| layout | title | description | keywords | needAutoGenerateSidebar | needGenerateH3Content | noTitleIndex |
|---|---|---|---|---|---|---|
default-layout |
Read dense barcodes - Dynamsoft Barcode Reader SDK |
This page describes how to read dense barcodes in Dynamsoft Barcode Reader SDK. |
dense barcodes, qrcode, datamatrix |
true |
true |
true |
A QR code can store up to 7,089 numbers, 4,296 alphanumeric characters, 2,953 bytes, or 1,817 Japanese Kanjis. As the encoded information increases, the QR code becomes denser. The diagram below displays a QR code that has high density.
Figure 1 – High-density QR Code
In some scenarios, high-density QR codes become more difficult to locate and recognize due to small barcode images, perspective, and distortion.
We can do the following to optimize the read rate of high-density QR codes:
- Scale up modules if they are too small
- Sharpen the image
- Run gray equalization
The following code snippet shows how to configure the parameters via a json template string.
>- JavaScript >- Android >- Objective-C >- Swift >- Python >- Java >- C# >- C++ >- C > > ```javascript const scanner = await Dynamsoft.DBR.BarcodeScanner.createInstance(); // Allow js to directly process 4K images in canvas without compressing them. // Please test on the target devices. On devices with limited memory, the settings can lead to out of memory. scanner.maxCvsSideLength = 4096; // Defines settings for reading dense barcodes in a template. let jsonString = "{\"ImageParameter\":{\"BarcodeComplementModes\":[\"BCM_SKIP\"],\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[\"LM_CONNECTED_BLOCKS\"],\"ScaleUpModes\":[\"SUM_LINEAR_INTERPOLATION(0,4,6)\"],\"MaxAlgorithmThreadCount\":1,\"Name\":\"high-density-qr-tpl\",\"ScaleDownThreshold\":10000,\"Timeout\":5000},\"Version\":\"3.0\"}"; // Configures the BarcodeScanner object with the settings. await scanner.initRuntimeSettingsWithString(jsonString); scanner.show(); ``` > ```java String jsonPara = "{\"ImageParameter\":{\"BarcodeComplementModes\":[\"BCM_SKIP\"],\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[\"LM_CONNECTED_BLOCKS\"],\"ScaleUpModes\":[\"SUM_LINEAR_INTERPOLATION(0,4,6)\"],\"MaxAlgorithmThreadCount\":1,\"Name\":\"high-density-qr-tpl\",\"ScaleDownThreshold\":10000,\"Timeout\":5000},\"Version\":\"3.0\"}"; // Apply the template string to the reader. reader.initRuntimeSettingsWithString(jsonPara, EnumConflictMode.CM_OVERWRITE); TextResult[] result = reader.decodeFile("YOUR-IMAGE-FILE-PATH"); ``` > ```objc NSError* err = nil; NSString* jsonPara = @"{\"ImageParameter\":{\"BarcodeComplementModes\":[\"BCM_SKIP\"],\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[\"LM_CONNECTED_BLOCKS\"],\"ScaleUpModes\":[\"SUM_LINEAR_INTERPOLATION(0,4,6)\"],\"MaxAlgorithmThreadCount\":1,\"Name\":\"high-density-qr-tpl\",\"ScaleDownThreshold\":10000,\"Timeout\":5000},\"Version\":\"3.0\"}"; // Apply the template string to the reader. [reader initRuntimeSettingsWithString:jsonPara conflictMode:EnumConflictModeOverwrite error:&err]; NSArray* result = [reader decodeFileWithName:"YOUR-IMAGE-FILE-PATH" error:&err]; ``` > ```swift let jsonPara = "{\"ImageParameter\":{\"BarcodeComplementModes\":[\"BCM_SKIP\"],\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[\"LM_CONNECTED_BLOCKS\"],\"ScaleUpModes\":[\"SUM_LINEAR_INTERPOLATION(0,4,6)\"],\"MaxAlgorithmThreadCount\":1,\"Name\":\"high-density-qr-tpl\",\"ScaleDownThreshold\":10000,\"Timeout\":5000},\"Version\":\"3.0\"}" // Apply the template string to the reader. try? reader.initRuntimeSettingsWithString(jsonPara,conflictMode:EnumConflictMode.overwrite) let result = try? reader.decodeFileWithName("YOUR-IMAGE-FILE-PATH") ``` > ```python