<div>Ok thanks for your reply.</div>
<div>But can you please tell me is that must that chroma motion vectors are to be determined from luma motion vectors.</div>
<div>As far as my thinking For baseline profile (YUV 4:2:0) the chroma motion vectors are half to that of luma motion vectors. Am i correct? IF not how to get them?</div>
<div> </div>
<div>Best regards,</div>
<div>Mahesh.<br><br> </div>
<div><span class="gmail_quote">On 11/16/07, <b class="gmail_sendername">Panagiotis Issaris</b> <<a href="mailto:takis.issaris@uhasselt.be">takis.issaris@uhasselt.be</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">Hi Mahesh,<br><br>mahesh k schreef:<br>> Hi all,<br>><br>> Can any one please tell me whats the need of having different horizontal and
<br>> vertical ranges for motion vector components in H.264 . Also the horizontal<br>> ranges are independent of levels but the vertical ranges depend on level of<br>> the decoder ?<br>><br>> I am working on
H.264 decoder (Constrained to only baseline profile).<br>> Please tell me how to handle the motion vectors if they point to a<br>> Macroblock outside the frame boundary.?<br><br>AFAIK, if they point left or right of the frame boundary, you have to
<br>replicate the pixels on the border, so, if this would be a block at the<br>extreme right of the frame, right at the border:<br>45 34 37 40 |<br>34 33 45 46 |<br>12 13 34 35 |<br>43 44 46 59 |<br><br>This would become something like this:
<br>45 34 37 40 | 40 40 40 ...<br>34 33 45 46 | 46 46 46 ...<br>12 13 34 35 | 35 35 35 ...<br>43 44 46 59 | 59 59 59 ...<br><br>Similar for a motion vector pointing above or below the frame boundary.<br><br>I'm pretty sure about this for luma, less sure for chroma...
<br><br>And, unfortunately, I'm not sure yet what happens for motion vectors<br>pointing outside the corners of the frame.<br><br><br>And just as it might help you in the future: There's two mailinglist<br>which are not about a specific
H.264 encoder but are more about<br>MPEG-4/H.264 in general: mp4-tech[1] and jvt-experts[2].<br><br>With friendly regards,<br>Takis<br>--<br>vCard: <a href="http://issaris.org/pi.vcf">http://issaris.org/pi.vcf</a><br>PGP key:
<a href="http://issaris.org/pi.key">http://issaris.org/pi.key</a><br><br><br><br>[1] <a href="http://lists.mpegif.org/mailman/listinfo/mp4-tech">http://lists.mpegif.org/mailman/listinfo/mp4-tech</a><br>[2] <a href="http://mailman.rwth-aachen.de/mailman/listinfo/jvt-experts">
http://mailman.rwth-aachen.de/mailman/listinfo/jvt-experts</a><br>_______________________________________________<br>x264-devel mailing list<br><a href="mailto:x264-devel@videolan.org">x264-devel@videolan.org</a><br><a href="http://mailman.videolan.org/listinfo/x264-devel">
http://mailman.videolan.org/listinfo/x264-devel</a><br></blockquote></div><br>