PDF/A, PDF/X, and PDF/UA Output in Delphi: a HotPDF Guide
Generate PDF/A, PDF/X, and PDF/UA compliant files from Delphi with HotPDF: output intents, tagged structure, ICC profiles, and veraPDF verification steps
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Browse PDF, Delphi, and document software engineering notes from losLab
Arabic and RTL Text Shaping in Delphi PDFs with HotPDF
What HotPDF shapes in Delphi PDFs: bidi reordering, Arabic joining, script coverage from Hebrew to Thai and Devanagari, and how to verify the shaped output
Processing Large PDFs in Delphi with the HotPDF Direct File API
Process huge PDFs in Delphi without loading them into memory: HotPDF Direct File API handles, encrypted copy, page counts, and incremental updates
AES-256 PDF Encryption in Delphi: HotPDF Setup and Pitfalls
Set up AES-256 PDF encryption in Delphi with HotPDF: user and owner passwords, permission flags, R5 vs R6 revisions, and the property order that silently fails
XFA to AcroForm Flattening in Delphi Using HotPDF
Convert dynamic XFA forms to native AcroForm in Delphi with HotPDF FlattenLoadedXFA, review flatten warnings, and handle archival and PDF/A limits
Automating PDF Preflight Checks in Delphi with HotPDF
Build an automated PDF preflight gate in Delphi: generate standards-clean files with HotPDF, then verify them with veraPDF and Acrobat before release
PDF Digital Signatures and PAdES in Delphi with HotPDF
Sign PDFs in Delphi with HotPDF: PFX one-call signing, ByteRange reservation for external signers, PAdES baseline fields, and document timestamps
Building AcroForm Fields and Actions with HotPDF in Delphi
Create AcroForm text fields, checkboxes, radio groups, and submit or JavaScript actions in Delphi with HotPDF, and avoid export-value mismatches in form intake
Delphi PDF Reports with HotPDF: TextOut, Fonts, and Images
Practical HotPDF guide to Delphi PDF reports: TextOut coordinates, Unicode font embedding, JPEG and PNG image placement, and drawing primitives that scale
Object Streams and Incremental Updates in Delphi with HotPDF
Cut Delphi PDF size with object streams and xref streams, then append changes as incremental updates with HotPDF while keeping earlier revisions intact
Generate Excel Files in Delphi Without Office Automation
Build XLS and XLSX workbooks from Delphi services without installing Excel: native BIFF and OOXML writers, stream output to HTTP responses, COM-free
HotXLS Formula Engine and Custom Functions in Delphi
Evaluate Excel formulas in Delphi with HotXLS: the Calculate engine, OnUserFunction custom functions, array formulas, and why CSV export needs computed values
Open and Save ODS Files in Delphi with HotXLS
HotXLS opens and saves OpenDocument Spreadsheet files from Delphi: SaveAsODS export options, the lightweight ODS import path, and what survives a round trip
HotXLS Conditional Formatting and Rich Text in Delphi
Apply cellIs rules, data bars, icon sets, and rich text runs from Delphi with HotXLS, avoiding the dxf style and font pool index traps in XLSX files
HotXLS Charts and Images: Excel Drawings in Delphi
How to add Excel charts, images, and shapes from Delphi with HotXLS: chart sheets in XLS, embedded charts and pictures in XLSX, EMU sizing, and anchor traps
Template-Based Excel Report Generation in Delphi with HotXLS
Fill Excel report templates from Delphi with HotXLS: locate placeholders with FindText, clone detail rows, insert rows safely, and recalculate before saving
HotXLS: Workbook Audit and Format Conversion in Delphi
Audit unknown Excel files from Delphi with HotXLS: count charts, formulas, macros, and protection, then convert XLS, XLSX, and ODS with known fidelity limits
Exporting Delphi Datasets to Excel Reports with HotXLS
Export TDataset results to Excel from Delphi with HotXLS: TDataToXLS grouping and paging, the VCL dependency trap, XLSX conversion, and a service-safe loop
HotXLS: Sheet Protection, Page Setup, and Printing in Delphi
