CRW to G4 Converter

Free CRW to G4 converter — process images online

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Private & Secure

Your data stays protected — CRW files are erased as soon as conversion finishes, and any G4 output is permanently removed within 24 hours.

Simple Interface

The conversion interface is clean and intuitive — just three steps from CRW upload to G4 download. No learning curve, no complicated menus.

Sharp Results

The converter retains maximum visual fidelity during CRW to G4 conversion — your photos maintain their sharpness, color accuracy, and detail.

How to convert CRW to G4

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose g4 or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your g4 file right afterwards

About formats

CRW is Canon's first-generation RAW image format, based on the Camera Image File Format (CIFF) specification developed jointly by Canon, Kodak, and other imaging companies in the late 1990s. Used by Canon's consumer and prosumer cameras from approximately 1998 through the early 2000s — including the PowerShot G-series, EOS D30, EOS D60, and EOS 10D — CRW files store the unprocessed 12-bit sensor readout in a heap-based container structure that differs fundamentally from the TIFF-derived approach used by most other camera manufacturers. The CIFF container organizes data into a hierarchical directory of heap entries, each identified by type and tag, containing the raw image data, JPEG thumbnail, EXIF information, and Canon's proprietary metadata including White Balance tables and Picture Style parameters. CRW was eventually replaced by the CR2 format starting with the EOS-1D Mark II in 2004, as Canon moved to a TIFF-based container that aligned more closely with industry conventions and supported higher bit depths. One advantage of CRW files is historical completeness: they preserve the full original sensor data from an important transitional period in digital photography, and the 12-bit captures from cameras like the EOS D30 still produce excellent results when reprocessed with modern RAW converters. Broad legacy support is another strength — despite its age, CRW remains readable by Adobe Lightroom, Photoshop, RawTherapee, and other modern converters, ensuring these early digital negatives remain accessible.
Developer: Canon
Initial release: 1998
G4 is a monochrome image format based on the ITU-T Group 4 facsimile coding standard (Recommendation T.6), ratified by the CCITT in 1984 as an improvement over Group 3 for use on error-free digital networks like ISDN rather than analog telephone lines. G4 files contain 1-bit image data compressed using exclusively two-dimensional Modified Modified READ (MMR) coding, where each scanline is encoded as a set of differences (changing elements) relative to the line above it. By eliminating the one-dimensional coding fallback and the end-of-line synchronization markers required by Group 3, G4 achieves 20-50% better compression ratios on typical document pages while producing a simpler, more regular bitstream. The format is most commonly encountered as a compression method within TIFF files (TIFF compression tag 4), where it became the standard archival format for scanned documents in enterprise document management, government records, and legal imaging systems. G4 compression is specified at 200, 300, or 400 dpi depending on the scanning application, with 300 dpi being the most common for archival-quality document imaging. One advantage is exceptional compression efficiency for document content: G4's two-dimensional prediction exploits the strong vertical correlation in text and line art pages, typically compressing a 300 dpi letter-size page to 30-50 KB — roughly half the size of equivalent Group 3 encoding. The format's entrenchment in document management infrastructure is another strength — G4 TIFF is the mandated format for many government digital records systems, court filing systems, and corporate archives, supported by every enterprise imaging platform.
Developer: ITU-T (CCITT)
Initial release: 1984

Frequently Asked Questions

What are the reasons to convert CRW to G4?

CRW captures Canon's original RAW data in an aging format — transformation to G4 migrates your classic digital photos into a modern, widely supported standard.

How do I open a G4 file?

G4 works with IrfanView, XnView, fax processing software, and document scanners.

How fast is the CRW to G4 conversion?

Conversion typically takes just a few seconds — CRW images are processed on powerful servers and the G4 output is ready almost immediately.

Is CRW to G4 conversion free?

The converter is free for everyday use. Convertio offers premium plans when you need extended limits or priority processing for CRW to G4.

Does the converter work on all devices?

It works everywhere — any modern web browser on desktop or mobile can handle CRW to G4 conversion through Convertio without installing anything.