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JPEG XR (abbr. for JPEG extended range ) is a first time in 2009 published standard for image compression which is based on technologies that were originally developed by Microsoft under the name HD Photo (formerly Windows Media Photo ) developed and patented. JPEG XR supports both lossy and lossless compression, a variety of color spaces and coding techniques, and alpha channels and additional metadata. All data are combined in a TIFF -like container.


After digital photography beginning of the millennium became increasingly a matter of course, reinforced the need for an appropriate graphic format. The most common by far the format is JFIF (JPEG), technically advanced solutions, such as JPEG 2000 could be in the market so far not prevail. Windows Media Photo was first presented in May 2006 at the conference organized by Microsoft WinHEC.

The format was finally introduced with Windows Vista. In November 2006, the format was renamed HD Photo. In March 2007 it was announced that Microsoft plans to have HD Photo standardize. By end of July 2007 gave Microsoft and the Joint Photographic Experts Group to initiate the standardization process under the name JPEG XR known. Mid-March 2009 JPEG XR was approved as ITU- T Recommendation T.832, standardized in June of the same year as ISO / IEC 29199-2.


JPEG XR based on a block - codec and the Hadamard transform. Here, the image is first divided main blocks in 4x4 pixels and this is correlated with the lossless Hadamard transform, integer transform is referred to in this context as "photo core transform " ( PCT), and similar to the Discrete used in JPEG cosine (DCT ) works. Optionally, a second 4x4 transform to downstream, which operates on blocks, which are shifted by two pixels in the diagonal. This " Photo Overlap Transformation" (POT ) avoids blocking artifacts. The output of this first filtering are 15 high-pass and low pass per block.

The low-pass component of 16 blocks is again filtered using the same procedure, again, optionally, a further POT filtering can be connected here as well. This produces per 16 blocks 15 band pass and low pass. This arrangement of 16 blocks is also called macroblock.

The downstream there is a quantization, but all high-pass, band-pass and all of the low-pass each use only one common quantizer.

The entropy coding is done by an adaptive Huffman coder.

The mean square error or the PSNR XR images of JPEG compression is the same rate as between JPEG 2000 and JPEG. The complexity of JPEG XR is slightly higher than that of JPEG, however, significantly lower than that of JPEG 2000.

Application Support

JPEG XR files are supported, among others, the following applications or there are plug-ins from third-party manufacturers submit the JPEG XR support for these applications.


The HD Photo format, and thus also of the JPEG XR standard include Microsoft patented techniques. In an interview in January 2007, said a Microsoft representative that the specification of the HD Photo format to Microsoft Open Specification Promise will be, which will lead to the widespread use and standardization of the format. This means that Microsoft offers the free specification and will refrain from actions for patent infringement. Since August 2010, JPEG XR is listed in the list of areas covered by the Community Promise specifications.

In April 2013, Microsoft released an open-source JPEG XR library under the BSD license, which is also compatible with software as opposed to the " HD Photo Device Porting Kit " under one of the popular open source licenses such as the GNU General Public License is available.