AFAIK There is no way you can decrease bitrate for initial I-frame since there is no frames before that frame to serve for prediction.<br>The only way at that point is to use higher QP or to use different encoding standard.<br> <br>cyclic intra macroblock refresh can help you to remove bitrate fluctuation on I-frames but still first frame has to be intra predicted (has to be I).<br><br><br><div class="gmail_quote">2011/12/4 Umakant Goyal <span dir="ltr"><<a href="mailto:umakantgoyal1@gmail.com">umakantgoyal1@gmail.com</a>></span><br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Thanks Michael, My Problem is that initial I-Frame size (bitrate) is very high. I want to reduce the size of initial I-Frame.<br> <br>How can i force encoder to do cyclic intra macroblock refresh instead of periodical intra-frame refresh? <br><div><div></div><div class="h5"> <br><div class="gmail_quote">On Sun, Dec 4, 2011 at 2:42 PM, Michael Joachimiak <span dir="ltr"><<a href="mailto:mjoachimiak@gmail.com" target="_blank">mjoachimiak@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Bitrate fluctuation is normal in case of I-frame. I don't know if you can do much about it apart from using rate control. <div>Do you use any rate control?</div><div>Instead of having periodical intra-frame refresh you could have cyclic intra macroblock refresh. It means you do not refresh the whole frame at once but you have some macroblocks forced to be encoded as intra in every frame.</div> <div>Thus the whole frame is intra-refreshed after some period of time.<div><div></div><div><br><br><div class="gmail_quote">2011/12/3 Umakant Goyal <span dir="ltr"><<a href="mailto:umakantgoyal1@gmail.com" target="_blank">umakantgoyal1@gmail.com</a>></span><br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi Ashwini, I think you misunderstood me. Here i am not talking about picture size.I need to reduce the number of bits that is being produced by encoder to generate I-Frame. Please suggest how to reduce the number of bits for per I-Frame without loosing the quality much.<br> <br>Thanks<div><div></div><div><br><br><div class="gmail_quote">On Fri, Dec 2, 2011 at 4:43 PM, Ashwini Sharma <span dir="ltr"><<a href="mailto:ak.ashwini@gmail.com" target="_blank">ak.ashwini@gmail.com</a>></span> wrote:<br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Hi,<div><br></div><div>I think you can use videoscale to do the job.</div><div><br></div><div>--Ashwini<br><br><div class="gmail_quote"><div>On Mon, Nov 28, 2011 at 10:58 PM, Umakant Goyal <span dir="ltr"><<a href="mailto:umakantgoyal1@gmail.com" target="_blank">umakantgoyal1@gmail.com</a>></span> wrote:<br> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>Hi, What all settings of ffenc_h263 will help me to control/reduce the size of I-Frame?<br><br>Thanks in Advance <br> <br></div>_______________________________________________<br> gstreamer-devel mailing list<br> <a href="mailto:gstreamer-devel@lists.freedesktop.org" target="_blank">gstreamer-devel@lists.freedesktop.org</a><br> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><br> <br></blockquote></div><br></div> <br>_______________________________________________<br> gstreamer-devel mailing list<br> <a href="mailto:gstreamer-devel@lists.freedesktop.org" target="_blank">gstreamer-devel@lists.freedesktop.org</a><br> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><br> <br></blockquote></div><br> </div></div><br>_______________________________________________<br> gstreamer-devel mailing list<br> <a href="mailto:gstreamer-devel@lists.freedesktop.org" target="_blank">gstreamer-devel@lists.freedesktop.org</a><br> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><br> <br></blockquote></div><br><br clear="all"><div><br></div></div></div><font color="#888888">-- <br>Your Sincerely<br>Michal Joachimiak<br> </font></div> <br>_______________________________________________<br> gstreamer-devel mailing list<br> <a href="mailto:gstreamer-devel@lists.freedesktop.org" target="_blank">gstreamer-devel@lists.freedesktop.org</a><br> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><br> <br></blockquote></div><br> </div></div><br>_______________________________________________<br> gstreamer-devel mailing list<br> <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a><br> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><br> <br></blockquote></div><br><br clear="all"><br>-- <br>Your Sincerely<br>Michal Joachimiak<br>