Pdf -- how to create pixel-only pdfs?

[Markus Robert Kessler]

Hi all,

does anyone know how to create a pdf file containing only pixel
information, and not vector data?

Reason behind:
Some neigbours are asking for permission to use my parking space, when I
am not there, and hence I'd like to email them some pdf with the
permission to use space number x from date1 to date2.
They can print the file and put it into their cars.

But, I don't want anybody to be able to modify starting / ending time
easily. This can be done in Gimp anyway, of course, but everyone would be
aware, that this is criminal.

Any easy way to convert or export from (Libre / Open) Office?

Thanks in advance!

Best regards,

Markus

[Markus Robert Kessler]

Post by Markus Robert Kessler
Hi all,
does anyone know how to create a pdf file containing only pixel
information, and not vector data?
Some neigbours are asking for permission to use my parking space, when I
am not there, and hence I'd like to email them some pdf with the
permission to use space number x from date1 to date2.
They can print the file and put it into their cars.
But, I don't want anybody to be able to modify starting / ending time
easily. This can be done in Gimp anyway, of course, but everyone would
be aware, that this is criminal.
Any easy way to convert or export from (Libre / Open) Office?
Thanks in advance!
Best regards,
Markus

Hi,

forgot to mention that

convert tmp.pdf tmp.png ; convert tmp.png tmp_new.pdf

indeed eliminates all vector info and creates a true pixel-only pdf, but
the quality is crappy.

Other solutions known?

Best regards,

Markus

[Paul]

Post by Markus Robert Kessler

Post by Markus Robert Kessler
Hi all,
does anyone know how to create a pdf file containing only pixel
information, and not vector data?
Some neigbours are asking for permission to use my parking space, when I
am not there, and hence I'd like to email them some pdf with the
permission to use space number x from date1 to date2.
They can print the file and put it into their cars.
But, I don't want anybody to be able to modify starting / ending time
easily. This can be done in Gimp anyway, of course, but everyone would
be aware, that this is criminal.
Any easy way to convert or export from (Libre / Open) Office?
Thanks in advance!
Best regards,
Markus

Hi,
forgot to mention that
convert tmp.pdf tmp.png ; convert tmp.png tmp_new.pdf
indeed eliminates all vector info and creates a true pixel-only pdf, but
the quality is crappy.

OK, why not pass in a resolution parameter and a page size ?

The resolution parameter goes in the *first* command.

The page size declaration goes in the *second* command.

convert -density 600 dog.pdf dog.png

convert -page 612x792 dog.png bitdog.pdf <=== Oh, well. This is NOT going to work.
The Imagemagick forum shows they
don't have a clue over there.
Jaggy city.

dog.png ==> LO-writer insert image, ExportAsPDF ==> bitdog.pdf seems to work...

Pull dog.png into a new LO Writer document,
with letter size paper, "Export As" to PDF,
and then that's the bitdog.pdf .

When you use a desktop publishing tool, it takes
the 5100x6600 dog.png and places every pixel into
the 512x792 Letter page. This requires having a scale
factor applied to the image inside LO. When the
page is exported in a WYSIWYG fashion, the right
thing happens, the jaggies will be reduced compared
to how Imagemagick was doing it. Like this:

Here is bitdog.pdf zoomed in, to show the density
setting is making a difference. And if you set it
too high, the printer may run out of RAM during
the page print.

Loading Image...

Paul

[William Unruh]

Post by Markus Robert Kessler

Post by Markus Robert Kessler
Hi all,
does anyone know how to create a pdf file containing only pixel
information, and not vector data?
Some neigbours are asking for permission to use my parking space, when I
am not there, and hence I'd like to email them some pdf with the
permission to use space number x from date1 to date2.
They can print the file and put it into their cars.
But, I don't want anybody to be able to modify starting / ending time
easily. This can be done in Gimp anyway, of course, but everyone would
be aware, that this is criminal.
Any easy way to convert or export from (Libre / Open) Office?
Thanks in advance!
Best regards,
Markus

Hi,
forgot to mention that
convert tmp.pdf tmp.png ; convert tmp.png tmp_new.pdf

You probably need to tell convert to use a higher pixel/inch setting
than the default.

Post by Markus Robert Kessler
indeed eliminates all vector info and creates a true pixel-only pdf, but
the quality is crappy.
Other solutions known?
Best regards,
Markus

[William Unruh]

Post by Markus Robert Kessler
Hi all,
does anyone know how to create a pdf file containing only pixel
information, and not vector data?

Pictures in pdf are jpeg. So you could just put in pictures (which are
pictures).

