Tips to Solve Common Problems Reading Barcodes

Unlock the Information Behind Those Bars With ImageRamp or ChronoScan

Copyright ©2014

Preprocessing Tips for Improved Barcode Recognition

The best barcode recognition starts with setting the highest standards for your forms and scanning workflow if possible.

Set standards for pixels per element in your barcoded forms. For 1D barcodes, at least three pixels bar length. For 2D use modules of 4 or 5 pixels.

Set standards for pixels per element in your barcoded forms. For 1D barcodes, at least three pixels bar length. For 2D use modules of 4 or 5 pixels.

Avoid variable length barcodes as they may force fit the code into a fixed area. If you have to use variable length, set a maximum size

and account for that on your document.

Set standards for pixels per element in your barcoded forms. For 1D barcodes, at least three pixels bar length. For 2D use modules of 4 or 5 pixels.

Avoid variable length barcodes as they may force fit the code into a fixed area. If you have to use variable length, set a maximum size

and account for that on your document.

If possible, orient 1D barcodes horizontally as most scanners pull the paper through the scanner from the shorter side. This orientation is least affected by scan slippage that can distort the barcode.

Set standards for pixels per element in your barcoded forms. For 1D barcodes, at least three pixels bar length. For 2D use modules of 4 or 5 pixels.

Avoid variable length barcodes as they may force fit the code into a fixed area. If you have to use variable length, set a maximum size

and account for that on your document.

If possible, orient 1D barcodes horizontally as most scanners pull the paper through the scanner from the shorter side. This orientation is least affected by scan slippage that can distort the barcode.

Do not locate barcodes on forms where they may be stapled or clipped and leave plenty of white space around barcodes, optimally ¼ inch.

Test to determine the lowest acceptable scan resolution, usually 300 dpi.

Set standards for pixels per element in your barcoded forms. For 1D barcodes, at least three pixels bar length. For 2D use modules of 4 or 5 pixels.

Avoid variable length barcodes as they may force fit the code into a fixed area. If you have to use variable length, set a maximum size

and account for that on your document.

If possible, orient 1D barcodes horizontally as most scanners pull the paper through the scanner from the shorter side. This orientation is least affected by scan slippage that can distort the barcode.

Do not locate barcodes on forms where they may be stapled or clipped and leave plenty of white space around barcodes, optimally ¼ inch.

Test to determine the lowest acceptable scan resolution, usually 300 dpi.

Set standards for pixels per element in your barcoded forms. For 1D barcodes, at least three pixels bar length. For 2D use modules of 4 or 5 pixels.

Avoid variable length barcodes as they may force fit the code into a fixed area. If you have to use variable length, set a maximum size

and account for that on your document.

If possible, orient 1D barcodes horizontally as most scanners pull the paper through the scanner from the shorter side. This orientation is least affected by scan slippage that can distort the barcode.

Do not locate barcodes on forms where they may be stapled or clipped and leave plenty of white space around barcodes, optimally ¼ inch.

No colored backgrounds.

Skewed Barcode

ImageRamp and ChronoScan can read many skewed barcodes using default settings, but some barcodes may require adjustments to the barcode settings.

Try setting SkewTolerance to a value between 1 and 5. SkewTolerance controls the maximum angle from the horizontal or vertical at which a barcode will be recognized by the toolkit.

Try setting SkewTolerance to a value between 1 and 5. SkewTolerance controls the maximum angle from the horizontal or vertical at which a barcode will be recognized by the toolkit.

The LineJump property controls the frequency with which the toolkit samples scan lines as it moves through an image. Increasing the value of the LineJump

property will increase the speed at which an image is processed but may decrease the read rate.

Noisy Background

With this problem, the entire image will typically contain black dots in the background.

Try setting the NoiseReduction to a value between 5 and 10. If a value is specified in this setting, the toolkit will run an image through a noise reduction filter and remove marks that are unlikely to be part of a barcode before interpreting the barcodes. Use caution with larger values in this setting as larger values remove larger marks from the image which could destroy vital barcode information.

