PDF Importer for the CE.SDK
Overview
The PDF Importer for the CE.SDK allows you to seamlessly integrate PDF files into the editor while retaining essential design attributes.
Here's an overview of the main features:
- File Format Translation: The importer converts PDF files into the CE.SDK scene file format using
pdfjs-dist (Mozilla's pdf.js), in its legacy/CJS-safe build.
- Bulk Importing: The codebase is adaptable for bulk importing, streamlining large-scale projects.
- Color Translation: RGB, CMYK, and Separation spot colors from PDFs are translated into CE.SDK's native
RGBAColor, CMYKColor, and SpotColor variants. CMYK values are preserved end-to-end instead of collapsed to sRGB; Separation inks are registered on the document's spot-color registry (via engine.editor.setSpotColorCMYK) with their declared alternate CMYK values. DeviceN inks degrade to their alternate-space solid for now.
The following PDF design elements will be preserved by the import:
- Positioning and Rotation: Elements' positioning and rotation are accurately transferred.
- Image Elements: Embedded images (JPEG, PNG) are extracted and placed as graphic blocks. Note that only images with formats that are supported by CE.SDK will be rendered.
- Text Elements: Font family continuity is maintained, with options to supply font URIs or use Google fonts. Bold, italic, and weight styles are supported.
- Vector Paths: SVG path data from the PDF is imported as vector path blocks.
- Colors and Gradients: Solid colors, linear gradients, and radial gradients are faithfully reproduced.
- Spot Color Detection: Cut/fold marks using spot colors (CutContour, Thru-cut, etc.) are detected and can be handled separately. Brand spot inks (Separation / DeviceN entries in the page's
/ColorSpace resource dictionary) are preserved as SpotColor fills and registered on the CE.SDK document-level spot registry.
How It Works
The importer runs a three-stage pipeline on each PDF page:
- Extract — a
pdfjs-dist operator walker emits drawable blocks (images, vector paths, text outlines) in paint order. page.getTextContent() produces one editable text run per line.
- Post-process — adjacent text runs with the same font/size and horizontal overlap are merged into multi-line paragraph blocks.
- Emit — the intermediate representation is written as CE.SDK blocks: text, image, vector, outline.
parse() creates a scene in inches (1pt = 1/72 inch). loadAsBlocks({ units: 'scene' }) uses the active scene's design units, DPI, and font-size unit; without an active scene, it uses inch geometry and point font sizes. Omitting units selects the deprecated 'legacy' mode, which retains inch geometry and passes PDF font-size values unchanged to the engine for compatibility. Embedded images become buffer:// URIs; engine-provided fonts use bundle:// URIs.
Installation
You can install @imgly/pdf-importer via npm or yarn. Use the following commands to install the package:
npm install @imgly/pdf-importer
yarn add @imgly/pdf-importer
Browser Quick-Start Example
import CreativeEngine from '@cesdk/engine';
import { PDFParser, addGfontsAssetLibrary } from '@imgly/pdf-importer';
const blob = await fetch('https://example.com/document.pdf').then((res) =>
res.blob()
);
const engine = await CreativeEngine.init({
license: 'YOUR_LICENSE'
});
await addGfontsAssetLibrary(engine);
const parser = await PDFParser.fromFile(engine, blob);
await parser.parse();
const image = await engine.block.export(
engine.block.findByType('//ly.img.ubq/page')[0],
'image/png'
);
const sceneExportUrl = window.URL.createObjectURL(image);
console.log('The imported PDF file looks like:', sceneExportUrl);
Importing into an Existing Scene
loadAsBlocks() returns detached groups, one per non-empty PDF page, without
replacing the active scene or changing its design units, DPI, or font-size unit.
Create the destination scene before importing and pass units: 'scene' to
convert geometry and text sizes to that scene's units while retaining their
physical size. Attach a returned group before scaling:
const parser = await PDFParser.fromFile(engine, blob);
const { blocks, logger } = await parser.loadAsBlocks({
units: 'scene',
pageIndex: 0,
signal: abortController.signal,
maxBlocks: 10000
});
for (const group of blocks) {
engine.block.appendChild(page, group);
engine.block.scale(group, 0.5);
}
signal cancels preparation and emission. maxBlocks limits allocations,
including temporary blocks, shapes, fills, and duplicated descendants. Failed
imports clean up their own blocks and buffers. Changing the active scene or its
units during emission rejects the import. Temporary pages join the scene only
for synchronous layout and clipping operations and are removed before any await.
loadAsBlocks() also returns an idempotent dispose() callback. Call it if you
discard prepared artwork before committing it to your document's undo history.
