ENG Drawing Viewer 2.3.1

ENG Drawing Viewer 2.3.1 for Macs with Apple silicon, Windows x64 and Linux x86-64. A free, offline workspace for engineering drawings: view folders of PDF drawings and images sharply at any zoom, mark them up with numbered review comments, turn them into PowerPoint slides, edit images, vectors and PDFs, and use 32 PDF tools, all on your own computer.

ENG Drawing Viewer is free software under the GNU Affero General Public License v3 or later.

Download

File	For
ENG-Drawing-Viewer-macOS-Apple-Silicon.dmg	Mac with Apple silicon (M1 or newer), macOS 14.4 or later
ENG-Drawing-Viewer-Windows-x64.zip	Windows 10 (1809) or 11, 64-bit. Portable, no installer
ENG-Drawing-Viewer-Linux-x86_64.AppImage	Linux x86-64 with glibc 2.34 or newer (Ubuntu 22.04+, Debian 12+, Fedora 35+, RHEL/Rocky 9+)
eng-drawing-viewer-2.3.1-source.zip	The complete source code of this version, with build instructions
eng-drawing-viewer-2.3.1-linux-source.zip	The complete source code of the Linux edition (the same application code, with the Linux build scripts and the tests it was built with)
eng-drawing-viewer-2.3.1-windows-source.zip	The complete source code of the Windows edition (the same application code, with the Windows build scripts and the tests it was built with)
SHA256SUMS.txt	Checksums of every file
THIRD_PARTY_SOURCES.txt	Where the source of every copyleft component is published, with checksums
THIRD_PARTY_NOTICES.txt, THIRD_PARTY_NOTICES-Windows-x64.txt, THIRD_PARTY_NOTICES-Linux-x86_64.txt	The licence notices of every bundled component (the same files as inside each app)
ENG-Drawing-Viewer-Windows-x64.cdx.json and ENG-Drawing-Viewer-Linux-x86_64.cdx.json	Software bills of materials
Upstream source archives	The unmodified source code of pillow-heif, libheif, libde265, x265 and OpenCV

Other editions. A Universal Mac edition for Intel and Apple silicon is coming soon. The Apple silicon download does not run on Intel Macs.

Install and first launch

1. Open the DMG and drag ENG Drawing Viewer onto Applications.
2. Open the app. It is ad-hoc signed only: it has no Apple Developer ID signature and is not notarized by Apple, so macOS says it could not verify the app. Click Done.
3. Open System Settings › Privacy & Security, scroll down, click Open Anyway next to the message about ENG Drawing Viewer, and confirm with your password or Touch ID.

You do this once. You do not need to turn off Gatekeeper or any other system security setting.

Windows

1. Download ENG-Drawing-Viewer-Windows-x64.zip, right-click it › Extract All, open the folder and run ENG Drawing Viewer.exe. No installation or administrator rights are needed.
2. The app is not code-signed, so SmartScreen may say "Windows protected your PC": click More info › Run anyway.

Linux

chmod +x ENG-Drawing-Viewer-Linux-x86_64.AppImage
./ENG-Drawing-Viewer-Linux-x86_64.AppImage

Without FUSE (fusermount3), run it with --appimage-extract-and-run. Help › Add to Applications Menu creates a menu entry. The file is not signed; check its SHA-256.

Check your download:

shasum -a 256 -c SHA256SUMS.txt --ignore-missing   # macOS
sha256sum -c SHA256SUMS.txt --ignore-missing       # Linux

On Windows: Get-FileHash ENG-Drawing-Viewer-Windows-x64.zip -Algorithm SHA256 in PowerShell.

