Backwards Compatible Extended Image Format

摘要

Techniques are provided for encoding an extended image such that it is backwards compatible with existing decoding devices. An extended image format is defined such that the extended image format is consistent with an existing image format over the full range of the existing image format. Because the extended image format is consistent with the existing image format over the full range of the existing image format, additional image information that is included in an extended image can be extracted from the extended image. A base version of an image (expressed using the existing image format) may be encoded in a payload portion and the extracted additional information may be stored in a metadata portion of a widely supported image file format.

主权项

1. A non-transitory program storage device, readable by a processing unit and comprising instructions stored thereon to cause one or more processors to:
obtain a first image expressed in a first image format, each element in the first image defined by one or more reference values in a first range of values; obtain a second image that corresponds to the first image and is expressed in a second image format, each element in the second image defined by one or more reference values in a second range of values, wherein the first range of values is a proper subset of the second range of values; obtain a delta image based, at least in part, on the first and second images; encode the first image in a payload portion of an image file; and encode the delta image in a metadata portion of the image file.