RTP-formated media clips

• US 7,136,577 B1
• Filed: 06/29/2000
• Issued: 11/14/2006
• Est. Priority Date: 06/29/2000
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Tandberg Telecom AS (Cisco Systems, Inc.)
• Inventors: Falco, Michael A.
• Primary Examiner(s): Tran, Thai
• Assistant Examiner(s): Shibru, Helen
• Application Number:
  US09/606,582
• Time in Patent Office: 2,329 Days
• Field of Search: 386/2, 386/33, 386/40, 386/124, 386111-112, 360/8, 360/32, 370/352, 370/354, 370/355, 370/356, 370/377, 370/389, 370/392, 370/395.1, 370/395.52
• US Class Current: 386/330
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/6437 Real-time Transport Protocol [RTP]
• CPC Class Codes: H04N 9/8042 involving data reduction
• CPC Class Codes: H04N 9/877 by assembling picture element blocks in an intermediate memory

Abstract

A transmitter (14) of audio, video, or other real-time information reads the information from a persistent store (22) in which the real-time information has been stored in the Real-time-Transport Protocol (“RTP”) format (FIG. 4). A receiver (18) receives the information from the channel (16) through which the transmitter (14) has transmitted it, and the receiver may store the information in a persistent store (24) in RTP format instead of or in addition to playing it by applying it to an appropriate player (20). Parts of this communications circuit may be tested by a tester unit (26) that also employs RTP-format information from a persistent store (22).

Claims

1. A method of performing persistent storage comprising:

A) receiving a received record containing audio data in received RTP packets, of which each includes a received RTP payload and a respective received RTP timestamp;

B) in response to the received record, extracting information of interest from the headers of the received RTP packets;

C) storing in a persistent medium a stored record as stored packets of which each corresponds to a respective one of the received RTP packets, each stored packet including as the packet payload the RTP payload contained in the respective received RTP packet and further including a header that includes a stored timestamp derived from the corresponding received RTP timestamp in the received RTP packet header; and

D) retrieving the stored record and playing it in accordance with the stored timestamps contained therein by determining the times to play the data contained in the respective stored packets based on a combination of the local time and the stored timestamp contained in the stored packets.

2. A method of performing persistent storage comprising:

A) receiving a received record containing video data in received RTP packets, of which each includes a received RTP payload and a respective received RTP timestamp;

B) in response to the received record, Extracting information of interest from the headers of the received RTP packets;

C) storing in a persistent medium a stored record as stored packets of which each corresponds to a respective one of the received RTP packets, each stored packet including as the packet payload the RTP payload contained in the respective received RTP packet and further including a header that includes a stored timestamp derived from the corresponding received RTP timestamp in the received RTP packet header; and

D) retrieving the stored record and playing it in accordance with the stored timestamps contained therein by determining the times to play the data contained in the respective stored packets based on a combination of the local time and the stored timestamp contained in the stored packets.

3. A method as defined in claim 2 wherein the method additionally includes:

A) receiving a second received record in second RTP packets containing audio data, each second RTP packet including a received RTP payload and a respective received RTP timestamp;

B) in response to the second received record, storing in the persistent medium a second stored record as second stored packets of which each corresponds to a respective one of the second received RTP packets, each second stored packet including the RTP payload contained in the respective received RTP packet and further including a respective stored RTP timestamp derived from the corresponding second received RTP packet'"'"'s received RTP timestamp;

C) retrieving the second stored record; and

D) playing the second stored record simultaneously with the first-mentioned stored record in accordance with the stored timestamps contained in the second stored record by equating the start times of the first and second stored records and determining the times to play the data contained in the respective stored packets of the second stored record based on a combination of the local time and the respective stored timestamps.

4. A method of performing persistent storage comprising:

A) concurrently taking samples of time-dependent video data and audio data;

B) before transmitting or playing back the data, storing a record of the video data in a persistent medium as a plurality of stored RTP packets whose payloads represent the samples'"'"' values and whose stored timestamps represent the times at which the first samples in their respective payloads were taken and storing a second stored record of the audio data in a persistent medium as second stored RTP packets, whose payloads represent the audio samples'"'"' values and whose stored timestamps represent the times at which the first samples in their respective payloads were taken; and

C) playing the second stored record simultaneously with the first-mentioned stored record in accordance with the stored timestamps contained in the second stored record by equating the start times of the first and second stored records and determining the times to play the data contained in the respective stored packets of the second stored record based on a combination of the local time and the respective stored timestamps.

