Some analysis of HD Photo

Some published tests

Size comparisons for lossless formats

Here are some comparisons I've done for a Canon IDs II raw image (4992 x 3328):

CR2: 17.6 MB
DNG: 14.8 MB
Linear DNG, compressed: 60.7 MB

After an 8-bit conversion by ACR:

HD Photo lossless: 14.3 MB
JPEG2000 lossless: 12.5 MB
8-bit PSD: 43.3 MB
8-bit TIFF LZW: 17.7 MB
8-bit TIFF uncompressed: 48.7 MB

8-bit TIFF > ACR 4.1 > Linear DNG, compressed: 64.2 MB
8-bit TIFF > DNG Converter 4.1 > Linear DNG, compressed: 20.2 MB

After a 16-bit conversion by ACR:

HD Photo lossless: 54.8 MB
JPEG2000 lossless: 51.6 MB
16-bit PSD: 97.3 MB
16-bit TIFF LZW: 108.9 MB
16-bit TIFF uncompressed: 97.3 MB

16-bit TIFF > ACR 4.1 > Linear DNG, compressed: 71.2 MB

Comparison of JPEG and HD Photo lossless compressions

From GordonBGood: "... a HDP file for a full 16 bit per channel linear raw is only 17.8 MBytes as compared to the DNG 16 bit linear raw file of 19.2 MBytes for a win by HDP. This indicates that Microsoft's claim of HDP being more compression efficient than Lossless JPEG is also true, although perhaps not to the halfing of file size that is claimed generally".