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Posted to users@pdfbox.apache.org by Matteo Gamboz <ga...@medialab.sissa.it> on 2019/02/21 08:59:08 UTC
resize inline images
Hi all,
I must resize (change the resolution) of some Inline Images in a PDF.
I'm a bit stuck on how best to proceed.
I've tried by extending PDFStreamEngine and overriding method
processOperator (https://stackoverflow.com/q/54744038/1581629) but
without good results.
Since I want to modify a stream (I think), I would like to ask if the
approach is correct or if there are better methods (e.g. extend
GraphicsOperatorProcessor or something...)
thanks
m
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3D slicing functionality
Posted by Tilman Hausherr <TH...@t-online.de>.
Please don't hijack existing threads with a different topic.
And this is not a mailing list about features in Adobe Acrobat. Adobe
has its own discussion website(s) for this. This is a mailing list about
Apache PDFBox.
Tilman
Am 22.02.2019 um 03:59 schrieb Noble 3D Printers, LLC:
> Hi all!
> Does anyone know if it's possible to add 3D slicing functionality to
> acrobats 3D file capability?
> Thanks!
>
> On Thu, Feb 21, 2019, 12:59 AM Matteo Gamboz <ga...@medialab.sissa.it>
> wrote:
>
>> Hi all,
>>
>> I must resize (change the resolution) of some Inline Images in a PDF.
>>
>> I'm a bit stuck on how best to proceed.
>>
>> I've tried by extending PDFStreamEngine and overriding method
>> processOperator (https://stackoverflow.com/q/54744038/1581629) but
>> without good results.
>>
>> Since I want to modify a stream (I think), I would like to ask if the
>> approach is correct or if there are better methods (e.g. extend
>> GraphicsOperatorProcessor or something...)
>>
>> thanks
>> m
>>
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>> To unsubscribe, e-mail: users-unsubscribe@pdfbox.apache.org
>> For additional commands, e-mail: users-help@pdfbox.apache.org
>>
>>
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Re: resize inline images
Posted by "Noble 3D Printers, LLC" <ay...@gmail.com>.
Hi all!
Does anyone know if it's possible to add 3D slicing functionality to
acrobats 3D file capability?
Thanks!
On Thu, Feb 21, 2019, 12:59 AM Matteo Gamboz <ga...@medialab.sissa.it>
wrote:
> Hi all,
>
> I must resize (change the resolution) of some Inline Images in a PDF.
>
> I'm a bit stuck on how best to proceed.
>
> I've tried by extending PDFStreamEngine and overriding method
> processOperator (https://stackoverflow.com/q/54744038/1581629) but
> without good results.
>
> Since I want to modify a stream (I think), I would like to ask if the
> approach is correct or if there are better methods (e.g. extend
> GraphicsOperatorProcessor or something...)
>
> thanks
> m
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@pdfbox.apache.org
> For additional commands, e-mail: users-help@pdfbox.apache.org
>
>
Re: resize images (XObjects, Inline Images and stencils)
Posted by Tilman Hausherr <TH...@t-online.de>.
Hi,
There is at least one bug:
if (image.isStencil()) {
stencil = " (stencil)";
bufferedImageType = BufferedImage.TYPE_BYTE_BINARY;
}
************
if (image.getColorSpace() == PDDeviceGray.INSTANCE){
bufferedImageType = BufferedImage.TYPE_BYTE_GRAY;
}
The problem is that stencils are of colorspace DeviceGray despite being
bitonal. So you need to put an "else" at the "************" place to
avoid the image getting the TYPE_BYTE_GRAY for stencils.
And this:
if (image.isStencil()) {
log.warn("Is stencil; painting red.");
bImage = image.getStencilImage(Color.red);
// ↑ this is problematic...
// it appears to paint the whole stencil
// like it's filling the stencil's "holes" also
is definitively wrong, you are "applying" the stencil, this is for
PDFBox itself when rendering. Just get the image itself and later set
the flag.
This is just a "dry" analysis, I didn't run your code.
Tilman
Am 27.03.2019 um 14:28 schrieb Matteo Gamboz:
> Hi Tilman,
>
> thank you for the corrections (and sorry for the delay in answering, I
> was working on other projects...).
>
> I've applied your suggestions and I think they fixed most of my
> problems. Here is the code as I have it now:
> https://medialab.sissa.it/nextcloud/index.php/s/FiWX3F7TJDbCT5A
>
> One can call the script with some command line options to play with
> different resolutions.