What's new in 2.3.1

• Image layers and compositing: drop, paste or import images as layers; stack, move, scale and rotate them on the canvas with handles, snapping and numeric fields. Layers keep their original pixels, so repeated transforms never compound blur.
• Clipboard: ⌘C, ⇧⌘C, ⌘X and ⌘V (Ctrl+C, Ctrl+Shift+C, Ctrl+X and Ctrl+V on Windows and Linux) copy, copy merged, cut and paste as a new layer (or a new document); ⌘J and ⇧⌘J make a layer via copy or cut. Copies keep masks, opacity, blend mode and position inside the editor and reach other apps as PNG/TIFF.
• Paint Bucket (G) with tolerance, contiguous and anti-aliasing options, selection limits and fill on a new layer.
• More accurate Magic Eraser: it tells a light subject from a light backdrop better, stops at visible edges and leaves anti-aliased edges. On a synthetic test figure in light clothing on a beige backdrop the match to the true subject improved from 52.7 % to 98–99.8 %; real photographs vary, and a highlight with no visible edge can still leak.
• Improved automatic background removal: edge-aware backdrop seeding and full-resolution edge refinement. It is a helper, not a guarantee: difficult subjects still need touching up with the mask tools.
• Window and toolbar: on macOS the window moves by dragging any empty part of the title bar (Windows and Linux keep their native title bars); dropdown labels and arrows no longer overlap, and the View/Grid/Snap/Rulers bar folds into the View menu when space is short.
• Welcome screen: the app icon no longer touches the "Open a folder of drawings" heading.
• The Read Me on the disk image no longer carries the leftover "private development candidate" line.

Project format. Image projects that contain transformed layers are saved as ENGIMG version 2, which 2.3.0 (and the 2.3.0 Windows and Linux editions) cannot open: they report an unsupported version. Projects without transformed layers are still version 1.

Built and checked

• Built from the published source archive with Python 3.13 and hash-checked dependencies; the dependency set, the minimal OpenCV build and all bundled third-party components are unchanged from 2.3.0. A vulnerability audit of the locked dependencies (pip-audit) found no known vulnerabilities.
• 365 automated tests passed on Apple silicon; the 16 skipped tests are for Windows, Linux or Windows OCR data.
• The packaged app was started on an Apple M3 Max with macOS 27.0.1: it rendered a drawing, ran the PDF tools and the editor checks, left the original file unchanged, and it and its worker processes held 0 network sockets.
• Linux: built from eng-drawing-viewer-2.3.1-linux-source.zip with the same application code as the Apple silicon edition (only test files and build scripts differ). 378 automated tests passed from that archive (14 skipped for other platforms). The AppImage needs glibc 2.34 and GLIBCXX 3.4.29 at most and starts with FUSE, with --appimage-extract-and-run and with no network; it also started on Debian 12, Ubuntu 24.04, Fedora 42 and Rocky Linux 9. It contains a minimal OpenCV built from source (core, imgproc, photo): no FFmpeg, no OpenSSL, no AI model, and the bundle check reports 0 findings apart from one reviewed upstream note.
• Windows: built from eng-drawing-viewer-2.3.1-windows-source.zip with the same application code as the Apple silicon edition (only test files and build scripts differ). The automated tests passed on a Windows Server 2025 runner (392 run, 15 skipped for other platforms), from the checkout and from that archive. The packaged app was run from an unpacked folder and with no network, a scripted session of the real window passed nine interface checks, and a loaded-DLL check found no FFmpeg or OpenSSL. It contains a minimal OpenCV built from source (core, imgproc, photo) and no AI model; the bundle check reports 0 findings apart from one reviewed upstream note.
• The app bundle contains no AI model, no credentials and no personal or machine paths; the bundle check reports 0 findings apart from one reviewed upstream note.
• macOS 14.4 is the highest minimum declared by any bundled binary. This build has been run on macOS 27.0.1 only.
• Optional offline model packs for subject selection are installed by you from local files; none is included.
• Every bundled component and its licence is listed in the app under Help › About › Third-Party Notices.

Known issues

• Universal is not part of this release (see above).
• Windows and Linux have been checked by automated tests and scripted sessions (a CI Windows desktop; an X11 session under Xvfb on Linux, with Wayland not exercised in this release), not yet by a person on an everyday Windows 10/11 PC or a GNOME/KDE desktop. The layer clipboard format between other applications on Windows and Linux is not yet tried by hand. Please report problems in Issues.
• The Linux edition contains NumPy's libquadmath (LGPL-2.1); the nearest upstream GCC source is attached to the 2.3.0 release, see THIRD_PARTY_SOURCES.txt.
• The Windows and Linux source archives come straight from the build and were not made by the usual scanned export; they were scanned separately for personal paths, credentials, employer names and the maintainer's private terms (only upstream false positives).

