How can I get past the gray background? How to change a PDF file without a special program Open the file with the Soda PDF Online program

How can I get past the gray background?

Master's note:

Often, if you scan that chi and other documentation, the background of the image appears simulta- neously. The recognition of that robot with documents is becoming foldable. Use a copy of the receipt of the purification of similar documents in pdf and djvu formats.

Required: ScanKromsator program.

ScanKromsator vikorisovuetsya for a gray background from otrimanih scans. You can download this program on the official website of retailers at the address djvu-soft.narod.ru/soft/#scan. Choose the required version of the program. Click on the message "Zavantage".

Install the program on the computer. To view a gray background from a pdf and djvu file, open it in ScanCromsator. Go to program settings, set the ensign for the Enhance image option, click on the "Gray enhance" button, you can also change it to the hot key B.

In the Background cleaner tab, set the background cleaner. For which, set the Cleaner passes parameter to a value that equals one. Tse allow you to see the background of the scan. For example, between the color text and the photo in the document, there is already an insignificant contrast, set the ensign next to the Correct low contrast parameter, which allows you to improve the sensitivity of recognizing textual information on a gray background.

Correct the values ​​20-25, step by step changing the value by 5. After the ScanCromsator sees the background of the scanned image, it also changes the file for clarity to the text, the contrast of some background color is closer to the specified threshold of sensitivity or more. If the given value is found, then the color of such a point will either not be changed, or it will be replaced by pure black.

Let's go to the Quality tab. By clicking on the “Enhance” button, set the Cleaner passes parameter to a value that equals one. Take the ensign from the Protect black pixels option. Fill in the illustrations with color, which are in the scan, put in the Exclude zone, for them to protect from the poshkodzhennya.

Quickly preview the results of cleaning up the gray background by using the Preview with resample button in the Quality tab. Choose the appropriate Sensitivity value (from 5 to 30) for the gray background. The stronger the contrast between the background and the text, the greater the value of the parameter, set. Now go to the window Protect black, turn off yoga.

2

It is impossible to build without using a cost-free software security, or a cost-free tool, which I know about. (Because in the wild you happen to change mustache color in PDF-sides, and not just the background itself, so you can check the contrast and color of the interior.)

What you described for Adobe Reader does not change the PDF itself, but changes the way the sides are displayed (by inverting colors or similar). PDF is subject to permanent review after review.

Prote maybe be able to access the same, zastosovuyuchi vydpovidny color ICC profile for the introduction of PDF and viroblyat for help (albeit a new version)

get rid of food: what IS "valid" ICC color Profile for your purpose??

I briefly looked at the siro-ish background in PDF format for the help of pdftk... background... command line. Ale tse, ymovіrno, zrobit deyakі or a lot of PDF-files are unreadable. (A black the background, insanely, makes it unreadable, so much black text will be left out like that.)

To create an A4 PDF side that could serve as a background, you can highlight Ghostscript: gs -o gray.pdf -sDEVICE=pdfwrite -g5950x8420 -c ".8 setgray 0 0 595 842 rectfill showpage" .

Then paste it back to the original PDF (A4): pdftk original.pdf background gray.pdf output orig-with-backgr.pdf .

To give respect, that the background of these sides will change only (or those of the sides of the sides), we will see through yak greater text based on PDF files. Tse will be not work for the sides of both regions, de background - opaque white or color.)

You can also achieve a permanent change of color (colours) easily for the help of ImageMagick, but you will also chew and work the minced meat of your receiving vector PDF files, converting them to the sides of a full bitmap image: convert nice.pdf -alpha off -invert inverted- colors-ugly-raster.pdf.

Nareshti, here is an inappropriate way to do it, so that you can convert colors inverted for the help of Ghostscript. Vin set color transfer function for output PDF file:

Gs -o output.pdf \-sDEVICE=pdfwrite \-c "(1 exch sub)(1 exch sub)(1 exch sub)(1 exch sub) setcolortransfer" \-f input.pdf

It's undesirable, more non-leather PDF viewer how to install. I reverberated tse kіlka once at the past ...

Qi starers DO NOT SHOW inverted colors:

1. Adobe Reader
2. Adobe Acrobat
3. ghostscript/gs
4. Wake up Chrome PDF Renderer ( "pdfium")

qi tі DO NOT SHOW inverted colors:

1. Chrome with pdf.js
2. Firefox from pdf.js
3. Zathura
4. MuPDF

0

As an addendum to your needs, perhaps, there are tools such as PitStop or pdfToolbox (advance - affiliation), as they can stop such a transfer curve, as only a little more (in other words, unravel new colors and improve the transfer curve). Tse zrobilo yogo postіynim and, then, accessible to all gazing people :) - David van Driessche 29 quarters 15 2015-04-29 22:20:55

0

@DavidvanDriessche: Like, Devide, I’m *mav on the street, that I didn’t know about the yak “Vilne” (like with freedom), or “vilne” (like with a free form), I know ... I will forget Guess commercial utilities, if you want to know, if I wrote my opinion. - Kurt Pfeifle 29 quarters 15 2015-04-29 22:29:25

3

About every vipadok OP is not true the need to change the color of a PDF document postyno, or if you want PDF- peephole krim Acrobat, so you can change the colors that you see.

MuPDF: MuPDF is a lightweight PDF browser (medium). Vіn can be inverted in order to change colors with a simple move i for any document, documents of vіn vіdkritiy. MuPDF is also available for Windows (iOS, i Android, i OSX, i Linux). (This is broken by your own company, as Ghostscript brought us).

