On Sat, 15 Aug 2009 19:27:51 +0200 "Robert Schelander \(it-wms\)" <[email protected]> wrote:
| Hi, | | | | I don't know whether I should compile HDRI or not for my new server | installation. | | | | At the moment I don't work with HDRI. | | I usually only use convert to crop, resize, insert text and logos in webcam | pictures. The server handles approx. 100 cameras once per minute each. Input | and output format is always JPG at the moment. Sometimes the logos are | transparent PNG, GIF or EPG. | | | | Is there any advantage for my application to use HDRI? | | Are there any disadvantages? | HDRI becomes an advantage when you want to deal with images with floating point values and the enhanced quality that brings. None of the standard operations you specify have any real use for it. Actually all of them can use a faster more memory converitive IM Q8 version! Most user have no need of HDRI, not even for actual HDRI image processing! See http://www.imagemagick.org/Usage/basics/#hdri Basically HDRI replaces intergers with floating point values (and thus using more memory). This removes the 'white' and 'black' limits for colors, allowing users to temporarilly go beyond such limits, especially for highly mathematical image processing techniques. It also removes any rounding effects you may get from having to store modified color values in integers. For an example of both of these effects (and the only HDRI example in IM Examples currently available) see.. Reversed Image level Adjustments... http://www.imagemagick.org/Usage/color/#level_plus These HDRI examples may actually move to the first link I gave above, as a way of explaining the IM Q-level limitations. All other examples in IM Examples use a normal IM Q16 version, without any HDRI compile time option. Where HDRI is becoming VITAL is in the new enhancements for processing images using Fast Fourier Transforms (FFT). The examples, and tutorial, using FFT developed, even though it has been released. Enhacnments in FFT operators are also being developed. If you do not know what Fast Fourier Transforms or FFT processing is, and don't plan on doing image mathemathics, then you probable have no need for HDRI. Anthony Thyssen ( System Programmer ) <[email protected]> ----------------------------------------------------------------------------- At a video game, any kid could be in command, could make life and death decidions, on the glowing field of the screen. -- Dean Alan Foster, "The Last Starfighter" ----------------------------------------------------------------------------- Anthony's Home is his Castle http://www.cit.gu.edu.au/~anthony/ _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
