drewnoakes/metadata-extractor-dotnet

UNICODE EXIF UserComment tag read as BigEndian Unicode results in incorrect decoding

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#423 opened on Jun 12, 2024

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Description

338819806-4bc1ebcf-6edb-4545-92e5-ff2fc4f7cfb2

The metadata in the file has a UserComment tag in the Exif SubIFD directory that contains a UNICODE-encoded text containing JSON. With the existing code, the text will be decoded using BigEndianUnicode, which will result in incorrect text.

If the Encoding in TagDescriptor for the UNICODE encodingMap is set to Encoding.Unicode, it will decode properly.

Should this be just Unicode? Is there a discriminator that determines what endianess it should use?

Contributor guide

Research direction
Inspect the encodingMap in ExifUserComment tag descriptor and understand how the endianness is determined. Check if the encoding should be set to Unicode (UTF 16LE) based on Exif byte order or always BigEndianUnicode.
Tech stack
csharp
Domain
backendapi
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Mostly clear
Prerequisites
C#metadata extraction concepts
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75