It destroys the imported groups and releases their unused buffers and spot-color
definitions, while preserving resources referenced by other blocks.
By default, group bounds follow the imported artwork after layout. To preserve
the original PDF page whitespace and content origin, pass
preservePageBounds: true to loadAsBlocks(). Each group then retains a
transparent, non-selectable child marked with metadata
ly.img.pdf-importer.pageBounds=true. Keep this child to preserve page whitespace
during layout, scaling, and serialization. Groups do not clip overflowing
content. Empty pages return no group.
Existing spot-color definitions remain unchanged; a conflicting PDF definition
produces a SPOT_COLOR_DEFINITION_PRESERVED warning.
Selecting Units
The optional units option accepts 'legacy' or 'scene'. Omitting it is the
same as passing units: 'legacy', so existing calls keep their inch geometry
and pass PDF font-size values unchanged to the engine, regardless of the active
scene's units. For example, a PDF font size of 12 is still passed as 12 when the
scene uses pixel font units. This legacy mode is deprecated; loadAsBlocks()
itself remains supported. Keep any unit conversions your integration already
uses until you explicitly select scene units.
To opt into automatic unit conversion, create the destination scene and pass
units: 'scene'. Then remove the corresponding manual conversions from inches
or font points. Both modes accept the same other options and return
{ blocks, logger, dispose }. Cancellation, allocation limits, disposal, and
preservePageBounds are available in both modes. Neither mode changes the
scene's unit settings.
Both modes return detached groups, not page blocks, and omit empty PDF pages.
If you need to track source page numbers, use getPageCount() and import each
page with loadAsBlocks({ units: 'scene', pageIndex }), handling an empty
blocks array.
Saving Scenes with Stable URLs
By default, the PDF importer creates internal buffer:// URLs for embedded images. These are transient resources that work well when saving to an archive (engine.scene.saveToArchive()), which bundles all assets together.
However, if you want to save scenes as JSON strings (engine.scene.saveToString()) with stable, permanent URLs (e.g., for storing in a database or referencing CDN-hosted assets), you need to relocate the transient resources first.
Why Relocate?
- Scene Archives (
saveToArchive): Include all assets in a single ZIP file. Transient buffer:// URLs work fine.
- Scene Strings (
saveToString): Only contain references to assets. Transient URLs won't work when reloading the scene later. You need permanent URLs (e.g., https://).
How to Relocate Transient Resources
After parsing the PDF file, use CE.SDK's native APIs to find and relocate all transient resources:
const parser = await PDFParser.fromFile(engine, blob);
await parser.parse();
const transientResources = engine.editor.findAllTransientResources();
for (const resource of transientResources) {
const { URL: bufferUri, size } = resource;
const data = engine.editor.getBufferData(bufferUri, 0, size);
const permanentUrl = await uploadToBackend(data);
engine.editor.relocateResource(bufferUri, permanentUrl);
}
const sceneString = await engine.scene.saveToString();
Note on Font URLs
When using addGfontsAssetLibrary() (the default font resolver), the resulting scene string will contain Google CDN URLs for fonts. If you need fonts hosted on your own infrastructure, configure a custom font resolver instead of using the default Google Fonts integration.
Font Strategies
The importer ships with three font-handling presets that trade editability against visual fidelity. Pick one via PDFParser.fromFile(engine, blob, { fontStrategy }), or compose your own with createFontStrategy / createFontCascade.
