Determine if PDF file has searchable text in PHP - php

We have hundreds of PDF files on a server. Some of them contain searchable text and others do not.
I was asked to find out which are searchable and which are not.
Does anybody know of a way to read in a bunch of PDFs and determine if that PDF document contains text that is searchable/selectable or if the pdf only contains non-selectable/searchable text which needs to be OCRd?
I don't even need to actually read in the text; I just need to be able to detect possibly by tags or keywords, something that suggests that there are fonts or something like that in the raw data.
Are there tags in a searchable PDF that make it easy to detect?
Thanks

You could modify this code(pdf2text) to suit your purposes, I believe. Or this answer might get you to the right spot as well.

Related

Submit HTML form to PDF

We have a high-resolution PDF (for printing) which has some form fields on it. We would like to have an HTML form which submits to the PDF, which is then placed into the respective fields.
I found a solution on google: http://koivi.com/fill-pdf-form-fields/
However, with that solution you only get an FDF file... And the demo does not work for me, opening the FDF file simply downloads another FDF file.
Since this PDF will be available to the public we would like to keep it as simple as possible. If we must open our original PDF and import this FDF file, we need a different solution (which I'm not sure is what the FDF file is for, since it didn't work).
A related post talking about .net framework had the same idea, but there were only paid commercial solutions: From HTML form to PDF
The PHP solutions I have found so far are for creating a new PDF, which is not what I need. Our PDF is created with Adobe Illustrator (or a similar adobe product) and is high-res with embedded fonts, svg and image content.
The form elements are in place, we just need to get the data to there.
Update April 11, 2013:
Since posting this question I have been utilizing FPDF on multiple projects where I needed to accomplish this goal. Although it cannot seem to "merge" template PDFs with the provided data, it can create the PDF from scratch.
One example I have used, I had a high resolution PNG for printing (similar to initial question) which we had to write the customer's name and today's date clearly in the center. I simply made the background of the PDF using FPDF->Image() and write the text afterwards using FPDF->Text().
It was very simple after all, you will need to look up the paper sizes to determine the X,Y,W,H of the image and then base your text fields relative to those numbers.
There was even a Form Filling extension, but I couldn't get it to work.
It seems as though I should answer my own question, although Visions answer may be better (seems to be deleted?). I used Vasiliy Faronov's link which was a comment to my main question: https://stackoverflow.com/a/1890835/200445
Here I found how to install pdftk and run a command to merge (flatten) my FDF and PDF files. I still used the "hacky" way to generate an FDF using Koivi's FDF Generator but it works for the most part.
One caveat is that some characters, like single and double quotes are not inserted correctly. It may be an issue of escaping the fields, but I could not find an answer.
Regardless, my PDF form generator is working, but anyone with a similar issue should look for a better solution.
There are number of tools which are not paid like itextsharp. try the following https://web.archive.org/web/20211020001747/https://www.4guysfromrolla.com/articles/030211-1.aspx Hope this code will help you. I have tried it its worked for me. If you can pay then there are number of paid tools which convert the HtML to PDF like ABCPDF etc.This example is in Asp.net and i am sure if you can convert it in PHP it will work for you too.

PHP - Workaround for reading user-selected text from PDF?

I am working on a project that allows a user to upload text or content from an HTML page in Japanese and then use their cursor to select words in the text/content to translate into English. However, I would like to be able to expand this functionality to PDF files. Essentially, I'd like the user to be able to submit a PDF file and have the browser render that PDF file in such a way that when the user selects/highlights words in the PDF, the browser can somehow relay what the text of the highlighted section is, such as via javascript, to be then relayed to a PHP variable.
I know there are a lot of posts on stackoverflow asking similar questions (I've spent hours upon hours trying to sort through them all!), but I can't seem to find a definitive answer on whether this is possible. It seems there are lots of options for converting PDF to HTML or extracting text from PDF, but to be quite honest, I'm confused if any of those options are relevant to what I am trying to accomplish. And I know there's a javascript API for Adobe, but I'm under the impression the javascript needs to be embedded in the PDF already, which will not be true if the user is uploading their own PDF files to render. Even if that is possible, it seems there's no native text selection support in the Adobe javascript API....
Is there a straightforward workaround (oxymoron?) to doing this? Again, I want to be able to pass text selected in a PDF to a variable -- the effect is the user highlights words they don't know so those words can be added to a word bank for retrieval in a dictionary.
Let me know if I can be clearer on anything. Thank you!
I think your best bet is to convert the PDF to HTML (see this answers) and then you are already set as you already implemented everything for regular HTML.