Changes in detail: CHANGELOG.md

GitHub also attaches "Source code (zip/tar.gz)" archives of this repository automatically; they contain the same source as eng-drawing-viewer-2.3.1-source.zip.

ENG Drawing Viewer 2.3.0

ENG Drawing Viewer 2.3.0 for Macs with Apple silicon, Windows x64 and Linux x86-64. A free, offline workspace for engineering drawings: view folders of PDF drawings and images sharply at any zoom, mark them up with numbered review comments, turn them into PowerPoint slides, edit images, vectors and PDFs, and use 32 PDF tools, all on your own computer.

ENG Drawing Viewer is free software under the GNU Affero General Public License v3 or later.

Download

File	For
ENG-Drawing-Viewer-macOS-Apple-Silicon.dmg	Mac with Apple silicon (M1 or newer), macOS 14.4 or later
ENG-Drawing-Viewer-Windows-x64.zip	Windows 10 (1809) or 11, 64-bit. Portable, no installer
ENG-Drawing-Viewer-Linux-x86_64.AppImage	Linux x86-64 with glibc 2.34 or newer (Ubuntu 22.04+, Debian 12+, Fedora 35+, RHEL/Rocky 9+)
eng-drawing-viewer-2.3.0-source.zip	The complete source code of the Apple silicon edition, with build instructions
eng-drawing-viewer-2.3.0-windows-linux-source.zip	The complete source code of the Windows and Linux editions (build scripts for all editions)
SHA256SUMS.txt	Checksums of every file
THIRD_PARTY_SOURCES.txt	Where the source of every copyleft component is published, with checksums
THIRD_PARTY_NOTICES.txt, THIRD_PARTY_NOTICES-Windows-x64.txt, THIRD_PARTY_NOTICES-Linux-x86_64.txt	The licence notices of every bundled component (the same files as inside each app)
*.cdx.json	Software bills of materials of the Windows and Linux editions
Upstream source archives	The unmodified source code of pillow-heif, libheif, libde265, x265, OpenCV, the AppImage runtime and GCC (libquadmath)

Other editions. A Universal Mac edition for Intel and Apple silicon is coming soon. The Apple silicon download does not run on Intel Macs.

Install and first launch

1. Open the DMG and drag ENG Drawing Viewer onto Applications.
2. Open the app. It is ad-hoc signed only: it has no Apple Developer ID signature and is not notarized by Apple, so macOS says it could not verify the app. Click Done.
3. Open System Settings › Privacy & Security, scroll down, click Open Anyway next to the message about ENG Drawing Viewer, and confirm with your password or Touch ID.

You do this once. You do not need to turn off Gatekeeper or any other system security setting.

Windows

1. Download ENG-Drawing-Viewer-Windows-x64.zip, right-click it › Extract All, open the folder and run ENG Drawing Viewer.exe. No installation or administrator rights are needed.
2. The app is not code-signed, so SmartScreen may say "Windows protected your PC": click More info › Run anyway.

Linux

chmod +x ENG-Drawing-Viewer-Linux-x86_64.AppImage
./ENG-Drawing-Viewer-Linux-x86_64.AppImage

Without FUSE (fusermount3), run it with --appimage-extract-and-run. Help › Add to Applications Menu creates a menu entry. The file is not signed; check its SHA-256.

Check your download:

shasum -a 256 -c SHA256SUMS.txt --ignore-missing   # macOS
sha256sum -c SHA256SUMS.txt --ignore-missing       # Linux

On Windows: Get-FileHash ENG-Drawing-Viewer-Windows-x64.zip -Algorithm SHA256 in PowerShell.

What's in it

• View: folders and nested subfolders of PDFs and images, thumbnails, sheet sizes, natural sorting, sharp tiled rendering from 1.5 % to 4800 %.
• MARK: pen, highlighter, arrow, circle, text, eraser and numbered callouts with linked, spell-checked comments; undo and redo; copy the marked page or save it as a PDF with vector markup. The original PDF is never changed.
• PowerPoint: queue pages and export editable .pptx slides without PowerPoint; marked pages put the drawing on the right and the numbered comments on the left.
• New in 2.3.0: Image Editor, Vector Editor and Edit PDF: layered image editing with background removal and Quick Selection, real SVG/DXF vector editing with raster tracing, and PDF editing with genuine redaction.
• PDF Tools: 32 offline tools to organize, convert, optimize, edit, secure and compare drawings. Office to PDF needs LibreOffice installed.
• Private: no account, no telemetry, no network connections.

