Transport demultiplexor with bit maskable filter

• US 20060080110A1
• Filed: 11/14/2005
• Published: 04/13/2006
• Est. Priority Date: 09/13/2000
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Lloyd, Bryan J., Foster, Eric M., Franklin, Dennis E.
• Granted Patent: US 7,675,876 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: E01F 9/654 in the form of three-dimensional bodies, e.g. cones; capable of assuming three-dimensional form, e.g. by inflation or erection to form a geometric body
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/4341 Demultiplexing of audio and video streams
• CPC Class Codes: H04N 21/4347 Demultiplexing of several video streams
• CPC Class Codes: H04N 21/4385 Multiplex stream processing, e.g. multiplex stream decrypting
• CPC Class Codes: H04N 7/163 by receiver means only

Abstract

The preferred embodiment of the present invention provides an improved transport demultiplexor that can receive and filter different data types before sending the data to system memory. The preferred embodiment provides a string comparator to facilitate real time filtering of continuous incoming data before loading the data into system memory. The string comparator preferably uses a bit-maskable matching filter that filters system data in real time as the data is being delivered to system memory. When data matching the filter is located, the destination address of that data is determined and delivered to the processor. This allows the processor to quickly locate the desired data and thus facilitates the real time processing of that data.

Claims

1. A transport demultiplexor, the transport demultiplexor selectively receiving a transport stream, the transport demultiplexor delivering transport stream data to a data unloader, and wherein the transport demultiplexor includes a string comparator, the string comparator comparing transport stream data from the data unloader to at least a portion of the compare value filter and storing a destination address of the transport stream data when the compared transport stream data matches the at least a portion of the compare value filter.

2. The transport demultiplexor of claim 1 wherein the string comparator includes a compare register, wherein the compare register stores the at least one compare value filter

3. The transport demultiplexor of claim 2 wherein the compare register receives the compare value filter from a system processor.

4. The transport demultiplexor of claim 2 wherein the compare register stores a plurality of compare value filters, with each of the compare value filters compared to transport stream data corresponding to a different memory queue.

5. The transport demultiplexor of claim 1 wherein the string comparator includes a masking register and wherein the masking register includes at least one masking filter, wherein the at least one masking filter determines the at least one portion of the compare value filter that is compared to the transport stream data.

6. The transport demultiplexor of claim 5 wherein the masking register receives the at least one masking filter from a system processor.

7. The transport demultiplexor of claim 1 wherein the string comparator includes an address register and wherein the address register stores the destination address of matching transport stream data.

8. The transport demultiplexor of claim 7 wherein the address register stores a plurality of destination addresses in a first-in-first-out buffer.

9. The transport demultiplexor of claim 1 wherein the transport stream comprises an MPEG-2 transport stream.

10. The transport demultiplexor of claim 1 wherein the string comparator notifies a system processor when the compared transport stream data matches the at least a portion of the compare value filter.

11. A transport demultiplexor for receiving a transport stream, the transport demultiplexor comprising:

a) front end logic;

b) a packet buffer;

c) a video unloader;

d) a data unloader;

e) an audio unloader, and wherein said front end logic receives the transport stream and delivers the transport stream to the packet buffer, and wherein said packet buffer delivers selected transport stream video data to the video unloader and selected transport audio data to the audio unloader, and wherein the said packet buffer delivers other transport stream data to the data unloader for delivering to system memory; and

f) a string comparator, the string comparator including;

i) a compare register, the compare register storing at least one compare value filter;

ii) a masking register, the masking register designating at least a portion of the compare value filter;

iii) an address register; and

wherein the string comparator compares the other transport stream data from the data unloader to the designated at least a portion of the compare value filter and stores a destination address of the other transport stream data at the address register when the compared other transport stream data matches the designated at least a portion of the compare value filter.

12. The transport demultiplexor of claim 11 wherein the compare register receives the compare value filter from a system processor.

13. The transport demultiplexor of claim 11 wherein the compare register stores a plurality of compare value filters, with each of the compare value filters compared to system data corresponding to a different memory queue.

14. The transport demultiplexor of claim 11 wherein the masking register receives the at least one masking filter from a system processor.

15. The transport demultiplexor of claim 11 wherein the address register stores a plurality of destination addresses in a first-in-first-out buffer.

16. The transport demultiplexor of claim 11 wherein the front end logic includes a bypassable packet parser, the bypassable packet parser receiving a first and second type of transport stream from the bypassable synchronizer, the bypassable packet parser filtering the first type transport stream data before passing to the packet buffer, the bypassable packet parser delivering second type transport stream data to the packet buffer without filtering.

17. The transport demultiplexor of claim 11 wherein the data unloader includes a queue control, said queue control controlling storage location of said first transport stream system data in system memory.

18. The transport demultiplexor of claim 11 wherein the transport stream comprises an MPEG-2 transport stream.

19. The transport demultiplexor of claim 11 wherein the string comparator notifies a system processor when the compared other transport stream data matches the designated at least a portion of the compare value filter.

20. A transport demultiplexor for receiving MPEG-2 transport stream, the transport demultiplexor comprising:

a) a packet buffer;

b) front end logic, the front end logic selectively receiving the MPEG-2 transport stream and the alternative transport stream, the front end logic comprising;

i) a synchronizer, the bypassable synchronizer receiving the MPEG-2 transport stream;

ii) a packet parser, the bypassable packet parser selectively receiving the MPEG-2 transport stream, wherein the packet parser retrieves identification information from transport stream packets, and wherein the packet parser retrieves identification information from the MPEG-2 transport stream and appends packet identification from the retrieved identification information to the MPEG-2 transport packets, the appended packet identification used identify the MPEG-2 transport stream packets as video packets, audio packets or system data packets;

c) a video unloader, the video unloader receiving selected MPEG-2 video packets from the packet buffer;

d) an audio unloader, the audio unloader receiving selected MPEG-2 audio packets from the packet buffer;

e) data unloader, the data receiving MPEG-2 system data packets and other transport stream data packets, the data unloader delivering the MPEG-2 system data packets and other transport stream data packets to system memory as system memory data for processing; and

f) a string comparator, the string comparator including;

i) a compare register, the compare register storing at least one compare value filter;

ii) a masking register, the masking register designating at least a portion of the compare value filter;

iii) an address register; and

wherein the string comparator compares system memory data from the data unloader to the designated at least a portion of the compare value filter and stores a destination address of the system memory data at the address register when the compared system memory data matches the designated at least a portion of the compare value filter.