How to check PDF DPI

How to check PDF DPI

Hi ,
I am using the html2pdf PHP lib. to create PDF file which contents
text and images.
I want to check DPI of that generated PDF.
is there any tool or way to check that

Thanks
Pravin.

Re: How to check PDF DPI

Pravin wrote:

> I am using the html2pdf PHP lib. to create PDF file which contents
> text and images.
> I want to check DPI of that generated PDF.
> is there any tool or way to check that

PDF is in general an vector format and is therefore not affected by the
"resolution-problem". Only embedded images, bitmap fonts and similar things
have their own resolution. But that is individually to each embedded item
and does not apply to the pdf itself.

Robert

Re: How to check PDF DPI

Pravin wrote:
> Hi ,
> I am using the html2pdf PHP lib. to create PDF file which contents
> text and images.
> I want to check DPI of that generated PDF.
> is there any tool or way to check that
> 
> Thanks
> Pravin.

You can check the resolution of images with the Preflight Tool of Adobe 
Acrobat.

Re: How to check PDF DPI

Robert (and other PDF experts ... ),

I have heard that said before -- PDF is resolution independent -- but
I haven't quite understood that.

Here is what is confusing me.

On my PDF software export, I have 3 options:

Highest quality (for hi-quality printing)
Laser printing quality
Smallest size (for viewing PDF on the web)

Most of my documents in PDF have NO images; so what is the difference
between these three versions of PDF -- if that difference is not
"resolution" ?

This problem has been confusing me for a long time !

Thanks very much,

RW

Re: How to check PDF DPI

booklover wrote:
> Robert (and other PDF experts ... ),
> 
> I have heard that said before -- PDF is resolution independent -- but
> I haven't quite understood that.
> 
> Here is what is confusing me.
> 
> On my PDF software export, I have 3 options:
> 
> Highest quality (for hi-quality printing)
> Laser printing quality
> Smallest size (for viewing PDF on the web)

This probably refers to images only.

> Most of my documents in PDF have NO images; so what is the difference
> between these three versions of PDF -- if that difference is not
> "resolution" ?

Probably no difference at all. Have you tried it and made a comparison?

///Peter

Re: How to check PDF DPI

On Nov 21, 6:14=A0pm, Peter Flynn <peter.n...@m.silmaril.ie> wrote:
>
> Probably no difference at all. Have you tried it and made a comparison?
>
> ///Peter

Yes, I did -- after I got your message.

For 2 pages of text, with no images:

+ Smallest size (for viewing PDF on the web)  ... around 16 KB
+ Laser printing quality ...
around 47 KB
+ Highest quality (for hi-quality printing) ...          around 145 KB
+ Highest quality + tagged PDF  ...                       around 150
KB

Thanks, Peter

RW

Re: How to check PDF DPI

booklover wrote:
> On Nov 21, 6:14 pm, Peter Flynn <peter.n...@m.silmaril.ie> wrote:
>> Probably no difference at all. Have you tried it and made a comparison?
>>
>> ///Peter
> 
> Yes, I did -- after I got your message.
> 
> For 2 pages of text, with no images:
> 
> + Smallest size (for viewing PDF on the web)  ... around 16 KB
> + Laser printing quality ...
> around 47 KB
> + Highest quality (for hi-quality printing) ...          around 145 KB
> + Highest quality + tagged PDF  ...                       around 150
> KB
> 
> Thanks, Peter
> 
> RW
Can you post links to the samples?

Re: How to check PDF DPI

> Can you post links to the samples?

Thank you for asking.

Here is a link to a zipped folder that contains the 4 PDF files that
I've just made:

http://www.box.net/shared/lr5t35e13i

From this page, click the big DOWNLOAD link, unzip and then you will
see the 4 files.

There are 4 PDF files inside only; nothing else.

RW

Re: How to check PDF DPI

booklover schrieb:
>> Can you post links to the samples?
> 
> Thank you for asking.
> 
> Here is a link to a zipped folder that contains the 4 PDF files that
> I've just made:
> 
> http://www.box.net/shared/lr5t35e13i
> 
> From this page, click the big DOWNLOAD link, unzip and then you will
> see the 4 files.
> 
> There are 4 PDF files inside only; nothing else.
> 
> RW
> 

I can see following differences:

test-pdf-003-high.pdf    - fonts are full embedded

test-pdf-002-medium.pdf  - fonts embedded with subsets

test-pdf-001-smallest    - fonts not embedded

Re: How to check PDF DPI

Thank you, Bernd. I am starting to understand this a little better.

Does anyone know if it is possible to change a PDF (from one of these
three types, to another type) ?

Or must that kind of setting be made, as I did, in the source file
that is not a PDF file ?

