2004.11.05 19:44 "Re: [Tiff] Support for DNG tags", by Chris Cox

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.

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?

You need to read up on what Camera RAW data is -- it isn't RGB data. The raw sensor data has to go through some pretty extensive processing to get RGB data - that processing is demosaicing. Also, Camera RAW data typically uses lossless JPEG compression.

I'm saying that LibTIFF shouldn't be decompressing and demosaicing the Camera RAW data - it's too complex (and not easy to do well).

Chris