Abstract: A method comprising: obtaining an histogram of a current SDR picture, the histogram comprising bins, a bin associating a sample value to a number of occurrences of the sample value in the current SDR picture; determining a current state value representative of the current SDR picture from at least one most representative bin of the histogram, the most representative bin being the bin of the histogram representing the highest number of samples of the current SDR picture; identifying a profile in a set of a plurality of profiles corresponding to the determined current state value, each profile of the plurality being associated to an expansion function; and, applying an inverse tone mapping to the current SDR picture using the expansion function associated with the identified profile to obtain a HDR picture.

Abstract: A method comprising: obtaining standard dynamic range data; obtaining (601) information representative of an inverse tone mapping process adapted to generate high dynamic range data from the standard dynamic range data and inserting the information in metadata; providing video data representative of the standard dynamic range data (600) along with the metadata (602).

Abstract: A method comprising: obtaining (401) high dynamic range data; computing (402, 403) a first tone mapping curve from the high dynamic range data corresponding to low high dynamic range values of a combined tone mapping curve, the first tone mapping curve ending by a point, called first point, with an abscissa representative of a high dynamic range diffuse white and an ordinate representative of a standard dynamic range diffuse white, the combined tone mapping curve allowing obtaining standard dynamic range data from the high dynamic range data; and completing (404) the combined tone mapping curve with a second tone mapping curve for high standard dynamic range starting from the first point.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: decoding (10) at least one stream S_diff into decoded data and into one information for identifying a reconstructed reference picture in a decoder picture buffer; reconstructing (12) a special reference picture from at least the identified reconstructed reference picture and from the decoded data; reconstructing (16) the picture block from at least the special reference picture, wherein the at least the special reference picture is not displayed.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: —decoding (10) at least one stream S_diff into decoded data and into one information for identifying a re-constructed reference picture in a decoder picture buffer; —reconstructing (12) a special reference picture from at least the identified reconstructed reference picture and from the decoded data; —reconstructing (16) the picture block from at least the special reference picture, wherein the at least the special reference picture is not displayed.

Abstract: Different implementations are described, particularly implementations for processing a medium dynamic range video signal are presented. In a method for processing such a video signal a medium dynamic range video signal and associated metadata are received, wherein the metadata include data representative of a peak luminance value of the medium dynamic range video signal. In addition, data representative of a peak luminance value of a presentation display are received. It is determined whether the peak luminance value of the medium dynamic range video signal is greater or lower than the peak luminance value of the presentation display. A processor is configured based on the determination, wherein the processor has a first mode to reconstruct a high dynamic range video signal based on a received standard dynamic range video signal and associated metadata, and a second mode to optimize a received high dynamic range video signal for the rendering device.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises:—decoding (10) at least one stream S_diff into decoded data and into one information for identifying a re-constructed reference picture in a decoder picture buffer;—reconstructing (12) a special reference picture from at least the identified reconstructed reference picture and from the decoded data;—reconstructing (16) the picture block from at least the special reference picture, wherein the at least the special reference picture is not displayed.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: —decoding (10) at least one stream S_diff into decoded data and into one information for identifying a reconstructed reference picture in a decoder picture buffer; —reconstructing (12) a special reference picture from at least the identified reconstructed reference picture and from the decoded data; —reconstructing (16) the picture block from at least the special reference picture, wherein the at least the special reference picture is not displayed.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: —decoding (10) at least one stream S_diff into decoded data and into one information for identifying a reconstructed reference picture in a decoder picture buffer; —reconstructing (12) a special reference picture from at least the identified reconstructed reference picture and from the decoded data; —reconstructing (16) the picture block from at least the special reference picture, wherein the at least the special reference picture is not displayed.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: reconstructing reference picture from another reference picture of a decoder picture buffer of a first layer of a multi-layered stream and from data decoded from a second layer of said multi-layered stream and storing said reference picture in a decoder picture buffer of said second layer, wherein said reference picture is indicated as not to be displayed; decoding a flag indicating that a subsequently decoded picture of the second layer is not using any inter-layer prediction; and reconstructing a picture block of said subsequently decoded picture at least from said reference picture.

