Audio and Video Development Overview

Audio and video services include audio and video playback and recording.

• The audio/video playback module supports the development of audio/video playback services, including the playback of audio/video files and streams, volume control, and playback progress control.
• The recording module supports the development of audio and video recording services and provides the functions related to audio and video recording, including setting the size of the recorded video picture, sampling rate, encoder type, video frame rate, audio sampling rate, and output format of the recorded file.

It is considered good practice that you understand the following concepts before starting application development:

• Streaming media technology

  The streaming media technology is a technology in which continuous video and sound information is encoded and then stored on a network server, so that a viewer can watch and listen to the video and sound while downloading the video and sound, without waiting for completion of downloading of an entire multimedia file.

• Frame rate

  The frame rate is used to measure the number of displayed frames. The number of frames is the number of images transmitted per second. The more frames per second (FPS), the smoother the image.

• Bit rate

  Bit rate is the number of bits transmitted per unit of time during data transmission. The commonly used unit is kbit/s.

• Sampling rate

  The sampling rate is the number of samples per second taken from a continuous signal to form a discrete signal, expressed in hertz (Hz).