SparkScan Session

Defined in library scandit_datacapture_barcode_spark

class SparkScanSession

Added in version 6.20.0

The SparkScan session is responsible for determining the list of relevant barcodes by filtering out duplicates. This filtering of duplicates is completely time-based and does not use any information about the location of the barcode. By default, all the codes scanned in a frame are always reported. It is possible to filter out codes recently scanned by changing SparkScanSettings.codeDuplicateFilter.

When the SparkScan mode is disabled, the session’s duplicate filter is reset.


The SparkScan session should only be accessed from within didScan() or didUpdateSession() and from the thread these methods are called from. It is not safe to be accessed from anywhere else since it may be concurrently modified.

Specifically no reference to newlyRecognizedBarcodes should be kept and traversed outside of didScan() or didUpdateSession(). Instead a copy of the lists should be made to avoid concurrent modification. The individual barcodes can be referenced without copying as they are not further modified.

List<Barcode> get newlyRecognizedBarcodes

Added in version 6.20.0

List of codes that were newly recognized in the last processed frame.

Future<void> reset()

Added in version 6.20.0

Resets the SparkScan session, effectively clearing the history of scanned codes. This affects duplicate filtering: when calling reset() every frame has the same effect as setting the SparkScanSettings.codeDuplicateFilter to 0. This function should only be called inside the listeners’ callback.

int get frameSequenceId

Added in version 6.20.0

The identifier of the current frame sequence.


As long as there is no interruption of frames coming from the camera, the frameSequenceId will stay the same. Note that every time target mode is switched on or off, this number will change.