Abstract: Different implementations are described, particularly implementations for processing a medium dynamic range video signal are presented. In a method for processing such a video signal a medium dynamic range video signal and associated metadata are received, wherein the metadata include data representative of a peak luminance value of the medium dynamic range video signal. In addition, data representative of a peak luminance value of a presentation display are received. It is determined whether the peak luminance value of the medium dynamic range video signal is greater or lower than the peak luminance value of the presentation display. A processor is configured based on the determination, wherein the processor has a first mode to reconstruct a high dynamic range video signal based on a received standard dynamic range video signal and associated metadata, and a second mode to optimize a received high dynamic range video signal for the rendering device.

Abstract: A medium dynamic range video signal and associated metadata are received, wherein the metadata include data representative of a peak luminance value of the signal. The medium dynamic range video signal is processed in a first mode to reconstruct a high dynamic range video signal based on a received standard dynamic range video signal and associated metadata if the peak luminance value of the medium dynamic range video signal is smaller than the peak luminance value of a presentation display, and in a second mode to optimize a received high dynamic range video signal for a rendering device if the peak luminance value of the medium dynamic range video signal is greater than the peak luminance value of the presentation display.

Abstract: A medium dynamic range video signal and associated metadata are received, wherein the metadata include data representative of a peak luminance value of the signal. The medium dynamic range video signal is processed in a first mode to reconstruct a high dynamic range video signal based on a received standard dynamic range video signal and associated metadata if the peak luminance value of the medium dynamic range video signal is smaller than the peak luminance value of a presentation display, and in a second mode to optimize a received high dynamic range video signal for a rendering device if the peak luminance value of the medium dynamic range video signal is greater than the peak luminance value of the presentation display.

Abstract: A system and methods is provided for performing, by a processor, an initial tone mapping function on a first image to produce a second image. The first and second images are of different dynamic ranges. The method also includes applying, by the processor, a second tone mapping function to the second image when it contains any saturated portions. The second tone mapping function lowers luminance by a first fraction. The overall luminance of the second image is also determined and a fine tuning filter is applied when at least portions of said second image contain areas darker than an amount.

Abstract: A method and device of encoding both a HDR picture (IHDR) and a first SDR picture (ISDR1) obtained from said HDR picture, in at least one bitstream (F1, F2, F3, F4). The method comprises: —obtaining (210) a second SDR picture (ISDR2) by tone-mapping the HDR picture (IHDR); —obtaining (230) a color mapping function (CMF) that allows the mapping of the colors of the second SDR picture (ISDR2) onto the colors of a third SDR picture (ISDR3) obtained (220) from the first SDR picture (ISDR1); —encoding (240), in a bitstream, an information (INF) representative of the color mapping function; and —encoding (260), in a bitstream, a fourth SDR picture (ISDR4) obtained (250) from the first SDR picture (ISDR1). The present disclosure further relates to a method and device of decoding.

Abstract: The invention concerns scaling color difference components prior to encoding in order to extend the dynamic range. In one embodiment the color difference components are encoded prior to quantization. In another embodiment the color difference components are encoded after quantization. A decoder is configured to process data representative of the gain factor for a decoding process.

Abstract: The present disclosure generally relates to a method and device for obtaining three color difference components from three components C1, C2 and C3 representing colors picture data in an input color space, a first of said color difference components being defined from the component C1, a second of said color difference components being defined from the first color difference component and the component C2, and a third of said color difference components being defined from the first color difference component and the component C3. The method is characterized in that it further comprises: —obtaining a first component by applying a process to the component C1; —obtaining said first color difference component by applying the inverse process to the first component.

Abstract: A method for decoding a picture block is disclosed. The decoding method comprises: decoding decoded data, and information for identifying a reconstructed reference picture in a decoder picture buffer; reconstructing another reference picture from the identified reconstructed reference picture identified by the information and from the decoded data; replacing in the decoder picture buffer the reconstructed reference picture identified by the information with the another reference picture; and reconstructing the picture block from the another reference picture.

Abstract: A method for encoding a plenoptic image divided into blocks is disclosed. The method comprises: —encoding (S120) a block in a central region of the plenoptic image, called central block, without spatial prediction; and —predictively encoding (S130) blocks immediately surrounding said central block by spatially interleaving spatial unidirectional prediction and spatial bi-directional prediction.

Abstract: Encoding or decoding a stack of images of a same scene focused at different focalization distances from one image to another can involve encoding or decoding information representing an image of the stack of images, where the image meets an image sharpness criterion, reconstructing the image into a reconstructed image, and encoding or decoding at least one other image of the stack of images by prediction from at least the reconstructed image.