STREAM ANALYSIS APPARATUS AND STREAM ANALYSIS DISPLAY METHOD

• US 20090122714A1
• Filed: 05/09/2008
• Published: 05/14/2009
• Est. Priority Date: 05/11/2007
• Status: Active Grant

• Current Assignee: Tektronix Incorporated (Fortive Corp.)
• Original Assignee: Tektronix Incorporated (Fortive Corp.)
• Inventors: KATO, YOSHIAKI
• Granted Patent: US 7,835,403 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04N 17/004 for digital television systems
• CPC Class Codes: H04N 21/4305 Synchronising client clock from received content stream, e.g. locking decoder clock with encoder clock, extraction of the PCR packets arrangements for synchronising receiver with transmitter by comparing receiver clock with transmitter clock H04L7/0012; arrangements for synchronising receiver with transmitter wherein the receiver takes measures against momentary loss of synchronisation H04L7/0083
• 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 21/44209 Monitoring of downstream path of the transmission network originating from a server, e.g. bandwidth variations of a wireless network arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896

Abstract

An analysis display GJ1 has a coordinate plane of which coordinate axes are elapsed time and PCR (Program Clock Reference) time calculated using PCR extracted from header information of a transport stream packet. A box indicator representing an access unit is provided on the coordinate plane and sides of the box indicator indicate an arrival time of the access unit AU and time of time stamps PTS/DTS. It analyzes the PCR in a transport stream layer and the time stamps PTS/DTS in a PES layer in a manner of over layers, and displays an analysis result that allows easily understanding a relationship between system timing and them. Therefore, it makes it easier to check a problem on the PCR and the time stamps PTS/DTS.

Claims

1. A stream analysis apparatus comprising:

packet header extracting means for extracting header information from a transport stream packet;

time stamp extracting means for extracting a time stamp from the transport stream packet;

clock generation process means for generating a clock signal as a reference of presentation timing of content data transmitted by the transport stream packet; and

analysis process means for analyzing an access unit transmitted by the transport stream packet using a PCR (Program Clock Reference) extracted by the packet header extracting means, the clock and the time stamp wherein the analysis process means generates a display signal for displaying an analysis result having a box indicator representing the access unit on a coordinate plane of which axes are elapsed time and PCR time calculated using the PCR to indicate an arrival time of the access unit and a time of time stamp by the sides of the box indicator.

2. The stream analysis apparatus as recited in claim 1 wherein the analysis process means provides the box indicator so as to identify that the data of the access unit is which type of picture among intraframe predictive coding, interframe predictive coding and bidirectionally predictive coding.

3. The stream analysis apparatus as recited in claim 1 wherein the analysis process means provides a PCR indicator based on the arrival time of the PCR and the PCR time in the analysis result display.

4. The stream analysis apparatus as recited in claim 1 wherein the analysis process means identifies the transport stream packets using PIDs (Packet Identifier) extracted by the packet header extracting processor means, and provides indicators of arrival times of the transport stream packets with respect to each PID on the elapsed time as a coordinate axis in the analysis result display.

5. The stream analysis apparatus as recited in claim 1 further comprising packet extracting means for extracting a packet of TOT (Time Offset Table) or TDT (Time and Data Table) from the transport stream packet wherein the analysis process means links a coordinate axis representing time based on present time provided by the TOT or TDT extracted by the packet extracting means and the coordinate axis for indicating the arrival time.

6. The stream analysis apparatus as recited in claim 1 further comprising user interface process means wherein the analysis process means provides the analysis result display with an information display on an access unit that is selected by selecting a box indicator representing the access unit with the user interface process means.

7. The stream analysis apparatus as recited in claim 1 further comprising:

decoding process means for decoding the access unit;

display process means for combing the analysis result display and display of a decoded result of the decoding process means; and

user interface process means wherein when an access unit is instructed to be presented with the user interface process means, the decoding process means decodes the instructed access unit, and the instructed access unit is displayed so as to be identified in the analysis result display.

8. A stream analysis display method for a stream analysis apparatus analyzing a transport stream, comprising steps of:

providing a coordinate plane of which coordinate axes are elapsed time and PCR time calculated using PCR (Program Clock Reference) extracted from header information of a transport stream packet; and

providing a box indicator representing an access unit on the coordinate plane wherein sides of the box indicator indicate an arrival time of the access unit and time of time stamp.

9. The stream analysis display method as recited in claim 8 wherein the box indicator is provided so as to identify that the data of the access unit is which type of picture among intraframe predictive coding, interframe predictive coding and bidirectionally predictive coding.

10. The stream analysis display method as recited in claim 8 wherein a PCR indicator is provided based on an arrival time of the PCR and the PCR time in the analysis result display.

11. The stream analysis display method as recited in claim 8 further comprising a step of identifying the transport stream packets using PIDs (Packet Identifier) included in the header information for displaying arrival times of the transport stream packets with respect to each PID on the elapsed time as a coordinate axis.

12. The stream analysis display method as recited in claim 8 further comprising a step of displaying a coordinate axis of time based on present time provided by a packet of TOT (Time Offset Table) or TDT (Time and Data Table) extracted from the transport stream packet wherein the coordinate axis of the time is linked with the coordinate axis for indicating the arrival time.

13. The stream analysis display method as recited in claim 8 further comprising a step of displaying information on an access unit that is selected by selecting a box indicator representing the access unit.

14. The stream analysis display method as recited in claim 8 further comprising a step of displaying a decoded result of an access unit when the access unit is instructed to be presented.