| layout | default-layout |
|---|---|
| title | Enable Scale Up for Barcode Recognition - Dynamsoft Barcode Reader How-to Guides |
| description | This page shows how to enable scale up for barcode recognition. |
| keywords | scale up, small image decode, ScaleUpModes, how-to guides |
| needAutoGenerateSidebar | false |
| permalink | /introduction/how-to-guide/enable-scale-up-for-barcode-recognition.html |
For some barcodes with small module size, Dynamsoft Barcode Reader SDK will automatically enlarge the barcode to a proper size before recognition.
Since version 7.3, Dynamsoft Barcode Reader SDK provides [PublicRuntimeSettings]({{ site.structs }}PublicRuntimeSettings.html)->[ScaleUpModes]({{ site.structs }}PublicRuntimeSettings.html#scaleupmodes) with arguments - ModuleSizeThreshold, AcuteAngleWithXThreshold and TargetModuleSize APIs which allow you to set the custom rules for scaling up. To enable it, you need to set [PublicRuntimeSettings]({{ site.structs }}PublicRuntimeSettings.html)->[ScaleUpModes]({{ site.structs }}PublicRuntimeSettings.html#scaleupmodes) to SUM_LINEAR_INTERPOLATION or SUM_NEAREST_NEIGHBOUR_INTERPOLATION, then set the rest parameters.
If the module size of the barcode < ModuleSizeThreshold and the acute angle with X of the barcode > AcuteAngleWithXThreshold, the barcode will be enlarged to N times (N=1,2,3...) till N * modulesize >= TargetModuleSize.
Example
Condition: ModuleSizeThreshold = 4, AcuteAngleWithXThreshold = 30, TargetModuleSize = 4
Result:
The module size of the barcode in the image is 2, which is smaller than ModuleSizeThreshold, and the acute angle is larger than AcuteAngleWithXThreshold, so our library will perform scaling up operation. After scaling up, the barcode is enlarged to 2 times since 2 * modulesize >= TargetModuleSize.
For more information about enabling scale up mode, please see [ScaleUpModes]({{ site.parameters_reference }}scale-up-modes.html#scaleupmodes) and [How to Set Scale Up Modes]({{ site.scenario_settings }}how-to-set-scaleup-modes.html).