakers.

Once constructed, the prototype will be tested against the design document to ensure that it meets all of the

given constraints and has all the necessary features. The operating prototype will be used to perform blind

listening tests and the results will be included in the engineering report.

WORK PLAN

WORK BREAKDOWN STRUCTURE

RESEARCH 35%

An essential part of designing a successful audio processor is understanding what commercials are doing to

garner attention. By fully understanding the techniques used by commercials, an effective design solution to

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mitigate them can be obtained. This includes recording and identifying examples of commercials that will

be used in the blind test. Even more essential is defining what an ‘annoying’ signal truly is, so it can be

eliminated anywhere the characteristic is found.

DESIGN 20%

After identifying the annoyances of commercials, a system can be designed to remove the objectionable

characteristics. This may include filters, automatic gain controls, and non-linear compressing.

IMPLEMENTATION 20%

Once the desired audio processing algorithm is obtained, a method of physically constructing it can be

chosen. This will depend heavily on the different signal processing designed. For example, a non-linear

filter is significantly more difficult to implement in an analog system, so a digital solution would be pursued.

BLIND TESTING 10%

This will involve playing commercials and regular TV programming for a blind audience and evaluating the

performance of our implementation.

DEBUGGING/VALIDATION 15%

In this section, our design and implementation will be evaluated to make sure it works as desired and meets

the characteristics outlined in the design specification.

Figure 4. Work Breakdown Structure

RESOURCE REQUIREMENTS Access to information regarding commercial audio techniques

o This includes the internet, journal articles on audio manipulation, interviews with experts in

the field: professors in the journalism college or employees at a television station.

Information regarding completive productions

Research

Design

Implementation

Blind Testing

Debugging/Validation

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o Limited information is publically available through the manufacture’s website, thus

alternative methods need to be identified such as purchase or reverse engineering of one or

two competitors.

Access and ability to record TV streams including audio and video

o Importing audio streams into Matlab or some other audio processing software, such as

Audacity, to evaluate and test different filters is needed.

Audio processing programs (Audacity)

o Once the audio streams have been recorded, they need to be imported into Audacity so that

the characteristics of the signals may be evaluated. The application of different design

aspects should tested in the software so that potential solutions can be evaluated without

implementation.

Integrated circuits to implement the design

o These could be digital or analog depending on the final design. Once a concept is finalized,

a way to execute it in real-time to perform blind testing and evaluate the effectiveness is

needed.

A sample of blind test subjects to participate in trials once the prototype audio processor has been

designed

o There will have to be enough to give a statistically significant estimate of the effectiveness

of the product. A good sample group would represent a wide range of ages, as well as

technological backgrounds.

A quiet environment where blind testing can take place without being corrupted by external noises

PROJECT SCHEDULE To keep the team more organized and driven, milestones have been established in a Gantt chart format. This

allows members to easily see where a given task stands; where it is in terms of date, and what to what degree

it has been completed. Microsoft Project can be used to gradually change the completion rate of a job,

allowing for an easy showcase of where the group itself stands, and if more time needs to be spent on a task

to ensure it is completed.

The layout for the schedule of the first and second semester of the project is shown below in Tables 1 -2 and

Figures 5-6.

Table 1. First Semester Schedule

Task Name Duration Start Finish % Complete

Meet With Advisor

1 day Tue 8/30/11 Tue 8/30/11 100%

Research

Competetive Products

15 days Tue 8/30/11 Mon 9/19/11 100%

Research Commercial

Techniques

41 days Tue 8/30/11 Tue 10/25/11 100%

Record Commercials

41 days Tue 8/30/11 Tue 10/25/11 100%

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Establish

Contact with TI 56 days Mon 9/19/11 Sat 12/3/11 100%

First Draft of Project Plan

15 days Tue 9/27/11 Mon 10/17/11 100%

First Draft Of

Design Spec 12 days

Mon

10/17/11 Tue 11/1/11 100%

Analyze Commercials in

Database

4 days Tue 11/29/11

Fri 12/2/11 100%

Complete Blind Tests and

Analysis of Competing Devices

6 days Wed 11/30/11

Wed 12/7/11 100%

Create Working

MATLAB Program

34 days Tue 11/1/11 Fri 12/16/11 75%

Complete Final

Design Document and

Project Plan

6 days Mon 11/28/11

Mon 12/5/11 100%

Prepare Final Presentation

7 days Mon 11/28/11

Tue 12/6/11 100%

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Table 2. Second Semester Schedule

Figure 6. Second Semester Ganntt Chart of Schedule

WORK BREAKDOWN The breakdown of each team member’s contribution for the first semester of the project is summarized in

Table 3.

Table 3. Team's contribution

Team

Member Documents

Competitive

Devices

Research Programming Website Recordings Presentations Meetings Total

Max 7 7 10 2 0 7 3 30 66

Morgan 10 0 10 2 0 10 3 30 65

Matt 8 7 10 1 15 2 3 30 76

10

Brian 7 5 5 20 0 3 1 30 71

Amy 7 3 10 1 0 2 3 30 56

Total 39 22 43 28 15 24 13 150 334

RISKS Subjectivity of blind testing

Backlash from TV stations/advertising companies

Similarity to existing audio processors

REFERENCES

"GefenTV Auto Volume Stabilizer." Gefen, LLC. Web. 31 Oct. 2011.

<http://www.gefen.com/kvm/dproduct.jsp?prod_id=8707>.

"TruVolume." SRS Labs: Solutions. Web. 31 Oct. 2011. http://www.srslabs.com/content.aspx?id=1953

"Terk VR1 Automatic TV Volume Controller." Amazon.com: Online Shopping for Electronics, Apparel,

Computers, Books, DVDs & More. Web. 31 Oct. 2011. <http://www.amazon.com/Terk-VR1-

Automatic-TV-Controller/dp/B00008VWOJ/ref=sr_1_1?s=electronics>.