Method of pre-processing digital images, and digital image preprocessing system

Patent metadata

Field	Value
Publication number	US-10110929-B2
Application number	US-201615246951-A
Country	US
Kind code	B2
Filing date	Aug 25, 2016
Priority date	Aug 27, 2015
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A method of pre-processing digital images captured by an image sensor for encoding is disclosed. The method comprises receiving a first digital image, receiving information representative of a movement of the image sensor at a time of capture of said first digital image), and pre-processing said first digital image. At least one parameter of said pre-processing is dependent on said information representative of movement. A digital image pre-processing system is also disclosed.

First claim

What is claimed is:

1. A method of pre-processing digital images captured by an image sensor for encoding, comprising:
receiving a first digital image,
receiving information representative of a movement of the image sensor at a time of capture of said first digital image,
modifying at least one parameter of pre-processing of the digital image based on said information representative of movement,
pre-processing said first digital image according to the at least one modified parameter to generate a pre-processed image,
wherein the modifying causes a bitrate of the pre-processed image when encoded to be lower than a bitrate of a pre-processed image that would be generated by applying the pre-processing without the modified parameter and when encoded.

2. The method according to claim 1 , wherein if said movement of the image sensor is above a predetermined threshold, said at least one parameter of said pre-processing is modified such that the first digital image is less processed by said pre-processing than if said movement were equal to or below said threshold.

3. The method according to claim 2 , wherein said at least one parameter of said pre-processing is modified such that at least one pre-processing procedure is disabled.

4. The method according to claim 2 , wherein said at least one parameter is modified such that at least one pre-processing procedure processes said first digital image, but to a greater or lesser extent.

5. The method according to claim 1 , wherein said at least one parameter of said pre-processing is modified such that at least one pre-processing procedure that is otherwise disabled is enabled.

6. The method according to claim 1 , wherein said pre-processing comprises performing at least one pre-processing procedure chosen from the group consisting of sharpening, adding contrast, tone mapping, colour correction, noise filtering, blurring, Bayer pattern sampling, demosaicing, HDR merging, controlling focus, controlling exposure, and controlling gain.

7. The method according to claim 1 , wherein said information representative of a movement of the image sensor is provided by a pan, tilt and/or zoom controller controlling movement of said image sensor.

8. The method according to claim 1 , wherein said information representative of a movement of the image sensor is provided by a motion sensor.

9. The method according to claim 1 , wherein said at least one parameter is modified over a plurality of frames in preparation for a planned movement of the image sensor.

10. The method according to claim 1 , further comprising encoding said first digital image as an intra-frame in preparation for a planned movement of the image sensor.

11. A computer program product comprising a computer-readable storage medium with instructions adapted to carry out the method according to claim 1 when executed by a processor.

12. A digital image pre-processing system for pre-processing input images captured by an image sensor for encoding, the system comprising:
an image receiving module arranged to receive input images;
a movement information receiving module arranged to receive information representative of a movement of the image sensor at a time of capture of said input images; and
a pre-processing module arranged to modify at least one parameter of pre-processing of the input images based on said information representative of movement, and to pre-process the input images before encoding to generate pre-processed images,
wherein the modifying causes bitrates of the pre-processed images when encoded to be lower than bitrates of pre-processed images that would be generated by applying the pre-processing without the modified parameter and when encoded.

13. The digital image pre-processing system according to claim 12 , wherein said pre-processing module is arranged to perform at least one pre-processing procedure chosen from the group consisting of sharpening, adding contrast, tone mapping, colour correction, noise filtering, blurring, Bayer pattern sampling, demosaicing, HDR merging, controlling focus, controlling exposure, and controlling gain.

14. The digital image pre-processing system according to claim 12 , wherein said movement information receiving module is communicatively connected to a pan, tilt and/or zoom controller controlling movement of said image sensor and/or to a motion sensor.

15. A camera comprising a pre-processing system according to claim 12 .

Assignees

• Axis Ab

Inventors

• Martins Alexandre
• Edpalm Viktor
• Danielsson Fang Xing
• Persson Lars
• Pihl Fredrik

Classifications

• H04N23/80

  Camera processing pipelines; Components thereof · CPC title

• H04N23/682 Primary

  Vibration or motion blur correction · CPC title

• H04N23/6811

  based on the image signal · CPC title

• H04N23/57

  Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices · CPC title

• H04N19/117

  Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) · CPC title