4:4:4 chroma subsampling test
24A short and simple test to see if YouTube supports 4:4:4 (yuv444p) chroma subsampling.
It's actually not even supported by most video players, which is pretty disheartening, because that means you can never see lossless video.
The result: YouTube doesn't even recognise yuv444p video. It attempts to reconvert it, and the result is not only the loss in colour information, but also the loss in general quality. The text is much less readable than the original upload, and the colours are incorrect.
You can see the original image used here: http://ffmpeg.org/pipermail/ffmpeg-user/attachments/20140104/bc520c23/attachment.png
Also note that the effect is even greater when the text is on a non-solid-colour background, because the background colours get blurred onto the text.