Backwards-Compatible Delivery of Digital Cinema Content with Extended Dynamic Range
AssigneeDolby Laboratories Licensing Corporation
InventorsWalter C. GISH, Christopher J. VOGT
Life of this patent
Estimating the term…
Abstract
A digital cinema signal is encoded to produce a resulting coded digital cinema bitstream. Decoding the resulting coded digital cinema bitstream allows backwards-compatible delivery of digital cinema content. A digital image or video signal is preprocessed to produce two normalized digital image or video signals of differing quality levels and forward and inverse mapping parameters, which relate the normalized digital image or video signals. The preprocessing can be used prior to the encoding of a digital cinema signal to enable backwards-compatible delivery of digital cinema content.
Claims20
A method of decoding a coded digital bitstream (255), wherein the coded digital bitstream (255) comprises a coded digital image (105A, 105B) and mapping metadata (125A, 125B), the method comprising:
- decoding the coded digital bitstream with a decoder (110A, 110B) to generate a first normalized digital image (115A, 115B) with a first dynamic range;
- and
- applying (120) the mapping metadata to the first normalized digital image to generate a second normalized digital cinema image (130A, 130B) with a second dynamic range, wherein the mapping metadata comprise an invertible mapping between the first and the second normalized digital images, wherein the invertible mapping comprises an invertible nonlinear transformation and an invertible matrix transformation.
A method to generate a coded bitstream (255), wherein the coded digital bitstream comprises a coded digital image (230, 235) and mapping metadata (240, 245), the method comprising:
- receiving an input image (205);
- generating (210) using the input image a first digital image (215) having a first dynamic range;
- generating (210) using the input image a second digital image (220) having a second dynamic range, the second dynamic range being higher than the first dynamic range;
- producing a first normalized digital image (230) and a second normalized digital image (235) by pre-processing the first digital image and the second digital image, wherein the first normalized digital image and the second normalized image are inter-related via an invertible mapping that comprises an invertible nonlinear transformation and an invertible linear matrix transformation;
- and
- generating the coded bitstream (255) based on the first or second normalized digital image and metadata related to the invertible mapping.
Dependencies are inferred from the claim text.