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Working with images in Java for the first time and am getting some bizarro exceptions that aren't documented very well. Here's the line of code that is failing:

BufferedImage imgSelected = ImageIO.read(new File("/abs/url/to/file/image.jpg"));

This line is throwing an IIOException with Unsupported image type as the exception message. I have checked and re-checked that it is in fact this line throwing the exception, that the File object is valid, that the URL is valid, and that the image.jpg is in fact a valid JPG that loads perfectly fine in other image viewers.

What could I do to get more information about the nature of this exception? Is this the traditional way for loading images in Java 7, or is this an old/deprecating method? There's just not a lot of info out there about these "Unsupported image type" exceptions, and surely, ImageIO supported JPGs!

Thanks for any help!

IAmYourFaja
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5 Answers5

36

Try to check the encoding of the JPEG. ImageIO can't read CMYK-encoded jpeg images for example. AFAIK, ImageIO hasn't been updated for years, so you'd like to try and use the official alternative/extension: JAI ImageIO.

Unforutnately, JAI ImageIO needs some native libraries installed into the JRE, which might be unwanted. We do the following:

  • use Apache Sanselan to detect, whether it's a JPEG
  • since Sanselan can't read and write JPEG, use the plain old AWT JPEGCodec: JPEGCodec.createJPEGDecoder(...)
  • to convert CMYK to RGB, we then get the raster of the read BufferedImage and manually convert it (you could use ICC profiles, but the manual conversion fits our needs)

Here's a question of mine that resulted of the fact that ImageIO doesn't support all types of JPEG images, and I there stated a little more of my findings of why you get that message: Pure Java alternative to JAI ImageIO for detecting CMYK images

DRCB
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Thomas
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    The catch here of course is that JAI ImageIO's native libraries (at least on Windows) only support 32-bit. – Hakanai Mar 26 '12 at 23:24
12

To work with images in a specific format,you need to add the corresponding dependency, such as imageio-jpeg or imageio-tiff:

<dependency>
<groupId>com.twelvemonkeys.imageio</groupId>
<artifactId>imageio-jpeg</artifactId>
<version>3.3.2</version>
</dependency>

<dependency>
<groupId>com.twelvemonkeys.imageio</groupId>
<artifactId>imageio-bmp</artifactId>
<version>3.3.2</version>
</dependency>

<dependency>
<groupId>com.twelvemonkeys.imageio</groupId>
<artifactId>imageio-core</artifactId>
<version>3.3.2</version>
</dependency>

the built-in ImageIO Java API loads the plugins automatically at runtime.

Mayen
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  • Just tried a Photoshop-jpg-file that I couldn't read with ImageIO (up to now). Twelvemonkeys worked out of the box and I could read the problematic file. Just added dependencies and nothing more (I don't know how Twelvemonkeys does the trick - but it seems to do it well). You don't have to include imageio-core. The dependency to imageio-jpeg is enough (for jpeg-files) and maven does the rest. Twelvemonkey seems to support a lot more file types (see list at https://github.com/haraldk/TwelveMonkeys ). –  Jan 04 '22 at 20:16
  • Works nicely with newer Java versions as well, just by adding the dependency. For gradle users, the artifact may be used with e.g. `implementation 'com.twelvemonkeys.imageio:imageio-jpeg:3.8.2'` for jpg. – mindoverflow Jul 31 '22 at 10:51
11

I've unfortunately come across a lot of standard violating JPEG files. ImageIO is particularly picky and often refuse to load images, which are often loaded and apparently displayed correctly by other software with less strict checks on the file format.

It's not very pretty, but one workaround is to use the Oracle VM internal JPEG decoder directly (com.sun.image.codec.jpeg.JPEGCodec), as it seems to tolerate more spec deviations as the ImageIO wrapper:

BufferedImage img = 
    JPEGCodec.createJPEGDecoder(inputStream).decodeAsBufferedImage();

This is of course not an ideal solution, since using implementation specific classes will lock you to a specific VM vendor and may break with newer VM versions, but if you'll only used the software in a controlled environment, it may be better than no solution at all.

jarnbjo
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  • That's a great suggestion @jarnbjo. Thanks for taking the time to repond to my question, definitely food for thought down the road. – IAmYourFaja Aug 24 '11 at 17:24
  • I've tried it on a cmyk image with caused the exception as in the topic and it failed (java version "1.8.0_60"): com.sun.image.codec.jpeg.ImageFormatException: Not a JPEG file: starts with 0xce 0x08 at sun.awt.image.codec.JPEGImageDecoderImpl.readJPEGStream(Native Method) ~[?:1.8.0_60] – yetanothercoder Oct 13 '15 at 10:33
1

Another option is to use .jar prepared by Werner Randelshofer:

http://www.randelshofer.ch/blog/2011/08/reading-cmyk-jpeg-images-with-java-imageio/ or Monte Media Library: http://www.randelshofer.ch/monte/

It looks quite easy and similar to ImageIO usage and available under CC license.

Ravbaker
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0

This tutorial provided an answer using the apache commons IO library. I found it to be a cleaner implementation. I included the dependency below

<dependency>
  <groupId>commons-io</groupId>
  <artifactId>commons-io</artifactId>
  <version>2.11.0</version>
</dependency>

Here is the code that worked after adding the dependency

    public ResponseEntity<byte[]> getImage(@PathVariable("filename") String filename) {
     byte[] image = new byte[0];
      try {
          image = FileUtils.readFileToByteArray(new File(FILE_PATH_ROOT+filename));
      } catch (IOException e) {
          e.printStackTrace();
      }
      return ResponseEntity.ok().contentType(MediaType.IMAGE_JPEG).body(image);
    }
Ignatius Ojiambo
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