dlRaw

Hi folks,

just a few lines to let you know, that the project is not dead So in the last days I've worked on one important part of RAW processing, the demosaicing. Additional filters were added, and with these image quality can be improved.

Demosaicing is the part which creates from the Bayer pattern the actual image right at the beginning of the processing. This is important when it comes down to details, noise and sharpness (and of course artifacts ). We're mostly talking on pixel level here, so the differences are not that big (100% view in the 1:1 pipe). I've prepared two small losslessly compressed samples (the RAWs are kindly provided by imaging-resource, I took the ISO 100 and ISO 25600 shots). So just download the files yourself and play with the settings on the 1:1 pipe (otherwise the demosaicing filters won't affect the output) to see if you can get similar results with the current version without these algorithms Only settings on the camera tab are used, no additional sharpening or denoising, and no wavelet denoising on the RAW. Sure it is not perfect, but an improvement. You won't see the detail differences very often, because you really need fine structures for this, eg small patterns (moire areas) of fine bright hairs (like whiskers)... The differences in the noise on high ISO shots are far more prominant. Of course improved quality doesn't come for free, the calculation times are much higher, but it is still bearable with a modern multicore CPU, all of them are already parallelized (demosaicing of 10 MP on a Q6600 with very good quality and many refinement steps takes around 10 seconds). For more information, there is a nice comparison of demosaicing algorithms here. So, have fun to explore your RAW files for these fine structures and stay tuned for the next release

greets mike

Hi folks,

just a short update, to let you know, that work is still preceding... You probably noticed my last pictures on the blog. They are pretty clean as you see them there, but while processing them I had a problem with hotpixels. My old and trusty Pentax K100D has some bad pixels when used with higher ISO. Although it's not so bad on the pure picture, when sharpening the image bad pixels like to shine out So I had to remove these small blemishes on all of them manually in gimp afterwards... Of course I didn't like that During the week I tried to code an algorithm removing them; finally today I can report first results.

The algorithm works at the moment only on 1:2 and 1:4 images, because on 1:1 pipe it is better to work on the Bayer pattern directly and that is still work in progress... But on 1:2 I'm pretty satisfied with the result. The two attached images are both way oversharpened, that is just to show you how many bad pixels there are. Usually, with normal sharpening, one would only see a view of them, but those would still be distracting. The difference between the two pictures is just the hotpixel reduction nothing more.

So stay tuned for more news about dlRaw

greets mike

Hi folks,

so here is a new dlRaw preview. But first the bad news. Last weekend Jos, the founder of dlRaw, announced that he will stop working on dlRaw. But without his help it would be to much work for me to get the SVN version to an equal level. So I won't switch to the SVN version any soon, I'll focus on stabilizing and improving the user experience for the preview.
This release follows this idea, not much new things, just getting a cleaner application. Some of the changes are:

• I've cut down the gimp plugin. Now you cannot start dlRaw as a gimp plugin, instead from the standalone dlRaw you get the lossless gimp export with exif and color profile. There are several reasons for this. First it is easier to maintain, furthermore there was a conflict with the tif extension so opening tif files in gimp was a problem and finally it is easier to install now. So for your workflow there should be no changes, from dlRaw to gimp with one click
• The crop tool was reworked. Now you can draw selections in all four directions and it is possible to show additional guide lines for improving the crop.
• There is an additional sharpen method, inverse diffusion sharpen from the CImg library. It acts completey different compared to the others and is able to give 'pixel sharpness'. Furthermore the usage of the CImg library was cleaned up.
• The dcraw integration has been updated, so dlRaw is on the same level as UFRaw 0.16 and allows RAW processing of many current cameras.
• The remember settings dialog has vanished. Now you can change this on an individual basis on the settings page (I know we need a preferences dialog...).
• dlRaw does not longer depend on the start directory, so you can move you dlRaw folder freely now.
• A few minor modifications to the GUI, 8-bit saving is back and some small bugs...

So that is it, download (20091024) and enjoy.

greets mike

Hi folks,

it has been a long time, but I felt, before taking the adventurous path to the trunk version with the flexible pipe, there should be some maintenance work on the old version. So besides flipping there is no new filter but there are some new things for your photography workflow.

• Probably the weakest point of dlRaw was saving, only Jpeg and Ppm and no metadata. So now it is possible to save in Jpeg, Ppm, Tiff and Png, and Jpeg and Tiff get the full exif and the chosen output color profile attached.
• The gimp integration is improved, so now one can choose which command starts gimp (which is nice for windows users) and also the chosen output color profile is sent to gimp. However at this stage I don't recommend using dlRaw as a plugin within gimp, instead use the standalone version and just send to gimp with the dedicated button.
• The histogram has two modes (like before) which you choose with the "output" control beneath it. If this setting is disabled you get the histogram at the end of the linear pipe, so at the end of the eyecandy tab. When "output" is enabled you get the histogram of the image you see on the screen, and furthermore in the settings dialog you can enable the use of the output profile. So this is the first step towards softproofing, dlRaw will calculate the histogram (and show the clipped values) with respect to the output profile (which takes additional time).
• Remember, there was this issue that images look dull in dlRaw right after opening them. So the reason is a different gamma handling compared to e.g. UFRaw. So now you'll find "sRGB gamma compensation" on the out tab, which mimiks the behaviour of the gamma handling in UFRaw for people who want that. Additional there is a base curve and a curve after gamma, which serve more sophisticated gamma corrections.
• Last not least there have been some small tweaks to the GUI and the order of the filters, that is just how I like it, and hopefully with the next preview you could change this on your own without recompiling.

Unfortunatelly there is also a bad message. Up to now I coundn't get the improved saving on windows, it seems there is an error in the imagemagick library, which we use for this. So at this point no windows version, but we try to fix this as soon as possible. On linux it works without problems (at least on my machine ).

So enough words, go check it out   Download!

greets mike

PS: Since dlRaw relies on qt4, the window uses your qt4 theme, mine looks like this.