Archival Formats: JPEG 2000 vs HEIC


OK, I switched to using JPEG-2000 in 16-bit mode lossless for archiving images, this brings a 5400 dpi 35mm slide from 220MB to about 150MB. Moreover, you can also create a 16-bit lossy one and you get 16-bits.
Now that many camera phones can record more than 8-bit color (the iPhone is 10-bit), Apple has moved to HEIC and HEIF. This is a new container format and HEIF uses the H.265 compressor. You not get 16-bit images and smaller files too. Plus, this is how they get transparency and also they can include the motion video for Live Photos and even include information from their new portrait mode.
As an aside decoding Apple’s HEIC is not easy, they don’t have a single image, but have a collection of 256×256 tiles inside the file. This makes encoding easier on phones.
But what if you want to use this same format. Well, previously, I discovered that only Adobe Photoshop supports 16-bit JPEG-2000. The bad news is that I can’t find anything that supports 16-bit HEIC from Apple (their preview exports TIFFs to HEIC but only at 8 bits). So on to third party utilities.
Well there does seem to be a bit of a sea change coming. For a long time I’ve been storing images for viewing as 8-bit JPEGS and then saving Camera RAW for digital photos and then 16-bit TIFFs for scanned filHowever last year, I switched from 16-bit TIFFs to 16-bit JPEG-2000. The main reason is that JPEG-2000 uses wavelet compression and thus my 220MB 16-bit 5400dpi images from 35mm film shrunk to 150MB. Not a huge savings but better.
However with IOS 11, Apple switched to HEIF, High Efficiency Image Format, and that is a game changer. This is a new format based on the X.265 high efficiency codec that is used for movies. This is great for phones because X.265 is built in for video anyway and the encoding is very efficient for photos too. They also needed this because 8-bit JPEGs can’t handle all the colors that 10-bit cameras now capture. This is wonderful news because someday the interchange format with move to HEIF and with all these HDR color displays the images are really going to pop!
In fact, Apple changed the entire chain of image management so that HEIC is used inside iOS 11 and MacOS 10.13 High Sierra for everything, so right now I’m switched to exporting my archived files into HEIC. This is way better than the old export where  in IOS 10 you ended up with a JPEG a nd a Movie file for every photo. Now this is all included inside HEIC.
What does this mean? Well, for all my Live Photos, I need to reexport them. Right now I have as an underlying store a simple file system with jpg and a raw directory. The Raw has only held TIFFs from scans (and a few JPEG-2000 from the last year) and RAW from digital cameras. Now it will also hold HEIC.
The problem however is that right now it is very hard to find a convertor which will take TIFFs directly into HEIC. The compression savings are pretty significant. They are saying half the size of a RAW. So stay tuned. ImageMagick seems to have started on this, but it is hard to say how well it works. What we need is Photoshop to support 16-bit HEIC exports. Photos does do HEIC exports, but only at 8-bits.

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