What is the "Metadata Viewer" extension and how does it work?

This extension allows you to extract metadata from any file type. After installation, it adds an action button to your browser toolbar, which may be hidden in the extension bar. To access it, click on the extension icon and pin the action button to the toolbar area. Click on the icon to open a new inspection window, where you can double-click the interface or drag and drop files to view their metadata. The extension supports multiple file uploads and lists each file and its metadata in the interface. It uses the ExifTool Perl library to extract the metadata, which is widely supported for reading metadata of a vast majority of file formats. Each file's metadata is grouped separately in the interface.

What's new in this version?

Please check the Logs section.

What is ExifTool?

ExifTool is a command-line application and Perl library for reading and writing metadata in many formats, including image, audio, and video formats like JPEG, TIFF, PNG, and PDF. ExifTool supports many different metadata formats, including Exif, IPTC, XMP, JFIF, GeoTIFF, ICC Profile, Photoshop IRB, FlashPix, AFCP, and ID3, as well as manufacturer-specific metadata. It is widely used for reading, writing, and editing metadata in digital photographs and other files.

What is the meaning of groups used by this extension to categorize metadata tags?

ExifTool supports many different tag groups depending on the file format. Here is a list of some of the common tag groups:

• Exif - metadata specific to digital photos including camera make, model, and settings
• IPTC - metadata for news and press photography including captions, keywords, and credit information
• XMP - metadata for a wide range of file types including images, documents, and audio files
• JFIF - metadata for JPEG images
• GeoTIFF - metadata for geographic information
• ICC Profile - metadata for color profile information
• Photoshop IRB - metadata for Adobe Photoshop image editing software
• FlashPix - metadata for FlashPix image files
• AFCP - metadata for AVCHD video files
• ID3 - metadata for mp3 audio files

What does the "read-only" column in the viewer's interface indicate?

Some tags may be marked as "not writable" or "not deletable" in ExifTool because they are considered critical to the file format and the software that uses the file. For example, certain Exif tags, such as the date the photo was taken, are considered important and should not be altered. Additionally, some tags may be protected by the file format or by the software used to create or edit the file, and cannot be modified without potentially causing errors or corrupting the file. Other tags may be protected by the copyright holder or may be used by the operating system or other software and should not be modified.

How does the extension execute ExifTool's code in the browser?

The extension utilizes WebPerl to execute ExifTool's Perl code within the browser by translating Perl's source code to JavaScript using Emscripten. It stores the information in the browser's memory and only needs to provide the library with a small portion of the file, typically the headers, for most file formats.