{"id":3456,"date":"2013-06-20T14:16:05","date_gmt":"2013-06-20T11:16:05","guid":{"rendered":"http:\/\/mummila.net\/nuudelisoppa\/?p=3456"},"modified":"2013-06-20T14:16:05","modified_gmt":"2013-06-20T11:16:05","slug":"transcoding-note-targeting-quality-with-vp8","status":"publish","type":"post","link":"https:\/\/mummila.net\/nuudelisoppa\/2013\/06\/20\/transcoding-note-targeting-quality-with-vp8\/","title":{"rendered":"Transcoding note: targeting quality with VP8"},"content":{"rendered":"<p>In CQ mode, <code>--target-bitrate<\/code> becomes \u201ctarget maximum rate\u201d. If requested quality (<code>--cq-level<\/code>) can be achieved with less (than <code>--target-bitrate<\/code>) bits, it will be encoded so, but <code>--target-bitrate<\/code> does set the hard <em>upper<\/em> limit for bitrate. In addition, it defaults quite low if unset, even in CQ mode; at least my intuition (stemming from experience with Vorbis, probably) assumes CQ mode without set bitrate would take all the bits it needs to achieve the requested quality, but not so.<\/p>\n<p>So, if reaching a certain size doesn&#8217;t matter, but quality does, I suggest <code>--end-usage=cq<\/code> and overshooting <code>--target-bitrate<\/code> with a high enough number to guarantee that quality is limited by CQ controls (<code>--cq-level<\/code>, <code>--min-q<\/code> and <code>--max-q<\/code>) alone, not by bitrate. Remember, any crazy big bitrate value will still be undershot if all of those bits aren&#8217;t actually needed to hit the quality target.<\/p>\n<p>The default <code>--cq-level<\/code> value of 10 seems quite well struck (for certain material I can&#8217;t tell the difference from level 5 despite the +30% increase in file size), but even level 20 still doesn&#8217;t seem too bad (again, for the material I&#8217;ve tested it with, resulting in additional 30% saved in file size).<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In CQ mode, &#8211;target-bitrate becomes \u201ctarget maximum rate\u201d. If requested quality (&#8211;cq-level) can be achieved with less (than &#8211;target-bitrate) bits, it will be encoded so, but &#8211;target-bitrate does set the hard upper limit for bitrate. In addition, it defaults quite low if unset, even in CQ mode; at least my intuition (stemming from experience with [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3456","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/posts\/3456","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/comments?post=3456"}],"version-history":[{"count":4,"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/posts\/3456\/revisions"}],"predecessor-version":[{"id":3460,"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/posts\/3456\/revisions\/3460"}],"wp:attachment":[{"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/media?parent=3456"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/categories?post=3456"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mummila.net\/nuudelisoppa\/wp-json\/wp\/v2\/tags?post=3456"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}