editableFirstStrategy (default) | perfect-match → PDF-embedded subset bytes → any-match substitution | General-purpose import. Prefers asset-library typefaces for editability, falls back to the PDF's embedded subset for fidelity, substitutes when neither is available. |
exactFidelityStrategy | perfect-match → PDF-embedded subset bytes | Print finalization. Never substitutes; falls through to vector outline when no matching typeface or embedded font is available. |
assetLibraryStrategy | perfect-match → any-match substitution | Brand-locked tools. Skips the embedded-subset stage so only asset-library typefaces are used; non-matching fonts go through substitution or vector outline. |
import { PDFParser, exactFidelityStrategy } from '@imgly/pdf-importer';
const parser = await PDFParser.fromFile(engine, blob, {
fontStrategy: exactFidelityStrategy
});
await parser.parse();
NodeJS Quick-Start Example
Prerequisite — emoji handling. Two CE.SDK settings need attention when
running the importer headlessly under @cesdk/node:
ubq://forceSystemEmojis = false — by default the engine routes any
codepoint that ICU classifies as RGI_Emoji (e.g. ♥, ★, the dingbats
block) through the emoji font even when the active typeface has a glyph
for it. Customer PDFs frequently embed real text fonts (ZapfDingbats,
Webdings, …) that map these codepoints to actual glyphs; forcing the
substitution discards the producer's intended glyph and pulls in a
generic color emoji. Setting the flag to false makes the engine respect
the embedded/substituted font when it covers the codepoint.
ubq://defaultEmojiFontFileUri = <CDN URL> — @cesdk/node ships
only assets/core/, not assets/emoji/NotoColorEmoji.ttf. Even with
forceSystemEmojis=false, true color emoji (🧐, 🎉, …) that no embedded
text font covers still need a working emoji font URI, or
engine.block.export(page, "image/png") aborts with FILE_FETCH_FAILED
for the engine's synthesised local-file URL. Point the engine at the
IMG.LY-hosted preset, or self-host the file and supply your own URI /
bundle:// path.
engine.editor.setSettingBool('ubq://forceSystemEmojis', false);
engine.editor.setSettingString(
'ubq://defaultEmojiFontFileUri',
'https://cdn.img.ly/assets/v4/emoji/NotoColorEmoji.ttf'
);
See the CE.SDK Emojis guide
for the full set of options. Browser consumers initialised with the
default IMG.LY-CDN baseURL already get the emoji font for free, and most
integrations also want forceSystemEmojis=false for the same
embedded-font-respect reason.
import CreativeEngine from '@cesdk/node';
import { promises as fs } from 'fs';
import { PDFParser, addGfontsAssetLibrary } from '@imgly/pdf-importer';
async function main() {
const engine = await CreativeEngine.init({
license: 'YOUR_LICENSE'
});
engine.editor.setSettingBool('ubq://forceSystemEmojis', false);
engine.editor.setSettingString(
'ubq://defaultEmojiFontFileUri',
'https://cdn.img.ly/assets/v4/emoji/NotoColorEmoji.ttf'
);
await addGfontsAssetLibrary(engine);
const pdfBuffer = await fs.readFile('./document.pdf');
const parser = await PDFParser.fromFile(engine, pdfBuffer.buffer);
await parser.parse();
const image = await engine.block.export(
engine.block.findByType('//ly.img.ubq/page')[0],
'image/png'
);
const imageBuffer = await image.arrayBuffer();
await fs.writeFile('./example.png', Buffer.from(imageBuffer));
engine.dispose();
}
main();
Issues
If you encounter any issues or have questions, please don't hesitate to contact us at support@img.ly.
Limitations and Unsupported Features
The PDF importer has some limitations and unsupported features that you should be aware of:
-
Linked Images
- Only embedded images are supported. External image references are not resolved.
-
Font Support
- Fonts not available as a typeface asset source fall back through the configured
fontStrategy (see Font Strategies above): embedded subset bytes when present, then resolver substitution, then a vector-outline rendering. The default strategy substitutes; configure exactFidelityStrategy to disable substitution.
-
Complex Vector Paths
- Some complex clipping paths or compound shapes may experience minor distortion.
-
Annotations and Forms
- PDF annotations, form fields, and interactive elements are not imported.
-
Transparency Groups
- Advanced transparency group blending modes may not be fully reproduced.
-
Image SMask Compositing
- Per-pixel soft masks (image-modulated luminosity SMasks) are supported and composited into the image as an RGBA PNG. As a consequence, JPEG images carrying an SMask lose the JPEG pass-through optimization — they are decoded and re-encoded as PNG, which increases file size.
Changelog
See CHANGELOG.md for release notes.
License
Use of this package is subject to LICENSE.md.