Protect worksheets, keep input ranges editable, and control print layout in Delphi with HotXLS: Locked flags, page setup, scaling, and header codes
Large Excel Workbook Performance in Delphi with HotXLS
Practical HotXLS performance tuning for large Excel files in Delphi: StreamingWrite saves, style pool reuse, row callbacks, and faster read-only loads
Export Excel to CSV, TSV, and HTML in Delphi (HotXLS)
Export Excel sheets to CSV, TSV, and HTML from Delphi with HotXLS. Covers RFC 4180 quoting, UTF-8 BOM, and why formulas need Calculate before export
Defined Names and Cross-Sheet Formulas in Delphi (HotXLS)
Create workbook-scoped and sheet-scoped defined names with HotXLS in Delphi, write cross-sheet formulas that survive edits, and avoid _xlnm name conflicts
HotXLS Data Validation, AutoFilter and Tables in Delphi
Add dropdown validation, AutoFilter criteria, and Excel tables from Delphi with HotXLS, including server-side filter preview and the 0-based column ID trap
Excel Comments and Hyperlinks in Delphi with HotXLS
Write cell comments with authors, external URLs, and in-workbook links from Delphi using HotXLS, including the XLSX internal-link API and XLS comment quirks
HotXLS Merged Cells and Report Template Layout in Delphi
How HotXLS handles merged cells in Delphi report templates: anchor-cell semantics, InsertRows shifting rules, merge audits, and HTML and RTF export behavior
HotXLS: Preserve VBA Macros and External Links in Delphi
How HotXLS preserves VBA projects and external links when Delphi code edits XLS and XLSX workbooks: macro-enabled saves, link targets, and round-trip limits
HotXLS Streaming Writes for Delphi Server Batch Jobs
Keep large XLSX exports inside memory limits with HotXLS StreamingWrite, row-level write callbacks, style pool reuse, and per-thread batch workbook jobs
Setting Excel Document Properties in Delphi with HotXLS
Set and read Excel document properties from Delphi with HotXLS: title, author, company, and keywords across BIFF SummaryInformation and OOXML docProps parts
List Sheet Names Fast in Delphi with HotXLS GetSheetNames
Read worksheet names from XLS, XLSX, and ODS files in Delphi without loading cell data: HotXLS GetSheetNames, encrypted-file detection, intake triage
Encrypt XLSX Files with AES in Delphi using HotXLS
Write AES-encrypted XLSX files from Delphi with HotXLS SaveAsEncrypted: ECMA-376 Standard Encryption, password handling, and the write-only decryption limit
Build an Accessible PDF Reader in Delphi with PDFium
Make a Delphi PDF viewer work with screen readers: tagged reading order extraction, word-level TTS highlighting, and honest fallbacks for untagged PDFs
Word-by-Word TTS Highlighting in Delphi PDFium Viewers
Sync text-to-speech with on-page word highlights in Delphi using PDFium word boxes: TrackReadingWordAt, render ordering, auto-scroll, and Unicode pitfalls
Low-Vision PDF Color Filters in Delphi with PDFium
Add dark mode and low-vision reading modes to a Delphi PDF viewer: post-render inversion, two kinds of grayscale, and overlay colors that stay visible
Batch PDF Preflight Reports in Delphi with the PDFium Component CLI
Automate PDF/A and PDF/UA preflight in Delphi with PDFium Component: batch loops, exit codes, JSON and HTML reports, and why empty findings are not a pass
Build a PDF Intake Review Workbench in Delphi with PDFium Component
Triage incoming PDFs in Delphi with PDFium Component: check Info dictionary and XMP metadata, spot encryption, JavaScript, and XFA, and route risky files early
Delphi PDF Annotation Review with PDFium Component
Build a PDF annotation review panel in Delphi: index markup by page, survive appearance-stream vetoes, and recolor or delete annotations without ghosts
PDF Form Field Navigation in Delphi (PDFium Component)
Why filled PDF forms look blank in Acrobat and how to fix it: FormFill setup, keyboard field traversal, and GenerateFormAppearances in Delphi viewers