Built and checked

• Built from the published source archive with Python 3.13 and hash-checked dependencies. Every ENG Drawing Viewer Python module in the app was compared with that archive and is identical.
• 308 automated tests passed on Apple silicon; the 16 skipped tests are for Windows, Linux or Windows OCR data.
• The packaged app was started on an Apple M3 Max with macOS 27.0.1: it rendered a drawing, ran the PDF tools and the editor checks, left the original file unchanged, and it and its worker processes held 0 network sockets.
• macOS 14.4 is the highest minimum declared by any bundled binary. This build has been run on macOS 27.0.1 only; the 2.2 builds ran on macOS 14.8, 15.7 and 26.6.
• OpenCV is a minimal build from source (core, imgproc, photo), so the app contains no FFmpeg and no OpenSSL.
• Windows and Linux: built from the published Windows/Linux source archive with the same application code (identical to the Apple silicon edition). Windows: 322 automated tests passed (13 skipped for other platforms); Linux: 323 passed (12 skipped). Both packaged apps started, rendered a drawing, ran the PDF tools and the editor checks, left the original unchanged and held 0 network sockets (Windows on Windows Server 2025 with outbound traffic blocked; Linux on Ubuntu 22.04 and 24.04, Debian 12, Fedora 42 and Rocky Linux 9, inside a network namespace without a network). Both contain a minimal OpenCV built from source and no FFmpeg or OpenSSL 1.1.1k.
• No AI model is included. Optional model packs are installed by you from local files.
• Every bundled component and its licence is listed in the app under Help › About › Third-Party Notices.

Known issues

• The Read Me on the disk image still opens with a line left over from testing that calls this a "private development candidate". It is the public 2.3.0 release; the line will go in the next build.
• Windows and Linux have been checked by automated tests and scripted desktop sessions (a CI Windows desktop, Xvfb, headless Wayland), not yet by a person on an everyday Windows 10/11 PC or a GNOME/KDE desktop. Windows has run on Windows Server 2025 only in this round. Please report problems in Issues.
• The Linux edition contains NumPy's libquadmath (LGPL-2.1); the nearest upstream GCC source is attached, see THIRD_PARTY_SOURCES.txt.
• The workspaces have been exercised by automated tests and the packaged smoke test, not yet by a person clicking through the packaged app.

Changes in detail: CHANGELOG.md

Smaller than the earlier release candidates: OpenCV is now built with only the parts the app uses on every edition.

GitHub also attaches "Source code (zip/tar.gz)" archives of this repository automatically; they contain the same source as eng-drawing-viewer-2.3.0-source.zip.

ENG Drawing Viewer 2.2.1 for Windows (Preview)

ENG Drawing Viewer 2.2.1 for Windows — Preview. The rebuilt Windows version of the free, offline workspace for engineering drawings: view folders of PDF drawings and images, mark them up with numbered review comments, use 32 offline PDF tools and export PowerPoint slides, on your own PC.

This is a Preview: it has been built and tested automatically on Windows Server 2022 and 2025, but not yet on everyday Windows 10/11 PCs. Please report anything that doesn't look or work right in Issues.

Mac users: the current Mac version is 2.2.0.

Download

File	For
ENG-Drawing-Viewer-2.2.1-Windows-x64-Setup.exe	Windows 10 or 11, 64-bit. Installs for your user account only (no administrator rights), with a Start menu shortcut and an uninstaller.
ENG-Drawing-Viewer-2.2.1-Windows-x64-Portable.zip	The same app with no installer: unzip it first, then open ENG Drawing Viewer.exe.
eng-drawing-viewer-2.2.1-source.zip	The complete source code of this version, with build instructions.
ENG-Drawing-Viewer-2.2.1-Windows-x64.cdx.json	Software bill of materials.
THIRD_PARTY_SOURCES.txt and the two libiconv archives	Where to get the unmodified source of the copyleft libraries inside the app.
SHA256SUMS.txt	Checksums of every file.