Post by Markus Robert Kessler
Some neigbours are asking for permission to use my parking space, when I
am not there, and hence I'd like to email them some pdf with the
permission to use space number x from date1 to date2.
They can print the file and put it into their cars.
But, I don't want anybody to be able to modify starting / ending time
easily. This can be done in Gimp anyway, of course, but everyone would be
aware, that this is criminal.

And doing it in text is also criminal.
Have them send you a copy of the signed permission, at which point you
have the evidence that they got the permissions and the dates.
But if you do not trust your neighbors why are you giving them
permission to park?

Post by Markus Robert Kessler
Any easy way to convert or export from (Libre / Open) Office?

Save as png or jpeg and then use convert to make a pdf.

[Daniel65]

William Unruh wrote on 16/08/2020 10:46 AM:

<Snip>

Post by William Unruh
And doing it in text is also criminal.
Have them send you a copy of the signed permission, at which point you
have the evidence that they got the permissions and the dates.
But if you do not trust your neighbors why are you giving them
permission to park?

William, I'm reading Markus' problem as him not only giving Tenant-1
permission but then also wanting Tenant-1 to be able to show Tenant-2,
etc, that he, Tenant-1, has Markus' permission to park in Markus' spot!

[William Unruh]

Post by Daniel65
<Snip>

Post by William Unruh
And doing it in text is also criminal.
Have them send you a copy of the signed permission, at which point you
have the evidence that they got the permissions and the dates.
But if you do not trust your neighbors why are you giving them
permission to park?

William, I'm reading Markus' problem as him not only giving Tenant-1
permission but then also wanting Tenant-1 to be able to show Tenant-2,
etc, that he, Tenant-1, has Markus' permission to park in Markus' spot!

Yes, but then Tenant-1 can print out the PDF file saved from Libreoffice
Writer to show them. His concern is that Tenant-1 might alter the dates
in the PDF file and print out a document which allows Tenant-1 to part
there at other times as well. It is that skulduggery which He seems to
want to prevent by making the PDF be a bitmap rather than a text based
PDF. And it was his concern about the Tenant-1's intent that he is
(pretty ineffectively as he admits) trying to make more difficult to
impliment. There would seem to be two things which he might concern
him: One is that Tenant-1 parks there (with an altered permission
document) when (the OP) has given permission to Tenant-2 (or the OPs
mother) to park there,
Two is that Tenant-1 alters the document to park there when the OP is
home and wants to park there.

If he suspects Tenant-1 to do these things, it is a bit unclear why he
would allow Tenant-1 to use the spot at all. And Tenant-1 could just
manufacture a permission out of whole cloth in those cases anyway.

If it becomes a matter of calling in an outside referee (Strata Council,
Police, the courts) then having a copy signed by Tenant-1 agreeing to
the dates would seem to be what is needed. Or just making sure that
Tenant-1 is trustworthy in the first place.

[Daniel65]

Post by William Unruh

Post by Daniel65
<Snip>

Post by William Unruh
And doing it in text is also criminal.
Have them send you a copy of the signed permission, at which point you
have the evidence that they got the permissions and the dates.
But if you do not trust your neighbors why are you giving them
permission to park?

William, I'm reading Markus' problem as him not only giving Tenant-1
permission but then also wanting Tenant-1 to be able to show Tenant-2,
etc, that he, Tenant-1, has Markus' permission to park in Markus' spot!

Yes, but then Tenant-1 can print out the PDF file saved from Libreoffice
Writer to show them. His concern is that Tenant-1 might alter the dates
in the PDF file and print out a document which allows Tenant-1 to part
there at other times as well. It is that skulduggery which He seems to
want to prevent by making the PDF be a bitmap rather than a text based
PDF. And it was his concern about the Tenant-1's intent that he is
(pretty ineffectively as he admits) trying to make more difficult to
impliment. There would seem to be two things which he might concern
him: One is that Tenant-1 parks there (with an altered permission
document) when (the OP) has given permission to Tenant-2 (or the OPs
mother) to park there,
Two is that Tenant-1 alters the document to park there when the OP is
home and wants to park there.
If he suspects Tenant-1 to do these things, it is a bit unclear why he
would allow Tenant-1 to use the spot at all. And Tenant-1 could just
manufacture a permission out of whole cloth in those cases anyway.
If it becomes a matter of calling in an outside referee (Strata Council,
Police, the courts) then having a copy signed by Tenant-1 agreeing to
the dates would seem to be what is needed. Or just making sure that
Tenant-1 is trustworthy in the first place.

I suppose your last line is where I'm coming from ... If I can't trust
the guy to do the right thing, why would I help out in the first place!