>
> In the source of the java file, one can find how to call the script
> https://medialab.sissa.it/nextcloud/index.php/s/FiWX3F7TJDbCT5A?path=%2Fsrc%2Fmain%2Fjava%2Fit%2Fsissa%2Fmedialab%2Fpdfimages
>
> I don't have much experience with java, please be patient if I was
> supposed to "deploy" the code in some other way :-)
>
>
> As you pointed out, I still have some problems with stencils:
> my process transforms the stencil into an image, but sometimes the
> background of the stencil is black instead of white. You can seen an
> example in the file screenshot.png. The screenshot refers to
> test-files/d.pdf.
>
> I will work on this an keep the list posted.
> m
>
>
> On Fri, 08 Mar 2019 15:59:39 +0100,
> Tilman Hausherr wrote:
>> InputStream img_data_stream = helper_img.getCOSObject().createRawInputStream();
>> ...
>> newBIoperator.setImageParameters(helper_img.getCOSObject());
>>
>>
>> Another thing you should fix yourself. If the image is a stencil,
>> create a TYPE_BYTE_BINARY BufferredImage (and later call
>> setStencil()). If the image is of colorspace DeviceGray, create a
>> TYPE_BYTE_GRAY BufferedImage. I not, then RGB, NOT ARGB.
>>
>> Please fix that also try finding a PDF that has an inline image where
>> something can be seen, the current one is white.
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Re: resize images (XObjects, Inline Images and stencils)
Posted by Matteo Gamboz <ga...@medialab.sissa.it>.
Hi Tilman,
thank you for the corrections (and sorry for the delay in answering, I
was working on other projects...).
I've applied your suggestions and I think they fixed most of my
problems. Here is the code as I have it now:
https://medialab.sissa.it/nextcloud/index.php/s/FiWX3F7TJDbCT5A
One can call the script with some command line options to play with
different resolutions.
In the source of the java file, one can find how to call the script
https://medialab.sissa.it/nextcloud/index.php/s/FiWX3F7TJDbCT5A?path=%2Fsrc%2Fmain%2Fjava%2Fit%2Fsissa%2Fmedialab%2Fpdfimages
I don't have much experience with java, please be patient if I was
supposed to "deploy" the code in some other way :-)
As you pointed out, I still have some problems with stencils:
my process transforms the stencil into an image, but sometimes the
background of the stencil is black instead of white. You can seen an
example in the file screenshot.png. The screenshot refers to
test-files/d.pdf.
I will work on this an keep the list posted.
m
On Fri, 08 Mar 2019 15:59:39 +0100,
Tilman Hausherr wrote:
>
> InputStream img_data_stream = helper_img.getCOSObject().createRawInputStream();
> ...
> newBIoperator.setImageParameters(helper_img.getCOSObject());
>
>
> Another thing you should fix yourself. If the image is a stencil,
> create a TYPE_BYTE_BINARY BufferredImage (and later call
> setStencil()). If the image is of colorspace DeviceGray, create a
> TYPE_BYTE_GRAY BufferedImage. I not, then RGB, NOT ARGB.
>
> Please fix that also try finding a PDF that has an inline image where
> something can be seen, the current one is white.
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Re: resize inline images
Posted by Tilman Hausherr <TH...@t-online.de>.
Am 05.03.2019 um 09:54 schrieb Matteo Gamboz:
> I must yet fix the image parameters to correctly represent the new
> image data, but it seems feasible.
operator.getImageParameters():
COSDictionary{COSName{IM}:true;COSName{W}:COSInt{114};COSName{H}:COSInt{73};COSName{BPC}:COSInt{1};COSName{F}:COSName{CCF};COSName{DP}:COSDictionary{COSName{K}:COSInt{-1};COSName{Columns}:114;};}
helper_img:
COSDictionary{COSName{Length}:COSInt{23};COSName{Type}:COSName{XObject};COSName{Subtype}:COSName{Image};COSName{Filter}:COSName{FlateDecode};COSName{BitsPerComponent}:COSInt{8};COSName{Width}:COSInt{31};COSName{Height}:COSInt{20};COSName{ColorSpace}:COSName{DeviceRGB};COSName{DecodeParms}:COSDictionary{COSName{BitsPerComponent}:8;COSName{Predictor}:COSInt{15};COSName{Columns}:31;COSName{Colors}:COSInt{3};};COSName{SMask}:COSDictionary{COSName{Length}:COSInt{26};COSName{Type}:-1148588617;COSName{Subtype}:70760763;COSName{Filter}:1578622202;COSName{BitsPerComponent}:8;COSName{Width}:31;COSName{Height}:20;COSName{ColorSpace}:COSName{DeviceGray};}COSStream{-856922952};}COSStream{-84829761}
You are running this:
newBIoperator.setImageParameters(operator.getImageParameters());
So you're taking the parameter of the old image to the new image. This
is problematic (may be my fault!), the size isn't the same, the filter
isn't the same, the bitspercomponent isn't the same. And then there's
the problem that your original image is a mask, so the new one should be
too, so the new one should also be a bitonal image but it isn't.