First launch: the app isn't code-signed, so Windows SmartScreen may say it protected your PC. Click More info, check that it's ENG Drawing Viewer, then Run anyway.

Check your download in PowerShell: Get-FileHash .\ENG-Drawing-Viewer-2.2.1-Windows-x64-Setup.exe and compare with SHA256SUMS.txt.

What's in it

• Everything from the Mac app: sharp viewing of PDFs and images, MARK with numbered callouts and linked comments, 32 offline PDF tools, PowerPoint export and queue → PDF.
• Make Searchable (OCR) works out of the box with seven languages.
• Spelling uses Windows' own spell checker, and words you add are remembered.
• Send slides straight into a presentation open in PowerPoint.
• iPhone HEIC photos open once Microsoft's free HEIF and HEVC extensions are installed.
• Windows 11 styling with title bars that follow your light or dark theme; keyboard shortcuts that work with every keyboard layout.
• Open drawings aren't locked, and opening a file while the app runs brings it to the existing window.
• Offline: no account, no telemetry, no network connections.

Built and checked

• Built from the published source archive; two builds are byte-for-byte identical.
• On Windows Server 2022 and 2025: 137 tests pass; the packaged app runs with no Python installed and outbound traffic blocked, opens no network connections, and loads only its own DLLs and Windows' own; the installer installs and uninstalls cleanly.

ENG Drawing Viewer is free software under the GNU Affero General Public License v3 or later. Help › About lists every bundled component and its licence.

ENG Drawing Viewer 2.2.0

The first public release of ENG Drawing Viewer: a free, offline workspace for engineering drawings on the Mac. View folders of PDF drawings and images sharply at any zoom, mark them up with numbered review comments, convert them with 32 PDF tools and turn them into PowerPoint slides, all on your own computer.

ENG Drawing Viewer is free software under the GNU Affero General Public License v3 or later.

Download

File	For
ENG-Drawing-Viewer-2.2.0-macOS-AppleSilicon.dmg	Mac with Apple silicon (M1 or newer), macOS 14.4 or later. Open it and drag the app to Applications.
ENG-Drawing-Viewer-2.2.0-macOS-AppleSilicon.zip	The same app as a ZIP.
eng-drawing-viewer-2.2.0-source.zip	The complete source code of this version, with build instructions.
SHA256SUMS.txt	Checksums of every file.
Upstream source archives	The unmodified source code of the copyleft libraries inside the app (Qt, Qt for Python, MuPDF, PyMuPDF, lxml and GNU libiconv, PyInstaller).

A Windows version is being rebuilt and will follow.

First launch: the app is free software from an independent developer and is not notarized by Apple. The first time you open it, macOS says it could not verify the app: click Done, open System Settings › Privacy & Security, click Open Anyway next to the message about ENG Drawing Viewer, and confirm. You only do this once.

Check your download:

shasum -a 256 -c SHA256SUMS.txt --ignore-missing

What's in it

• View: folders and nested subfolders of PDFs and images, thumbnails, sheet sizes, natural sorting, sharp tiled rendering from 1.5 % to 4800 %.
• MARK: pen, highlighter, arrow, circle, text, eraser and numbered callouts with linked, spell-checked comments; undo and redo; copy the marked page or save it as a PDF with vector markup. The original PDF is never changed.
• PowerPoint: queue pages and export editable .pptx slides without PowerPoint; marked pages put the drawing on the right and the numbered comments on the left.
• PDF Tools: 32 offline tools to organize, convert, optimize, edit, secure and compare drawings. Office to PDF needs LibreOffice installed.
• Scan with iPhone: Continuity Camera scans arrive as PDFs.
• Private: no account, no telemetry, no network connections.

Built and checked

• Built from the published source archive with Python 3.13 and hash-checked dependencies; two independent builds produce byte-identical apps.
• Tested on macOS 14, 15, 26 and 27 (Apple silicon) with no network activity.
• Every bundled component and its licence is listed in the app under Help › About › Third-Party Notices.

Changes in detail: CHANGELOG.md

GitHub also attaches "Source code (zip/tar.gz)" archives of this repository automatically; they contain the same source as eng-drawing-viewer-2.2.0-source.zip.