<DIV>Hello everyone,</DIV>
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<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">In live555 library, in the file RTPSink.cpp, and in the function convertToRTPTimestamp:<o:p></o:p></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"><o:p> </o:p></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">RTPSink::convertToRTPTimestamp(struct timeval tv) {<BR>// Begin by converting from "struct timeval" units to RTP timestamp units:<BR></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">(1)u_int32_t timestampIncrement = (fTimestampFrequency*tv.tv_sec);<BR></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"><FONT color="#f000f0">(2)</FONT>timestampIncrement += (u_int32_t)((2.0*fTimestampFrequency*tv.tv_usec + 10000000)/2000000);</SPAN><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"></SPAN></P></DIV>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><BR>// note: rounding<o:p></o:p></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"><o:p> </o:p></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">I found the (2) statement is some strange. In fact, it is equal to </SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"></SPAN> </P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">90000*(tv.tv_usec) + 0.5</SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"></SPAN> </P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"> Can anyone tell me why it compute the timestamp this way? Why there is a 0.5?</SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"><o:p> </o:p></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">Thank in advance.<o:p></o:p></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"><o:p> </o:p></SPAN></P>
<P class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: left; mso-pagination: widow-orphan" align="left"><st1:City><st1:place><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体">Austin</SPAN></st1:place></st1:City><SPAN lang="EN-US" style="FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-font-kerning: 0pt; mso-bidi-font-family: 宋体"><o:p></o:p></SPAN></P>
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