error = BarcodeReader.init_license("YOUR-LICENSE-KEY") if error[0] != EnumErrorCode.DBR_OK: print(error[1]) dbr = BarcodeReader() dbr.init_runtime_settings_with_string('{"Version":"3.0", "ImageParameter":{"Name":"high-density-qr-tpl","DeblurModes":[{"Mode":"DM_SHARPENING"},{"Mode":"DM_GRAY_EQUALIZATION"}],"ExpectedBarcodesCount":1,"LocalizationModes":[{"Mode":"LM_CONNECTED_BLOCKS"}],"ScaleUpModes": [{"Mode": "SUM_LINEAR_INTERPOLATION","AcuteAngleWithXThreshold": 0,"ModuleSizeThreshold": 4,"TargetModuleSize": 6}],"ScaleDownThreshold":10000,"Timeout":5000}}') text_results = dbr.decode_file("YOUR-IMAGE-FILE-PATH") # Add further process ``` > ```java BarcodeReader.initLicense("YOUR-LICENSE-KEY"); BarcodeReader reader = new BarcodeReader(); reader.initRuntimeSettingsWithString("{\"Version\":\"3.0\", \"ImageParameter\":{\"Name\":\"high-density-qr-tpl\",\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[{\"Mode\":\"LM_CONNECTED_BLOCKS\"}],\"ScaleUpModes\": [{\"Mode\": \"SUM_LINEAR_INTERPOLATION\",\"AcuteAngleWithXThreshold\": 0,\"ModuleSizeThreshold\": 4,\"TargetModuleSize\": 6}],\"ScaleDownThreshold\":10000,\"Timeout\":5000}}}", EnumConflictMode.CM_OVERWRITE); TextResult[] result = reader.decodeFile("YOUR-IMAGE-FILE-PATH", ""); // Start decoding // Add further process ``` > ```csharp string errorMsg; EnumErrorCode iRet = BarcodeReader.InitLicense("YOUR-LICENSE-KEY", out errorMsg); if (iRet != EnumErrorCode.DBR_SUCCESS) { Console.WriteLine(errorMsg); } BarcodeReader reader = new BarcodeReader(); reader.InitRuntimeSettingsWithString("{\"Version\":\"3.0\", \"ImageParameter\":{\"Name\":\"high-density-qr-tpl\",\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[{\"Mode\":\"LM_CONNECTED_BLOCKS\"}],\"ScaleUpModes\": [{\"Mode\": \"SUM_LINEAR_INTERPOLATION\",\"AcuteAngleWithXThreshold\": 0,\"ModuleSizeThreshold\": 4,\"TargetModuleSize\": 6}],\"ScaleDownThreshold\":10000,\"Timeout\":5000}}}", EnumConflictMode.CM_OVERWRITE, out errorMsg); TextResult[] result = reader.DecodeFile("YOUR-IMAGE-FILE-PATH", ""); // Start decoding // Add further process ``` > ```cpp char errorBuf[512]; int iRet = -1; iRet = dynamsoft::dbr::CBarcodeReader::InitLicense("YOUR-LICENSE-KEY", errorBuf, 512); if (iRet != DBR_OK) { cout << errorBuf << endl; } CBarcodeReader* reader = new CBarcodeReader(); reader->InitRuntimeSettingsWithString("{\"Version\":\"3.0\", \"ImageParameter\":{\"Name\":\"high-density-qr-tpl\",\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[{\"Mode\":\"LM_CONNECTED_BLOCKS\"}],\"ScaleUpModes\": [{\"Mode\": \"SUM_LINEAR_INTERPOLATION\",\"AcuteAngleWithXThreshold\": 0,\"ModuleSizeThreshold\": 4,\"TargetModuleSize\": 6}],\"ScaleDownThreshold\":10000,\"Timeout\":5000}}}", CM_OVERWRITE, errorBuf, 512); reader->DecodeFile("YOUR-IMAGE-FILE-PATH", ""); // Start decoding // Add further process ``` > ```c int iRet = -1; char errorBuf[512]; iRet = DBR_InitLicense("YOUR-LICENSE-KEY", errorBuf, 512); if (iRet != DBR_OK) { printf("%s\n", errorBuf); } void* barcodeReader = DBR_CreateInstance(); DBR_InitRuntimeSettingsWithString(barcodeReader, "{\"Version\":\"3.0\", \"ImageParameter\":{\"Name\":\"high-density-qr-tpl\",\"DeblurModes\":[{\"Mode\":\"DM_SHARPENING\"},{\"Mode\":\"DM_GRAY_EQUALIZATION\"}],\"ExpectedBarcodesCount\":1,\"LocalizationModes\":[{\"Mode\":\"LM_CONNECTED_BLOCKS\"}],\"ScaleUpModes\": [{\"Mode\": \"SUM_LINEAR_INTERPOLATION\",\"AcuteAngleWithXThreshold\": 0,\"ModuleSizeThreshold\": 4,\"TargetModuleSize\": 6}],\"ScaleDownThreshold\":10000,\"Timeout\":5000}}}", CM_OVERWRITE, errorBuf, 512); DBR_DecodeFile(barcodeReader, "YOUR-IMAGE-FILE-PATH", ""); // Start decoding // Add further process ```