Comments on: What is HD-JPEG? http://blog.forret.com/2007/10/what-is-hd-jpeg/ Tango, photography and whatever's bleeding edge Wed, 17 Mar 2010 02:53:04 +0000 http://wordpress.org/?v=2.9.1 hourly 1 By: Peter http://blog.forret.com/2007/10/what-is-hd-jpeg/comment-page-1/#comment-156699 Peter Tue, 09 Oct 2007 07:34:50 +0000 http://blog.forret.com/2007/10/what-is-hd-jpeg/#comment-156699 I'm not sure. The main purpose of OpenEXR is to have a larger dynamic range in the color/luminance description of each pixel so that if you decide to light it more or less (e.g. 7 stops brighter) you don't lose all the detail. In digital, one stop brighter means multiplying every value with 2, so all values above 128 become clipped (for 8-bits per color). Seven stops brighter: each pixel becomes either 0, 128 or 256. You can imagine the quality of the picture then. It is true that most HDR pictures are taken by photographing the same scene with different exposures, but this is because of the limitations of the camera. It can then be stored either as a combination of 3 regular JPEGs or as one OpenEXR image. Check the OpenEXR samples: http://www.openexr.com/samples.html I’m not sure. The main purpose of OpenEXR is to have a larger dynamic range in the color/luminance description of each pixel so that if you decide to light it more or less (e.g. 7 stops brighter) you don’t lose all the detail. In digital, one stop brighter means multiplying every value with 2, so all values above 128 become clipped (for 8-bits per color). Seven stops brighter: each pixel becomes either 0, 128 or 256. You can imagine the quality of the picture then.

It is true that most HDR pictures are taken by photographing the same scene with different exposures, but this is because of the limitations of the camera. It can then be stored either as a combination of 3 regular JPEGs or as one OpenEXR image.

Check the OpenEXR samples: http://www.openexr.com/samples.html

]]> By: Mike http://blog.forret.com/2007/10/what-is-hd-jpeg/comment-page-1/#comment-156685 Mike Tue, 09 Oct 2007 06:22:01 +0000 http://blog.forret.com/2007/10/what-is-hd-jpeg/#comment-156685 I assume that OpenEXR saves multiple images as in digital photography until now, HDR as good as always consists of multiple images? I assume that OpenEXR saves multiple images as in digital photography until now, HDR as good as always consists of multiple images?

]]> By: google » What is HD-JPEG? http://blog.forret.com/2007/10/what-is-hd-jpeg/comment-page-1/#comment-156420 google » What is HD-JPEG? Mon, 08 Oct 2007 18:59:08 +0000 http://blog.forret.com/2007/10/what-is-hd-jpeg/#comment-156420 [...] Check it out! While looking through the blogosphere we stumbled on an interesting post today.Here’s a quick excerptWhile reading the specs of the PackardBell Store & Play , I fall upon ” Foto formaten: JPEG, HD JPEG ” As I am working with several aspects of HD video all the time, I am of course intrigued. [...] [...] Check it out! While looking through the blogosphere we stumbled on an interesting post today.Here’s a quick excerptWhile reading the specs of the PackardBell Store & Play , I fall upon ” Foto formaten: JPEG, HD JPEG ” As I am working with several aspects of HD video all the time, I am of course intrigued. [...]

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