Re: SANE_FRAME_IR

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We already have a SANE_FRAME_JPEG and SANE_FRAME_IR in sane.h, but they are
commented out because we could not agree on bumping the library version
number. I bet you could find some ancient, and sometimes heated discussions
in the archives of this mailing list.

allan

On Wed, Jul 22, 2026 at 7:49=E2=80=AFPM Benjamin Gordon <bmgordon@chromium.=
org>
wrote:

> On Wed, Jul 22, 2026 at 11:33=E2=80=AFAM Ralph Little <[email protected]=
> wrote:
>
>> Hi,
>> We have had a question from a developer regarding support for IR from a
>> scanner, namely the LS-5000 supported by the coolscan3 backend.
>> This device can supply IR but there are a few different ways in which
>> this can be delivered to the frontend. The brief discussion is here:
>> https://gitlab.com/sane-project/backends/-/merge_requests/937
>>
>> As I said in that discussion, I believe the SANE_FRAME_IR option (or
>> some variant) is the better one to explicitly support it from the SANE
>> standard. I assume that this was a proposed extension at some point.
>> However, this would mean we would need to ratify a new standard and ask
>> frontend developers to support the new features, something that we might
>> struggle to do ourselves what with the backlog we currently have.
>>
>> There are mentioned some other options, such as delivering the IR frame
>> as grey in the next frame, which is done currently by another backend,
>> and has the advantage of being supported right now.
>>
>> Views? Any appetite for an update to the SANE Standard? I'm sure there
>> are a few things that people would like to add.
>>
>
> If there's the possibility of re-opening the standard, I for one would
> like to consider a more general handling of frame formats.  All the
> scanners that support eSCL these days can return JPEG directly, and some =
of
> them can even return a whole PDF at once.  It would be great for the
> frontend to be able to negotiate some sort of passthrough mode instead of
> decoding these and then re-encoding in the frontend.
>
> Thanks,
> Benjamin
>
>

--=20
"well, I stand up next to a mountain- and I chop it down with the edge of
my hand"

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<div dir=3D"ltr"><div>We already have a SANE_FRAME_JPEG and=C2=A0SANE_FRAME=
_IR in sane.h, but they are commented out because we could not agree on bum=
ping the library version number. I bet you could find some ancient, and som=
etimes heated discussions in the archives of this mailing=C2=A0list.</div><=
div><br></div><div>allan</div></div><br><div class=3D"gmail_quote gmail_quo=
te_container"><div dir=3D"ltr" class=3D"gmail_attr">On Wed, Jul 22, 2026 at=
 7:49=E2=80=AFPM Benjamin Gordon &lt;<a href=3D"mailto:[email protected]=
g">[email protected]</a>&gt; wrote:<br></div><blockquote class=3D"gmail=
_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204=
,204);padding-left:1ex"><div dir=3D"ltr"><div dir=3D"ltr"><span style=3D"ba=
ckground-color:transparent">On Wed, Jul 22, 2026 at 11:33=E2=80=AFAM Ralph =
Little &lt;<a href=3D"mailto:[email protected]" target=3D"_blank">skelband=
@gmail.com</a>&gt; wrote:</span></div><div class=3D"gmail_quote"><blockquot=
e class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px s=
olid rgb(204,204,204);padding-left:1ex">Hi,<br>
We have had a question from a developer regarding support for IR from a <br=
>
scanner, namely the LS-5000 supported by the coolscan3 backend.<br>
This device can supply IR but there are a few different ways in which <br>
this can be delivered to the frontend. The brief discussion is here: <br>
<a href=3D"https://gitlab.com/sane-project/backends/-/merge_requests/937" r=
el=3D"noreferrer" target=3D"_blank">https://gitlab.com/sane-project/backend=
s/-/merge_requests/937</a><br>
<br>
As I said in that discussion, I believe the SANE_FRAME_IR option (or <br>
some variant) is the better one to explicitly support it from the SANE <br>
standard. I assume that this was a proposed extension at some point. <br>
However, this would mean we would need to ratify a new standard and ask <br=
>
frontend developers to support the new features, something that we might <b=
r>
struggle to do ourselves what with the backlog we currently have.<br>
<br>
There are mentioned some other options, such as delivering the IR frame <br=
>
as grey in the next frame, which is done currently by another backend, <br>
and has the advantage of being supported right now.<br>
<br>
Views? Any appetite for an update to the SANE Standard? I&#39;m sure there =
<br>
are a few things that people would like to add.<br></blockquote><div><br></=
div><div>If there&#39;s the possibility of re-opening the standard, I for o=
ne would like to consider a more general handling of frame formats.=C2=A0 A=
ll the scanners that support eSCL these days can return JPEG directly, and =
some of them can even return a whole PDF at once.=C2=A0 It would be great f=
or the frontend to be able to negotiate some sort of passthrough mode inste=
ad of decoding these and then re-encoding in the frontend.</div><div><br></=
div><div>Thanks,</div><div>Benjamin</div><div><br></div></div></div>
</blockquote></div><div><br clear=3D"all"></div><br><span class=3D"gmail_si=
gnature_prefix">-- </span><br><div dir=3D"ltr" class=3D"gmail_signature">&q=
uot;well, I stand up next to a mountain- and I chop it down with the edge o=
f my hand&quot;</div>

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