公开(公告)号：US20170318295A1

公开(公告)日：2017-11-02

申请号：US15648329

申请日：2017-07-12

Applicant: Apple Inc.

Inventor： Thomas Pun ,  Roger Kumar ,  Xiaochun Nie ,  Hsi-Jung Wu

IPC: H04N19/126 ,  H04N19/61 ,  H04N19/196 ,  H04N19/146 ,  H04N19/176 ,  H04N19/149 ,  H04N19/625

CPC classification number: H04N19/126 ,  H04N19/146 ,  H04N19/149 ,  H04N19/176 ,  H04N19/196 ,  H04N19/197 ,  H04N19/61 ,  H04N19/625

Abstract: Method For Implementing A Quantizer In A Multimedia Compression And Encoding System is disclosed. In the Quantizer system of the present invention, several new quantization ideas are disclosed. In one embodiment, adjacent macroblocks are grouped together into macroblock groups. The macroblock groups are then assigned a common quantizer value. The common quantizer value may be selected based upon how the macroblocks are encoded, the type of macroblocks within the macroblock group (intra-blocks or inter-blocks), the history of the motion vectors associated with the macroblocks in the macroblock group, the residuals of the macroblocks in the macroblock group, and the energy of the macroblocks in the macroblock group. The quantizer value may be adjusted in a manner that is dependent on the current quantizer value. Specifically, if the quantizer value is at the low end of the quantizer scale, then only small adjustments are made. If the quantizer value is at the high end then larger adjustments may be made to the quantizer. Finally, in one embodiment, the quantizer is implemented along with an inverse quantizer for efficient operation.

公开(公告)号：US09706201B2

公开(公告)日：2017-07-11

申请号：US14723264

申请日：2015-05-27

Applicant: Apple Inc.

Inventor： Thomas Pun ,  Paul Chang ,  Hsi-Jung Wu

IPC: H04N19/105 ,  H04N19/182 ,  H04N19/52 ,  H04N19/176 ,  H04N19/46 ,  H04N19/134 ,  H04N19/102 ,  H04N19/61 ,  H04N19/157 ,  H04N19/44 ,  H04N19/436

CPC classification number: H04N19/105 ,  H04N19/102 ,  H04N19/134 ,  H04N19/157 ,  H04N19/176 ,  H04N19/182 ,  H04N19/436 ,  H04N19/44 ,  H04N19/46 ,  H04N19/52 ,  H04N19/61

Abstract: A method for decoding a compressed video data sequence containing one or more coded pixel blocks. The compressed video sequence is buffered. Prediction information for each of the coded pixel blocks is reviewed. One or more groups of coded pixel blocks are formed based on the reviewed prediction information such that the coded pixel blocks within a given group have similar prediction dependencies and/or at least do not depend on a reconstructed pixel within a group of received pixel blocks to enable parallel decoding. The formed groups are scheduled for processing and subsequently decoded to produce a decoded video data sequence.

公开(公告)号：US20150003515A1

公开(公告)日：2015-01-01

申请号：US14479014

申请日：2014-09-05

Applicant: Apple Inc.

Inventor： Jim Normile ,  Thomas Pun ,  Xiaojin Shi ,  Xin Tong ,  Hsi-Jung Wu

IPC: H04N19/154 ,  H04N19/164

CPC classification number: H04N19/154 ,  H04N19/156 ,  H04N19/164

Abstract: Techniques for encoding data based at least in part upon an awareness of the decoding complexity of the encoded data and the ability of a target decoder to decode the encoded data are disclosed. In some embodiments, a set of data is encoded based at least in part upon a state of a target decoder to which the encoded set of data is to be provided. In some embodiments, a set of data is encoded based at least in part upon the states of multiple decoders to which the encoded set of data is to be provided.