Image Export

In addition to exporting scanned documents as PDF, you can also retrieve the pages of the currently scanned document as image files (JPG).

Initialization

Initialize the Docutain SDK for Android as described here.

Export scanned pages as image files

Write images to local files

In order to write the currently scanned pages to local JPG files, you can use the Document.writeImage method. Pass the page you want to export as JPG and the target path where to save it. If you want to export all pages as JPG, you can get the number of pages via Document.pageCount() and loop through all pages like in the follwing example:

Kotlin

//...
//scan a document
//...

val pageCount = Document.pageCount()
for (i in 1..pageCount) {
    val file = File(filesDir, "Image$i.jpg")
    val fileReturn = Document.writeImage(i, file)
}

Java

//...
//scan a document
//...

int pageCount = Document.pageCount();
for (int i = 1; i <= pageCount; i++) {
    File file = new File(getFilesDir(), String.format("Image%d.jpg", i));
    File fileReturn = Document.writeImage(i, file);
}

Get images as Bitmap

Getting the pages as Bitmaps is possible by using the Document.getImage method.

Kotlin

//...
//scan a document
//...

val pageCount = Document.pageCount()
for (i in 1..pageCount) {
    var bitmap = Document.getImage(i)
}

Java

//...
//scan a document
//...

int pageCount = Document.pageCount();
for (int i = 1; i <= pageCount; i++) {
    Bitmap bitmap = Document.getImage(i);
}

tip

You can pass your own Bitmap Options in order to get back a Bitmap that fits your needs.

Kotlin

val options = BitmapFactory.Options()
options.inSampleSize = 2

val pageCount = Document.pageCount()
for (i in 1..pageCount) {
    var bitmap = Document.getImage(i, options)
}

Java

BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 2;

int pageCount = Document.pageCount();
for (int i = 1; i <= pageCount; i++) {
    Bitmap bitmap = Document.getImage(i, options);
}

Get images as ByteArray

You also have the possibility to get the images as ByteArray:

Kotlin

//...
//scan a document
//...

val pageCount = Document.pageCount()
for (i in 1..pageCount) {
    var imageBytes = Document.getImageBytes(i)
}

Java

//...
//scan a document
//...

int pageCount = Document.pageCount();
for (int i = 1; i <= pageCount; i++) {
    byte[] imageBytes = Document.getImageBytes(i);
}

PageSourceType

When getting the images as Bitmap or ByteArray, you can define a PageSourceType.

Kotlin

//...
//scan a document
//...

val pageCount = Document.pageCount()
for (i in 1..pageCount) {
    var bitmap = Document.getImage(i, null, PageSourceType.CUT_FILTER);
}

Java

//...
//scan a document
//...

int pageCount = Document.pageCount();
for (int i = 1; i <= pageCount; i++) {
    Bitmap bitmap = Document.getImage(i, null, Document.PageSourceType.CUT_FILTER);
}

You have the following options:

• PageSourceType.CUT_FILTER This is the default value if you do not provide any. The image will be the cut and filtered image which is the one the user sees when finishing the scan process.

• PageSourceType.CUT_ONLY This will give you the cut but unfiltered image. If you for example use the image for further processing in your own OCR pipeline which uses custom filter operations, this option might improve your OCR results as opposed to PageSourceType.CUT_FILTER. But this is no general rule and highly depends on your pipeline.

• PageSourceType.ORIGINAL This will give you the uncut, unfiltered image as it was provided by the camera.