This means that high dynamic range video (HDR) is currently considered non-standard, and will be normalized to SDR. If you don't know what this is, you can probably ignore this, since most streaming video is 8-bit 4:2:0. This refers to the color depth and chroma subsampling. While Mux accepts higher bitrate inputs, bitrates higher than 8Mbps (and the bitrate should not exceed 16Mbps for any single GOP) are generally challenging for most viewer's connections and are considered non-standard.

Standard input must be closed-GOP, which means that open-GOP video will be treated as non-standard and will be normalized to standard. This means that every GOP can be played independently, without reference to another GOP. Closed GOP always begins with an IDR (Instantaneous Decoder Refresh) frame. You can likely ignore this.) In closed-GOP video, all B frames reference other frames in the same GOP. To stream well using HTTP-based streaming methods like HLS, Mux requires all keyframes intervals to be less than 20 seconds. While Mux accepts other CODECs as input, other CODECs must be normalized to H.264 and are considered non-standard. H.264 is the dominant video CODEC in use today and almost every device supports H.264. Video larger than this is considered non-standard. Video up to 2048x2048 is considered standard, including 1080p (1920x1080) video. Standard input has the following attributes.

Ffmpeg resize video 1080p