What is MIME type "image/x-canon-cr3"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

image/x-canon-cr3 is the MIME type for Canon’s proprietary RAW image format. It labels files saved as CR3.

The format stores unprocessed sensor data with minimal in-camera adjustments. Such files retain extensive detail and color information. This helps when making precision edits later.

Used in professional and enthusiast photography for advanced editing.
Ensures preservation of a wide dynamic range and rich color details.
Facilitates non-destructive workflows in image processing software.

Applications like Adobe Lightroom and Canon Digital Photo Professional support this type. Its design is tailored for users who need optimal image quality for post-processing.

For a broader overview of raw formats, visit Wikipedia: Raw Image Format.

Associated file extensions

.cr3

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: image/x-canon-cr3

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="image/x-canon-cr3">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');
    
    http.createServer((req, res) => {
      res.setHeader('Content-Type', 'image/x-canon-cr3');
      res.end('Content here');
    }).listen(3000);

Associated file extensions

.cr3

FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.