I made two changes:
//InputStream img_data_stream =
helper_img.createInputStream();
InputStream img_data_stream =
helper_img.getCOSObject().createRawInputStream();
This is because the raw stream is when the filter have been applied.
...
//newBIoperator.setImageParameters(operator.getImageParameters());
newBIoperator.setImageParameters(helper_img.getCOSObject());
Another thing you should fix yourself. If the image is a stencil, create
a TYPE_BYTE_BINARY BufferredImage (and later call setStencil()). If the
image is of colorspace DeviceGray, create a TYPE_BYTE_GRAY
BufferedImage. I not, then RGB, NOT ARGB.
Please fix that also try finding a PDF that has an inline image where
something can be seen, the current one is white.
After all these are done, please upload your code and source PDF again.
Tilman
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Re: resize inline images
Posted by Matteo Gamboz <ga...@medialab.sissa.it>.
sorry, here they are
https://medialab.sissa.it/nextcloud/index.php/s/Pdn5CYFcbjoAWsp
On Sun, 03 Mar 2019 15:14:22 +0100,
Tilman Hausherr wrote:
>
> There wasn't anything attached. You can't attach PDFs anyway, these
> must be uploaded to a sharehoster.
>
> Tilman
>
> Am 28.02.2019 um 17:41 schrieb Matteo Gamboz:
> > ...
> >> Please retry there strategy where you had the closing error (fix the
> >> bug I mentioned), and post enough code and upload the source and
> >> result PDFs.
> > Hi Tilman, thank you for the comments and suggestions.
> >
> > I think I'm reaching a good point; my approach is now as follows:
> > . extend PDFStreamEngine and process all operators,
> > . when I find an Inline Image, save away its transformation matrix
> > . after finishing with the operators, I parse the page into tokens
> > . and scan through the tokens
> > . when I find the BI operator
> > . I use the transformation matrix (saved before)
> > . and generate a new image,
> > . then I substitute the BI token with the new image
> >
> > I must yet fix the image parameters to correctly represent the new
> > image data, but it seems feasible.
> >
> > If anyone is interested, I'm attaching my last code and an example pdf
> > that I'm trying to modify. If you spot any obvious mistake I would be
> > grateful for suggestions :-)
> >
> > m
> >
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: users-unsubscribe@pdfbox.apache.org
> > For additional commands, e-mail: users-help@pdfbox.apache.org
>
>
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Re: resize inline images
Posted by Tilman Hausherr <TH...@t-online.de>.
There wasn't anything attached. You can't attach PDFs anyway, these must
be uploaded to a sharehoster.
Tilman
Am 28.02.2019 um 17:41 schrieb Matteo Gamboz:
> ...
>> Please retry there strategy where you had the closing error (fix the
>> bug I mentioned), and post enough code and upload the source and
>> result PDFs.
> Hi Tilman, thank you for the comments and suggestions.
>
> I think I'm reaching a good point; my approach is now as follows:
> . extend PDFStreamEngine and process all operators,
> . when I find an Inline Image, save away its transformation matrix
> . after finishing with the operators, I parse the page into tokens
> . and scan through the tokens
> . when I find the BI operator
> . I use the transformation matrix (saved before)
> . and generate a new image,
> . then I substitute the BI token with the new image
>
> I must yet fix the image parameters to correctly represent the new
> image data, but it seems feasible.
>
> If anyone is interested, I'm attaching my last code and an example pdf
> that I'm trying to modify. If you spot any obvious mistake I would be
> grateful for suggestions :-)
>
> m
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@pdfbox.apache.org
> For additional commands, e-mail: users-help@pdfbox.apache.org
Re: resize inline images
Posted by Matteo Gamboz <ga...@medialab.sissa.it>.
...
> Please retry there strategy where you had the closing error (fix the
> bug I mentioned), and post enough code and upload the source and
> result PDFs.
Hi Tilman, thank you for the comments and suggestions.
I think I'm reaching a good point; my approach is now as follows:
. extend PDFStreamEngine and process all operators,
. when I find an Inline Image, save away its transformation matrix
. after finishing with the operators, I parse the page into tokens
. and scan through the tokens
. when I find the BI operator
. I use the transformation matrix (saved before)
. and generate a new image,
. then I substitute the BI token with the new image
I must yet fix the image parameters to correctly represent the new
image data, but it seems feasible.
