公开(公告)号：US10382516B2

公开(公告)日：2019-08-13

申请号：US15590442

申请日：2017-05-09

Applicant: Apple Inc.

Inventor： David Makower ,  Paul A. Francis ,  Yu Chieh Lin

IPC: H04L29/06 ,  H04N19/146 ,  H04N19/172 ,  H04N19/119

Abstract: Techniques are disclosed for estimating a source resolution of image data presented to a system. According to these techniques, input image data may be converted to a domain of frequency coefficients. Each coefficient may represent content of the input image along a respective pair of frequencies extending in two dimensions. For each set of frequency coefficients having a common frequency in one of the dimensions, zero crossings of coefficient values may be detected. The zero crossings may be counted at each frequency position in the second dimension. An estimate of the input image's source resolution may be estimated from a comparison of the zero crossings. For video, this process may be performed across images of an input video sequences.

公开(公告)号：US20180332093A1

公开(公告)日：2018-11-15

申请号：US15590442

申请日：2017-05-09

Applicant: Apple Inc.

Inventor： David Makower ,  Paul A. Francis ,  Yu Chieh Lin

IPC: H04L29/06 ,  H04N19/146 ,  H04N19/172 ,  H04N19/119

CPC classification number: H04L65/607 ,  H04L65/4069 ,  H04L65/605 ,  H04N19/85

Abstract: Techniques are disclosed for estimating a source resolution of image data presented to a system. According to these techniques, input image data may be converted to a domain of frequency coefficients. Each coefficient may represent content of the input image along a respective pair of frequencies extending in two dimensions. For each set of frequency coefficients having a common frequency in one of the dimensions, zero crossings of coefficient values may be detected. The zero crossings may be counted at each frequency position in the second dimension. An estimate of the input image's source resolution may be estimated from a comparison of the zero crossings. For video, this process may be performed across images of an input video sequences.