Windows Media Format SDK - Too much of latency

[Sam]

Please reply...

Hello,
I am using WMF SDK to create a video stream out of many BMPs(Live source). I
am getting around 3-4 seconds of delay.
I am passing uncompressed packets using IWMWriter::WriteSample(...) method.
Is there any way to reduce the delay?
Following is my writer profile. After configuring following profile, I am
setting the buffer window (using
SetBufferWindow) to 200 ms. Still the delay is around 3-4 seconds.
<profile version="589824"
storageformat="1"
name="test"
description="Streams: 1 video">
<streamconfig majortype="{73646976-0000-0010-8000-00AA00389B71}"
streamnumber="1"
streamname="Video Stream"
inputname="Video409"
bitrate="239000"
bufferwindow="1000"
reliabletransport="0"
decodercomplexity="SP"
rfc1766langid="en-us"
<videomediaprops maxkeyframespacing="20000000"
quality="60"/>
<wmmediatype subtype="{33564D57-0000-0010-8000-00AA00389B71}"
bfixedsizesamples="0"
btemporalcompression="1"
lsamplesize="0">
<videoinfoheader dwbitrate="239000"
dwbiterrorrate="0"
avgtimeperframe="333667">
<rcsource left="0"
top="0"
right="320"
bottom="240"/>
<rctarget left="0"
top="0"
right="320"
bottom="240"/>
<bitmapinfoheader biwidth="320"
biheight="240"
biplanes="1"
bibitcount="24"
bicompression="WMV3"
bisizeimage="0"
bixpelspermeter="0"
biypelspermeter="0"
biclrused="0"
biclrimportant="0"/>
</videoinfoheader>
</wmmediatype>
</streamconfig>
</profile>
�
Thanks in advance.
Regards,
Samir

[Jeremy Noring]

Post by Sam
Please reply...

Hello,
I am using WMF SDK to create a video stream out of many BMPs(Live source). I
am getting around 3-4 seconds of delay.
I am passing uncompressed packets using IWMWriter::WriteSample(...) method.
Is there any way to reduce the delay?

Yes: use something other than the WMFSDK. If you'd have taken thirty
seconds to search the forum, you would have quickly found that the
WMFSDK is unsuitable for low-latency applications. The only way I've
been able to get low-latency out of the library is to use the DMO
filters directly, and then use my own video streaming code.

[Sam]

Post by Jeremy Noring

Post by Sam
Please reply...

Hello,
I am using WMF SDK to create a video stream out of many BMPs(Live source). I
am getting around 3-4 seconds of delay.
I am passing uncompressed packets using IWMWriter::WriteSample(...) method.
Is there any way to reduce the delay?

Yes: use something other than the WMFSDK. If you'd have taken thirty
seconds to search the forum, you would have quickly found that the
WMFSDK is unsuitable for low-latency applications. The only way I've
been able to get low-latency out of the library is to use the DMO
filters directly, and then use my own video streaming code.
.

Thank you Jeremy Noring for your answer.

So since windows media service will take input from encoder, we cannot
achieve realtime video (close to zero latency). Is that correct?

Do you think if I skip the encoding by streaming compressed data thru asf
compressed stream?

Thanks in advance