topic Re: Picnic curiositiy in Intel® Integrated Performance Primitives

Picnic curiositiy

turks — Fri, 27 Feb 2009 22:27:23 GMT

I'm testing some of the JPEG and JPEG2000 features of IPP 6.0 update using the Picnic app. If I open the resultant files
in Photoshop, the dpi is always 72 dpi and the wrong size. For instance a 4inch x 4inch 300dpi JPEG saved out of Picnic
shows in Photoshop as 72 dpi and a width and height of 16.667 inches. Is there meta data that defines the dpi ?

Thanks

Re: Picnic curiositiy

Thomas_Jensen1 — Sat, 28 Feb 2009 10:42:18 GMT

I have also seen this lack of pixel size (dpi) meta data handling in IPP (all versions) with Jpeg and Jpeg2000.
I had to patch the IPP samples source code to add load/save of pixel size; and with each new IPP samples update, I must redo the patching.

I have also added this issue as a Premier Support item, but it has now been there as a feature request for several years.

I really think IPP should support this because both Jpeg and Jpeg2000 (and Jpeg XR) has meta fields for it.

Re: Picnic curiositiy

Vladimir_Dudnik — Mon, 02 Mar 2009 17:57:27 GMT

Hello,

The possibility to get and store image resolution information was added to UIC JPEG codec in IPP 6.0. Please see JPEGDecoder/JPEGEncoder API

void GetJFIFApp0Resolution(JRESUNITS* units, int* xDensity, int* yDensity);
void SetJFIFApp0Resolution(JRESUNITS units, int xdensity, int ydensity)

Adding similar API for JPEG2000 codec is in plan for the future releases.

Regards,
Vladimir