公开(公告)号：US20150350688A1

公开(公告)日：2015-12-03

申请号：US14696032

申请日：2015-04-24

Applicant: Apple Inc.

Inventor： Jian Lou ,  Xiaojin Shi

IPC: H04N19/895 ,  H04N19/18 ,  H04N19/172 ,  H04N19/103 ,  H04N19/159

CPC classification number: H04N19/103 ,  H04N19/154

Abstract: Methods and systems provide video compression to reduce a “flashing” effect, typically caused by skipping coding or allocating a low number of bits in coding relatively low complexity portions of frames. In an embodiment, if at least a portion of a sequence of frames is of relatively low complexity, a history of coding blocks may be considered to determine whether to skip coding. In an embodiment, a number of coding bits allocated to a block may be increased based on a history of the coding block and a likelihood of flashing. The history of coding of each pixel block may be a basis for forcing a higher quantization parameter coding of pixel block(s) of high motion portions such that a low bit rate is maintained despite a larger number of bits being allocated to flashing-susceptible blocks. In another embodiment, force coding of relatively low complexity portions may be delayed by a number of frames.

Abstract translation: 方法和系统提供视频压缩以减少“闪烁”效应，通常是由于在编码相对低复杂度的帧部分中编码或分配低数量的比特来引起的。 在一个实施例中，如果帧序列的至少一部分具有相对低的复杂度，则可以考虑编码块的历史以确定是否跳过编码。 在一个实施例中，可以基于编码块的历史和闪烁的可能性来增加分配给块的编码比特数。 每个像素块的编码历史可以是用于强制高运动部分的像素块的较高量化参数编码的基础，使得尽管将较大数量的比特分配给闪烁敏感块，维持低比特率 。 在另一个实施例中，相对低复杂度部分的强制编码可能被延迟多个帧。

公开(公告)号：US20150341659A1

公开(公告)日：2015-11-26

申请号：US14696162

申请日：2015-04-24

Applicant: Apple Inc.

Inventor： Jian Lou ,  Xiaojin Shi ,  Jian Zhou

IPC: H04N19/577

CPC classification number: H04N19/577 ,  H04N19/105 ,  H04N19/53

Abstract: A pipelined video coding system may include a motion estimation stage and an encoding stage. The motion estimation stage may operate on an input frame of video data in a first stage of operation and may generate estimates of motion and other statistical analyses. The encoding stage may operate on the input frame of video data in a second stage of operation later than the first stage. The encoding stage may perform predictive coding using coding parameters that are selected, at least in part, from the estimated motion and statistical analysis generated by the motion estimator. Because the motion estimation is performed at a processing stage that precedes the encoding, a greater amount of processing time may be devoted to such processes than in systems that performed both operations in a single processing stage.

Abstract translation: 流水线视频编码系统可以包括运动估计级和编码级。 运动估计阶段可以在第一操作阶段中对视频数据的输入帧进行操作，并且可以产生运动和其他统计分析的估计。 编码级可以在晚于第一级的第二操作阶段中对视频数据的输入帧进行操作。 编码阶段可以使用至少部分地由运动估计器生成的估计运动和统计分析来选择的编码参数来执行预测编码。 因为在编码之前的处理阶段执行运动估计，所以与在单个处理阶段中执行两个操作的系统相比，可以将更多的处理时间用于这样的处理。

公开(公告)号：US20160353107A1

公开(公告)日：2016-12-01

申请号：US14721903

申请日：2015-05-26

Applicant: Apple Inc.

Inventor： Jian Lou ,  Congxia Dai ,  Hao Pan ,  Xiaohua Yang

IPC: H04N19/126 ,  H04N19/184 ,  H04N19/172 ,  H04N19/182 ,  H04N19/176

CPC classification number: H04N19/176 ,  H04N19/124 ,  H04N19/136 ,  H04N19/167 ,  H04N19/182

Abstract: Methods and systems provide an adaptive quantization parameter (QP) modulation scheme for video coding and compression that is sensitive to user visual perception. In an embodiment, the method includes detecting an eye sensitive region, where a region is considered sensitive based on a noticeability of a visual effect. The method includes estimating encoding parameters for image content in the detected eye sensitive region. The method further includes encoding the detected eye sensitive region with the estimated encoding parameters. The estimating the encoding parameters may be based on, among other things, a variance, a motion vector, a DC value, an edge value, and external information such as a user command or screen content. The encoding may include storing an average or maximum sum of square differences (SSD) value for a detected eye sensitive area and adjusting a QP value based on a comparison of the SSD value to generated threshold values.

Abstract translation: 方法和系统为视频编码和压缩提供了一种对用户视觉感知敏感的自适应量化参数（QP）调制方案。 在一个实施例中，该方法包括基于视觉效果的显着性检测区域被认为是敏感的眼睛敏感区域。 该方法包括估计检测到的眼睛敏感区域中的图像内容的编码参数。 该方法还包括用所估计的编码参数来编码检测到的眼睛敏感区域。 估计编码参数可以基于方差，运动矢量，DC值，边缘值以及诸如用户命令或屏幕内容的外部信息。 编码可以包括存储检测到的眼睛敏感区域的平均差异（SSD）值的平均或最大和，并且基于SSD值与生成的阈值的比较来调整QP值。