公开(公告)号：EP1173025A1

公开(公告)日：2002-01-16

申请号：EP00202437.0

申请日：2000-07-10

Applicant: STMicroelectronics S.r.l.

Inventor： Bruna, Arcangelo ,  Mancuso, Massimo ,  Galluzzo, Agostino

IPC: H04N7/30

CPC classification number: H04N19/94 ,  H04N19/126 ,  H04N19/14 ,  H04N19/15 ,  H04N19/18 ,  H04N19/182 ,  H04N19/186 ,  H04N19/196 ,  H04N19/60

Abstract: A method (300) of compressing a digital image including a matrix of elements each one consisting of at least one component of different type representing a pixel, the method comprising the steps of splitting (340) the digital image into a plurality of blocks and calculating, for each block, a group of DCT coefficients for the components of each type, and quantizing (350a-355a) the DCT coefficients of each group using a corresponding quantization table scaled by a gain factor for achieving a target compression factor; the method also comprises the steps of further quantizing (350-355) the DCT coefficients of each group using the corresponding quantization table scaled by a pre-set factor, arranging (360) the further quantized DCT coefficients in a zig-zig vector, calculating (365-370) a basic compression factor provided by the quantization table scaled by the pre-set factor as a first function of the zigzag vector, and estimating (375) the gain factor as a second function of the basic compression factor, the second function being determined experimentally according to the target compression factor.

Abstract translation: 一种压缩数字图像的方法（300），包括由表示像素的不同类型的至少一个分量组成的元素矩阵，所述方法包括以下步骤：将数字图像分割（340）成多个块并计算 对于每个块，使用用于每种类型的分量的一组DCT系数，并且使用由用于实现目标压缩因子的增益因子缩放的对应量化表量化（350a-355a）每个组的DCT系数; 该方法还包括以下步骤：使用由预设因子缩放的相应量化表进一步量化（350-355）每个组的DCT系数，将其它量化的DCT系数排列（360）为Zig向量，计算 （365-370）由预置因子缩放的量化表提供的基本压缩因子作为之字形向量的第一函数，并且将增益因子估计为（375）作为基本压缩因子的第二函数，第二 功能根据目标压缩因子实验确定。

公开(公告)号：EP1173026B1

公开(公告)日：2008-07-30

申请号：EP00202438.8

申请日：2000-07-10

Applicant: STMicroelectronics S.r.l.

Inventor： Bruna, Arcangelo ,  Mancuso, Massimo ,  Galluzzo, Agostino

IPC: H04N7/30 ,  H04N5/232 ,  G02B7/36

CPC classification number: H04N5/2351 ,  H04N5/23212 ,  H04N19/122 ,  H04N19/126 ,  H04N19/14 ,  H04N19/149 ,  H04N19/18 ,  H04N19/186 ,  H04N19/42 ,  H04N19/60

公开(公告)号：EP1173024B1

公开(公告)日：2004-03-03

申请号：EP00202436.2

申请日：2000-07-10

Applicant: STMicroelectronics S.r.l.

Inventor： Bruna, Arcangelo ,  Mancuso, Massimo ,  Galluzzo, Agostino

IPC: H04N7/30 ,  G06T9/00

CPC classification number: H04N19/18 ,  H04N19/126 ,  H04N19/14 ,  H04N19/149 ,  H04N19/186 ,  H04N19/196 ,  H04N19/60

公开(公告)号：EP1173026A1

公开(公告)日：2002-01-16

申请号：EP00202438.8

申请日：2000-07-10

Applicant: STMicroelectronics S.r.l.

Inventor： Bruna, Arcangelo ,  Mancuso, Massimo ,  Galluzzo, Agostino

IPC: H04N7/30 ,  H04N5/232 ,  G02B7/36

CPC classification number: H04N5/2351 ,  H04N5/23212 ,  H04N19/122 ,  H04N19/126 ,  H04N19/14 ,  H04N19/149 ,  H04N19/18 ,  H04N19/186 ,  H04N19/42 ,  H04N19/60

Abstract: A method (400) of compressing a digital image including a matrix of elements each one consisting of a plurality of digital components of different type representing a pixel, the method comprising the steps of providing (410-430) an incomplete digital image wherein at least one component is missing in each element, obtaining (433-435) the digital image from the incomplete digital image, splitting (455) the digital image into blocks and calculating, for each block, a group of DCT coefficients for the components of each type, and quantizing (460-465) the DCT coefficients of each group using a corresponding quantization table scaled by a gain factor; the method further comprises the steps of determining (440) at least one energy measure of the incomplete digital image and estimating (445-450) the gain factor as a function of the at least one energy measure, the function being determined experimentally according to a target compression factor.

Abstract translation: 一种压缩数字图像的方法（400），包括由表示像素的不同类型的多个数字分量组成的元素矩阵，所述方法包括以下步骤：提供（410-430）不完整的数字图像，其中至少 在每个元素中缺少一个分量，从不完整的数字图像中获取（433-435）数字图像，将数字图像分解（455）为块，并为每个块计算每种类型的分量的一组DCT系数 并且使用由增益因子缩放的对应量化表量化（460-465）每个组的DCT系数; 该方法还包括以下步骤：确定（440）不完全数字图像的至少一个能量测量，并且根据所述至少一个能量测量值估计（445-450）所述增益因子，所述功能根据实验确定 目标压缩因子。

公开(公告)号：EP1173024A1

公开(公告)日：2002-01-16

申请号：EP00202436.2

申请日：2000-07-10

Applicant: STMicroelectronics S.r.l.

Inventor： Bruna, Arcangelo ,  Mancuso, Massimo ,  Galluzzo, Agostino

IPC: H04N7/30 ,  G06T9/00

CPC classification number: H04N19/18 ,  H04N19/126 ,  H04N19/14 ,  H04N19/149 ,  H04N19/186 ,  H04N19/196 ,  H04N19/60

Abstract: A method (400) of compressing a digital image including a matrix of elements each one consisting of a plurality of digital components of different type representing a pixel, the method comprising the steps of splitting (455) the digital image into a plurality of blocks and calculating, for each block, a group of DCT coefficients for the components of each type, and quantizing (460-465) the DCT coefficients of each block using a corresponding quantization table scaled by a gain factor for achieving a target compression factor; the method further comprises the steps of determining (440) at least one energy measure of the digital image, and estimating (441-450) the gain factor as a function of the at least one energy measure, the function being determined experimentally according to the target compression factor.

Abstract translation: 一种压缩数字图像的方法（400），包括由表示像素的不同类型的多个数字分量组成的元素矩阵，所述方法包括以下步骤：将数字图像分割成多个块， 针对每个块计算每种类型的分量的一组DCT系数，并且使用由用于实现目标压缩因子的增益因子缩放的对应量化表量化（460-465）每个块的DCT系数; 该方法还包括以下步骤：确定（440）数字图像的至少一个能量测量，以及根据所述至少一个能量测量来估计增益因子（441-450），所述功能根据实验确定 目标压缩因子。