[luatex] handling resolution of jpg files

[luigi scarso]

On Fri, Jan 13, 2017 at 7:01 PM, luigi scarso <luigi.scarso at gmail.com> wrote:

> From
> https://msdn.microsoft.com/en-us/library/ms932271.aspx
> PropertyTagPixelPerUnitX
> Pixels per unit in the x direction.
> Tag 0x5111
> Type PropertyTagTypeLong
> Count 1
>
> PropertyTagPixelPerUnitY
> Pixels per unit in the y direction.
> Tag 0x5112
> Type PropertyTagTypeLong
> Count 1
>
> PropertyTagPixelUnit
> Unit for PropertyTagPixelPerUnitX and PropertyTagPixelPerUnitY.
> A setting of 0 indicates that property is unknown.
> Tag 0x5110
> Type PropertyTagTypeByte
> Count 1
>
> but these tags does not affect the resolution.

hm, not true. I can use
http://www.libpng.org/pub/png/book/chapter11.html#png.ch11.div.8
as reference.

-- 
luigi