Embed code in video file

I'm sorry if the question is ambiguous, I'll try to explain.
I'm working on an existing PHP download script for videos and some parts of it are broken. There's code in there that's supposed to place a specific member code inside the video file before download, but it doesn't work. Here's the code:
//embed user's code in video file
$fpTarget = fopen($filename, "a");
fwrite($fpTarget, $member_code);
fclose($fpTarget);
$member_code is a random 6-character code.
Now, this would make sense to me if it were a text file, but since it's a video file, how could this possibly work and what is it supposed to do? If the member code is somehow added to the video, how can I see it after download it? I have no experience with video files, so any help is appreciated (a modification of the available code or new code would be equally welcome).
I'm sorry I can't give a more precise description of what the code is supposed to do, I'm trying to figure that out myself.
It may work, depending on the format/type of the video. MPG files are fairly tolerant of "noise" in a file and players would skip over your code because it doesn't look like valid video frame data.
Other formats/players may puke, because the format requires certain data be at specific offsets relative to the end of the file, which you've now shifted by 6 characters.
Your best bet is to figure see if whatever format you're serving up has provisions for metadata in its specifications. e.g. there might be support for a comment field somewhere that you can simply slap the code into.
However, if you're doing all this for 'security' or tracking unauthorized sharing of the video, then simply writing the number into a header is fairly easy to bypass. A better bet would be to watermark the video somehow so that the code is embedded in the actual video data, so that "This video belongs to member XYZ only" is displayed while playing.
You don't write to the content of the file directly, not like you would with a text file. As you've noticed, this effectively corrupts the video and you have no way of reasonably reading the information.
For audio/video files, you write to meta-data that's packaged with the file. How this is packaged and what you can do with it generally depends heavily on the container format used for the file. (Remember that container and codec are two different things. The codec is the format used to encode the audio/video, the container is the file format in which that data stream is stored.)
A library like getID3 might be a good place to start. I've never used it, but it seems to be what you're looking for. What you would essentially do is write a value to the meta-data in the container (either a pre-defined value for that container or maybe a custom key/value pair, etc.) which would be part of the file. Then, when reading the file, you can get that data. (Now, that last part depends heavily on what's reading the file. The data is there, but not every player cares about it. You'll want to match up what you're writing to with what you usually see/read from the file's internal meta-data.)

Programmatic Way To Link Text Within A PDF

I am looking for some way to code a function (I'm open to any language or library at this point) to take an already existing PDF file as input and return a modified PDF file that links certain words to different URLs. I know PHP and ColdFusion both have good tools for dealing with PDF's, but I haven't been able to find anything that works.
I've been doing this by going through Acrobat and linking the text by hand and was wondering if there was any way to automate the procedure.
Thanks!
With ColdFusion you can extract the text with DDX (see Extracting text from a PDF document on the page), modify it using search/replace and generate new document.
If I understand what you're trying to do, you should be able to use CFPDF (http://livedocs.adobe.com/coldfusion/8/htmldocs/Tags_p-q_02.html#2922772) to read the pdf file into a ColdFusion variable, replace whatever content you want in that variable, then save the content back to pdf.

extracting content from pdf using PHP

Could you please tell me how to extract content from PDF document using PHP? Formatting is the main problem im facing here. So let me know, if there are some ways to extract content with the same format and to display it on an online text editor.
Thanks
Have a look at XPDF
I suppose you could do
$text = shell_exec("pdftotext $pdffile");
As for displaying it in an editor? Well, which editor?
To retain some type of formatting information, and assuming by web editor you mean HTML editor, you can convert it to HTML. Perhaps there are other tools available, but since i use xpdf i came across this converter that is based on xpdf.
Basic usage
pdftohtml -noframes -c test.pdf test.html
To get it into your favorite editor
echo file_get_contents('test.html');
You may need to wrap things inside PHP functions/classes. And you may want to add security measures and whatnot.
As far as I can see, it is not possible to convert a PDF to editable HTML using PHP on the fly, while preserving formatting. There are a number of Desktop apps around that all try to extract data from PDFs with sometimes more, sometimes less reliable results. I would say this is not realistically possible at the moment and all you can do is to extract plain text using XPDF or other command line tools.
It may be different with that new XML-Based PDF format but I don't really know anything about that yet.
Feel free to prove me wrong, of course - I'd be very interested myself if there were a solution.

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