[texhax] help

[Lars Madsen]

> _______________________________________
> From: Reinhard Kotucha <reinhard.kotucha at web.de>
> Sent: 22 November 2018 01:24
> To: Lars Madsen
> Cc: Peter Flynn; reinhard.kotucha at web.de; TeXhax
> Subject: Re: [texhax] help
> 
> On 2018-11-21 at 12:00:35 +0000, Lars Madsen wrote:
> 
>  > Reinhard, thanks for mentioning this, I never even realised that
>  > PNG was an issue link that.
>  >
>  > Do you have more information about this? Especially which is better
>  > to use for quality (and speed)
> 
> Hi Lars,
> do you ask whether PNG or PDF bitmaps are better?  You don't have a
> choice anyway because PDF doesn't support PNG.  So the question is
> whether sam2p or libpng is better.
> 

I don't think many users know that PDF does not support PNG (I didn't)

I'm looking for information as to what we should recommend to our
users, and what we should use in our projects.

> Péter Szabó told me that sam2p removes redundancy from bitmap images
> without degrading quality. This is possible because there is not only
> one way to create a valid PNG file.
> 
> As far as speed is concerned, I think that it's more efficient to
> convert PNG to PDF in advance because the PDF file can be used as-is,
> without any further processing.
> 

I agree completely, there is a very noticable compilation stop at
every included PNG.


> Aside from the fact that sam2p supports zillions of bitmap formats, it
> always creates very small files.
> 
> PostScript didn't support compression prior to PS Level 2.  But even
> if your ancient PostScript interpreter doesn't support Level 2, sam2p
> is able to support compression though.  It "simply" adds a
> de-compressor written in PostScript to the file.  Péter obviously had
> file size in mind from the beginning.
> 
>  > I did a test on a preprint, where if we use PNG versions of some
>  > tif files it ends up at 50Mb, converting the tifs to pdf using
>  > sam2p reduced this to 30.
> 
> I'm not surprised.
> 
> Lars, I must admit that I wasn't aware of sam2p and textrace until I
> spent a whole evening with Péter Szabó at the ENST cafeteria during
> EuroTeX 2003 in Brest while you preferred to waste your time at the
> conference dinner. ;)
> 

oy, that was the first conference I ever went to, so I only folloew
the flow.

> Regards,
>   Reinhard
> 
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