<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Hi,<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I want to encode videos with constant QP and maximum frame size. I don't care about average bitrate. CRF does not meet the target QP I requested.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I tried to use –qp with –vbv-bufsize and –vbv-maxrate, but I get a warning "VBV is incompatible with constant QP, ignored."<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>I came across xsplit documation who claims to do with x264 exactly what I want to do:<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>"XSplit uses quality based encoding and sets a VBV-maxrate and VBV-buffer. This basically means that the x264 encoder in XSplit tries to maintain a constant quality of the stream and can use less bandwidth in less complex or less important scenes. The VBV-maxrate puts a ceiling to the bandwidth that encoder can use, but relative to the VBV-buffer. "<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><span class=apple-converted-space><span style='font-size:10.5pt;font-family:"Arial","sans-serif";color:white;background:#1A1A1A'><o:p> </o:p></span></span></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>What are the proper parameter to achieve constant QP with VBV?<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Thanks.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'>Tsahi.<o:p></o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p><p class=MsoNormal style='text-align:left;direction:ltr;unicode-bidi:embed'><o:p> </o:p></p></div></body></html>