If anyone is interested, I'm attaching my last code and an example pdf
that I'm trying to modify. If you spot any obvious mistake I would be
grateful for suggestions :-)
m
Re: resize inline images
Posted by Tilman Hausherr <TH...@t-online.de>.
Am 22.02.2019 um 09:41 schrieb Matteo Gamboz:
> Hi Tilman,
>
>> Did you understand them?
> sort of...
> (please be patient, I think I'm making some confusion :-)
>
> following your suggestion, I was able to create and add another Inline
> Image with the desired resolution into my pdf (I check with "pdfimages
> -list" from poppler-utils):
>
> PDImageXObject helper_img = LosslessFactory.createFromImage(document, scaledImage);
> InputStream img_data_stream = helper_img.createInputStream();
> byte [] img_data = IOUtils.toByteArray(img_data_stream);
> PDInlineImage replacement_img = new PDInlineImage(operator.getImageParameters(),
> img_data,
> resources);
>
> I'm not sure about the "filters" you mentioned...
> I used the same parameters as the original (operator.getImageParameters()).
The filters are the compression... for inline images, shorter names are
available, but I just saw that this is not required, so don't bother.
> Then I appended my new image to the page stream but this way I get two
> inline images... (if I use Appended.OVERWRITE I end up removing all
> other operators from the stream)
Yes, that is not surprising. (both) So you have to choose which one.
>
> PDPageContentStream pageContentStream = new PDPageContentStream(document,
> currentPage,
> AppendMode.APPEND,
> false,
> true);
> pageContentStream.drawImage(replacement_img, 0, 0);
> pageContentStream.close();
>
>
>
> I tried other approaches:
> . (right after creating my replacement_img)
> take the content stream of the current page,
> parse it, get a list of tokens
> run through the list of tokens
> and build a new list
> omitting "BI" operator & co.
> create a new stream from the tokens
> and set it to the page
> (BUT: I have an error about some not-closed stream when saving)
Then you should investigate that. For example, in
helper_img.createInputStream();
You didn't close the stream there.
IMHO you could insert the new BI stuff at the place where the old one was.
>
> . adapt example RemoveAllText.java
> similar to the above: run through the tokens and modify those
> related to images
> (BUT: I'm not sure how to get to the image XObject from the token)
That is a name, just before "Do". That one you'll find in the resources.
>
> . extend GraphicsOperatorProcessor
> (copying from operator.graphics.BeginInlineImage)
> i.e. create a StreamEngine to process my adapted "BeginInlineImage" operator
> (BUT: I get a ClassCastException on the StreamEngine I use)
Hmm, don't know about that one. Postpone that idea.
>
> I think some of the problems are because I've used java ~15 years ago
> and forgot about it until now :-)
>
>
> Since I think I don't really get the hang of the library,
> I have a different (exploratory) proposition.
>
> Let's say that I generally want to
> "change resolution of raster images"
> would you (or anyone else) be interested in writing the appropriate
> code under compensation?
Maybe someone else, but not me.
No because it sounds like a project with risks, and because I have a day
job. But I'll still try to help a bit here (for free!). I think it is
possible, but I expect some surprises. E.g. if the size changes.
The problem is that PDF isn't really made for editing.
Please retry there strategy where you had the closing error (fix the bug
I mentioned), and post enough code and upload the source and result PDFs.
Tilman
> I think that the code could be added to the examples in the source.
> At the moment I do not have any budget, but if we can come up with a
> sum I could try and ask my boss...
>
> I like this kind of approach because I would be able to:
> . get what I want in the short term,
> . learn the best way to do it (so that next time I can do it myself),
> . contribute materially to pdfbox
> . and add valuable piece of "documentation" (the example) to the library.
> . (bonus) have someone else maintain that code
> (I just hope my boss will feel the same :-)
>
> If you (or anyone else) feel this proposal is inappropriate, please
> let me know it and just forget about this.
>
> m
>
>
> On Thu, 21 Feb 2019 18:49:16 +0100,
> Tilman Hausherr wrote:
>> Hi, did you try the two things I mentioned on stackoverflow? (Did you
>> understand them?) Did you create a PDF file with it? If yes, please
>> share it, I might be able to tell what is missing.
>>
>> Tilman
>>
>> Am 21.02.2019 um 09:59 schrieb Matteo Gamboz:
>>> Hi all,
>>>
>>> I must resize (change the resolution) of some Inline Images in a PDF.
>>>
>>> I'm a bit stuck on how best to proceed.
>>>
>>> I've tried by extending PDFStreamEngine and overriding method
>>> processOperator (https://stackoverflow.com/q/54744038/1581629) but
>>> without good results.
