Supporting multiple target display types
A sequence of base layer images for a base reference image display and a set of one or more sequences of beta scale maps corresponding to one or more non-base reference image displays are generated. A subset of one or more sequences of beta scale maps is determined in the set of one or more sequences of beta scale maps based at least in part on display capabilities of a target image display. The sequence of base layer images, along with the subset of one or more sequences of beta scale maps, is encoded into a video signal to cause a recipient device of the video signal to generate a sequence of display images from the sequence of base layer images and the subset of one or more sequences of beta scale maps for rendering on the image display.
1 . A method comprising:
generating a sequence of base layer images for a base reference image display and a set of one or more sequences of beta scale maps corresponding to one or more non-base reference image displays;
determining a subset of one or more sequences of beta scale maps in the set of one or more sequences of beta scale maps based at least in part on display capabilities of a target image display;
encoding the sequence of base layer images, along with the subset of one or more sequences of beta scale maps, into a video signal to cause a recipient device of the video signal to generate a sequence of display images, from the sequence of base layer images and the subset of one or more sequences of beta scale maps, for rendering on the target image display,
wherein the beta scale map corresponds to an image comprising beta scaling data for a corresponding base layer image of a base reference color grade optimized for image rendering operations with the base reference image display,
wherein the subset of the one or more sequences of the beta scale maps are target-display specific sequences of the beta scale maps for the target image display.
2 . The method of claim 1 , wherein the sequence of base layer images is of a first dynamic range; wherein the subset of one or more sequences of beta scale maps includes a sequence of beta scale maps used to apply scaling operations on the sequence of base layer images to generate a sequence of non-base layer images of a second dynamic range; wherein the second dynamic range is different from the first dynamic range.
3 . The method of claim 2 , wherein the subset of one or more sequences of beta scale maps includes a second sequence of beta scale maps used to apply second scaling operations on the sequence of base layer images to generate a second sequence of non-base layer images of a third dynamic range; wherein the third dynamic range is different from the first dynamic range and the second dynamic range.
4 . The method of claim 1 , wherein each display image in the sequence of display images represents one of: an image of a standard dynamic range, an image of high dynamic range, an image of an intermediate dynamic range between the standard dynamic range and the high dynamic range, an image of a dynamic range lower than the standard dynamic range, an image of a dynamic range higher than the high dynamic range, or a display mapped image that is optimized for rendering on the target image display.
5 . The method of claim 1 , wherein the subset of one or more sequences of beta scale maps is selected from a plurality of sequences of beta scale maps based at least in part on comparing the display capabilities of the target image display with corresponding display capabilities of the one or more non-base reference image displays.
6 . The method of claim 1 , wherein the scaling operations include one or more of: simple scaling with scaling factors, or applying one or more codeword mapping relationships to map codewords of the sequence of base layer images to generate corresponding codeword of a corresponding sequence of beta scaled images.
7 . The method of claim 1 , wherein the scaling operations are performed in place of one or more of: global tone mapping, local tone mapping, display mapping operations, color space conversion, linear mapping, or non-linear mapping.
8 . The method of claim 1 , wherein the sequence of base layer images is encoded in a base layer of the video signal.
9 . The method of claim 1 , wherein a common sequence of source images is used to generate both the sequence of base layer images for the base reference image display and the set of one or more sequences of beta scale maps corresponding to the one or more non-base reference image displays.
10 . A method comprising:
decoding, from a video signal, a sequence of base layer images, the sequence of base layer images having been optimized for image rendering on a base reference image display;
decoding, from the video signal, a subset of one or more sequences of beta scale maps, the subset of one or more sequences of beta scale maps having been determined from a set of one or more sequences of beta scale maps corresponding to one or more non-base reference image displays based on display capabilities of a target image display;
causing a sequence of display images from the sequence of base layer images and the subset of one or more sequences of beta scale maps, to be rendered on the target image display,
wherein the beta scale map corresponds to an image comprising beta scaling data for a corresponding base layer image of a base reference color grade optimized for image rendering operations with the base reference image display,
wherein the subset of the one or more sequences of the beta scale maps are target-display specific sequences of the beta scale maps for the target image display.
11 . The method of claim 10 , where a subset of one or more sequences of beta scale maps include one of: a single sequence of beta scale maps, or two sequences of beta scale maps.
12 . The method of claim 10 , wherein the sequence of display images is generated from a sequence of extrapolated beta scale maps in combination with the sequence of base layer images; wherein the sequence of extrapolated beta scale maps is generated from the subset of one or more sequences of beta scale maps through extrapolation operations using operational parameters determined based at least in part on display capabilities of the one or more non-base reference image displays and the display capabilities of the target image display.
13 . The method of claim 10 , wherein the sequence of display images is generated from a sequence of interpolated beta scale maps in combination with the sequence of base layer images; wherein the sequence of interpolated beta scale maps is generated from the subset of one or more sequences of beta scale maps through interpolation operations using operational parameters determined based at least in part on display capabilities of the one or more non-base reference image displays and the display capabilities of the target image display.
14 . An apparatus performing the method recited in claim 1 .
15 . A non-transitory computer readable storage medium, storing software instructions, which when executed by one or more processors cause performance of the method recited in claim 1 .
16 . The method of claim 1 , wherein each sequence of beta scale maps in the one or more sequences of beta scale maps includes respective operational parameters for scaling operations to be performed on the sequence of base layer images to generate a respective sequence of non-base layer images for a respective non-base reference image display in the one or more non-base reference image displays.
17 . The method of claim 10 , wherein each sequence of beta scale maps in the one or more sequences of beta scale maps includes respective operational parameters for scaling operations to be performed on the sequence of base layer images to generate a respective sequence of non-base layer images for a respective non-base reference image display in the one or more non-base reference image displays.