Re: IPP, JPEG, Exif and dimensions

Hi

It is hard to argue that always going to PWG or URF raster is better.
With potentially fewer and fewer JPEGs qualifying to be sent directly, i
guess direct JPEG printing is almost becoming obsolete.
(And fewer JPEGs in circulation in general).
Though i suspect that there are at least some printers that have JPEG but
not a raster format support.
And presumably a purpose-built photo printer will do a good job with a
straight JPEG.

So i do stand by that my lossless baselinifier has a point, but i should
probably have left my latest silly experiment out of the backstory.
You are quite right, x/y might be different than what is imaged if the user
says to make it so.
But the core of the question remains; what does the IPP attributes indicate:
The jpeg stream contents or the image after rotation according to the Exif
header?
One would need to know that to ascertain if the JPEG can be sent as-is or
not.

A real-world example:
Pictures from my phone are "3000x4000" if i ask basically any normal
application, but libjpeg and "file" see the JPEG data dimensions, which are
actually 4000x3000.
If a printer has max jpeg dimensions of 3000x4000, can i send it the image?

>  There might be "valid" reasons why the hardware can't handle (for
example) long scanlines but can otherwise handle decoding tall images.
Alright, reasonable point; but for that to hold true it would imply that
the x and y dimensions meant are those of the JPEG data, not those after
Exif-ordered/suggested transformation.
So problem solved?

> Official definition of what?
If the x/y dimensions in the spec are those of the JPEG data or those that
a user would normally consider the dimensions of the image when viewed
(i.e. after Exif transformation).

> I encourage you to grab images from a digital camera and not necessarily
from a smartphone, since smartphones often do a lot of post-processing and
use something other than JPEG as a primary storage format.  If you don't
have access to such files I am happy to send you some examples.

To do what do you mean? See how badly i destroy it with my scaling?
So Android has something different now too?
I wouldn't know; i've been on Sailfish OS for 12 years and Meego before
that. :)
That would be appreciated, i don't think i have anything reasonably modern
in that department.

Br,
Anton

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