>>>
>>> Since I want to modify a stream (I think), I would like to ask if the
>>> approach is correct or if there are better methods (e.g. extend
>>> GraphicsOperatorProcessor or something...)
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Re: resize inline images
Posted by Matteo Gamboz <ga...@medialab.sissa.it>.
Hi Tilman,
> Did you understand them?
sort of...
(please be patient, I think I'm making some confusion :-)
following your suggestion, I was able to create and add another Inline
Image with the desired resolution into my pdf (I check with "pdfimages
-list" from poppler-utils):
PDImageXObject helper_img = LosslessFactory.createFromImage(document, scaledImage);
InputStream img_data_stream = helper_img.createInputStream();
byte [] img_data = IOUtils.toByteArray(img_data_stream);
PDInlineImage replacement_img = new PDInlineImage(operator.getImageParameters(),
img_data,
resources);
I'm not sure about the "filters" you mentioned...
I used the same parameters as the original (operator.getImageParameters()).
Then I appended my new image to the page stream but this way I get two
inline images... (if I use Appended.OVERWRITE I end up removing all
other operators from the stream)
PDPageContentStream pageContentStream = new PDPageContentStream(document,
currentPage,
AppendMode.APPEND,
false,
true);
pageContentStream.drawImage(replacement_img, 0, 0);
pageContentStream.close();
I tried other approaches:
. (right after creating my replacement_img)
take the content stream of the current page,
parse it, get a list of tokens
run through the list of tokens
and build a new list
omitting "BI" operator & co.
create a new stream from the tokens
and set it to the page
(BUT: I have an error about some not-closed stream when saving)
. adapt example RemoveAllText.java
similar to the above: run through the tokens and modify those
related to images
(BUT: I'm not sure how to get to the image XObject from the token)
. extend GraphicsOperatorProcessor
(copying from operator.graphics.BeginInlineImage)
i.e. create a StreamEngine to process my adapted "BeginInlineImage" operator
(BUT: I get a ClassCastException on the StreamEngine I use)
I think some of the problems are because I've used java ~15 years ago
and forgot about it until now :-)
Since I think I don't really get the hang of the library,
I have a different (exploratory) proposition.
Let's say that I generally want to
"change resolution of raster images"
would you (or anyone else) be interested in writing the appropriate
code under compensation?
I think that the code could be added to the examples in the source.
At the moment I do not have any budget, but if we can come up with a
sum I could try and ask my boss...
I like this kind of approach because I would be able to:
. get what I want in the short term,
. learn the best way to do it (so that next time I can do it myself),
. contribute materially to pdfbox
. and add valuable piece of "documentation" (the example) to the library.
. (bonus) have someone else maintain that code
(I just hope my boss will feel the same :-)
If you (or anyone else) feel this proposal is inappropriate, please
let me know it and just forget about this.
m
On Thu, 21 Feb 2019 18:49:16 +0100,
Tilman Hausherr wrote:
>
> Hi, did you try the two things I mentioned on stackoverflow? (Did you
> understand them?) Did you create a PDF file with it? If yes, please
> share it, I might be able to tell what is missing.
>
> Tilman
>
> Am 21.02.2019 um 09:59 schrieb Matteo Gamboz:
> > Hi all,
> >
> > I must resize (change the resolution) of some Inline Images in a PDF.
> >
> > I'm a bit stuck on how best to proceed.
> >
> > I've tried by extending PDFStreamEngine and overriding method
> > processOperator (https://stackoverflow.com/q/54744038/1581629) but
> > without good results.
> >
> > Since I want to modify a stream (I think), I would like to ask if the
> > approach is correct or if there are better methods (e.g. extend
> > GraphicsOperatorProcessor or something...)
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Re: resize inline images
Posted by Tilman Hausherr <TH...@t-online.de>.
Hi, did you try the two things I mentioned on stackoverflow? (Did you
understand them?) Did you create a PDF file with it? If yes, please
share it, I might be able to tell what is missing.
Tilman
Am 21.02.2019 um 09:59 schrieb Matteo Gamboz:
> Hi all,
>
> I must resize (change the resolution) of some Inline Images in a PDF.
>
> I'm a bit stuck on how best to proceed.
>
> I've tried by extending PDFStreamEngine and overriding method
> processOperator (https://stackoverflow.com/q/54744038/1581629) but
> without good results.
>
> Since I want to modify a stream (I think), I would like to ask if the
> approach is correct or if there are better methods (e.g. extend
> GraphicsOperatorProcessor or something...)
>
> thanks
> m
>
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