False error "BackgroundColor #000000c2, #00000033 is not transparent"

[Murmur]

See this ttml.xml file and errors given by the validator.
https://refapp.hbbtv.org/videos/00_llama_h264_v9/sub_fin_v4.xml

See errors BackgroundColor #000000c2, #00000033 is not transparent values but the hex color has a transparency component. Is this a false error?

C:\apps\python-3.10.7\Scripts\uv.exe run validate-ttml -ttml_in "sub_fin_v4.xml" -results_out "validator-results.txt"
Error: preParse_encoding Unparsed file cp949 encoding found, with no BOM, re-encoding as UTF-8
Error: bbc_block_backgroundColor_constraint 36 locations backgroundColor #00000033 is not transparent (BBC requirement)
Error: bbc_text_fontFamily_constraint 196 locations Computed fontFamily ['Roboto', 'proportionalSansSerif', 'default'] differs from BBC requirement
Error: bbc_text_fontSize_constraint 196 locations Computed fontSize 4.545rh outside BBC-allowed range 6rh-7.5rh
Error: bbc_text_lineHeight_constraint 98 locations Computed lineHeight 5.455rh outside BBC-allowed range 7.200rh-9.000rh
Error: bbc_text_backgroundColor_constraint 98 locations Computed backgroundColor #00000000 not BBC-allowed value
Error: bbc_block_backgroundColor_constraint 38 locations backgroundColor #000000c2 is not transparent (BBC requirement)
Error: bbc_region_position_constraint region element xml:id top Region extends out of BBC-defined permitted area (9.5%-91.5% horizontally and 5%-95% vertically)

ps: No need to worry about the "fontFamily | outside BBC-allowed | BBC-permitted area" error values.

[nigelmegitt]

This looks like a correct error message. The BBC requirement is for a solid (non-transparent) black background colour, and as you observe, the hex color has a transparency (opacity, in fact) component. If present that must have full opacity, i.e. ff but in the reported cases it has a lower value.

Why did you think it might be a false error?

[Murmur]

bbc_block_backgroundColor_constraint 36 locations backgroundColor #33 is not transparent (BBC requirement)

I think misunderstood an error text it says "error: is not transparent" but the meaning is "error: is transparent"