5. For storing time-dependent data, an apparatus comprising:

A) a persistent medium operable to store received data and retrieve data thus stored;

B) a receiver that receives a received record that contains audio data as a plurality of received RTP packets, with each packet including a received RTP payload and a corresponding received RTP time-stamp; and

C) a persistent-store driver that responds to the receiver by extracting information of interest from the received RTP packet headers and storing in the persistent medium a stored record as a plurality of stored packets with each packet corresponding to a respective one of the received RTP packets, each stored packet including the RTP payload contained in the respective received RTP packet and further including a stored timestamp derived from the received RTP timestamp in the header of the corresponding received RTP packet, the persistent-store driver also retrieving the stored record; and

D) an audio player and an audio driver that drives the audio player to play the stored record in accordance with the stored timestamps contained therein by determining the times to play the data contained in the respective stored packets based on a combination of the local time and the stored timestamp contained in the stored packets.

6. For storing time-dependent data, an apparatus comprising:

A) a persistent medium operable to store received data and retrieve data thus stored;

B) a receiver that receives a received record that contains video data as a plurality of received RTP packets, with each packet including a received RTP payload and a corresponding received RTP timestamp; and

C) a persistent-store driver that responds to the receiver by extracting information of interest from the received RTP packet headers and storing in the persistent medium a stored record as a plurality of stored packets with each packet corresponding to a respective one of the received RTP packets, each stored packet including the RTP payload contained in the respective received RTP packet and further including a stored timestamp derived from the received RTP timestamp in the header of the corresponding received RTP packet, the persistent-store driver also retrieving the stored records; and

D) a video player and a video driver that drives the video player to play the stored record in accordance with the stored timestamps contained therein by determining the times to play the data contained in the respective stored packets based on a combination of the local time and the stored timestamp contained in the stored packets.

7. An apparatus as defined in claim 6 wherein:

A) the receiver additionally receives a second received record in second RTP packets containing audio data, each second RTP packet including a received RTP payload and a respective received RTP timestamp;

B) in response to the receiver'"'"'s receiving the second received record, the persistent-store driver extracts information of interest from the headers of the received RTP packets and stores in the persistent medium a second stored record as second stored packets of which each corresponds to a respective one of the second received RTP packets, each second stored packet including the RTP payload contained in the corresponding received RTP packet and further including a header that includes a respective stored timestamp derived from the received RTP timestamp in the header of the corresponding received RTP packet;

C) the persistent-store driver also retrieves the second stored record; and

D) the apparatus further includes an audio player and an audio driver that drives the audio player, simultaneously with the video driver'"'"'s driving of the video player, to play the thus-retrieved second stored record in accordance with the stored timestamps contained therein by equating the start times of the first and second stored records and determining the times to play the data contained in the respective stored packets of the second stored record based on a combination of the local time and the respective stored timestamps.

8. For storing time-dependent data, and an apparatus comprising:

A) a persistent medium operable to store data and retrieve data thus stored;

B) a sampler that produces a sampled record by taking samples of a time-dependent function, the sampled data being audio data;

C) a persistent-store driver that responds to the sampler by storing in the persistent medium a stored record as stored RTP packets whose payloads represent the samples'"'"' values and whose stored timestamps represent the times at which the first samples in their respective payloads were taken, the persistent-store driver also retrieving the stored records; and

D) an audio player and an audio driver that drives the audio player to play the stored record in accordance with the thus-retrieved stored timestamps contained therein by determining the times to play the data contained in the respective stored packets based on a combination of the local time and the stored timestamp contained in the stored packets.

9. For storing time-dependent data, an apparatus comprising:

A) a persistent medium operable to store data and retrieve data thus stored;

B) a sampler that produces a sampled record by taking samples of a time-dependent function, the sampled data being video data;

C) a persistent-store driver that responds to the sampler by storing in the persistent medium a stored record as stored RTP packets whose payloads represent the samples'"'"' values and whose stored timestamps represent the times at which the first samples in their respective payloads were taken, the persistent-store driver also retrieving the stored records; and

D) a video player and a video driver that drives the video player to play the stored record in accordance with the thus-retrieved stored timestamps contained therein by determining the times to play the data contained in the respective stored packets based on a combination of the local time and the stored timestamp contained in the stored packets.

10. An apparatus as defined in claim 9 wherein:

A) the sampler additionally produces a second sampled record by taking audio samples of a sound signal;

B) the persistent-store driver additionally responds to the sampler by storing in the persistent medium a second stored record as stored RTP packets whose payloads represent the audio samples'"'"' values and whose stored timestamps represent the times at which the first audio samples in their respective payloads were taken; and

C) the apparatus further includes an audio player and an audio driver that retrieves the second stored record and drives the audio player to operate simultaneously with the video driver'"'"'s driving of the video player, in accordance with the stored timestamps contained in the second stored record therein by equating the start times of the first and second stored records and determining the times to play the data contained in the respective stored packets of the second stored record based on a combination of the local time and the respective stored timestamps.