REQ: Full 16+ bit/channel image support.

Ideas for improvements and requests for new features in XnView Classic

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REQ: Full 16+ bit/channel image support.

Post by JavaJones »

Apologies if this has been discussed before, but it is difficult to search for something like "16 bit" (many irrelevant results) and I did not find anything particularly relevant in browsing.

In short, what I would like to see is fully functional support for loading, manipulating, and saving 16+ bit *per channel* images. These are often referred to as "High Dynamic Range" or HDR, although this does not necessarily apply to all images that may be found in such a format.

Current behavior for XNView is interesting. It will *load* a 16bit/channel greyscale TIFF, for example, but if you try to save it, it will always save as 8 bit, and it indicates after loading that it is 8 bit as well.

Note that I am not asking for HDR Shop advanced functionality or anything. Simply for the existing functionality, loading and saving files *in particular*, be extended to support 16+ bit per channel formats in as many ways as possible, and for as many formats as allow 16+ bits per channel. This includes TIFF, PSD, PGM, PNG, RAW, OpenEXR, many "raw" digital camera files, and many others besides.

We are quickly coming to a time when many image files will be greater than 8 bit per channel, especially in the digital camera world, but also in the film industry, and others. XNview is a great tool for these uses and many besides, and it is increasingly important that 16 bit images be properly support. It is a good time to work heavily on making the XNView engine more flexible and functional for such images.

- Oshyan
Posts: 3
Joined: Sat Apr 11, 2015 8:26 pm

Re: REQ: Full 16+ bit/channel image support.

Post by Nachogaz »

Hi from Argentina!

I found this topic after a long search. I think I have a similar problem and would help any answer of XnView team. Unfortunately, I see that this topic is of 2005 and has not been answered yet. Being 2015, I have a similar problem with the ñatest version of XnView for Windows, so I try here anyway.

Working with Canon RAW (CR2) of T3i, 600D or higher, I found that XnView batch convert to TIFF uncompressed, lost the - "native filter "? - of sharpness. That is, RAW images opened in XnView have perfect focus (or, al least, the better has been obtained in the shot), but its derivative in TIFF is clearly "wrong focus" or blurred. Of course, after much testing, we discovered that the problem is not the focus, because the picture is the same and the open raw (which is a tiff at that moment, right?) looks properly. Since I am not an expert of digital imaging, I did some tests to rule out causes and find some direction to solve this. I Work in digitizing text, sharpness is a vital factor.

- First, as I mentioned before, I found the TIFF saved individually, that is, one by one, fully they retain the look of RAW, unlike what happens when we use batch conversion. (all in XnView)
- Second, I tried batch convert using the camera manufacturer's software (Canon Digital Photo Professional) and got good TIFF (same as raw), but twice weight (> 100Mb from a 25Mb RAW). Then applying a batch with XnView on these files and reweighed half, retaining their sharpness.
- Third, the images derived from the DPP are 48 bits, unlike that usually handle converting from XnView (therefore weigh twice) that are 24 (8 bits p/c, RGB), as Oshyan mentioned.

I get 2 conclusions:

1 - On the one hand I have the certainty that I'm losing a lot of information to use XnView batch convert (or XnConvert) since, in effect, does not support 16 bits per channel. Anyway, it's not my main concern, the -world of text-scanning tends contrast, even the binarization of images. So far, we can work well with 24-bit TIFF as they are sharp. But I fear that there is some connection between this and the second conclusion.

2 - (In the o h) At first, I thought maybe it was a matter of patents or rights or whatever, and that XnView did not have the complete code to convert a RAW to TIFF. Perhaps the sharpness value that is assigned to the camera while shooting, is metadata information somewhere in the file, that XnView not read. But then I think that if you can do when you open files individually, does not seem to be this.

in short, I ask for help about these doubts. We are very pleased with XnView and all its functions, it would be really cumbersome to have to include another workflow software for an intermediate step. But above all, I believe that Xn lacks nothing except this, and it saddens me. There is some reason to be so? Is there any solution? I do not know anything and therefore I am not applying?

I apologize for my English, I did my best (with a little help from G-T). I hope you can answer.

Of course, thank you very much and greetings!

- Nacho