<html dir="ltr">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta content="MSHTML 6.00.2900.3627" name="GENERATOR">
<style title="owaParaStyle"><!--P {
MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px
}
--></style>
</head>
<body ocsi="x">
<div dir="ltr"><font face="Tahoma" color="#000000" size="2">Hi Ross,</font></div>
<div dir="ltr"><font face="tahoma" size="2"></font> </div>
<div dir="ltr"><font face="tahoma" size="2">I have some doubts regarding the RTP Payload for MP3.</font></div>
<div dir="ltr"><font face="tahoma" size="2"></font> </div>
<div dir="ltr"><font face="tahoma" size="2">1) When I received the payload it's something like this </font></div>
<div dir="ltr"><font face="tahoma" size="2"><font face="tahoma"> </font> 00 00 00 00 ff e3 e8 .....</font></div>
<div dir="ltr"><font face="tahoma" size="2"> The valid data starts only after 4 bytes in all the cases. Why is that so?</font></div>
<div dir="ltr"><font face="tahoma" size="2"></font> </div>
<div dir="ltr"><font face="tahoma" size="2">2) I tried streamed a clip with the following configuration</font></div>
<div dir="ltr"><font face="tahoma" size="2"> <strong> MPEG 2.5 Layer III</strong></font></div>
<div dir="ltr"><font face="tahoma" size="2"><strong><font face="tahoma"> 160kbps , strereo, </font><font face="Times New Roman" size="3"> </font></strong></font></div>
<div dir="ltr"><font face="times new roman"><strong> Sampling Rate: 8000 hz</strong></font> </div>
<div dir="ltr"><font face="times new roman"> </font></div>
<div dir="ltr"><font face="times new roman"> In this case, the size of the Computed frame is 1440. So single frame comes in 2 RTP packets.
</font></div>
<div dir="ltr"><font face="times new roman"> The payload length in the first packet is 1436. The payload looked like this
</font></div>
<div dir="ltr"><font face="times new roman"> 00 00 00 00 ff e3 e8 ....</font></div>
<div dir="ltr"><font face="times new roman"> </font></div>
<div dir="ltr"><font face="times new roman"> In the second RTP packet, the payload length was 12. And the 12 bytes looks like this
</font></div>
<div dir="ltr"><font face="times new roman"> 00 00 05 98 00 00 00 00 00 00 00 00.</font></div>
<div dir="ltr"><font face="times new roman"></font> </div>
<div dir="ltr"><font face="times new roman"> Now I have to give 1440 bytes to my decoder. From the first packet the valid data starts after 4 bytes,</font></div>
<div dir="ltr"><font face="times new roman"> So the valid data would be of size
</font><font face="times new roman">1432 bytes. From the Second packet which 8 bytes should I give the</font></div>
<div dir="ltr"><font face="times new roman"> decoder?. First 8 bytes or last 8 bytes.
</font></div>
<div dir="ltr"><font face="times new roman"> </font></div>
<div dir="ltr"><font face="times new roman"> </font><font face="times new roman">
</font></div>
<div dir="ltr"><font face="times new roman"> I have attached the ethreal logs also.
</font> Kindly look into them and give your suggestions.</div>
<div dir="ltr"><font face="times new roman"> Also let me know the general rule in handling the continuation frames, coming in multiple RTP Packets.</font></div>
<div dir="ltr"><font face="tahoma" size="2"></font><font face="tahoma" size="2"></font> </div>
<div dir="ltr"><font face="tahoma" size="2"></font> </div>
<div dir="ltr"><font face="tahoma" size="2"></font> </div>
<div class="BodyFragment"><font size="2">
<div class="PlainText">Regards<br>
Sathish Kumar M<br>
</div>
</font></div>
<br>
<hr>
<font face="Arial" color="Gray" size="3">"DISCLAIMER: This message is proprietary to Aricent and is intended solely for the use of the individual to whom it is addressed. It may contain privileged or confidential information and should not be circulated or
used for any purpose other than for what it is intended. If you have received this message in error,please notify the originator immediately. If you are not the intended recipient, you are notified that you are strictly prohibited from using, copying, altering,
or disclosing the contents of this message. Aricent accepts no responsibility for loss or damage arising from the use of the information transmitted by this email including damage from virus."<br>
</font>
</body>
</html>