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</o:shapelayout></xml><![endif]--></head><body lang=JA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>lambda for RDO is proportional to pow(2.0, qp / 3.0).<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'>so, the qp offset here also needs to be devided by 3.0.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Arial","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0mm 0mm 0mm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0mm 0mm 0mm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> x265-devel [mailto:x265-devel-bounces@videolan.org] <b>On Behalf Of </b>Deepthi Nandakumar<br><b>Sent:</b> Tuesday, March 25, 2014 7:55 PM<br><b>To:</b> Development for x265<br><b>Subject:</b> Re: [x265] fix chroma lambda weighting<o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><div><p class=MsoNormal><span lang=EN-US>Thanks, very interesting fix. Can you give us some background here? Where did we the divide by 3.0 come from?<o:p></o:p></span></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><span lang=EN-US><o:p> </o:p></span></p><div><p class=MsoNormal><span lang=EN-US>On Tue, Mar 25, 2014 at 9:01 AM, Satoshi Nakagawa <<a href="mailto:nakagawa424@oki.com" target="_blank">nakagawa424@oki.com</a>> wrote:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US># HG changeset patch<br># User Satoshi Nakagawa <<a href="mailto:nakagawa424@oki.com">nakagawa424@oki.com</a>><br># Date 1395672158 -32400<br># Mon Mar 24 23:42:38 2014 +0900<br># Node ID 08584b5913bce6a5f9d2f0d408fcdace6aa83a65<br># Parent fdd7c6168cf42a11240ff1c7fc7b401605524db2<br>fix chroma lambda weighting<br><br>diff -r fdd7c6168cf4 -r 08584b5913bc source/encoder/frameencoder.cpp<br>--- a/source/encoder/frameencoder.cpp Fri Mar 21 14:44:35 2014 -0500<br>+++ b/source/encoder/frameencoder.cpp Mon Mar 24 23:42:38 2014 +0900<br>@@ -335,11 +335,10 @@<br> // instead we weight the distortion of chroma.<br> int chromaQPOffset = slice->getPPS()->getChromaCbQpOffset() + slice->getSliceQpDeltaCb();<br> int qpc = Clip3(0, MAX_MAX_QP, qp + chromaQPOffset);<br>- double cbWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc])); // takes into account of the chroma qp mapping and chroma qp Offset<br>-<br>+ double cbWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc]) / 3.0); // takes into account of the chroma qp mapping and chroma qp Offset<br> chromaQPOffset = slice->getPPS()->getChromaCrQpOffset() + slice->getSliceQpDeltaCr();<br> qpc = Clip3(0, MAX_MAX_QP, qp + chromaQPOffset);<br>- double crWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc])); // takes into account of the chroma qp mapping and chroma qp Offset<br>+ double crWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc]) / 3.0); // takes into account of the chroma qp mapping and chroma qp Offset<br> double chromaLambda = lambda / crWeight;<br><br> m_rows[row].m_search.setQPLambda(qp, lambda, chromaLambda);<br>@@ -376,10 +375,10 @@<br> int qpc;<br> int chromaQPOffset = slice->getPPS()->getChromaCbQpOffset() + slice->getSliceQpDeltaCb();<br> qpc = Clip3(0, MAX_MAX_QP, qp + chromaQPOffset);<br>- double cbWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc])); // takes into account of the chroma qp mapping and chroma qp Offset<br>+ double cbWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc]) / 3.0); // takes into account of the chroma qp mapping and chroma qp Offset<br> chromaQPOffset = slice->getPPS()->getChromaCrQpOffset() + slice->getSliceQpDeltaCr();<br> qpc = Clip3(0, MAX_MAX_QP, qp + chromaQPOffset);<br>- double crWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc])); // takes into account of the chroma qp mapping and chroma qp Offset<br>+ double crWeight = pow(2.0, (qp - g_chromaScale[chFmt][qpc]) / 3.0); // takes into account of the chroma qp mapping and chroma qp Offset<br> double chromaLambda = lambda / crWeight;<br><br> // NOTE: set SAO lambda every Frame<br>_______________________________________________<br>x265-devel mailing list<br><a href="mailto:x265-devel@videolan.org">x265-devel@videolan.org</a><br><a href="https://mailman.videolan.org/listinfo/x265-devel" target="_blank">https://mailman.videolan.org/listinfo/x265-devel</a><o:p></o:p></span></p></div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></div></body></html>