Backups/TwelveMonkeys
2
0
Fork 0
mirror of https://github.com/haraldk/TwelveMonkeys.git synced 2025-08-04 20:15:28 -04:00
Code Issues Projects Releases Wiki Activity

Add readme section about working with damaged images

Browse Source
This commit is contained in:
Sam Stephens 2024-11-28 15:16:22 +13:00 committed by Harald Kuhr
parent 0cf784ee60
commit 274886b1d9
1 changed files with 35 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
README.md
View File

@ -223,6 +223,41 @@ BufferedImageOp ditherer = new DiffusionDither();
BufferedImage output = ditherer.filter(input, null);
```
#### Working with damaged images
When using the normal patterns for loading images, trying to load a damaged image will result in an Exception being thrown.
```java
BufferedImage image = null;
try {
image = ImageIO.read(file);
} catch (IOException exception) {
// TODO: Optionally handle, log a warning/error etc
}
```
In this scenario, if the image is damaged, and `ImageIO.read` throws an exception, `image` is still null - it's not possible for a function to both return a value and throw an exception.
However, in some cases it may be possible to get usable image data from a damaged image. The way to do this is use an `ImageReadParam` to set a `BufferedImage` as a destination.
```java
ImageReadParam param = reader.getDefaultReadParam();
int width = reader.getWidth(0);
int height = reader.getHeight(0);
BufferedImage image = reader.getRawImageType(0).createBufferedImage(width, height);
param.setDestination(image);
try {
reader.read(0, param);
}
catch (IOException e) {
// TODO: Optionally handle, log a warning/error etc
}
```
In theory this should work for all plugins, but the result is very much plugin/implementation specific. With some formats and some forms of damaged file, you may get an image that is mostly useful.
However you should be prepared for the possibility this just gives a blank or empty image.
## Building
Download the project (using [Git](https://git-scm.com/downloads)):