I want to convert a color pdf to black and white pdf in specific mode I want to convert all text in red or green in black (not in gray).

gs -o output.pdf \ -sDEVICE=pdfwrite \ -dBlackText=true \ -dBlackVector=true \ -sColorConversionStrategy=Gray \ -dProcessColorModel=/DeviceGray \ input.pdf

TOON (Token-Oriented Object Notation)

Token-Oriented Object Notation (TOON) is a compact data format designed to reduce token usage when passing structured information to Large Language Models (LLMs), achieving 30-60% fewer tokens compared to standard JSON.

It simplifies syntax by eliminating unnecessary punctuation and using a more readable structure, making it ideal for applications that frequently interact with LLMs

https://github.com/toon-format/toon

Example:

JSON: (41 Token)

{
  "users": [
    { "id": 1, "name": "Alice", "role": "admin" },
    { "id": 2, "name": "Bob", "role": "user" }
  ]
}

TOON: (21 token)

users[2]{id,name,role}:
  1,Alice,admin
  2,Bob,user

User the tool https://toonifyit.com/

F-Droid and Fossify

What is F-Droid? F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.

https://f-droid.org/

Here you can download many apps as:

    sudo apt install imagemagick

Step 2 - Use the following command:

    convert *.jpeg my_pdf.pdf 


The command above might yield an “operation not allowed” error. Fortunately, we
can easily fix it by executing:

sudo sed -i 's/^.*policy.*coder.*none.*PDF.\*//' /etc/ImageMagick-6/policy.xml

or better:

sudo gedit /etc/ImageMagick-6/policy.xml

add or change the row at end of the file (just before </policymap>) with the following:

<policy domain="coder" rights="read | write" pattern="PDF" />

PHP: How to extract emails from list file

 
$pattern = '/[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}/';
if ($file = fopen("a.vcf", "r")) {
    while(!feof($file)) {
        $line = fgets($file);
       if (preg_match($pattern, $line, $matches)) echo $matches[0]."\n";
    }
    fclose($file);
}