PDFium Delphi Viewer: Render Cache and Smooth Zoom Tactics
Keep zoom and scrolling smooth in Delphi PDF viewers with PDFium: correct cache keys, bitmap ownership, progressive rendering, and high-DPI memory budgets
Secure PDF Preview in Delphi Applications with PDFium Component
Harden a Delphi PDF preview pane with PDFium Component: disable JavaScript at load, intercept link clicks, filter attachments, and read encryption permissions
PDF Viewer for Lazarus and Free Pascal with PDFium
Port a Delphi PDF viewer to Lazarus and Free Pascal: string encoding traps, runtime form construction, PDFium binary loading, and TTS beyond Windows
Multi-Engine PDF Rendering in Delphi: Built-in, Cairo, and PDFium with PDF Library for Delphi
Switch between built-in, Cairo and PDFium renderers per file in PDF Library for Delphi: engine probes, DPI scaling traps and a fallback chain that logs itself
PAdES Digital Signatures in Delphi: Signing and Validation with PDF Library for Delphi
Produce PAdES B-B, B-T and B-LT signatures with PDF Library for Delphi: timestamp reservations, DSS assembly and ByteRange audits before trusting a file
PDF/A and PDF/UA Preflight in Delphi with PDF Library for Delphi
Run PDF/A and PDF/UA preflight from Delphi with PDF Library for Delphi: structured findings, diffable reports, save-time fixups and veraPDF cross-checks
Merging and Splitting Gigabyte PDFs in Delphi with PDF Library for Delphi Direct Access
Open gigabyte PDFs in milliseconds with PDF Library for Delphi direct access: page handles, streaming merge lists, range extraction and xref repair
PDF Library for Delphi DLL, ActiveX, and dylib Bindings: Calling One PDF Engine from Any Language
PDF Library for Delphi exposes one flat PDF API as a Stdcall DLL, Safecall ActiveX object and Cdecl dylib, and the string and handle traps each binding hides
Text, Image, and Font Extraction from PDF in Delphi with PDF Library for Delphi
Extract positioned text, original image streams and font metadata from PDFs with PDF Library for Delphi, plus extraction options for search and audit jobs
Auditing PDF Encryption and Permissions in Delphi with PDF Library for Delphi
Read the PDF /Encrypt dictionary like an auditor with PDF Library for Delphi: algorithm, key length, AES-256 R5 vs R6, permission bits and Identity filter traps
PDF Library for Delphi Print Preview and Device-Context Output in Delphi
Delphi print preview that matches the printed page: device-context rendering, virtual printers, scaling, and DevMode persistence with PDF Library for Delphi
Building Tagged PDF Structure Trees in Delphi with PDF Library for Delphi
Generate tagged PDFs from Delphi with PDF Library for Delphi: structure trees while drawing, table header semantics, artifacts and PDF/UA diagnostics on save
Building a Compliance and Signing Workbench in Delphi with PDF Library for Delphi
Wire PDF/A preflight, PAdES signing and ByteRange audits into one Delphi workbench with PDF Library for Delphi so the revision you validate is the one you sign
Side-by-Side PDF Comparison in Delphi with PDFium Component
Build a side-by-side PDF viewer in Delphi with PDFium Component using independent panels, per-view TPdfView.Zoom, and synchronized page navigation
Reading PDF Font Properties with PDFium Component in Delphi
Inspect the fonts inside a PDF from Delphi with PDFium Component: read a glyph's family name, base name, weight, italic angle, and whether the face is embedded
PDF Attachments in Delphi with PDFium Component: Read, Add, Delete
Manage PDF attachments in Delphi with PDFium Component using AttachmentCount, Attachment, CreateAttachment, DeleteAttachment, safe paths, and in-place saves
Printing PDF Documents with PDFium Component in Delphi
Print PDFs from Delphi with PDFium Component: render with RenderPage and rePrinting, send bitmaps through StretchDIBits, fit pages, and handle rotation
Creating PDFs from Scratch with PDFium Component in Delphi
