Accuracy Disclaimer

Last updated: May 2026

This page sets out honest expectations for conversion accuracy. Conversions follow the format specifications and use established libraries (per Format Catalog). However, image-format conversions have inherent trade-offs, and some pairs are perfect while others involve quality loss or representational gaps.

1. The four conversion-pair categories

For lossy → lossy, convert from the original lossless source where possible. The two-stage lossy compression compounds quality loss.

2. Per-format honest notes

JPEG

• Quality slider 75–95 by default. Above 95 the file gets much larger with diminishing visual gain. Below 75 visible artefacts (block boundaries, colour banding) appear in flat regions.
• Chroma subsampling 4:2:0 by default (matches most browsers / cameras). 4:4:4 available for use cases where chroma fidelity matters.
• Progressive encoding available for web delivery (faster perceived load).
• EXIF handling: stripped by default on web-export pairs (privacy & size); preservable on opt-in.
• Colour profile (ICC) preserved by default.

PNG

• Lossless; output round-trips perfectly.
• Compression level 6 default (good balance of speed vs file size). Compression level 9 produces slightly smaller files at noticeably slower encoding.
• Bit depth: 8-bit (standard), 16-bit (preserved on input from 16-bit sources like TIFF / RAW where requested).
• Alpha channel preserved.
• Honestly: PNG of a photographic image is much larger than JPEG / WebP / AVIF at similar perceived quality. Use PNG for screenshots, logos, things-with-sharp-edges-or-transparency. Don't use PNG for vacation photos unless you need lossless.

WebP

• Lossy or lossless modes.
• Lossy WebP: ~25–35% smaller than JPEG at similar quality for most content.
• Lossless WebP: typically 25% smaller than PNG.
• Browser support universal since 2020.
• Caveat: very old systems / image viewers may not support WebP. For maximum compatibility, JPEG / PNG are still the safest choices.

AVIF

• Smaller than WebP at same quality (typically 10–25% smaller).
• Encoding is slow — 10–20s for large files is normal, not a bug.
• Browser support: Chrome (since 85, 2020), Firefox (since 93), Safari (since 16.4 / iOS 16.4 in 2023). Older browsers fail to display.
• Right format when you control the destination and want maximum compression.

HEIC / HEIF

• Apple's iPhone default since iOS 11. Smaller than JPEG at same quality.
• Decoded via libheif. Conversion to JPEG / PNG / WebP / AVIF works smoothly.
• Many web platforms still don't render HEIC reliably (older Safari versions on Windows; older WordPress themes; many SaaS tools); converting to JPEG / WebP for upload to those platforms is the standard fix.
• EXIF preserved.

TIFF

• Lossless; print & archival standard.
• Compression options: LZW (lossless), ZIP / Deflate (lossless), JPEG-in-TIFF (lossy).
• Multi-page TIFF: first page extracted by default. Multi-page conversion on request.
• ICC colour profile preserved — important for print workflows.
• Big files. A 20-megapixel uncompressed TIFF is ~60 MB. LZW or ZIP cut that meaningfully without quality loss.

RAW (CR2, NEF, ARW, etc.)

• libraw applies default tone-mapping to render the sensor data into a usable image.
• This is NOT a substitute for proper RAW workflow. For real exposure / colour / lens corrections, use Lightroom, Capture One, darktable, or your camera vendor's RAW software.
• What we provide is convenience: quick previews, format conversion when you don't have the camera vendor's software handy.
• Output sizes are large: a 24-megapixel RAW → 16-bit TIFF is ~140 MB.

Vector formats (SVG, EPS, AI, PSD)

• Vector → raster rasterised at chosen DPI (default 96 for screen, 300 for print). Edge fidelity excellent at output resolution.
• Raster → vector (SVG output from PNG / JPEG): basic edge-trace. Honestly: for production logo work, use Illustrator / Inkscape with a person making decisions about path simplification. Auto-trace is a starting point, not a finished result.
• PSD input flattened to single image — layers and effects baked in. Multi-layer extraction NOT supported; use Photoshop / Photopea / GIMP for that.
• EPS rasterised via Ghostscript at chosen DPI.

3. Colour management

• ICC colour profiles preserved for formats that support them (TIFF, JPEG with ICC, PSD). Important for print workflows and accurate display on wide-gamut monitors.
• sRGB assumed for inputs that don't specify a colour profile (most web images).
• Wide-gamut conversion (Display P3, Adobe RGB) preserved through the conversion when target format supports it.
• Honest caveat: if you do colour-critical work (commercial print, calibrated photography), verify colour fidelity with your normal proofing workflow. We use standard library colour-management; we don't certify colour accuracy for regulated workflows.

4. EXIF and metadata

• Default behaviour on web-export pairs (PNG / JPEG / WebP / AVIF): EXIF stripped, except where preserving aids the conversion (orientation tag respected).
• Why stripped by default: EXIF often contains GPS coordinates, camera serial number, sometimes thumbnail of the original. These are privacy-relevant on photos shared online.
• Opt-in to retain: if you specifically want EXIF preserved, the conversion form has an option for it.
• Default behaviour on archival pairs (TIFF, PSD): EXIF preserved.

5. When to use other tools

• Production print workflows — use Adobe / Capture One / a calibrated workflow with colour proofing.
• Real RAW development — Lightroom / darktable.
• Multi-layer Photoshop work — Photoshop / Photopea / GIMP.
• Production logo / vector work — Illustrator / Inkscape.
• AI-based upscale / enhance / denoise — Topaz, Adobe's tools, Let's Enhance. We don't do those (per AI Policy).
• Sensitive images (passports, medical, financial) — ImageMagick command-line locally; GIMP.
• Bulk batch processing — XnConvert (free), ImageMagick scripts, Cloudinary / ImageKit (commercial).

6. No warranty

Conversion output is provided "as is" and "as available", without warranty for any specific input or fitness for any particular purpose. Per Terms of Service.

7. Reporting accuracy issues

Email info [at] iloveimg [punto] online with subject Conversion accuracy: [pair]. Include sample input (if shareable), expected vs actual output, what reference you used. We use these to drive corrections per Corrections Policy.

Related pages: Format Catalog · Data Handling · Corrections Policy · Disclaimer · Responsible Use