公开(公告)号：EP2927865A1

公开(公告)日：2015-10-07

申请号：EP14305480.7

申请日：2014-04-01

申请人： Thomson Licensing ,  INRIA - Institut National de Recherche en Informatique et en Automatique

发明人： Le Pendu, Mikaël ,  Boitard, Ronan ,  Thoreau, Dominique ,  Guillemot, Christine

IPC分类号： G06T5/00 ,  G06T5/40 ,  H04N19/30

CPC分类号： H04N19/30 ,  G06T5/009 ,  G06T5/40 ,  G06T2207/20208 ,  H04N19/117 ,  H04N19/147 ,  H04N19/186

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.

摘要翻译： 要编码高动态范围（HDR）图像，HDR图像可以通过色调映射操作转换为低动态范围（LDR）图像，LDR图像可以用LDR编码器编码。 本原理在设计色调映射曲线时制定了速率失真最小化问题。 特别地，色调映射曲线被表达为要被编码的HDR图像的概率分布函数和取决于编码参数的拉格朗日乘数的函数。 在解码器中，基于指示色调映射函数的参数，可以导出逆色调映射函数，以从解码的LDR图像重建HDR图像。

公开(公告)号：EP2958329A1

公开(公告)日：2015-12-23

申请号：EP14305920.2

申请日：2014-06-16

申请人： Thomson Licensing ,  INRIA - Institut National de Recherche en Informatique et en Automatique

发明人： Le Pendu, Mikaël ,  Thoreau, Dominique ,  Alain, Martin ,  Guillemot, Christine

IPC分类号： H04N19/98 ,  H04N19/593 ,  H04N19/463 ,  H04N19/625 ,  H04N19/176 ,  H04N19/126 ,  H04N19/136

CPC分类号： H04N19/625 ,  H04N19/126 ,  H04N19/136 ,  H04N19/176 ,  H04N19/42 ,  H04N19/45 ,  H04N19/463 ,  H04N19/593 ,  H04N19/98

摘要： A method for encoding and decoding an image block, an encoder, and a decoder are provided. The method for encoding an image block comprises: determining a local dynamic range of the block; adaptively precision-extending pixel values of the block based on the local dynamic range of the block; and encoding the block with an adaptively extended precision. The method for decoding an image block comprises: determining a minimum pixel value of the block and an indicating value for indicating a precision extension factor according to precision extension information; decoding the block according to the indicating value; and de-extending precision of the decoded block based on the minimum pixel value of the block and the precision extension factor. The precision of the intermediate calculations may be improved without increasing an original intermediate bit depth used in intermediate calculations.

摘要翻译： 提供了一种用于编码和解码的图像块，在编码器和解码器方法。 用于编码图像块的方法，包括：确定性采矿块的局部动态范围; 自适应精度延伸基于所述块的局部动态范围块的像素值; 并且编码具有在自适应地扩展精度的块。 对图像块进行解码的方法，包括：确定性采矿块和指示用于指示精度扩展因子gemäß到精度扩展信息值的最小像素值; 解码所述块gemäß到指示值; 和去扩展基于该块的最小像素值和精度扩展系数的解码块的精度。 中间计算的精度可以在没有在中间计算中使用的原始中间比特深度的增加得到提高。

公开(公告)号：EP2958329B1

公开(公告)日：2018-12-05

申请号：EP14305920.2

申请日：2014-06-16

申请人： Thomson Licensing

发明人： Le Pendu, Mikaël ,  Thoreau, Dominique ,  Alain, Martin ,  Guillemot, Christine

IPC分类号： H04N19/98 ,  H04N19/593 ,  H04N19/463 ,  H04N19/625 ,  H04N19/176 ,  H04N19/126 ,  H04N19/136

CPC分类号： H04N19/625 ,  H04N19/126 ,  H04N19/136 ,  H04N19/176 ,  H04N19/42 ,  H04N19/45 ,  H04N19/463 ,  H04N19/593 ,  H04N19/98

摘要： A method for encoding and decoding an image block, an encoder, and a decoder are provided. The method for encoding an image block comprises: determining a local dynamic range of the block; adaptively precision-extending pixel values of the block based on the local dynamic range of the block; and encoding the block with an adaptively extended precision. The method for decoding an image block comprises: determining a minimum pixel value of the block and an indicating value for indicating a precision extension factor according to precision extension information; decoding the block according to the indicating value; and de-extending precision of the decoded block based on the minimum pixel value of the block and the precision extension factor. The precision of the intermediate calculations may be improved without increasing an original intermediate bit depth used in intermediate calculations.

