Reading / Writing

Scrimage supports loading and saving of images in the common web formats (png, jpeg, gif, tiff, webp). In addition, it extends javas image.io support by giving you an easy way to set options on the output format when saving.

Warning

The TIFF support via javax.imageio has issues with some tiff images. If this happens, try using the scrimage-formats-extra module which provides extra TIFF support via the TwelveMonkeys library.

Reading

To load an image we use the ImmutableImageLoader interface. An instance can be created via ImmutableImage.loader().

This allows us to customize loading behavior and specify the input source. Supported sources are input streams, byte arrays, files, paths, classpath resources or anything that implements the ImageSource interface.

For example, to load an image from the filesystem:

Java

ImmutableImage image = ImmutableImage.loader().fromFile(file);

Kotlin

val image = ImmutableImage.loader().fromFile(file)

Scala

val image = ImmutableImage.loader().fromFile(file)

or to load from a byte array:

Java

ImmutableImage image = ImmutableImage.loader().fromBytes(bytes);

Kotlin

val image = ImmutableImage.loader().fromBytes(bytes)

Scala

val image = ImmutableImage.loader().fromBytes(bytes)

We can load from byte arrays, streams, files, paths, resources and so on.

Image loader options

The ImmutableImageLoader has several options to customize loading.

Option	Description
detectOrientation	If set to true (the default) then if the image has metadata that indeeds its orientation, then scrimage will rotate the image back to landscape
detectMetadata	If set to true (the default) then scrimage will attempt to parse the metadata tags (if any) present in the file
type	Sets the BufferedImage type that the loaded image should use. If unspecified then the default of the reader implementation is used
sourceRegion	Sets an area to load from the image. If you are loading an image to immediately crop, then this operation can result in less bytes being read from the source

Writing

To save a method, Scrimage requires an ImageWriter for the format you wish to persist to. Scrimage does not use the file extension as a way to infer the format.

Then you can use output or bytes to either write to a file or a byte array respectively.

For example, to save an image as a PNG to a file:

Java

ImmutableImage image = ... // some image
// write out to a file
image.output(PngWriter.Default, new File("/home/sam/spaghetti.png"));

Kotlin

val image = ... // some image
// write out to a file
image.output(PngWriter.Default, File("/home/sam/spaghetti.png"))

Scala

val image = ... // some image
// write out to a file
image.output(PngWriter.Default, new File("/home/sam/spaghetti.png"))

If you want to override the configuration for a writer then you can do this when you create the writer. For example to save a JPEG with 50% compression:

Java

JpegWriter writer = new JpegWriter().withCompression(50).withProgressive(true);
image.output(writer, new File("/home/sam/spaghetti.png"));

Kotlin

val writer = JpegWriter().withCompression(50).withProgressive(true)
image.output(writer, File("/home/sam/spaghetti.png"))

Scala

val writer = new JpegWriter().withCompression(50).withProgressive(true)
image.output(writer, new File("/home/sam/spaghetti.png"))

If you want to override the configuration for a writer then you can do this when you create the writer. For example to save a JPEG with 50% compression as a byte array:

Java

JpegWriter writer = new JpegWriter().withCompression(50).withProgressive(true);
image.bytes(writer);

Kotlin

val writer = JpegWriter().withCompression(50).withProgressive(true)
image.bytes(writer)

Scala

val writer = new JpegWriter().withCompression(50).withProgressive(true)
image.bytes(writer)

Supported Writers

The available writers along with supported options are:

Writer	Option	Description
`JpegWriter`	compression	Set a value between 0 (full lossy compression) and 100 (full quality / no compression)
	progressive	If true then data is compressed in multiple passes of progressively higher detail
`PngWriter`	compression	Set to a value between 0 (no compression) and 9 (max compression). Compression in PNG is lossless
`GifWriter`	progressive	If true then data is compressed in multiple passes of progressively higher detail