APPARATUS AND METHOD FOR PROCESSING VOICE OVER INTERNET PROTOCOL PACKETS

• US 20090268714A1
• Filed: 04/25/2008
• Published: 10/29/2009
• Est. Priority Date: 04/25/2008
• Status: Active Grant

• Current Assignee: Chi Mei Communication Systems Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Chi Mei Communication Systems Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: HO, MIN-CHING
• Granted Patent: US 8,238,341 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04L 1/1841 Resequencing
• CPC Class Codes: H04L 65/1059 End-user terminal functionalities specially adapted for real-time communication
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04M 1/2535 adapted for voice communication over an Internet Protocol [IP] network Voice over Internet Protocol (VoIP) network equipment and services H04M7/006; implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP] H04L69/16

Abstract

A method for processing Voice over Internet Protocol (VoIP) packets is provided. The method includes: determining if the arrived VoIP packet arrives out of order according to a sequence number of the arrived VoIP packet and a sequence number of a preceding VoIP packet of the arrived VoIP packet; determining whether the buffer has a packet having a same sequence number as the arrived VoIP packet if the arrived VoIP packet arrives out of order; calculating the difference between the sequence number of the arrived VoIP packet and that of the preceding VoIP packet if the buffer has no such packet having the same sequence number as the arrived VoIP packet; and counting a number of pseudo packets needed to be inserted into the buffer according to the calculated difference and generating and inserting the number of pseudo packets into the buffer.

Claims

1. A method for processing Voice over Internet Protocol (VoIP) packets at an electronic apparatus, the method comprising the steps of:

(a) sending an VoIP packet to a buffer in the electronic apparatus;

(b) determining if the arrived VoIP packet arrives out of order according to a sequence number of the arrived VoIP packet and a sequence number of a preceding VoIP packet;

(c) determining whether the buffer has a packet having a same sequence number as the sequence number of the arrived VoIP packet, if the arrived VoIP packet arrives out of order;

(d) calculating the difference between the sequence number of the arrived VoIP packet and the sequence number of the preceding VoIP packet if the buffer has no such packet having the same sequence number as the arrived VoIP packet;

(e) counting a number of pseudo packets needed to be inserted into the buffer according to the calculated difference and generating the number of pseudo packets; and

(f) inserting the number of pseudo packets and the arrived VoIP packet into the buffer.

2. The method as claimed in claim 1, further comprising:

determining whether the buffer is empty after step (a); and

inserting the arrived VoIP packet into the buffer if the buffer is empty.

3. The method as claimed in claim 1, wherein each of the arrived VoIP packets comprises real time protocol information, including timestamp and a sequence number.

4. The method as claimed in claim 3, further comprising:

determining whether the arrived VoIP packet is late in accordance with the RTP information of the arrived VoIP packet and a dimension of the buffer after step (a).

5. The method as claimed in claim 4, further comprising:

dropping the arrived VoIP packet if the arrived VoIP packet is late; and

executing step (c) if the arrived VoIP packet is not late.

6. The method as claimed in claim 1, further comprising:

inserting the arrived VoIP packet into the buffer if the arrived VoIP packet arrives in a proper order after step (b).

7. The method as claimed in claim 1, further comprising:

determining whether the packet is a VoIP packet, if the buffer has the packet having the same sequence number as the sequence number of the arrived VoIP packet.

8. The method as claimed in claim 7, further comprising:

dropping the arrived VoIP packet if the packet is a VoIP packet; and

replacing the packet with the arrived VoIP packet if the packet is not a VoIP packet.

9. The method as claimed in claim 1, further comprising:

outputting packets in the buffer to an audio controlling module, wherein the output packets comprises the pseudo packets and the VoIP packets.

10. The method as claimed in claim 9, further comprising:

determining whether the output packets are the pseudo packets or the VoIP packets;

generating comfort noise if the output packets are the pseudo packets, and decompressing the output packets into raw data if the output packets are the VoIP packets; and

outputting the comfort noise and the raw data to an audio module for playing.

11. The method as claimed in claim 1, wherein the preceding packet is the VoIP packet previously inserted into the buffer before the arrived packet.

12. An apparatus for processing Voice over Internet Protocol (VoIP) packets at an electronic apparatus, the system comprising a real time transport protocol (RTP) module, a buffer, and an audio controlling module, wherein:

the RTP module is configured for receiving a plurality of arrived VoIP packets, and sending the arrived VoIP packets to the buffer one by one;

the buffer is configured for reordering the arrived VoIP packets by generating pseudo packets while the arrived VoIP arrives out of order, inserting the reordered VoIP packets and the generated pseudo packets into the buffer, and outputting packets in the buffer to the audio controlling module, the output packets comprising the pseudo packets and the VoIP packets; and

the audio controlling module configured for generating comfort noise if the output packets are the pseudo packets, decompressing the output packets into raw data if the output packets are the VoIP packets.

13. The apparatus as claimed in claim 12, wherein the buffer determines whether the arrived VoIP arrives out of order according to a sequence number of the arrived VoIP packet and a sequence number of a preceding VoIP packet.

14. The apparatus as claimed in claim 13, wherein the buffer reorders the arrived VoIP packets by generating pseudo packets via executing the functions of:

determining whether the buffer has a packet having a same sequence number as the sequence number of the arrived VoIP packet, if the arrived VoIP packet arrives out of order;

calculating the difference between the sequence number of the arrived VoIP packet and the sequence number of the preceding VoIP packet if the buffer has no such packet having the same sequence number as the arrived VoIP packet;

counting a number of pseudo packets needed to be inserted into the buffer according to the calculated difference and generating the number of pseudo packets; and

inserting the number of pseudo packets and the arrived VoIP packet into the buffer.

15. The apparatus as claimed in claim 14, wherein the buffer is further configured for:

determining whether the packet is a VoIP packet, if the buffer has the packet having the same sequence number as the sequence number of the arrived VoIP packet;

dropping the arrived VoIP packet if the packet is a VoIP packet; and

replacing the packet with the arrived VoIP packet if the packet is not a VoIP packet.

16. The apparatus as claimed in claim 12, wherein the buffer is further configured for determining whether the arrived VoIP packet is late in accordance with a RTP information of the arrived VoIP packet and a dimension of the buffer, dropping the arrived VoIP packet if the arrived VoIP packet is late.

17. The apparatus as claimed in claim 12, wherein the buffer is further configured for inserting the arrived VoIP packet into the buffer if the arrived VoIP packet arrives in a proper order.

18. The apparatus as claimed in claim 17, further comprising an audio module for playing the comfort noise and the raw data output from the audio control module.