PDF শব্দকোষ

Flatten

Flattening merges a PDF's interactive layers — form fields, annotations, and optional content layers — directly into the page content. The document keeps its exact visual appearance, but its fields can no longer be edited or filled in. It is commonly used to lock a completed form before archiving or distribution.

সম্পর্কিত টুল: একটি PDF ফ্ল্যাটেন করুন

Encryption

PDF encryption protects a document's content using a cipher (usually AES 128- or 256-bit) tied to a password. A distinction is made between the user (open) password, required to view the file, and the owner (permissions) password, which restricts printing, copying, or editing. Without the matching key, the content stays unreadable.

সম্পর্কিত টুল: PDF সুরক্ষিত করুন

Compression

Compression reduces a PDF file's size by optimizing its components: downsampling and re-encoding images, removing redundant data, and compressing content streams. It can be lossless, preserving full quality, or lossy, slightly degrading images for a greater size reduction. The goal is to make files easier to share and store.

সম্পর্কিত টুল: PDF কমপ্রেস করুন

CropBox

The CropBox is one of a PDF page's bounding boxes; it defines the visible region that is actually displayed and printed. Unlike the MediaBox, which describes the full physical dimensions of the medium, the CropBox can hide unwanted margins or edges without deleting the underlying content. Adjusting the CropBox therefore crops a page non-destructively.

সম্পর্কিত টুল: একটি PDF ক্রপ করুন

Watermark

A watermark is a semi-transparent text or image overlaid on the pages of a PDF, often diagonally. It is used to indicate a status ("Confidential", "Draft"), to mark a document's ownership, or to discourage unauthorized copying. The watermark can be placed above or below the existing content.

সম্পর্কিত টুল: PDF ওয়াটারমার্ক

Imposition

Imposition is the arrangement of several pages on a single sheet so that they appear in the correct order once folded and bound. In booklet mode, pages are reordered and paired two by two to form a signature folded down the middle. N-up mode instead groups several scaled-down pages onto one sheet, for example for economical printing.

সম্পর্কিত টুল: বুকলেট

Linearization

Linearization, also known as "fast web view", reorganizes a PDF's internal structure so that its first page can be shown before the whole file has downloaded. Objects are reordered and a special index is added to allow progressive rendering and byte-range access to a specific page on a remote server. This is especially useful for large documents viewed online.

সম্পর্কিত টুল: ওয়েবের জন্য অপ্টিমাইজ করুন

Metadata

A PDF's metadata is the descriptive information attached to the document without being part of its visible content: title, author, subject, keywords, creating application, and creation or modification dates. It is stored in the document information dictionary and often in an XMP stream. Viewing or clearing these fields helps to index a file properly or to strip sensitive data from it.

সম্পর্কিত টুল: PDF মেটাডেটা

Bates numbering

Bates numbering is an indexing system that stamps a unique, sequential identifier on every page of a set of documents, often with a prefix and a fixed number of digits. Originating in US legal and administrative practice, it makes it easier to reference, catalog, and track exhibits during a proceeding. Each page thereby becomes unambiguously citable.

সম্পর্কিত টুল: Bates নম্বরকরণ

OCR

OCR (Optical Character Recognition) is a technology that analyzes the image of a scanned document to extract its text as editable characters. Applied to an image-based PDF, it adds an invisible text layer aligned with the words, making the document searchable and selectable. It is essential for turning scans and photographs of documents into searchable files.

সম্পর্কিত টুল: OCR — টেক্সট এক্সট্র্যাকশন

PDF

PDF (Portable Document Format) is a file format created by Adobe that has become an open ISO standard (ISO 32000). It describes a document's layout, text, fonts, images, and vector graphics in a fixed way so that it displays and prints identically regardless of the system used. It is today the reference format for exchanging finalized documents.

PDF/A

PDF/A is a standardized version of PDF (ISO 19005) designed for long-term electronic archiving. It requires that everything needed to render the document faithfully be contained within the file itself — embedded fonts and color information — and forbids externally dependent elements such as links to files or encryption. This ensures a document will remain identically legible decades from now.

সম্পর্কিত টুল: PDF/A-তে রূপান্তর করুন

Embedded font

An embedded font is a typeface whose glyph data is included directly inside the PDF file, ensuring correct display even on a system that does not have that font installed. To keep the file small, only a subset containing the characters actually used is often embedded. Font embedding is essential to the portability and faithful archiving of documents.

সম্পর্কিত টুল: ফন্ট তালিকাভুক্ত করুন

Electronic signature

An electronic signature attaches proof of identity and integrity to a PDF document, making it possible to verify who signed it and that it has not been altered since. The most robust digital signature relies on public-key cryptography and a certificate, whereas a so-called simple signature may amount only to placing an image of a handwritten mark. Its legal weight depends on the level of assurance and the applicable regulatory framework.

সম্পর্কিত টুল: PDF সই করুন