 
 <prompt> Wetin be di apect ratio of a full screen tv? Based on di question wey dey before dis one, write small tori wey get di answer. E fit be 1 - 20 sentences. Context: <response>: In November 2008, 720p HD support waka enta. At di time wey dem launch 720p, di YouTube player change from 4:3 aspect ratio to widescreen 16:9. Wit dis new tori, YouTube start to dey use H.264/MPEG-4 AVC as dia default video compression format. In November 2009, 1080p HD support waka enta. For July 2010, YouTube announce say dem don launch videos for 4K format, wey allow resolution of up to 4096×3072 pixels. For June 2015, support for 8K resolution waka enta, wit di videos dey play for 7680×4320 pixels. 