Some files cause "Offset is outside the bounds" error

[til-schneider]

I recently added exifr to Picturama. It made the photo import 20x faster! Thank you very much for that.

However in my tests I discovered that some images fail to scan with an "Offset is outside the bounds" error. The old lib I used before (exif-parser) was able to scan these images.

Here is an example image: https://github.com/picturama/test-data/raw/master/photos/800/door-knocker.jpg

Test call (tested with exifr 5.0.2):

// Works
await exifr.parse(imagePath)

// Fails
await exifr.parse(imagePath, { xmp: true })

Here is the stack:

Error: Offset is outside the bounds of the DataView RangeError: Offset is outside the bounds of the DataView
      at DataView.getUint16 (<anonymous>)
      at Object.getUint16 (node_modules/exifr/dist/full.umd.js:1:3497)
      at Object._findAppSegments (node_modules/exifr/dist/full.umd.js:1:22124)
      at Object.findAppSegments (node_modules/exifr/dist/full.umd.js:1:21174)
      at Object.parse (node_modules/exifr/dist/full.umd.js:1:20428)
      at ee.parse (node_modules/exifr/dist/full.umd.js:1:12339)
      at Object.te [as parse] (node_modules/exifr/dist/full.umd.js:1:13138)

However when I try this image on your homepage then in works - even with xmp enabled. Are you using an older version of exifr there?

[MikeKovarik]

Hello. Firstly: Glad you use and like it. :)

I quickly looked into it before work and found what causes it.
So exifr by default reads files by chunks. This makes it that fast - quickly gauge if it's worth to keep parsing the file or quit early.

Why website works? Chunk reading is a heuristic. It works on 99% of files. But there's still that 1% (which is malformed or non standard anyway). Exifr doesn't crash in this case. It just may not reach all the metadata. So i disabled chunked reader in the website.

What cause your problem is a bug where the metadata header was split, right around the edge of the loaded chunk.

I will try to release the fix when i get home from work. Or maybe tomorrow since I've done some unfinished and uncommited work that needs to be cleaned first.

For now, you can disable chunk reading with options {chunked: false}

[vip30]

I just starting switch project from iptc library to exifr, it works quite well to be honest.

However, I have couple of images have these problems:

• When I enable iptc, it throws RangeError: Offset is outside the bounds of the DataView
• and another image when enable icc, it throws RangeError: Invalid typed array length: -6

Even in the homepage still got the errors:

Images:
a.jpg
b.jpg

[MikeKovarik]

Hello. Thank you both for the info and problematic files 👍. I just released 5.0.3 which fixes all of your bugs.

[til-schneider]

Thank you very much for the fix. It is included in the new version 1.2.0 of Picturama. 👍