MuPDF screenshots here: "normal" view (left-handed) and "inverted" view (right-handed)

SumatraPDF: This is a popular alternative to PDF revision for Windows. The PDF rendering engine is based on MuPDF. Hit. in presentation mode, change the background to black. By pressing w on the presentation mode, w will change the background to white. (I don't think you can invert all colors, but I can't keep the rest of the version available right away, so you can convert it.) To run after adding -invert-colors to the command line, invert colors for the rendered document.

Zathura: Lightweight PDF viewer for Linux and OSX, which can be used for Vim help keys. ctrl+r refactoring the visualization of any open document. The background is changed to dark, the texts are changed to light blue (prote wine is not inverted a, for example, blue text to yellow, as if to break MuPDF). I'm not sure what is available on Windows.

evince: The Gnome PDF viewer is available for Linux, OSX and Windows. You can also invert the colors of the original document; keyboard shortcut: ctrl + i.

XPDF: XPDF - get an ancient PDF viewer for Unix + Linux (not sure if Cygwin has Windows version). Vіn mає parameter to run in the command line: xpdf -rv -papercolor "#333333" file.pdf invert colori (-rv for return video, -papercolor allows you to change the background to look like pure black [shards of the future]).

2

Since you asked for the API, I will add one more possibility to the mix. You can actually write a plug-in for Adobe Acrobat (maybe for Adobe Reader, but also Reader foldable plug-ins) that you want to see.

A long time ago I wrote code for Enfocus PitStop to implement a wireframe rendering mode for PDF files in the middle of Adobe Acrobat. Press the button and the display changes to the frame, press again, and you have a great look. This is why you can (like a plugin) edit the list of visualizations (list of objects), ink for Acrobat help.

This means that for painting your special mode of fermentation, you can create a new list of fermentation (or change the current one), so that you can use a rectangle at the back of the color, whichever you want, and then change the color of your objects . .

It's worth it's foldable, it's more foldable: if you don't want your changes to be added to PDF on disk, you're to blame for changing Acrobat's impersonal reminder and saying your changes. For example, as if you are trying to save a PDF-file for an hour, I’ll review the mode of respite, you are guilty of reconciliation, so that you will be warned about it and said to change the hour of saving. We can work with Adobe Acrobat, so that we can help you before and after the process of saving, but then, as before, a serious work, so that you can change it, so that nothing is screwed up.

Ale is absolutely healthy and has a great way to realize what was good. Just change your mind, what do you have two more days to realize yoga :)

Edit PDF files online
bezkoshtovno at any place

How to edit a PDF file

To grab, drag the file from the field higher. You can also capture a document from your computer or in the dark.

Axis as a practical universal PDF editor. Zliva you bachite miniatures of the sides. Choose the one that needs to be edited. Above the side in the review mode, you need to select the need for a day. There are also available addendums (say, turn the change, improve). To change the color or font, open the Options menu.

Edit PDF Documents Online

To edit an Adobe PDF file, you don't need to change anything or install it. Just tag PDF2Go online studio - no cost!

Forget about shkidlivі programs and viruses, don't clog hard drive. Edit a PDF-document online and edit the finished file!

Need a new PDF editor?

Would you like to add icons to the PDF file? Can you see the most important part of the main paragraph? Surely, you will have to unpack the file ...

And the axis i ni! You can draw on PDF2Go files, add images and watermarks, and also cut and copy other parts of the document.

Edit with us - it's safe

Don't worry about security! All files uploaded to PDF2Go are processed automatically. You only have access to a shared file.

All power rights to the PDF file are reserved to you.

If you run out of food, please read the Privacy Policy.

Can you edit a PDF file?

Good! PDF2Go allows you to edit PDF files - tables, images, text.

Edit PDF files in any convenient place

You don't need a computer to edit PDF documents. The name PDF2Go speaks for itself. Everything you need is only connected to the border.

PDF2Go works on smartphones, tablets, computers and laptops with such browsers as Chrome, Opera, Safari, Firefox and not only!

That wonderful Swedish way edit PDF file— for the help of detailed instructions to beat without cost and available for all online services. A great plus is that you do not happen to buy or install paid editors for Windows or Mac OsX and convert other formats.

The process is even simpler: capture your PDF and make the necessary edits in the browser, then simply capture the changes document back to your computer.

Tool to help you remove the original text from the document, put a watermark, add writing and little things. Regardless of those who have English service, you can easily figure it out, and our instruction will help you to edit a PDF file without difficulties.

1. Go to service. Upload your new document by pressing the big button on the main page "Edit Your PDF Now" and choosing "Add PDF Now" in the menu: Your file will be uploaded successfully, so it will not be larger than 10 Mb and should be less than 100 sides. When you expand, if you are not satisfied with your mind, speed up the PDF and edit in parts, then join.
2. shob edit the PDF document, and delete part of the text itself select “Whiteout” for the new one and expand the rectangular area, if you want to fill in the document, but if it didn’t, press the DEL button above the sheet:
   
3. shob edit the PDF document, and add a new text to the new one, select the “Text” button and use the mouse to place the area near the place, where it is necessary to instruct the necessary words of the speech. To change the size and color of the font, change the menu to the top:
   
4. Now we will tell you, yak. You need to see a clear image, or write a visible picture on a transparent background with PNG extensions (how easy it is to do this). Also, the "Image" button will help you add an image to the document. Capture the image, and then click on the document with the left button of the bear:
   
5. Having sorted out the tools described in the preceding paragraphs, you can also add to PDF send to the site, or be it a side document. Robite tse offensive rank - right-click select the "Link" button in the menu, see the area on the side for attaching the message and in the window choose either the URL (for linking to the site), or the Page to link to the other side of the PDF document (optionally choose the side number):
   
6. To save that zavantazhennya ready file know the right-handed vertically stashed icons, you need green with arrows. Interested? I live!