Thanks again,

RW

On Nov 22, 4:38=A0pm, Bernd Alheit <be_9...@yahoo.de> wrote:
> booklover schrieb:
> I can see following differences:
>
> test-pdf-003-high.pdf =A0 =A0- fonts are full embedded
>
> test-pdf-002-medium.pdf =A0- fonts embedded with subsets
>
> test-pdf-001-smallest =A0 =A0- fonts not embedded

Re: How to check PDF DPI

At Sun, 22 Nov 2009 22:38:23 +0100 Bernd Alheit <be_9002@yahoo.de> wrote:

> 
> booklover schrieb:
> >> Can you post links to the samples?
> > 
> > Thank you for asking.
> > 
> > Here is a link to a zipped folder that contains the 4 PDF files that
> > I've just made:
> > 
> > http://www.box.net/shared/lr5t35e13i
> > 
> > From this page, click the big DOWNLOAD link, unzip and then you will
> > see the 4 files.
> > 
> > There are 4 PDF files inside only; nothing else.
> > 
> > RW
> > 
> 
> I can see following differences:
> 
> test-pdf-003-high.pdf    - fonts are full embedded
> 
> test-pdf-002-medium.pdf  - fonts embedded with subsets
> 
> test-pdf-001-smallest    - fonts not embedded

Right.  None of these affect the *formatting* or the dot resolution of
the text.  The first is more 'portable' and is what publishers want, the
last one is great for on-line access, where minimuzing download time and
disk usage is desirable.  You only *need* fonts to be embedded if you are
NOT using one of the 14 'standard' Adobe fonts.

>                         

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Download the Model Railroad System
http://www.deepsoft.com/  -- Binaries for Linux and MS-Windows
heller@deepsoft.com       -- http://www.deepsoft.com/ModelRailroadSystem/
                                                                    

Re: How to check PDF DPI

Thank you, Bernd and Robert ! ... I am getting the picture about text
in PDF.

About images in PDF:

1. When we talk about the resolution in PDF, we are talking about the
dpi of the included images?  Yes / No

2. When two or more images are included in one PDF file, then the
resolution of these images must be the same dpi: if one image is 300
dpi, then another image cannot be 72 dpi ?  Yes / No

3. When a PDF file has text but not searchable or editable text (let's
say: that a book page is scanned but is not OCR converted: just
scanned to PDF) -- then does this PDF file have a resolution -- just
as if the scan of the book's page had been the scan of a
photograph? ... Yes / No

Thanks again for the help !

RW

Re: How to check PDF DPI

booklover wrote:
> Thank you, Bernd and Robert ! ... I am getting the picture about text
> in PDF.
> 
> About images in PDF:
> 
> 1. When we talk about the resolution in PDF, we are talking about the
> dpi of the included images?  Yes / No

Yes

> 2. When two or more images are included in one PDF file, then the
> resolution of these images must be the same dpi: if one image is 300
> dpi, then another image cannot be 72 dpi ?  Yes / No

No, different images can have different resolutions

> 3. When a PDF file has text but not searchable or editable text (let's
> say: that a book page is scanned but is not OCR converted: just
> scanned to PDF) -- then does this PDF file have a resolution -- just
> as if the scan of the book's page had been the scan of a
> photograph? ... Yes / No

When scan a book page you will get one image for this page

> Thanks again for the help !
> 
> RW

Re: How to check PDF DPI

At Mon, 23 Nov 2009 10:24:38 +0100 Bernd Alheit <be_9002@yahoo.de> wrote:

> 
> booklover wrote:
> > Thank you, Bernd and Robert ! ... I am getting the picture about text
> > in PDF.
> > 
> > About images in PDF:
> > 
> > 1. When we talk about the resolution in PDF, we are talking about the
> > dpi of the included images?  Yes / No
> 
> Yes
> 
> > 2. When two or more images are included in one PDF file, then the
> > resolution of these images must be the same dpi: if one image is 300
> > dpi, then another image cannot be 72 dpi ?  Yes / No
> 
> No, different images can have different resolutions
> 
> > 3. When a PDF file has text but not searchable or editable text (let's
> > say: that a book page is scanned but is not OCR converted: just
> > scanned to PDF) -- then does this PDF file have a resolution -- just
> > as if the scan of the book's page had been the scan of a
> > photograph? ... Yes / No
> 
> When scan a book page you will get one image for this page

Unless the scanning is followed by OCR (Optical Character Recognition).

> 
> > Thanks again for the help !
> > 
> > RW
>                                                                                  

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Download the Model Railroad System
http://www.deepsoft.com/  -- Binaries for Linux and MS-Windows
heller@deepsoft.com       -- http://www.deepsoft.com/ModelRailroadSystem/
                                                                            

Re: How to check PDF DPI

Thank you very much, again, Bernd and Robert.

And thanks once more, for any help with this last question:

How can I learn more about PDF ?

RW

Re: How to check PDF DPI

At Mon, 23 Nov 2009 07:26:41 -0800 (PST) booklover <robinwhitman@gmail.com> wrote:

> 
> Thank you very much, again, Bernd and Robert.
> 
> And thanks once more, for any help with this last question:
> 
> How can I learn more about PDF ?

Adobe has the spec book available for download.  Or you can buy a hard copy
from Amazon.com.

> 
> RW
>                                                                                                           

-- 
Robert Heller             -- 978-544-6933
Deepwoods Software        -- Download the Model Railroad System
http://www.deepsoft.com/  -- Binaries for Linux and MS-Windows
heller@deepsoft.com       -- http://www.deepsoft.com/ModelRailroadSystem/
        

Re: How to check PDF DPI

On Nov 21, 6:14=A0pm, Peter Flynn <peter.n...@m.silmaril.ie> wrote:
>
> Probably no difference at all. Have you tried it and made a comparison?
>
> ///Peter

Yes, I did -- after I got your message.

For 2 pages of text, with no images:

+ Smallest size (for viewing PDF on the web)  ... around 16 KB
+ Laser printing quality ...
around 47 KB
+ Highest quality (for hi-quality printing) ...          around 145 KB
+ Highest quality + tagged PDF  ...                       around 150
KB

Thanks, Peter

RW