Scrolling motion detection within a video stream
AssigneeZoom Communications, Inc.
InventorsJing Wu, Zhaofeng Jia, Bo Ling, Qiyong Liu
Life of this patent
Estimating the term…
Abstract
Scrolling motion is detected within a video stream to output an indication of a scrolling motion vector for use in encoding a current picture of the video stream. A first line of pixels within a motion region of the current picture is identified. A second line of pixels matching the first line of pixels is identified within a last played picture of the video stream. The scrolling motion vector is determined based on a comparison of lines of pixels nearby the second line of pixels within the last played picture. The indication of the scrolling motion vector is then output for use in encoding the current picture.
Claims21
A method, comprising:
- determining that more than a predefined threshold of blocks in a current frame of a video stream are text-graphic blocks;
- classifying, in response to the determining, the current frame, prior to identifying a motion region of the current frame, as a text-graphic frame;
- identifying, in response to classifying the current frame as a text-graphic frame, a first line of pixels within the motion region of the current frame;
- identifying a second line of pixels matching the first line of pixels within a last played frame of the video stream;
- determining, in response to classifying the current frame as a text-graphic frame, a scrolling motion vector for the current frame based on a comparison of lines of pixels near the second line of pixels;
- and
- outputting an indication of the scrolling motion vector for encoding the current frame.
A non-transitory computer readable medium storing instructions that, when executed by a processor, cause a performance of operations comprising:
- determining that more than a predefined threshold of block in a current frame of a video stream are text-graphic blocks;
- classifying, in response to the determining, the current frame, prior to identifying a motion region of the current frame, as a text-graphic frame;
- identifying, in response to classifying the current frame as a text-graphic frame, a first line of pixels within the motion region of the current frame;
- identifying a second line of pixels matching the first line of pixels within a last played frame of the video stream;
- determining, in response to classifying the current frame as a text-graphic frame, a scrolling motion vector for the current frame based on a comparison of lines of pixels near the second line of pixels;
- and
- outputting an indication of the scrolling motion vector for use in encoding the current frame.
A system, comprising:
- a server device including a memory and a processor configured to execute instructions stored in the memory to:
- determine that more than a predefined threshold of blocks in a current frame of a video stream are text-graphic blocks;
- classify, in response to the determining, the current frame, prior to identifying a motion region of the current frame, as a text-graphic frame;
- identify, in response to classifying the current frame as a text-graphic frame, a first line of pixels within the motion region of the current frame;
- identify a second line of pixels matching the first line of pixels within a last played frame of the video stream;
- determine, in response to classifying the current frame as a text-graphic frame, a scrolling motion vector for the current frame based on a comparison of lines of pixels near the second line of pixels;
- and
- output an indication of the scrolling motion vector for use in encoding the current frame.
Dependencies are inferred from the claim text.