公开(公告)号：US09628805B2

公开(公告)日：2017-04-18

申请号：US14716685

申请日：2015-05-19

Applicant: Avast Software s.r.o.

Inventor： Martin Smarda ,  Pavel Sramek

IPC: G06K9/00 ,  H04N19/126 ,  G06F3/0481 ,  H04N19/625 ,  G06F21/56 ,  H04N1/32 ,  G06F17/30

CPC classification number: H04N19/126 ,  G06F3/0481 ,  G06F3/04817 ,  G06F17/30247 ,  G06F21/564 ,  G06F21/565 ,  H04N1/32283 ,  H04N19/625

Abstract: Systems and methods generate a perceptual image hash of an image. The perceptual image hash can be generated from multiple features extracted from a DCT transformation of the image. The perceptual image hash can be compared to other perceptual image hash values using a weighted Hamming distance function.

公开(公告)号：US10594728B2

公开(公告)日：2020-03-17

申请号：US15638160

申请日：2017-06-29

Applicant: Avast Software s.r.o.

Inventor： Dmitriy Kuznetsov ,  Martin Smarda ,  Pavel Sramek

IPC: G06F21/57 ,  H04L29/06 ,  G06F21/55 ,  H04L29/12

Abstract: Detecting a Domain Name Service (DNS) hijacking includes resolving names in a hijack target group list to their respective Internet Protocol (IP) addresses. In response to determining that two names in the hijack target group list resolved to a common IP address, a determination is made whether a legitimate reason exists for the two names in the hijack target group list to resolve to the common IP address. In response to determining that a legitimate reason does not exist for the two names in the hijack target group list to resolve to a common IP address, a DNS hijacking is indicated.

公开(公告)号：US20150339829A1

公开(公告)日：2015-11-26

申请号：US14716685

申请日：2015-05-19

Applicant: Avast Software s.r.o.

Inventor： Martin Smarda ,  Pavel Sramek

IPC: G06T7/00 ,  H04N19/625 ,  H04N19/126 ,  G06F3/0481

CPC classification number: H04N19/126 ,  G06F3/0481 ,  G06F3/04817 ,  G06F17/30247 ,  G06F21/564 ,  G06F21/565 ,  H04N1/32283 ,  H04N19/625

Abstract: Systems and methods generate a perceptual image hash of an image. The perceptual image hash can be generated from multiple features extracted from a DCT transformation of the image. The perceptual image hash can be compared to other perceptual image hash values using a weighted Hamming distance function.

Abstract translation: 系统和方法产生图像的感知图像散列。 感知图像散列可以从从图像的DCT变换中提取的多个特征生成。 可以使用加权Hamming距离函数将感知图像散列与其他感知图像散列值进行比较。

公开(公告)号：US20190303387A1

公开(公告)日：2019-10-03

申请号：US16370952

申请日：2019-03-30

Applicant: Avast Software s.r.o.

Inventor： Martin Smarda ,  Pavel Srámek

IPC: G06F16/27 ,  G06F9/54 ,  G06K9/62

Abstract: Systems and methods capable of initializing centroids in large datasets before commencement of clustering operations. The systems and methods can utilize a random sampling window to increase the speed of centroid initialization. The systems and methods can be modified to leverage parallelism and be configured for execution on multi-node compute clusters. Optionally, the initialization systems and methods can include post-initialization centroid discarding and/or re-assignment operations that adaptively control cluster sizes.

公开(公告)号：US20180007088A1

公开(公告)日：2018-01-04

申请号：US15638160

申请日：2017-06-29

Applicant: Avast Software s.r.o.

Inventor： Dmitriy Kuznetsov ,  Martin Smarda ,  Pavel Sramek

IPC: H04L29/06 ,  G06F21/55 ,  H04L29/12 ,  G06F21/57

Abstract: Detecting a Domain Name Service (DNS) hijacking includes resolving names in a hijack target group list to their respective Internet Protocol (IP) addresses. In response to determining that two names in the hijack target group list resolved to a common IP address, a determination is made whether a legitimate reason exists for the two names in the hijack target group list to resolve to the common IP address. In response to determining that a legitimate reason does not exist for the two names in the hijack target group list to resolve to a common IP address, a DNS hijacking is indicated.