[PDFBOX-4598] oversized jbig2 decoded result that causing unnecessary operation

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0.2 JBIG2
• Fix Version/s: 3.0.3 JBIG2
• Component/s: JBIG2
• Flags: Patch
• Assignee: Tilman Hausherr
• Reporter: Hee Jeong Kim
• Created: 17/Jul/19 05:19
• Updated: 18/Dec/19 18:58
• Resolved: 21/Jul/19 07:36

Description

Hi! I am using pdfbox 2.0.16 and jbig2-imageio 3.0.2 to read JBIG2 images, and found some issue to report.

It seems like jbig2-imageio creates oversized BufferedImage, and this also makes pdfbox to do unnecessary operations.

To read Jbig2 image, pdfbox with jbig2-imageio do followings:

1. find JBIG2 ImageReader (https://github.com/apache/pdfbox/blob/2.0.16/pdfbox/src/main/java/org/apache/pdfbox/filter/JBIG2Filter.java#L67)

2. read Image and get BufferedImage as a result (https://github.com/apache/pdfbox/blob/2.0.16/pdfbox/src/main/java/org/apache/pdfbox/filter/JBIG2Filter.java#L106)

2-1. JBIG2 ImageIO 3.0.2 get decoded bitmap (https://github.com/apache/pdfbox-jbig2/blob/3.0.2/src/main/java/org/apache/pdfbox/jbig2/JBIG2ImageReader.java#L249)

2-2. return the given bitmap as buffered image (https://github.com/apache/pdfbox-jbig2/blob/3.0.2/src/main/java/org/apache/pdfbox/jbig2/JBIG2ImageReader.java#L259)

The problem is
At step 2-1, roughly 59MB Bitmap is created for given Jbig2 image on the second page of sample.pdf (which is correct),
but oversize(473MB, roughly) BufferedImage is returned at the step 2-2.

I think this is because jbig2-imageio uses a raster based on a PixelInterleavedSampleModel and IndexColorModel with 8 bits.
https://github.com/apache/pdfbox-jbig2/blob/3.0.2/src/main/java/org/apache/pdfbox/jbig2/image/Bitmaps.java#L177
https://github.com/apache/pdfbox-jbig2/blob/3.0.2/src/main/java/org/apache/pdfbox/jbig2/image/Bitmaps.java#L286
https://github.com/apache/pdfbox-jbig2/blob/3.0.2/src/main/java/org/apache/pdfbox/jbig2/image/Bitmaps.java#L291

This also makes pdfbox to check a pixel size of the color model of result buffered image,
https://github.com/apache/pdfbox/blob/2.0.16/pdfbox/src/main/java/org/apache/pdfbox/filter/JBIG2Filter.java#L116

and to create another BufferedImage with binary type since it is not 1. (jbig2 is 1-bit depth)
https://github.com/apache/pdfbox/blob/2.0.16/pdfbox/src/main/java/org/apache/pdfbox/filter/JBIG2Filter.java#L122

I think we should call createPackedRaster and use the returned raster which is based on MultiPixelPackedSampleModel, and use IndexColorModel with 1 bits since jbig2 is for bi-level image. Please check the attached patch. I tested with the patch, and it seems like this patch works well.

You can reproduce this issue with the second of the sample.pdf file that I attached.
You can also download the file from here: http://www.newsgn.com/data/newsgn_com/pdf/201802/2018022229524590.pdf