Try setting the NoiseReduction to a value between 5 and 10. If a value is specified in this setting, the toolkit will run an image through a noise reduction filter and remove marks that are unlikely to be part of a barcode before interpreting the barcodes. Use caution with larger values in this setting as larger values remove larger marks from the image which could destroy vital barcode information.

Try setting the MedianFilter. When this setting is set to True, the toolkit will apply a median filter to the image before checking for barcodes. This

is a useful option for high resolution images that contain speckles of black and white. It is not recommended for images where the black bars

or white spaces are less than 2 pixels wide.

Try setting the NoiseReduction to a value between 5 and 10. If a value is specified in this setting, the toolkit will run an image through a noise reduction filter and remove marks that are unlikely to be part of a barcode before interpreting the barcodes. Use caution with larger values in this setting as larger values remove larger marks from the image which could destroy vital barcode information.

Try setting the MedianFilter. When this setting is set to True, the toolkit will apply a median filter to the image before checking for barcodes. This

is a useful option for high resolution images that contain speckles of black and white. It is not recommended for images where the black bars

or white spaces are less than 2 pixels wide.

Try the UseOverSampling setting. When UseOverSampling is True the barcode reader samples 3 lines at a time (skipping 2 lines between each sample) and takes the average pixel value. This is useful for images containing both black and white speckles.

White Speckles in the Bars

In this case the image will typically contain black dots in the background and white dots in the black bars.

Try setting NoiseReduction to a value between 5 and 10 and Despeckle to True.

Try setting NoiseReduction to a value between 5 and 10 and Despeckle to True.

Try setting the MedianFilter. When this setting is set to True, the toolkit will apply a median filter to the image before checking for barcodes. This

is a useful option for high resolution images that contain speckles of black and white. It is not recommended for images where the black bars or

white spaces are less than 2 pixels wide.

Try setting NoiseReduction to a value between 5 and 10 and Despeckle to True.

Try setting the MedianFilter. When this setting is set to True, the toolkit will apply a median filter to the image before checking for barcodes. This

is a useful option for high resolution images that contain speckles of black and white. It is not recommended for images where the black bars or

white spaces are less than 2 pixels wide.

Try the UseOverSampling setting. When UseOverSampling is True the barcode reader samples 3 lines at a time (skipping 2 lines between each sample) and takes the average pixel value. This is useful for images containing both black and white speckles.

Badly Defined Edges

In these cases the bars have joined together in certain places, which makes it difficult for the toolkit to separate the bars and determine their relative sizes.

Try setting NoiseReduction to a value between 10 and 20.

Try setting NoiseReduction to a value between 10 and 20.

Try rescanning at a higher resolution.

Lines and Other Marks too Close to

the Barcode

Most barcodes should have a quiet zone around the barcode to distinguish the barcode from the rest of the image; however, as in the example below, it’s not unusual for barcodes to be printed in boxes which interfere and may result in the barcode being ignored by the toolkit.

The LineJump property controls the frequency with which the toolkit samples scan lines as it moves through an image. Increasing the value of the LineJump property will increase the speed at which an image is processed but may decrease the read rate.

The LineJump property controls the frequency with which the toolkit samples scan lines as it moves through an image. Increasing the value of the LineJump property will increase the speed at which an image is processed but may decrease the read rate.

Try setting the MaxLength. MaxLength defines the largest length for a barcode string, including checksum characters.

The LineJump property controls the frequency with which the toolkit samples scan lines as it moves through an image. Increasing the value of the LineJump property will increase the speed at which an image is processed but may decrease the read rate.

Try setting the MaxLength. MaxLength defines the largest length for a barcode string, including checksum characters.

Try setting the MinLength. MinLength defines the smallest length for a barcode string, including checksum characters.

Learn More:

For more on:• Batch Document processing• Batch PDF mining• Batch TIF mining• Extracting meta data,• Intelligent data capture• Data extraction• Document scanning • Extracting data• Extract meta data, • Scanner software, • Barcode recognition, • Capture tutorial • Pdf scanning,• Scanning software • Indexing• Document indexing• Automated capture• Meta data • Scan to index• Docufi• Imageramp• Data capture• Chronoscan• Barcode scanning• Improve barcode scanning• Barcode tips• Barcode problems• Solve barcode errors

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