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<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>Since there seems to be quite a few
ppl writing H.264 frame subclasses, I think i'll give a gist of what I learned
when i was creating one;<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>Basically, my stream was 0x00 00 00
01 delimited single NAL unit entities - the first NAL was my SPS, then PPS and
then picture slices after that.<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>In your framer, after the delimiter,
you read 1 byte, which is contains basic info about the NAL unit - once you
have this byte, you parse it:<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>NAL_nri = (readChar >> 5)
& 0x3;<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>NAL_type = readChar & 0x1F;<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>NAL_forbidden = readChar & 0x80;
<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>Now, if your NAL unit size is less
than ethernet MTU (~1400 bytes), then you can go ahead and do single-NAL unit
mode in which case you drop the 4 byte delimiter, and pass this to liveMedia to
send<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>If it is > 1400 byte (most of the
time they are), then you'll have to do FU-A mode; FU-A mode specially requires
an indicator and a header.<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>FU_indicator = (NAL_forbidden
<< 7) | (NAL_nri << 5) | (28); //28 is FU-A type<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>FU_header = (NAL_type) |
(FUA_START); //FUA_START is 1<<7<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>This indicator goes first, then the
header, and then you append your NAL unit data - NOTE however, that the NAL
unit data you append should not have the delimiter AND the 1 byte NAL info
present.<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>After this first transmission, you
send successive FU-A packets with the remaining NAL unit data with the same
FU_indicator, but a changed FU_header<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>if the current packet you're sending
is not the last packet, then:<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>FU_header = (NAL_type); //dont
signal the end yet, as per RFC Spec <o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>if it is the last packet then:<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>FU_header = (NAL_type) | (FUA_END);
//signal last frame of NAL unit, FUA_END = 1<<6<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>That's as easy as it gets to sending
H.264 data to VLC and it should play it beautifully :)<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><strong><b><font size=2 face=Arial><span style='font-size:
10.0pt;font-family:Arial'>Jerry Johns</span></font></b></strong><o:p></o:p></p>
<p class=MsoNormal><em><i><font size=1 face=Arial><span style='font-size:7.5pt;
font-family:Arial'>Design Engineer</span></font></i></em><o:p></o:p></p>
<p class=MsoNormal><em><i><font size=1 color=blue face=Arial><span
style='font-size:7.5pt;font-family:Arial;color:blue'>Nuvation Research Corp - <st1:country-region
w:st="on"><st1:place w:st="on">Canada</st1:place></st1:country-region></span></font></i></em><o:p></o:p></p>
<p class=MsoNormal><em><i><font size=1 color=blue face=Arial><span
style='font-size:7.5pt;font-family:Arial;color:blue'>Tel: (519) 746-2304 ext.
225</span></font></i></em><o:p></o:p></p>
<p class=MsoNormal><em><i><font size=1 color=blue face=Arial><span
style='font-size:7.5pt;font-family:Arial;color:blue'><a
href="http://www.nuvation.com"><font face="Times New Roman"><span
style='font-family:"Times New Roman"'>www.nuvation.com</span></font></a></span></font></i></em><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span><o:p></o:p></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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