Create a PDF from scratch in Delphi with PDFium Component using CreateDocument, AddPage, AddText, and CreatePath while handling coordinates and embedded fonts
Render PDF Pages to JPEG Images in Delphi with PDFium Component
Render PDF pages as JPEG images in Delphi with PDFium Component: convert DPI to pixel dimensions, draw each page to a bitmap, and encode it with TJPEGImage
Splitting PDF Documents with PDFium Component in Delphi
Split a PDF by page, range, or bookmark with PDFium Component in Delphi using TPdf.ImportPages, CreateDocument, checked SaveAs results, and Active resets
Merging Multiple PDF Files into One Document with PDFium Component
Merge PDF files in Delphi with PDFium Component: ImportPages, page range strings, insertion position, silent failure on bad files, and form field behavior
Combine Scanned Images into One PDF with PDFium Component in Delphi
Merge a folder of scanned images into one PDF with PDFium Component in Delphi: create the document, add one page per image, scale each image, and save
Extracting Images from PDFs with PDFium Component in Delphi
Extract embedded PDF images in Delphi with PDFium Component: read BitmapCount, fetch each Bitmap[], handle silent open failures, and save JPEG or BMP output
Extracting Text from PDF Files with PDFium Component in Delphi
Extract PDF text in Delphi with PDFium Component using raw Character[] glyph access, structured ReadablePageContent, and a guard for silent Active failures
Creating a Multi-Page PDF Viewer with Continuous Scrolling in Delphi
Creating a Multi-Page PDF Viewer with Continuous Scrolling in Delphi. This tutorial explores the Multi-Page Viewer demo, which extends the basic PDF viewer
Build a PDF Viewer in Delphi with PDFium Component
Assemble a PDF viewer in Delphi with PDFium Component: connect TPdf to TPdfView, load and render a document, then add paging, zoom, and fit navigation
RtLTextOut in HotPDF: Right-to-Left PDF Text in Delphi
HotPDF RtLTextOut reference for Delphi: signature, parameters, charset 178/177 setup, RegisterUnicodeTTF, a working example, and common RTL errors fixed
Reusing a THotPDF Instance Across Documents in Delphi
One THotPDF instance can write many PDFs in Delphi: how the BeginDoc and EndDoc cycle resets state, when to load a file instead, and how to avoid file locks
PDF Linearization and Fast Web View: How It Works
How PDF linearization (Fast Web View) shows page one before a file finishes loading: the linearization dictionary, hint streams, and why later edits break it
Master PDF Structure: XML Metadata, Bookmarks & Annotations
Master PDF Structure: XML Metadata, Bookmarks & Annotations. Understanding PDF XML Metadata and Bookmarks: A Technical Guide Key Topics Covered 📍
PDF Text and Font Handling with Code Examples and Best Practices
PDF Text and Font Handling with Code Examples and Best Practices. Mastering PDF Text and Fonts: A Developer’s Guide PDF documents have revolutionized how
PDF Graphics Explained: Understanding PDF Visual Elements
PDF Graphics Explained: Understanding PDF Visual Elements. PDF Graphics: From Basic Paths to Advanced Visual Effects Discover the fascinating world of PDF
Understanding PDF File Structure: A Technical Overview
Understanding PDF File Structure: A Technical Overview. Inside PDF Files: A Complete Structural Breakdown The Portable Document Format (PDF) has become the
Understanding PDF: The Universal Document Format
Understanding PDF: The Universal Document Format. PDF – The Document Format That Changed Everything Every day, millions of people open PDF files without
Optimizing PDF Processing Performance: From Minutes to Seconds
Optimizing PDF Processing Performance: From Minutes to Seconds. From Minutes to Seconds in PDF Handling Applications PDF processing performance can make or
PDF Without a Pages Dictionary: Parsing Implications
ISO 32000 requires every PDF Catalog to have a /Pages entry. Without it parsers crash or count zero pages; recovery means scanning every object for /Type /Page
