HTC One M9 video recording samples: 4K and 1080p demonstration
The HTC One M9 does away with the 4-megapixel 'UltraPixel' rear camera that it has used in the past two generations and make the jump all the way up to a 20-megapixel main shooter (don't worry, though, UltraPixel technology lives on in the front, selfie camera of the phone).
This gives HTC the possibility to offer 4K video recording along with the traditionally offered 1080p.
The One M9 records 4K UHD video at up to 30 frames per second and we got a chance to test this new feature at MWC 2015. While most monitors and TV sets do not yet support the 4K resolution, there are benefits to watching 4K videos on even a 1080p display such as chroma sub-sampling in 1080p.
Put simply, chroma sub-sampling is a common practice in most smartphones and cameras alike that encode video files using less resolution for chroma (aka color, as opposed to luma aka light). The default 4:2:0 chrome subsampling is lossy in terms of color, but when you watch 4K videos downsized to 1080p chroma subsampling gets translated to a lossless format, which means richer color reproduction.
Interestingly, we've heard promises of Snapdragon 810 supporting the new H.265 encoding for more efficient compression with less artifacts, but both the Galaxy S6 and One M9 do not use that feature and video recordings still appear in the good ol' H.264 encoding format.
We've also got a 1080p video sample shot on the One M9 that could be used when you want to record longer videos and don't have a lot of free storage left for instance. Take a look at the two samples (don't forget that YouTube compresses the files additionally), and let us know your thoughts about the video recording capabilities of the M9.