| | Category | CS | P05 | How do Pitch and Speed Affect Voice Recognition? |
| | Abstract | The purpose of this experiment was to find out how much the speed and |
| | pitch of a voice would have to be changed until the voice could no longer |
| | be recognized by computer speech recognition software. The voice was |
| | recorded speaking a command for the computer using Audacity digital |
| | audio editor. Windows speech recognition was used; it is a program |
| | where you can speak into a microphone and it interprets your voice and |
| | carries out the computer command your voice is speaking. The voice was |
| | then sped up and slowed down and tested for accuracy in carrying out |
| | the command at different percents above and below the normal speed. |
| | The voice was also raised and lowered in pitch and tested. The variables |
| | of pitch and speed were then both changed at the same time and tested. |
| | The data for the combination of variables was plotted on a success/failure |
| | graph. The results showed that the voice was recognizable up to 17% |
| | increased speed, 21% decreased speed, 27% raised pitch, or 20% |
| | lowered pitch. When the variables were combined, as the pitch was |
| | raised, the speed needed to be lowered for the voice to be recognized |
| | and vice versa. From this we can conclude that speed has a greater |
| | impact on the recognition of a voice than pitch and that speed and pitch of |
| | a voice are inversely related. |
| | Bibliography | 1. "Audacity - Effect Menu." Audacity: Free Audio Editor and |
| | Recorder. N.p., n.d. Web. 11 Mar. 2010. |
| | <http://audacity.sourceforge.net/onlinehelp-1.2/menu_effect.htm>. |
| | 2. "Audacity: About Audacity." Audacity: Free Audio Editor and |
| | Recorder. N.p., n.d. Web. 21 Feb. 2010. |
| | <http://audacity.sourceforge.net/about/>. |
| | 3. "How To Use Speech Recognition in Windows XP." Microsoft |
| | Support. N.p., n.d. Web. 11 Mar. 2010. |
| | <http://support.microsoft.com/kb/306901>. |
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