Hi Thomas

Embedded overlays (in the "unused" high bits) are not supported
by any of the image compression transfer syntaxes, like JPEG
or JPEG 2000, so these aren't supported for JPIP either, since
it is just a means of transferring JPEG 2000 data ... the number
of bits passed through the compression/decompression cycle is
intended to defined by Bits Stored (only), which excludes the
overlay bits. This is not terribly clearly expressed in the
standard though.

The use of (60xx,3000) Overlay Data to separately encode overlay
bits is independent of the transfer syntax and would work with
the JPIP transfer syntax, since the overlays data would be sent
with the "header" in the normal way, not retrieved as JPIP
coefficients.

David

PS. The use of embedded overlay bits has been retired as of
Sup 98, so folks should go out of their way to avoid using
them, and if presented with them in an instance that they
are going to transcode (e.g., compress), should probably
move the overlay to (60xx,3000) or into a presentation
state.

Thomas Sondergaard wrote:
> Hi,
>
> Can overlays still be encoded in the pixel data when the JPEG-2000/JPIP
> transfer syntax is used?
>
> regards,
>
> Thomas