IsBlank Method (GdPictureImaging)

Discussions about image processing and document imaging.
Post Reply
mtnguyen
Posts: 2
Joined: Mon Nov 13, 2017 11:33 pm

IsBlank Method (GdPictureImaging)

Post by mtnguyen » Mon Dec 11, 2017 4:47 am

Hi,

Is there any different between V11 and V14 regarding IsBlank Method?
As I have just upgraded to V14 to utilise OCRPages method but just noticed that the IsBlank method returns different results for the same Multipage TIF image. The method was called as follows:

if (m_GdPictureImaging.IsBlank(m_ImageID, float.Parse(this.tifToPDFConfig.DeleteBlanksBlankPixelThresholdInt), true))

this.tifToPDFConfig.DeleteBlanksBlankPixelThresholdInt was set to 99.95

Note: before making this post, I have downloaded the latest version 14.0.0.27. The version that had the different result was 11.2.0.7.

Regards

David
Posts: 65
Joined: Mon Feb 08, 2016 3:12 pm

Re: IsBlank Method (GdPictureImaging)

Post by David » Tue Dec 12, 2017 11:47 am

Hi,

We have changed the blank page detection in order to improve its accuracy. This change might request a slight change of the threshold under certain circumstances.

Feel free to share the impacted images in case you need us to have a look.

Regards,

David

mtnguyen
Posts: 2
Joined: Mon Nov 13, 2017 11:33 pm

Re: IsBlank Method (GdPictureImaging)

Post by mtnguyen » Thu Dec 14, 2017 1:45 am

Hi David,

I attached my test images. This is the process that we have been using with Ver 11 for TIF to PDF Ocr:
1. Remove punch holes on even pages only using GdPictureImaging.RemoveHolePunch
- Note: Ver 11 does not have AccountForPunchHoles in IsBlank method and with Ver 14 I can remove this function.

2. Auto rotate

3. Detect and delete blank page on even pages only using GdPictureImaging.IsBlank(m_ImageID, float.Parse(this.tifToPDFConfig.DeleteBlanksBlankPixelThresholdInt), true)
Add or delete page based on IsBlank result with threshold = 99.95:
- GdPictureImaging.TiffAddToMultiPageFile(m_ImageID, i, tiffcompression)
- GdPictureImaging.TiffDeletePage(m_ImageID, i)

4. OCR using GdPictureImaging.PdfOCRCreateFromMultipageTIFF
**Note:

Two tests was run with referencing to Ver 11 and 14 with exact same setting and Ver 11 seems to be better.

You mentioned the the blank page detection was changed. So is there an equivalent scale? As we have been using different settings for different groups of document.

I am looking forward to be able to use V14 with its OCRPages method and PDFCompression settings.

Regards,
Tri
Attachments
TestDoc.zip
(1.99 MiB) Downloaded 3 times

User avatar
Loïc
Site Admin
Posts: 5538
Joined: Tue Oct 17, 2006 10:48 pm
Location: France
Contact:

Re: IsBlank Method (GdPictureImaging)

Post by Loïc » Thu Dec 21, 2017 6:44 pm

Hi,

What are we supposed to do with the image? Could you provide a code snippet and describe the expected result vs the obtained result?

Kind regards,

Loïc

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest