Each file writer that is capable of writing arbitrary metadata is
supposed to tace care to suppress hints meant for other writers, or for
OIIO in general, not interpret them as literal metadata to write to the
file. PNG was not doing so, and ended up writing hints as literal
metadata. This brings it in line with our behavior when writing OpenEXR
and other formats.
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Signed-off-by: Larry Gritz <lg@larrygritz.com>
Larry Gritz
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