Method and apparatus for packet transmission
First Claim
1. A method of transmitting a packet string with various packet intervals wherein an original packet string as said packet string with various packet intervals is transmitted from a transmitting side after being converted into a packet string with substantially fixed packet intervals comprising the steps of:
- calculating a time stamp as a current time stamp for a current packet by adding a specified offset time to said current time at which said current packet has appeared;
reading out a value of the time stamp for a previous packet having been stored as a value of a previous time stamp;
comparing a value of said current time stamp with said value of said previous time stamp;
updating said value of said previous time stamp having been stored with said value of said current time stamp and attaching said current time stamp to said current packet if said value of said current time stamp is more than said value of said previous time stamp;
discarding a predetermined packet if said value of said current time stamp is not more than said value of said previous time stamp;
storing said current packet attached with said current time stamp if said current packet is not discarded;
adjusting a timing of said current packet attached with said current time stamp so that said packet forms said packet string with substantially fixed packet intervals; and
transmitting said packet string with substantially fixed packet intervals.
1 Assignment
0 Petitions
Accused Products
Abstract
In transmitting a packet string having variable packet intervals by converting the packet string into that having even packet intervals with each of the packets being attached with a time stamp as information for reproducing original packet string, when the value of the time stamp, which is decided by adding a specified offset time to the synchronization time, is not smaller than the value of the time stamp attached to the previous packet, the time stamp is attached to the packet and the packet is transmitted. If the value of the time stamp becomes not more than the value of the time stamp attached to the previous packet as a result of providing shortened offset time due to increased bit rate of the original packet string, the packet is discarded so as to protect the transmission from being stopped.
166 Citations
16 Claims
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1. A method of transmitting a packet string with various packet intervals wherein an original packet string as said packet string with various packet intervals is transmitted from a transmitting side after being converted into a packet string with substantially fixed packet intervals comprising the steps of:
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calculating a time stamp as a current time stamp for a current packet by adding a specified offset time to said current time at which said current packet has appeared; reading out a value of the time stamp for a previous packet having been stored as a value of a previous time stamp; comparing a value of said current time stamp with said value of said previous time stamp; updating said value of said previous time stamp having been stored with said value of said current time stamp and attaching said current time stamp to said current packet if said value of said current time stamp is more than said value of said previous time stamp; discarding a predetermined packet if said value of said current time stamp is not more than said value of said previous time stamp; storing said current packet attached with said current time stamp if said current packet is not discarded; adjusting a timing of said current packet attached with said current time stamp so that said packet forms said packet string with substantially fixed packet intervals; and transmitting said packet string with substantially fixed packet intervals. - View Dependent Claims (2, 3, 4)
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5. A method of transmitting and receiving a packet string with various packet intervals wherein an original packet string as said packet string with various packet intervals is transmitted from a transmitting side after being converted into a packet string with substantially fixed packet intervals and is received at a receiving side comprising the steps of:
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calculating a time stamp as a current time stamp for a current packet by adding a specified offset time to said current time at which said current packet has appeared; reading out a value of the for a previous packet having been stored as a value of a previous time stamp; comparing a value of said current time stamp with said value of said previous time stamp; updating said value of said previous time stamp having been stored with said value of said current time stamp and attaching said current time stamp to said current packet if said value of said current time stamp is more than said value of said previous time stamp; discarding predetermined packet if said value of said current time stamp is not more than said value of said previous time stamp; storing said current packet attached with said current time stamp if said current packet is not discarded; adjusting a timing of said current packet attached with said current time stamp so that said packet forms said packet string with substantially fixed packet intervals; transmitting said packet string with substantially fixed packet intervals; receiving said packet string with substantially fixed packet intervals at said receiving side; storing said packet string with substantially fixed packet intervals having been received; and reading out stored said packet string with packet intervals according to said time stamps attached to said packets thereby reproducing said original packet string with variable packet intervals. - View Dependent Claims (6, 7, 8)
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9. An apparatus for transmitting a packet string with various packet intervals wherein an original packet string as said packet string with various packet intervals is transmitted from a transmitting side after being converted into a packet string with substantially fixed packet intervals comprising the steps of:
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means for calculating a time stamp as a current time stamp for a current packet by adding a specified offset time to said current time at which said current packet has appeared; means for reading out a value of the time stamp for a previous packet having been stored as a value of a previous time stamp; means for comparing a value of said current time stamp with said value of said previous time stamp; means for updating said value of said previous time stamp having been stored with said value of said current time stamp and attaching said current time stamp to said current packet if said value of said current time stamp is more than said value of said previous time stamp; means for discarding a predetermined packet if said value of said current time stamp is not more than said value of said previous time stamp; means for storing said current packet attached with said current time stamp if said current packet is not discarded; means for adjusting a timing of said current packet attached with said current time stamp so that said packet forms said packet string with substantially fixed packet intervals; and means for transmitting said packet string with substantially fixed packet intervals. - View Dependent Claims (10, 11, 12)
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13. A method of transmitting and receiving a packet string with various packet intervals wherein an original packet string as said packet string with various packet intervals is transmitted from a transmitting side after being converted into a packet string with substantially fixed packet intervals and is received at a receiving side comprising the steps of:
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means for calculating a time stamp as a current time stamp for said current packet by adding a specified offset time to said current time at which said current packet has appeared; means for reading out a value of a time stamp for a previous packet having been stored as a value of a previous time stamp; means for comparing a value of said current time stamp with said value of said previous time stamp; means for updating said value of said previous time stamp having been stored with said value of said current time stamp and attaching said current time stamp to said current packet if said value of said current time stamp is more than said value of said previous time stamp; means for discarding predetermined packet if said value of said current time stamp is not more than said value of said previous time stamp; means for storing said current packet attached with said current time stamp if said current packet is not discarded; means for adjusting a timing of said current packet attached with said current time stamp so that said packet forms said packet string with substantially fixed packet intervals; means for transmitting said packet string with substantially fixed packet intervals; means for receiving said packet string with substantially fixed packet intervals at said receiving side; means for storing said packet string with substantially fixed packet intervals having been received; and means for reading out stored said packet string with packet intervals according to said time stamps attached to said packets thereby reproducing said original packet string with variable packet intervals. - View Dependent Claims (14, 15, 16)
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Specification