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A tale of two codecs. Or how not to be a standard.

I’ve just bought a new digital SLR camera. Being a dyed in the wool Pentax person, I’ve upgraded to their new K7.

Being fairly serious about (some of) my photography I shoot quite a lot in RAW format.(In case you didn’t know higher end digital cameras can save the data as it comes off their sensor without converting it to JPEG format). There are only a small number of ways of expressing RAW data but every camera maker embeds one of those methods into their own file format: then each new camera introduces a new sub-version of the format. This is, frankly, a right pain.

Adobe came up with an answer to this, Digital Negative format, DNG. It has been adopted, but not Widely.  Pentax were first to support it in parallel with their own PEF format; Heavyweights like Hassleblad and Leica support it, so do some models from Casio, Ricoh and Samsung. But Canon and Nikon who account for somewhere round 3/4 of all DSLR sales have stuck with their own formats. Adobe maintain a converter which take proprietary files and convert them to DNG, so if you have an application which supports DNG but not your specific camera, Adobe’s tool will bridge the gap. So the take-up in photo processing software has been quite good. My chosen RAW software Capture One needs an update to work with the latest PEF, but will take DNG files straight from the camera. And I’d switch the camera over from PEF to DNG format if it weren’t for the vexing matter of Codecs. 

Before Windows Vista shipped we introduced “Windows Imaging components” WIC, which provide  RAW file using imaging CoDecs (COmpressor DECompressor). Windows 7 and Vista include WIC, and it’s WIC which provides image preview in the explorer: the net effect is that if you have a suitable Codec you get image preview. But, only a very basic set of codecs ships with the OS, partly because of the maintenance headache and partly because some RAW processing requires a bit of reverse engineering and we try to avoid doing that. Camera vendors provide Codecs and Pentax had a new PEF Codec on-line when I got my K7 home. But this is 32 bit only – other camera makers also lack 64 bit support. I could take this as inspiration for a huge rant  but let’s just say I’d make it a requirement for 32 AND 64 bit Windows to be able to preview a camera’s files before it was granted the “certified for Vista” logo - which the K7 sports on its packaging. Perhaps it’s good for our partnerships that I don’t decide such things.

I was on 64 bit Vista and I’m now on 64 bit Windows 7, so you might think the 32 bit codec would be totally useless … but no. A 32 bit codec won’t work with 64 bit software, like Windows explorer. But it will work with a 32 bit program like Windows Live Photo Gallery. (Photo Gallery from Vista has been moved over to Windows Live). Since WLPG shares a thumbnail cache with explorer, anything which you have seen in the Gallery will get a thumbnail in Explorer.  Now, granted, this is a Kludge but there are worse ones out in the world - so I can see my PEFs. But using PEF format means I need to use the (less than great) bundled RAW software until Capture one support the revised PEF. If I want to use Capture one today, I need to use DNG. So  do Adobe have a DNG codec ? They do, but their web site has (unanswered) complaints about the lack of 64 bit support going back to May of last year. Unlike the Pentax codec the Adobe one catches that I am on 64 bit Windows 7 and tells me it only installs on 32 bit Vista. [Users with the Windows Imaging Components installed on XP are out of luck too].

It’s a pretty poor show on Adobe’s part, but it’s easy to see how this comes about. None of the Camera vendors see it as their job to write a Codec for DNG – especially as Adobe have started the process. Microsoft don’t write Codecs except for major standards like JPG, PNG and TIFF and our own formats like Windows Media photo:  DNG doesn’t have enough of a foothold to be classed as a major standard. Adobe – I suspect – must feel that too many people are and not pulling their weight – expecting them to do all the work. It’s perhaps unfair to draw a parallel our support for Linux in the virtualization world (which I have only just written about) – after all it is in our interest to get our virtualization platform adopted, Adobe aren’t disadvantaged if people don’t choose to adopt DNG. But it needs a bit more commitment to get something adopted than Adobe are showing. If you were a product planner at Canon or Nikon would you write DNG support into the spec for future models ? Or would you decide that the support for DNG was half baked and you’d leave it as “something to keep an eye on” for now ?

In researching this I had a look at the Microsoft’s pro photo web site. Which is worth a visit just for the “Icons of imaging” page if you haven’t been there before. The downloads page does feature a 3rd party codec for DNG , which I must investigate. Sadly it’s not free: it’s not that I begrudge the money, but if I have to pay even a token amount to get something which bundled with something I have bought and is supposed to be a standard, to working in the all the places I’d expect it work then how much of a standard is it. I could level the same charge at Adobe over PDF iFilters and preview – but as I’ve written before, Foxit software plugs the gaps  and is free – reinforcing the idea that PDF is a standard which is bigger than the company which devised it. I’d love to think DNG would do for RAW formats what PDF has done for documents, but sadly it doesn’t look like it will go that way.