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Optimizing Performance

By following the previous guide, you managed to create your own barcode reader project. However, you might look to improve the performance of the reader in some areas:

  • Unrecognized barcodes.
  • Slow processing speed.
  • Misread results.

In this article, we will share some solutions to help you solve the above issues.

How to Decode Unrecognized Barcodes

There are several reasons that may cause a barcode to be unrecognized.

Generally speaking

  • The barcode reader failed to locate the barcode.
  • The barcode is located but the result cannot be decoded.

Adjust the DeblurLevel

DeblurLevel is the parameter that controls how much effort the library spends on decoding the localized barcodes. Setting a higher value for DeblurLevel will improve the recognition rate and decrease the recognition speed at the same time. DeblurLevel is set to 9 (the highest level) by default. Therefore, if you find the recognition speed is not satisfying, you can reduce the DeblurLevel to balance the performance.

Value Type Value Range Default Value
int [0,9] 9
PublicRuntimeSettings settings = reader.getRuntimeSettings();
settings.deblurLevel = 9;

Enlarge the resolution

When decoding from the video streaming, it is recommended to set the resolution to 1080P.

// You can use the following method to change the resolution.

Add Localization Modes

The LocalizationModes determines how the library locates the barcode. Using multiple LocalizationModes can help the library to find at least one barcode for further processing. When you find there are barcodes that can’t be recognized, you may try adding extra parameters to the LocalizationModes.

PublicRuntimeSettings settings = reader.getRuntimeSettings();
// You can specify at most 8 localization modes.
// The localization modes will be executed in the order in which they are set.
// If the barcode reader decode enough barcodes via a forward mode, the behind modes will not be executed
// Always put LM_SCAN_DIRECTLY before LM_CONNECTED_BLOCKS and put LM_LINES before LM_STATISTICS. Otherwise, they can't improve the readability.
settings.localizationModes = new int[]{EnumLocalizationMode.LM_SCAN_DIRECTLY,EnumLocalizationMode.LM_CONNECTED_BLOCKS,EnumLocalizationMode.LM_LINES,EnumLocalizationMode.LM_STATISTICS};

How to Improve the Speed

Set ScaleDownThreshold

Images with higher pixel density than the threshold will be scaled down. The default value of ScaleDownThreshold is 2300 (pixel). You can set a smaller value when you need to speed up the recognition.

Value Type Value Range Default Value
int [512,0x7fffffff] 2300
PublicRuntimeSettings settings = reader.getRuntimeSettings();
settings.scaleDownThreshold = 1200;

Reduce Timeout for Video Streaming Barcode Decoding

Timeout, which is measured in milliseconds, determines the maximum time the library will spend on each image. Decreasing the value of Timeout might help you on improving the recognition speed of video decoding. Some low-end devices may not be able to complete the barcode processing if the Timeout is too short. Make sure to test that you are using a suitable Timeout value for low end devices.

Value Type Value Range Default Value
int [0,0x7fffffff] 10000
PublicRuntimeSettings settings = reader.getRuntimeSettings();
settings.timeout = 9;

How to Filter out Misread Results

Increase the Confidence Level

MinResultConfidence is the parameter that controls the result confidence to filter the results below the set confidence. The default value of MinResultConfidence is 30. You can set MinResultConfidence higher to get even more accurate results.

Value Type Value Range Default Value
int [0,100] 30
PublicRuntimeSettings settings = reader.getRuntimeSettings();
settings.minResultConfidence = 40;

Enable Result Verification

Use multiple barcode results from different video frames to verify the correctness of the results. You can enable the result verification to further improve the result accuracy.


Other Settings

If the above settings can not solve the issues you have, feel free to contact us for further technical support. DBR has a lot of built-in parameters for image processing, localization supporting and barcode decoding. Please feedback your problems to us so that our technical support team will help you configure the parameters to match your requirements.

This page is compatible for:

Version 7.5.0

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