Here's the transcript (in a raw form). The task is done when we've done enough to check, improve and share the content.
i think it's always good to bear in mind when when we're um thinking
about pdf um it was originally conceived of as an interchange in
enabler it would bridge different platforms but pdf is at its root a
document description language i'm sorry um oh i'm about to make a
mistake here i hope i'll be forgiven but uh yeah philip was saying
page description language much as dvi is a page description language
and anyone who's ever parsed dvi knows how lacking in in large
contextual uh features that is pdf can be structured with comments but
it's not essentially a way of conveying that sort of information html
as it relates to sgml the notion is that we would structure our
documents by interleaving within the content the characters themselves
some sort of um markup that would provide a context and give meaning
to the essentially to the words the stream of letters and i think epub
gets to do that but pdf has uh built-in limitations it was uh it was
not directed toward that end and pdf was a boon to the publishing
world and people like me who were working professionally there at the
same time i don't think pdf in and of itself is a solution for
accessibility um uh when we start with say a lot tech document we have
a prayer that we might create something that can be used not only to
present page but also can be used to create something that will
provide information to who knows who including say visually impaired
person or whatever and this is where my emphasis on best practices for
document preparation comes into the picture because people who prepare
documents are myriad they're legion and the fact that so many of us
don't have an appreciation of the sort of accessibility issues that
are present for other people we have the privilege of by being able to
ignore the disabled or to ignore how we are disabling people by
preparing the sorts of documentation documents that we do so um i'm
always looking for a way to give assistance to people in preparing
documents that are very very worthy let's call it that valuable
because not only do they provide information to say the sighted or
people who are going to be reading a book but also people who want to
access the document in other ways um my recollection of pdf which is
also in part based upon my experience working in the printing house of
cambridge university press is that it's a boon for printing on paper
so in the early days well actually in the very early days you have
something called the lythostone and lifetime means stones it's stone
with special properties and grease and water don't mix and that allows
you to print without a raised surface because the grease attracts the
ink and the water repels it something like that and then you start to
have photographic processes for putting an image for lithoprinting
onto an aluminium plate so you make a negative and then you'd burn
that negative onto a sensitized aluminium plate and then you develop
the aluminium plate and parts of it attracted in the republic and you
put the sheet value in human to a cylinder and the cylinder revolved
you have this device that um and one device that spread ink onto the
cylinder and another device that took it off and so you only got ink
where you wanted but you had to have this piece of paper to begin with
that you then created a film from and then you and so forth and pdf
allows you to go straight to plate i said all this because pdf allows
you to go straight from plate you can get these things like laser
printers but they produce a printing plate and that's a tremendous
spoon in a in a in a high volume printing process printing print works
[Music] in particular you've got you've reduced the large amount of
the uncertainty in a large amount of the labor and it becomes easier
to keep the printing machines running all the time which is of course
a good thing to do if you're very expensive so pdf is designed for the
print industry and it happened that you could get pdf files that you
could see on your computer and computers got to a point now where you
didn't even have to print them to see to read them so that was
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Here's the transcript (in a raw form). The task is done when we've done enough to check, improve and share the content.
i think it's always good to bear in mind when when we're um thinking about pdf um it was originally conceived of as an interchange in enabler it would bridge different platforms but pdf is at its root a document description language i'm sorry um oh i'm about to make a mistake here i hope i'll be forgiven but uh yeah philip was saying page description language much as dvi is a page description language and anyone who's ever parsed dvi knows how lacking in in large contextual uh features that is pdf can be structured with comments but it's not essentially a way of conveying that sort of information html as it relates to sgml the notion is that we would structure our documents by interleaving within the content the characters themselves some sort of um markup that would provide a context and give meaning to the essentially to the words the stream of letters and i think epub gets to do that but pdf has uh built-in limitations it was uh it was not directed toward that end and pdf was a boon to the publishing world and people like me who were working professionally there at the same time i don't think pdf in and of itself is a solution for accessibility um uh when we start with say a lot tech document we have a prayer that we might create something that can be used not only to present page but also can be used to create something that will provide information to who knows who including say visually impaired person or whatever and this is where my emphasis on best practices for document preparation comes into the picture because people who prepare documents are myriad they're legion and the fact that so many of us don't have an appreciation of the sort of accessibility issues that are present for other people we have the privilege of by being able to ignore the disabled or to ignore how we are disabling people by preparing the sorts of documentation documents that we do so um i'm always looking for a way to give assistance to people in preparing documents that are very very worthy let's call it that valuable because not only do they provide information to say the sighted or people who are going to be reading a book but also people who want to access the document in other ways um my recollection of pdf which is also in part based upon my experience working in the printing house of cambridge university press is that it's a boon for printing on paper so in the early days well actually in the very early days you have something called the lythostone and lifetime means stones it's stone with special properties and grease and water don't mix and that allows you to print without a raised surface because the grease attracts the ink and the water repels it something like that and then you start to have photographic processes for putting an image for lithoprinting onto an aluminium plate so you make a negative and then you'd burn that negative onto a sensitized aluminium plate and then you develop the aluminium plate and parts of it attracted in the republic and you put the sheet value in human to a cylinder and the cylinder revolved you have this device that um and one device that spread ink onto the cylinder and another device that took it off and so you only got ink where you wanted but you had to have this piece of paper to begin with that you then created a film from and then you and so forth and pdf allows you to go straight to plate i said all this because pdf allows you to go straight from plate you can get these things like laser printers but they produce a printing plate and that's a tremendous spoon in a in a in a high volume printing process printing print works [Music] in particular you've got you've reduced the large amount of the uncertainty in a large amount of the labor and it becomes easier to keep the printing machines running all the time which is of course a good thing to do if you're very expensive so pdf is designed for the print industry and it happened that you could get pdf files that you could see on your computer and computers got to a point now where you didn't even have to print them to see to read them so that was