摘要:
To encode High Dynamic Range (HDR) images, the HDR images can be converted to Low Dynamic Range (LDR) images through tone mapping operation, and the LDR images can be encoded with an LDR encoder. The present principles formulates a rate distortion minimization problem when designing the tone mapping curve. In particular, the tone mapping curve is formulated as a function of the probability distribution function of the HDR images to be encoded and a Lagrangian multiplier that depends on encoding parameters. At the decoder, based on the parameters indicative of the tone mapping function, an inverse tone mapping function can be derived to reconstruct HDR images from decoded LDR images.
摘要:
A method and apparatus for dynamic range expansion of an LDR video sequence are suggested. The suggested method comprises the steps of: acquiring the LDR video sequence and at least one HDR panoramas concurrently, determining a dynamic range expansion operator based on the LDR video sequence and the HDR panoramas, and applying the determined dynamic range expansion operator on the LDR video sequence.
摘要:
The invention relates to a method for processing a video sequence formed by at least two video images, said method comprising: - obtaining (13) said at least two video images using a first capture module (120, 41) with a first field of view (C1), each video image representing a same scene captured at differents instants or from different points of view,
wherein said method comprises: - determining (15) luminance information from at least one overall image obtained by a second capture module (121, 42) with a second field of view greater than said first field of view, said overall image representing the scene captured at different instants or from different points of view;, - down-converting (16) a dynamic range of said video images taking into account said luminance information.
摘要:
The invention relates to a method processing a video sequence, said method comprising a step of obtaining at least one image using a first capture module, said at least one image representing a scene with a first capture angle, said at least one image being called video image. According to the invention, said method comprises the following steps: - obtaining, by using a second capture module different from said first capture module, metadata corresponding to at least one image representing said scene with a second capture angle strictly greater than said first capture angle, said at least one image being called overall image, said overall image comprising said video image, - determining luminance information from said metadata corresponding to said overall image, - conversion of a dynamic range of said video image taking into account of said luminance information.
摘要:
The present disclosure generally relates to a method and device for quantizing a picture comprising a luminance component and two color components representing the chrominance of the picture, the method is characterized in that it comprises adjusting, before quantizing, each color component of the picture according to a scaling factor defined from the luminance component of the picture.
摘要:
A method and apparatus for dynamic range expansion of an LDR video sequence are suggested. The suggested method comprises the steps of: acquiring the LDR video sequence and at least one HDR panoramas concurrently, an image in said HDR encompassing a wider field of view than an image in said LDR; determining a dynamic range expansion operator based on the LDR video sequence and the HDR panoramas; and applying the determined dynamic range expansion operator on the LDR video sequence.
摘要:
A method (350) includes: applying (S360) inverse tone mapping operations to a block (b b ) of a first layer ( l b ) and to a prediction block (b b ) of the block ( b b ) of the first layer ( l b ) , respectively, computing (S365) a residual prediction error r b e in a second layer ( l e ), and computing (S370) a prediction ( p e ) of a block of the second layer (l e ).
摘要:
The invention relates to a method for converting the dynamic range of at least one image of a group of images (11), said group of images representing at least one part of a scene. According to the invention, said method comprises the following steps, all implemented using a processor: - generating (12) at least one piece of information representative of said scene using at least one element belonging to the group comprising: o said group of images (11) and/or, o a synthetic result delivered by a 3D modelling (120) of said scene,
- tone-mapping (13) said at least one image using said at least one piece of information representative of said scene.
摘要:
A method and device for processing LDR images of a video sequence to improve image quality. The method comprises temporally decomposing successive HDR frames of a video sequence and the corresponding LDR frames and performing a comparison between the HDR and LDR frequency sub-bands. A current LDR image can then be modified on the basis of a comparison between the frequency sub-bands.