Range Check Errors in Delphi PDF Libraries: Root Causes
Range check errors in Delphi PDF libraries: why compound boolean conditions bypass bounds checks, and why page object storage order is the real root cause
PDF Page Trees: Page Order, Fan-Out, and /Count Integrity
How the PDF /Pages tree sets display order, why writers nest it, how inherited attributes and a lying /Count break page code, and how to read it safely
PDF Page Order Pitfalls: Physical vs Logical Structure
Copying page 1 returns page 2 when a loader builds its page array in file object order. Why the /Kids array defines page order and how HotPDF follows it
losLab PDF Library: A Comprehensive Feature Guide
Unleashing the Power of losLab PDF Library: A Comprehensive Feature Guide losLab PDF Library is a robust PDF Software Development Kit (SDK) that provides
Transforming RTF Files into PDF: A Guide for Developers
Transforming RTF Files into PDF: A Guide for Developers. Transforming RTF Files into PDF: A Guide for Delphi, C# & VB
Scaling PDF Pages by 70% using losLab PDF Library, in Delphi, C# & VB.Net
Scaling PDF Pages by 70% using losLab PDF Library, in Delphi, C# & VB.Net. When working with PDFs, there are often requirements to scale the content for
Set TDateTimePicker format in Delphi 5
Use DateTime_SetFormat in Delphi 5 when TDateTimePicker.Format is unavailable, and keep newer Delphi versions on the direct Format property
Port Delphi _ftol inline assembly to 64-bit builds
Why Delphi 64-bit builds reject inline asm for _ftol, when to prefer Trunc, and how to avoid porting fragile 32-bit assembly into DCC64
Fix Delphi E2010 tagLOGBRUSH and tagLOGBRUSH32 incompatible types
Fix Delphi E2010 incompatible types between tagLOGBRUSH and tagLOGBRUSH32 by copying EMR brush fields into TLogBrush before calling CreateBrushIndirect
Create and Free a HotPDF Delphi Component Dynamically in C++Builder
Allocate and release a THotPDF instance at runtime in C++Builder: owner semantics, try/__finally cleanup, include path setup, and AutoLaunch pitfalls
HotPDF Canvas Drawing in Delphi: Vector Paths and Color
Draw vector shapes in a PDF from Delphi with HotPDF: paths with MoveTo and LineTo, stroke and fill, RGB color, line width, in a top-left coordinate system
Render a Data Table to PDF in Delphi with HotPDF
Draw dataset rows as a real PDF table in Delphi: compute column widths, align cell text, draw grid lines, and repeat the header when the table spans pages
Drawing Charts in a PDF with HotPDF Primitives
HotPDF has no chart object, so you draw bar, line, and pie charts yourself with Rectangle, LineTo, and Circle in Delphi. Here is the coordinate math and layout
Generating Scannable Barcodes in PDF with HotPDF in Delphi
Draw linear barcodes into a PDF from Delphi with HotPDF: the symbologies it supports, how module width and quiet zone decide whether a scanner can read it
HotPDF Delphi Hyperlinks: PrintHyperlink Annotation Tips
HotPDF Delphi hyperlinks: PrintHyperlink URI links, AddURILink hotspots, AddGoToLink internal page navigation, multi-line link labels, and PDF/UA notes
PDF Annotations in Delphi with HotPDF: Types and Rects
Add PDF annotations in Delphi with HotPDF: text notes, free text, squares, and stamps. How a rect places each one and how they differ from AcroForm fields
CJK Vertical Text in PDF with Delphi and HotPDF
Lay out CJK vertical text in PDF from Delphi with HotPDF: use IsVertical in SetFont, stack glyphs downward, fix U+30FC, and arrange columns right to left
HotPDF TextOut in Delphi: Size, Style, Rotation, and Spacing
Go past Hello World with HotPDF TextOut in Delphi: set font size and style, rotate by angle, place coordinates exactly, and tune character and word spacing
Delphi HotPDF Hello World: Your First PDF Program
Write your first PDF in Delphi with HotPDF: a minimal console Hello World that sets a Unicode font, draws text with TextOut, and saves a compressed file