Unknown data block type

Classification

Validator	Validator version	Error message type
JHOVE	1.32.1

File format	Version	Specification	Description	Location
image/gif	1987a			corpus
image/gif	1989a			corpus

Analyses

Possible solutions

Output example

Validator returned error.
<?xml version="1.0" encoding="UTF-8"?>
<jhove xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schema.openpreservation.org/ois/xml/ns/jhove" xsi:schemaLocation="http://schema.openpreservation.org/ois/xml/ns/jhove https://schema.openpreservation.org/ois/xml/xsd/jhove/1.9/jhove.xsd" name="Jhove" release="1.32.1" date="2025-02-06">
 <date>2025-10-29T17:25:14+02:00</date>
 <repInfo uri="/corpus/file-scraper/tests/data/image_gif/invalid_1987a_truncated.gif">
  <reportingModule release="1.4.3" date="2022-04-22">GIF-hul</reportingModule>
  <lastModified>2025-10-28T08:43:04+02:00</lastModified>
  <size>270</size>
  <format>GIF</format>
  <version>87a</version>
  <status>Not well-formed</status>
  <sigMatch>
  <module>GIF-hul</module>
  </sigMatch>
  <messages>
   <message subMessage="Type = 0" offset="206" severity="error" id="GIF-HUL-2" infoLink="https://github.com/openpreserve/jhove/wiki/GIF-hul-Messages#gif-hul-2">Unknown data block type</message>
  </messages>
  <mimeType>image/gif</mimeType>
  <profiles>
   <profile>GIF 87a</profile>
  </profiles>
 </repInfo>
</jhove>

Notes on the error

Related errors by source files

ImageMagick:    corrupt image
ImageMagick:    negative or zero image size
JHOVE:  Unknown data block type
Pillow: cannot identify image file
Pillow: Image size (.* pixels) exceeds limit of .* pixels, could be decompression bomb DOS attack.

Notice: any operation suggested on this page should be carefully considered before use, as this article is in continuous development.