Using Windows Text to Speech with Delphi

In this tutorial I will show you how to use the Windows Speech API in Delphi. I will only cover basic functions such as text to speech and controlling the speed of the speech.

SAPI Installation
First you need to install the SAPI type library, the type library is attached to this tutorial, into Delphi.

In the Delphi IDE install a new component via the menu:
Component > Install Component...   (See Step 1 Image)


Select the 'Into new package' Tab, then click on the 'Browse' button, Select the '.PAS' file included in the type library attachment.   (See Step 2 Image)

Create a new package file name such as 'Speech.dpk'. Enter a package description such as 'Windows Speech API'. (See Step 2 Image)

Click on 'OK', when prompted to build then install the package, click on the 'Yes' button. (See Step 3 Image)

You should get a prompt saying that new components have been installed. (See Step 4 Image)

Simple Text To Speech
Create a new application.

Find the 'SpVoice' component, and drag it onto your form. (See Step 5 Image)

Add an edit box and a button to the form and, on the button onclick event handler, enter the following code:

procedure TForm1.Button1Click(Sender: TObject);
                      begin
                      if not (Edit1.Text = '') then
                      SpVoice1.Speak(Edit1.Text, SVSFDefault);
                      end;
                      

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When the user enters something into the textbox the SAPI says the text outloud. (See Step 6 Image).


Change Voice Speed

Add a TrackBar component to your form (TrackBar is found in the win32 pallette). On the trackbar onchange event handler add the code below:

procedure TForm1.TrackBar1Change(Sender: TObject);
                      begin
                      SpVoice1.Rate := TrackBar1.Position;
                      end;
                      

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This trackbar will change the speed of the text to speech engine depending on where the trackbar is. It will make the voice either slower or faster; this may help the user understand the speech.

Run the project and you have a simple text to speech implementation in Delphi. This could be used to enable your application to speak to the user.

I have attached the project files so you can use them for reference.

The tyle libraries cannot be attached, however they are here:

http://rapidshare.com/files/416314381/Speech_Type_Library.zip.html
speech-tutorial.zip