When the video type is flv as reported by the thumb info API, e.g. http://ext.nicovideo.jp/api/getthumbinfo/sm1715919, the HTML5 player will always be served the low quality mp4 source. swf movies are unaffected as the HTML5 player always redirects to the Flash player.
When the video type is
flv
as reported by the thumb info API, e.g. http://ext.nicovideo.jp/api/getthumbinfo/sm1715919, the HTML5 player will always be served the low qualitymp4
source.swf
movies are unaffected as the HTML5 player always redirects to the Flash player.