Support for HDR Images

[eastern_strider]

I'm thinking of developing an High Dynamic Range (HDR) image processing tool. I would like to use Magick++ as the underlying image processing library thanks to its robustness and efficiency. My questions are:

1) Is it possible to work with floating point data types in Magick++? If yes, should the data range be between normalized between [0,1]?

2) Is there a read/write support for HDR file formats?

3) How is the conversion between HDR and LDR formats handled? Is there any tone mapping algorithm implemented?

Thank you very much for any answers.
eastern_strider

[magick]

ImageMagick permits HDR with the --enable-hdri configure script option at build time. For HDR the pixel components are floating point and are normalized to the QuantumRange (for Q16 the values range from negative to 65535.0 and beyond). ImageMagick supports some HDR formats such as EXR, PFM, MIFF, etc. Currently we do have not implemented any tonal mapping algorithms.

[eastern_strider]

I'm doing my Ph.D. on HDR imaging and I'd love to implement some of the commonly used tone mapping algorithms into ImageMagick. I'll try to get myself familiar with the interface first.

Thanks,
eastern_strider

[dognose]

Is it just me, or people mean two different things when talking about HDR images?

Maybe I'm just not understanding things right though..

It seems like there is the HDR file format, for storing high quality images. Then, there is the HDR effect, which is "simulated" HDR. For the HDR effect, images taken at different exposures, then tonally mapped or blended the exposure somehow into a combined image. The input and output images here aren't necessarily in HDR file format, even though they are called HDR images.

It seems that IM can do some of these effects without the direct hdr file format. Is that right?

[anthony]

In IM terms. HDRI is a image file format. But it is also a Compile time quality setting.

basically if Im have been compiled as HDRI, it will use floating point (double) values to hold images in memory, allowing image processing of the image to use a dynamic floating point numbers rather than a fixed integer quality bit level.

See http://imagemagick.org/Usage/basics/#hdri

That in turn allows HDRI images to be processed to produce HDRI images.

At this time however no one has published any HDRI methods to make use of these high quality compile time option.