Keep precision separate from sample layout
An 8-bit component can represent 256 code values; a 10-bit component can represent 1,024. These counts describe numeric precision, not the number of physical pixels on the television. Chroma sampling describes a different relationship between luma and colour-difference samples. A description such as 10-bit 4:2:0 therefore contains two independent properties. Retain both when reading a file report or a decoder specification.
Read the chroma notation in context
The familiar 4:2:0, 4:2:2 and 4:4:4 labels describe different chroma sample arrangements. They do not mean that a 4:4:4 picture has four times the overall screen resolution. A codec specification can permit some combinations and restrict others. AV1’s profile table is one concrete example: permitted bit depths and chroma formats depend on the selected profile, rather than being implied by the word AV1.
Do not infer HDR from 10-bit alone
A precision value is not the complete colour interpretation. The transfer characteristics, colour primaries and other signalling remain relevant to what the picture means. A television’s HDR indicator is also not a comprehensive inspection of every encoding property. If a gradient looks banded, avoid immediately blaming the nominal bit depth; processing, source quality and display behaviour may all warrant investigation before changing output settings.
Apply this to a real purchase or fault
For compatibility, ask about the precise codec/profile and bit-depth/chroma combination needed by the intended material. For desktop text over HDMI, investigate the display connection separately from a compressed video file. Do not transfer a decoder’s supported input sampling directly into a claim about the television’s output mode. An authorised representative sample gives a more useful result than choosing the largest-looking number in every menu.
Questions, answered
Does 10-bit automatically mean HDR?
No. Bit depth specifies numerical precision. The transfer function and colour signalling are separate properties that must also be interpreted correctly by the playback chain.