Abstract: A method for providing audio-only recording is disclosed. According to the method, a combined video stream and an audio stream are received from a source. The audio stream is digitized, if in analog form. The digitized audio stream is compressed using an audio encoding engine. The encoded audio stream is saved in a storage device. The storage device can be local or on a network. In the case of the input A/V signal being a multiplexed and compressed digital signal, the audio segment(s) are separated using a demultiplexer and saved in a storage device. The encoding format of the stored audio data follows that of the original audio data embedded in the multiplexed A/V stream. To store the audio data in a different encoded format, the audio data is first decoded using an appropriate audio decoder and then re-encoded in the desired encoding format. Alternatively, an audio transcoder can be used to store the audio data in the desired encoding format.

Abstract: A method for displaying video data instantly in reverse order is disclosed. According to the method, a compressed audio and video (A/V) stream is received from a source. The compressed A/V stream is demultiplexed into an audio stream and a video stream. The video stream has a number of compressed video frames which include a number of key frames. Each key frame is followed by one or more associated frames. Each of the compressed video frames is tagged with a tag. The tag associated with each key frame and file position of each key frame is stored in a table. The compressed video frames are decoded to generate a number of decoded video frames while maintaining their corresponding tags. During normal play, the decoded video frames are stored in a forward queue, and the decoded video frames in the forward queue are then outputted in a FIFO (first-in-first-out) order to a reverse queue and a display device for display.