2004.11.06 21:06 "Re: [Tiff] Support for DNG tags", by Sachin Garg

I wish to support DNG images in my application and am currently using libtiff for tiff files. I recall a recent discussion regarding support of DNG tags in libtiff.

It will be great if libtiff can support DNG images too. Are there any plans to add DNG tags to libtiff anytime soon?

LibTIFF could read the tags

Yeah, I read that DNG is also TIFF based and libTIFF can support it. I am just curious if there are any plans to do so anytime soon.

Libtiff can already be used to support DNG. Libtiff can include updates (tag definitions) to make this more convenient. I have heard discussion among the libtiff developers about supporting DNG tags.

Yeah, I also read a related discussion in this list. I am just curious how soon we can expect such an update.

But I don't think libTIFF should try to decode (demosaic) the camera RAW data.

I couldnt get what you mean by this. Do mean that libTIFF _should_ ignore some specific tags?

Raster images are all about pixels. The camera RAW data requires some advanced knowledge and processing before it may be used as normal raster pixels. Even when libtiff "supports" DNG, the vast majority of the heavy lifting will be up to the application since libtiff is not going to translate the RAW data into pixels.

I will try to read more on this.

Sachin Garg [India]
http://www.geocities.com/schngrg