<story><title>HDMI 2.0 officially announced</title><url>http://www.engadget.com/2013/09/04/hdmi-2-0-official-4k-60fps-32-channel-audio/</url></story><parent_chain><item><author>rootbear</author><text>This race for more pixels is misguided.  The change I most want to see is deeper pixels, at least 10bpp, preferably more.  I&amp;#x27;m getting really tired of all the banding I see on what should be smooth gradient images. If a landscape aspect image is P pixels wide then to display a gray scale gradient, black to white, you need&lt;p&gt;ceil(log2(P))&lt;p&gt;bits per pixel.  So a &amp;quot;2K&amp;quot; display needs 11 bits, &amp;quot;4K&amp;quot; needs 12, etc.  Then each column of pixels gets a distinct value and there is no banding.&lt;p&gt;So sure, give me a 4K screen. I&amp;#x27;ve seen them and they are sweet, but you MUST also increase the pixel depth at the same time, or there will be artifacts.&lt;p&gt;And don&amp;#x27;t get me started on the horrid compression artifacts on basic cable.  A crime against quality imagery.</text></item></parent_chain><comment><author>Daiz</author><text>Dithering can help a lot when it comes to displaying large smooth gradients in lower bit depths. Obviously it has its downsides, though - for one, you need to actually implement it where smooth gradients are used, and at when it comes to video games this basically never happens and you end up with notable banding instead.&lt;p&gt;Dithering in the field of video is pretty common, though. But it has a pretty large problem there as well - since dithering is essentially noise, it requires a lot of bitrate to compress efficiently, and if you don&amp;#x27;t have bitrate to throw at your source, you&amp;#x27;re most likely going to kill it and just end up introducing banding. Blu-ray is pretty much the main avenue where you have enough bitrate to spare for proper dithering in 8-bit video. Anything less than that, though... well, let&amp;#x27;s just say that House of Cards on Netflix was suffering from banding a lot.&lt;p&gt;Banding is actually one of the biggest reasons why anime fansubs these days are generally encoded in 10-bit H.264. Anime tends to have a lot of large and smooth color surfaces and banding was pretty much the hardest thing to avoid with regular 8-bit video - 10-bit on the other hands makes it an almost total non-issue. And for non-10bit displays, it moves the necessary dithering to the playback end, which is obviously a much nicer alternative since you don&amp;#x27;t have to compress any of that in the video itself. And beyond the gradients, 10-bit H.264 actually gives you better compression quality in general, which just makes it even better.&lt;p&gt;Now, it obviously comes with the downside of not being supported by hardware decoders anywhere, so you basically will need a decent CPU to decode 10-bit video. For fansubs and the people who make them this isn&amp;#x27;t that much of an issue though, since the advanced subtitles they use are also generally poorly-supported by hardware players, and this has been the case for a long time.&lt;p&gt;Next-generation video formats may actually bring higher bit depths to hardware decoders as well, though - H.265&amp;#x2F;HEVC has a Main 10 Profile intended for consumer applications.</text></comment>
<story><title>HDMI 2.0 officially announced</title><url>http://www.engadget.com/2013/09/04/hdmi-2-0-official-4k-60fps-32-channel-audio/</url></story><parent_chain><item><author>rootbear</author><text>This race for more pixels is misguided.  The change I most want to see is deeper pixels, at least 10bpp, preferably more.  I&amp;#x27;m getting really tired of all the banding I see on what should be smooth gradient images. If a landscape aspect image is P pixels wide then to display a gray scale gradient, black to white, you need&lt;p&gt;ceil(log2(P))&lt;p&gt;bits per pixel.  So a &amp;quot;2K&amp;quot; display needs 11 bits, &amp;quot;4K&amp;quot; needs 12, etc.  Then each column of pixels gets a distinct value and there is no banding.&lt;p&gt;So sure, give me a 4K screen. I&amp;#x27;ve seen them and they are sweet, but you MUST also increase the pixel depth at the same time, or there will be artifacts.&lt;p&gt;And don&amp;#x27;t get me started on the horrid compression artifacts on basic cable.  A crime against quality imagery.</text></item></parent_chain><comment><author>mgraczyk</author><text>The banding you see is from image and video compression, not a lack of bpp.  Human beings can almost never differentiate 6 bpp from 8 bpp grayscale, and with colors 7 bpp&amp;#x2F;c is almost always sufficient.</text></comment>