Speech Recognition, The process of taking spoken word as an input to a computer

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1 Speech Recognition, The process of taking spoken word as an input to a computer program (Baumann) Have you ever found yourself yelling at your computer, wishing you could make it understand what you want it to do? Or find yourself envious of those old science fiction films like Star Trek, where they just told the computer what they wanted and it responded to them appropriately? Then you need to try speech recognition. No, you can t really communicate fluidly with your computer but it may seem close to it after you get the hang of using it. Speech recognition has been around since 1952, these devices only recognized single digits. In 1964 at the New York World s Fair, IBM displayed their IBM Shoebox, called so because it was the size and shape of a typical shoebox of those days. The Shoebox had ten lights on it that lit up when a given number was spoken into the microphone. The key to this device was that each number had a given sound pitch at the beginning, middle and end. For example the number 5 is High-Middle-High. When the number was stated into the microphone the sound would pass through filters that decoded the given response and then turn on one of the lights. (Wickpedia) There are two basic types of speech recognition used today, Template matching and Feature analysis. Template matching is similar to that used in the IBM Shoebox; it is very accurate but also very limiting. When a command is spoken the program attempts to match it with a sample or template that has a preprogrammed meaning assigned to it. The computer then carries out the given assignment. The computer is able then to use this input in a similar manner to that of inputs from a keyboard. (Baumann). 1

2 Every person s voice is different so the computer must first be trained to recognize a user s voice pattern. This is done through training sessions. In these sessions the user is given a set phrase to read, sometimes even repeatedly. The computer then gathers this information and stores an average speech pattern for the words and phrases that you have spoken. This will limit the use of the program to those who have trained on that computer, and to the vocabulary or patterns used in that training. This is known as speaker dependent and gives the computer a limited vocabulary with an accuracy of about 98%. (Baumann) With Feature analysis speaker-independent voice recognition is better achieved. In this method the computer tries to find a near match of the speech input with a previously stored template. To do this it first runs the input through Fourier transformers or linear predictive coding (LPC), it then looks for similarities between the input and the voice templates it has stored in its files. These similarities are present in a wide range of people so each individual user doesn t need to train the computer to their own voice commands. However this method isn t always able to compensate for different accents, speech impediments, or nationalities. That makes this system a little less reliable, usually with the success rate of 90%-95%. (Baumann) Other difference between the different systems on the market is their ability to handle continuous speech. Most systems are Discrete word systems, since they are the easiest to set up. With this system the user must pause briefly between each word, which is fine for one word inputs, but not very natural to the user when they are entering multiple word inputs. Other systems use Connected word voice recognition, with this system the user may use multiple word inputs but still must articulate each word carefully. The easiest system for a user to use, but the hardest to implement is continuous speech. This system allows for continuous more natural speech. (Baumann) 2

3 Today, speech recognition is becoming more widely used. Most of us have paid bills or dealt with automated computer phone operators. Often these operators give the user a choice between verbal responses or by pushing keys on the phone number pad. If you have had the chance to use one of these systems then you may know how frustrating it can be. Despite this many find using the voice response more friendly and convenient. The health care community is also interested in using it more, however at this time they haven t been able to do away with transcriptionist jest yet. The military uses it today in many ways including on some of the High performance aircraft. This though has been limited and not always reliable. Probably the most potential and most obvious place that we can use this technology is with helping the disabled, especially those who have difficulty using their hands, whether it is from some major disability or just from those with repetitive motion injuries (carpal tunnel). (Answers.com) Since you can talk faster than you can type, speech recognition s potential for increased production makes using it practical for everyone. However until recently, speech recognition had been a little cumbersome to use. It was inaccurate and slow to respond especially when used to navigate the web. With recent changes though, it has become a powerful tool. (Pavlina) Getting started with speech recognition is easy. Up until recently Dragon Naturally Speaking was the best software on the market when it came to ease of use and availability. However Microsoft has been working on their own version of speech recognition and has now made it available on all Vista and Windows 7 Operating systems. Consumer reports show that Windows speech recognition is as good if not better in some areas than Dragon Naturally speaking and is much cheaper since it is already installed if you are running Vista or Windows 7. However for professional use Dragon Naturally speaking is still recommended simply because it has a larger vocabulary and often inserts punctuation automatically. (Consumer search) 3

4 To get started you will want to make sure your system is fast and powerful. It is recommended that you use a least, a 2.4 GHz Pentium III/IV Processor, a 16 bit sound card, 40 GIG or higher hard drive, 1 GIG ram and a high quality Microphone. (Everton) For this project I have been using Microsoft speech recognition on Vista. To activate the program go to your control panel, and click on speech recognition. At this point you can click on Start speech recognition; this will activate the software and take you through the setup and training. It is important for you to complete the speech tutorial as this will not only train you but the program as well. Once set up just begin using it and try to have fun with it, and not to get to discouraged, it may take time for you to get used to it and it to you. Begin by printing out a list of commands. The software has an extensive list of them. These commands are what you must say when you want the program to respond in any manner. Also you will see an icon at the top of the page. When speech recognition is not being used, it will state Sleeping, to begin just say start listening, then the microphone lights up, and every time you talk the graph next to the microphone will show the level of hearing and understanding. First try using it to dictate. You can begin by opening either note pad, Microsoft word, or any other word processer. You will have to place all punctuation by stating the proper command at the right point. For instance you must end all sentences by saying: Period, Dot, Full stop, or Decimal point. I have found that adding in the punctuation is probably the most troublesome thing for me, followed close by correcting errors. If you come across a word that the program doesn t recognize you can spell it out by saying press and then the letter you want. This is rarely a problem though unless it is a proper name. 4

5 As a way of demonstrating the dictation method, I am dictating this paragraph through speech recognition. I find this to be very easy to use. However I do, so making a lot of corrections these corrections take much time to work out. And I am not making all the corrections to say you can see some errors that it may make. However, for the most part using dictation what methods seems to work fairly well. You may also use speech recognition to navigate around your computer and navigator on the web. As I have demonstrated in the above paragraph Speech Recognition doesn t always hear what you think you said. This results in having to go back and make corrections. You shouldn t get too worked up over this though since the more corrections you make the better the program learns to understand you, eventually you will learn how to use it better and it will get better at understanding you. Navigating around your computer and around the web may seem to be a little less productive. Navigation can be done by saying show numbers; the program then shows numbers over all the different buttons on the active window screen. You then state the number of the button you wish to use and say, click, double click, or right click, to get the desired result. Another method for navigation is to say show mouse grid. This brings up a grid of 9 numbers you then state which number contains the button or icon you wish to activate, the program responds by showing another grid but just in the area of the number stated. You will continue doing this till the grid covers just the area 5

6 you wish to click on. You may then state the operation you wish to occur. The last method you will use is to state what you see. For instance if your active desk top showed something like this, you may open your by just stating Mail, or you could open your favorites list by stating Favorites. I have found that navigating the web in this manner isn t very productive and I usually give up on it. Speech recognition has come a long ways over the years and is finally becoming a practical tool to use. In the coming years it will only get better and more productive. Answers.com. Answers.com < Baumann, Jim. Voice recognition. 14 feb 2010 < Consumer search. Windows Speech Recogniton < Everton. Windows 7 & 8 Forum < news/latest-windows-7-news-looking-at-speech-recognition-part-2/>. Pavlina, Steve. Voice Recogniton Software < Wickpedia. Answers.com < 6

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