Convert X3F to DJVU
Max file size 100mb.
X3F vs DJVU Format Comparison
| Aspect | X3F (Source Format) | DJVU (Target Format) |
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| Format Overview | X3F Sigma/Foveon RAW Sigma's proprietary RAW format for cameras with Foveon X3 direct image sensors that capture full RGB color at every pixel location using three vertically-stacked silicon layers, producing uniquely sharp color rendition without a color filter array. Lossless RAW | DJVU DjVu Document Format AT&T Labs' wavelet-compressed document format using IW44 compression for extreme compression of images and documents with intelligent foreground/background separation. Lossy Standard |
| Technical Specifications | Color Depth: 12/14-bit per layer (3 layers) Compression: Lossless or lossy compressed Transparency: Not supported Sensor: Foveon X3 (stacked RGB layers) Extensions: .x3f | Color Depth: 24-bit RGB Compression: IW44 wavelet + JB2 text Transparency: Mask layer Multi-page: Bundled documents Extensions: .djvu, .djv |
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| Processing & Tools | X3F requires Sigma Photo Pro or specialized RAW software for Foveon processing.
# Sigma Photo Pro (official)
# rawpy/dcraw (limited Foveon support)
import rawpy
raw = rawpy.imread('photo.x3f')
rgb = raw.postprocess() | DJVU encoding via wavelet compression. c44 input.ppm output.djvu -slice 74 djvm -c portfolio.djvu p1.djvu p2.djvu |
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| Version History | Introduced: 2002 (Sigma SD9) Current Version: X3F (Quattro, 2014) Status: Active but transitioning to DNG Evolution: X3F (SD9) → Merrill (2012) → Quattro (2014) → DNG (fp, 2019) | Introduced: 1996 (AT&T Labs) Current Version: DjVu 3 (2001) Status: Stable, open-source Evolution: DjVu 1 → DjVu 2 → DjVu 3 (2001) |
| Software Support | Image Editors: Sigma Photo Pro (official), Iridient (Mac) Web Browsers: Not supported OS Preview: Not supported Mobile: Not supported CLI Tools: dcraw (limited), rawpy (limited) | Viewers: DjView, WinDjView, Evince, Okular Web Browsers: Via plugin or JS viewer OS Preview: Linux native, others third-party Mobile: EBookDroid, DjVu Reader CLI Tools: DjVuLibre (c44, djvm) |
Why Convert X3F to DJVU?
X3F files from Sigma's Foveon sensor cameras have notoriously limited software support outside of Sigma Photo Pro. Converting to DJVU creates universally viewable copies of these unique photographs, ensuring access without the specialized software that Foveon RAW data requires.
The Foveon sensor's three-layer RGB capture produces photographs with distinctive sharpness and color accuracy. While DJVU's lossy compression reduces this pixel-level precision, the visual character of Foveon images is well preserved for portfolio presentation and reference viewing.
As Sigma transitions newer cameras to DNG format, X3F represents a legacy format whose dedicated processing software may eventually be discontinued. DJVU conversion creates future-proof viewable archives of this unique sensor technology's output.
Foveon enthusiasts who have built significant X3F collections over years of shooting can compile their best work into compact DJVU portfolios for sharing within the photography community.
Key Benefits of Converting X3F to DJVU:
- Universal Viewing: Access Foveon photos without Sigma software
- Legacy Preservation: Future-proof X3F archives
- Portfolio Creation: Compile Foveon work into browsable documents
- Extreme Compression: 95%+ reduction from RAW data
- Community Sharing: Share Foveon captures as compact files
- Multi-page Bundling: Organize photo series into documents
- Open Tools: Free DJVU viewers on all platforms
Practical Examples
Example 1: Foveon Fine Art Portfolio
Scenario: A Sigma DP Merrill photographer compiles their landscape work into a gallery submission portfolio.
Source: merrill_landscapes_*.x3f (30 images, ~1.5 GB) Target: foveon_landscapes.djvu (30 pages, ~5 MB) Result: Fine art portfolio in 5 MB for gallery review, preserving the distinctive Foveon color rendition.
Example 2: Sigma SD Archive Preservation
Scenario: A photographer preserves their entire Sigma SD1 Merrill collection before potential Sigma Photo Pro discontinuation.
Source: sd1_collection_*.x3f (2,000 files, ~80 GB) Target: sd1_merrill_archive.djvu (2,000 pages, ~140 MB) Result: Complete camera collection in 140 MB viewable document, independent of Sigma Photo Pro software.
Example 3: Street Photography Zine
Scenario: A DP2 Quattro street photographer creates a digital zine from urban captures.
Source: urban_foveon_*.x3f (25 images, DP2 Quattro) Target: urban_foveon_zine.djvu (25 pages, ~4 MB) Result: Digital street photography zine highlighting Foveon's unique rendering, shareable as email attachment.
Frequently Asked Questions (FAQ)
Q: Which Sigma cameras produce X3F files?
A: All Sigma cameras with Foveon sensors that predate the fp: SD9, SD10, SD14, SD15, SD1/SD1 Merrill, DP1/DP2/DP3 Merrill, dp0/dp1/dp2/dp3 Quattro, and sd Quattro/sd Quattro H.
Q: Is Foveon's unique sharpness preserved in DJVU?
A: DJVU's lossy wavelet compression reduces the pixel-level sharpness advantage. The overall visual character is preserved for viewing, but critical detail comparisons should use lossless formats or the original X3F.
Q: Does the converter use Sigma Photo Pro processing?
A: No. The converter uses rawpy/dcraw-based processing. For the best Foveon rendering, process in Sigma Photo Pro first and then convert the output to DJVU.
Q: Will Sigma Photo Pro be discontinued?
A: As of 2026, Sigma Photo Pro remains available but has not been updated for newer operating systems as actively as before. Converting to DJVU provides insurance against potential future incompatibility.
Q: Are Quattro and Merrill X3F files both supported?
A: Yes. Both Merrill (three equal layers) and Quattro (top layer full-res, lower layers 1/4 res) sensor architectures are supported.
Q: How does X3F to DJVU compare to X3F to JPEG?
A: Both produce lossy compressed output. DJVU adds multi-page bundling and document features. JPEG has wider viewer support. For single images, JPEG may be more practical; for collections, DJVU's bundling is advantageous.
Q: Can I recover X3F from DJVU?
A: No. Foveon three-layer sensor data cannot be reconstructed from a compressed two-dimensional image. Keep original X3F files as the authoritative source.
Q: Is batch conversion supported?
A: Yes. Upload multiple X3F files simultaneously for individual conversion. Results can be bundled into multi-page DJVU documents.