TRANSCODER AND RECEIVER

• US 20090177952A1
• Filed: 06/17/2008
• Published: 07/09/2009
• Est. Priority Date: 01/07/2008
• Status: Abandoned Application

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Maeda, Shinji, YOKOSATO, Junichi
• Application Number:
  US12/140,666
• Publication Number:
  US 20090177952A1
• Time in Patent Office: Days
• US Class Current: 714/799
• CPC Class Codes: H04N 19/174 the region being a slice, e.g. a line of blocks or a group of blocks
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/89 involving methods or arrangements for detection of transmission errors at the decoder
• CPC Class Codes: H04N 21/234309 by transcoding between formats or standards, e.g. from MPEG-2 to MPEG-4 or from Quicktime to Realvideo conversion of standards in analog television systems H04N7/01
• CPC Class Codes: H04N 21/23608 Remultiplexing multiplex streams, e.g. involving modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/2381 Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/2404 Monitoring of server processing errors or hardware failure error or fault detection G06F11/07; monitoring in general G06F11/30
• CPC Class Codes: H04N 21/6379 directed to encoder , e.g. for requesting a lower encoding rate

Abstract

An error extracting unit 7 detects that an error has occurred in a medium stream received, and determines the position of the occurrence. An error specific information adding unit 13 adds error specific information indicating that the error has occurred before the transcoding to an access unit on which the transcoding has been performed, the access unit corresponding to the medium stream in which the error has occurred at the time of the reception.

Claims

1. A transcoder which transcodes a medium stream which said transcoder has received from one network, and sends out the transcoded medium stream to another network, said transcoder comprising:

an error extracting unit for detecting occurrence of an error in said medium stream received, and for determining a position of the occurrence; and

an error specific information adding unit for adding error specific information indicating that the error has occurred before said transcoding to an access unit on which said transcoding has been performed, said access unit corresponding to the medium stream in which the error has occurred at a time of the reception.

2. The transcoder according to claim 1, wherein said error specific information adding unit adds the error specific information in units of each smallest unit to be coded.

3. The transcoder according to claim 1, wherein said error specific information adding unit adds the error specific information into an RTP packet header.

4. The transcoder according to claim 1, wherein said error extracting unit specifies identification information about said transcoder itself when detecting occurrence of an error, and said error specific information adding unit adds the identification information about said transcoder itself which is specified by said error extracting unit.

5. The transcoder according to claim 1, wherein said transcoder includes an error specific information adding position selecting unit for selecting a layer to which the error specific information is to be added on a basis of information for setting up the layer to which said error specific information is to be added, and said error specific information adding unit adds the error specific information to the layer selected by said error specific information adding position selecting unit.

6. The transcoder according to claim 5, wherein said transcoder includes an error specific information setting receiving unit for receiving the information for setting up the layer to which the error specific information is to be added, and said error specific information adding position selecting unit selects the layer on a basis of the information received by said error specific information setting receiving unit.

7. A receiver which receives a medium stream via a network and plays back the medium stream, wherein said receiver comprises an error specific information extracting unit for detecting error specific information included in said medium stream.

8. The receiver according to claim 7, wherein said receiver includes an error display unit for, when said error specific information extracting unit detects the error specific information, displaying an error message indicating that an error exists in the received medium stream on a basis of said error specific information.

9. The receiver according to claim 7, wherein said receiver includes a video display management unit for, when said error specific information extracting unit detects the error specific information, displaying another image which is determined beforehand instead of displaying a part of a video which is specified by said error specific information.

10. The receiver according to claim 7, wherein said receiver includes an error specific information setting communication unit for transmitting information specifying a layer in which the error specific information included in the received medium stream is to be stored.