[reportlab-users] JBIG2 (Re: Optimizing greyscale and bilevel images)

[Jesus Cea]

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On 29/12/11 00:35, Jesus Cea wrote:

> On 29/12/11 00:00, Jesus Cea wrote:

>> I have bilevel PNG files that when printed as PDF using

>> reportlab are expanded THREE times.

> 

> Using my patch, the final PDF file size is HALF of the unpatched 

> ReportLab, when the source is bilevel images.


Experimenting with this, I am messing with JBIG2. PDF 1.4 supports it
natively. ReportLab generates PDF 1.3.

PIL doesn't support jbig2 at all, but PDF 1.4 supports it natively, so
would be trivial to include a jbig2 image in a (1.4) PDF file, given a
filename and a jbig2 file on disk/object wrapper.

Is there any reason to generate PDF 1.3 files instead of 1.4?. Or 1.7,
BTW.

Any interest in supporting JBIG?.

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