公开(公告)号：EP3096518A1

公开(公告)日：2016-11-23

申请号：EP15305760.9

申请日：2015-05-20

申请人： Thomson Licensing

发明人： Le Pendu, Mikaël ,  Alain, Martin ,  Thoreau, Dominique ,  Guillemot, Christine

IPC分类号： H04N19/176 ,  H04N19/102 ,  H04N19/136

CPC分类号： H04N19/33 ,  H04N19/102 ,  H04N19/136 ,  H04N19/176

摘要： The present principles provide a method and an encoder for encoding an image frame. The method includes generating, with a processor, for each block in the image frame a prediction block based on at least a prediction method; generating a scaling factor and an offset for adjusting the prediction block; and transforming the prediction block into an adjusted prediction block based on the scaling factor and the offset. The encoder includes a processor configured to, for each block in the image frame, generate a prediction block based on at least a prediction method and generate a scaling factor and an offset for adjusting the prediction block and to transform the prediction block into an adjusted prediction block based on the scaling factor and the offset. The scaling factor and offset minimize error between the block and the adjusted prediction block.

摘要翻译： 本原理提供了一种用于编码图像帧的方法和编码器。 该方法包括：基于至少预测方法，利用处理器为图像帧中的每个块生成预测块; 生成用于调整预测块的缩放因子和偏移量; 以及基于所述缩放因子和所述偏移将所述预测块变换为调整后的预测块。 所述编码器包括：处理器，被配置为，对于所述图像帧中的每个块，至少基于预测方法生成预测块，并生成用于调整所述预测块的缩放因子和偏移量，并将所述预测块变换为调整预测 基于缩放因子和偏移量的块。 缩放因子和偏移最小化块和调整后的预测块之间的误差。

公开(公告)号：EP3032830A1

公开(公告)日：2016-06-15

申请号：EP14306968.0

申请日：2014-12-08

申请人： Thomson Licensing

发明人： Thoreau, Dominique ,  Alain, Martin ,  Le Pendu, Mikaël ,  Turkan, Mehmet

IPC分类号： H04N19/11 ,  H04N19/14 ,  H04N19/176 ,  H04N19/463

CPC分类号： H04N19/11 ,  H04N19/14 ,  H04N19/159 ,  H04N19/176 ,  H04N19/44 ,  H04N19/463 ,  H04N19/593

摘要： A method of encoding a video image includes, for each one of blocks of the video image, calculating virtual gradient values in the block depending on neighboring gradient values computed in a causal neighborhood of the block and acquiring one prediction direction or non-directional intra prediction mode based on the virtual gradient values; and determining a coding mode by comparing different predictions for the block , acquiring a predicted block by applying the determined "coding mode", acquiring a residual error between the predicted block and the current block and encoding a difference between the determined coding mode and the prediction direction or non-directional intra prediction mode. The calculating includes, for each prediction direction, propagating the neighboung gradient values along the prediction direction to estimate the virtual gradient values in the block.

摘要翻译： 编码视频图像的方法包括：对于视频图像的每个块，根据在块的因果关联中计算的相邻梯度值来计算块中的虚拟梯度值，并获取一个预测方向或非定向帧内预测 基于虚拟梯度值的模式; 以及通过比较块的不同预测来确定编码模式，通过应用所确定的“编码模式”获取预测块，获取预测块与当前块之间的残差，并对所确定的编码模式与预测之间的差进行编码 方向或非定向帧内预测模式。 对于每个预测方向，计算包括沿预测方向传播邻近梯度值以估计块中的虚拟梯度值。