The components which are needed to accomplish this project are

HardWare components 

1 . Raspberry Pi 3

2. Camera module (compatible with Raspberry Pi)

3. Speaker

4.LCD module

5. Mic

SoftWare components

 1. OpenCV

2. Text to Speech application (TTS)

3 . Speech to Text application

Working

1 . Camera

Camera acts as an input device for SLT which captures the sign and transfer corresponding images to Raspberry Pi , the brain . 

2 . Microphone

 Microphone also acts as an  input device for SLT which captures the sound and transfer it to the brain .

3 . Raspberry Pi

Raspberry Pi act as the brain of the entire device and it perform different types of function depending on the three modes of operation of this device .

1 . SIGN to SPEECH Translation mode

  This is the mode which is used when a speech impaired man communicates with a common man . In this mode the camera snap the gestures and the corresponding images are transferred into Raspberry Pi . The OpenCV library installed on the Raspberry Pi processes the image and produce a corresponding text output , which is made to speech using a Text to Speech application . 

2 . SIGN to TEXT Translation mode

  This is the mode which is used when a speech impaired man communicates with a hearing impaired man . In this mode the camera snap the gestures and the corresponding images are transferred into Raspberry Pi . The OpenCV library installed on the Raspberry Pi processes the image and produce a corresponding text output , which is displayed on the LCD module .

3 . SPEECH to TEXT Translation mode

 This is the mode which is used when a common man communicates with a hearing impaired man . In this mode the microphone records the sound and is transferred into Raspberry Pi . Using a Speech to Text application the sound is converted into text and is displayed on the LCD module .

4 . Speaker

It acts as an output device which produce sound output according to the signals from the brain .

5 . LCD MODULE

It also acts as an output device which produce text output according to the signals from the brain .

6 . OpenCV

 It is the core where actual function of translation takes place . OpenCV is a real time computer vision library with strong processing efficiency . OpenCV processes the image captured by camera on various approaches

1. Template Based Approaches    

Unknown speech is compared against a set of pre-recorded words (templates) in order to find the best match. 

2.Knowledge Based Approaches  

An expert knowledge about variations in speech is hand coded into a system.   

3.Statistical Based Approaches   

In which variations in speech are modelled statistically, using automatic, statistical learning procedure.  

4.The Artificial Intelligence Approach   

The artificial intelligence approach attempts to mechanize the recognition procedure according to the way a person applies its intelligence in visualizing, analyzing, and finally making a decision on the measured acoustic features.

We are using template based approaches and in future versions another approaches may be used .

7 . Text to Speech application

It is used to convert the text output produced by OpenCV to speech .

8 . Speech to Text application 

 It is used to convert the speech input  into text output .

The flow of data is as shown below

Through this project I want to empower all those who are in need of such a device and dedicate this to my dear friend. Also I hope this project can be made into a device with all your support. Support me by liking my project. Helpful comments and suggestions are welcomed.