Method and its application for video recorder and player

Abstract

In a video recorder/player that increases a frame rate for only a channel in which an event occurs in images captured by a plurality of cameras and which performs event analysis with higher accuracy within limited processing resources and limited storage capacity, the channel in which the event occurs is set as an event CH and normal channels are set as normal CH. When any event occurs, a processing is divided in accordance with a situation at that time into a frame rate changing processing of the event CH, a frame rate changing processing of the normal CH and the event CH and a changing processing that changes the frame rate of the event CH within a possible range.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a video recorder and player according to an embodiment of the invention;

FIG. 2A is a detailed block diagram of input switching unit according to the embodiment of the invention;

FIG. 2B is a schematic view showing an example of a frame;

FIG. 3 is a detailed block view of an image processing unit according to the embodiment of the invention;

FIG. 4 is a detailed block view of an event detection unit according to the embodiment of the invention;

FIG. 5 is a flowchart useful for explaining an operation of frame rate changing unit according to the embodiment of the invention;

FIG. 6 is an explanatory view useful for explaining a frame rate changing processing according to the embodiment of the invention;

FIG. 7 is an explanatory view showing an example of GUI screen display according to the embodiment of the invention;

FIG. 8 is a block diagram when an image compression change is applied to the image processing unit according to the embodiment of the invention; and

FIG. 9 is a block diagram when network transfer is applied to the video recorder and player according to the invention.

Claims

1. A video recorder/player for acquiring image data from a plurality of cameras and storing the image data in recording media, including: a frame switcher for switching said plurality of cameras in a predetermined sequence and acquiring image data from each of said cameras at a predetermined frame rate;an image processor for detecting an event set in advance from said image data acquired from each of said cameras; andframe rate changing means for changing the frame rate of the image date from which the event is detected;said video recorder/player comprising:first means for changing only the frame rate of the image data from which the event is detected, when the event is detected;second means for changing both frame rate of the image data from which the event is detected and frame rate of other image data, when the event is detected; andthird means for changing the frame rate of other image data within a range in which a possible obstacle is as small as possible, when the event is detected, and for changing as much the frame rate of the image data from which the event is detected; wherein:said frame rate changing means selects a processing by said first means when the frame rate of the image data from which the event is detected is changeable, even when the frame rate of the image data other than the image data from which the event is detected is not changed;said frame rate changing means selects a processing by said second means when the image data for which no obstacle occurs even when the frame rate is lowered exists in the image data other than the image data from which the event is detected; andsaid frame rate changing means selects a processing by said third means when a counter-measure is not possible even when the frame rate of the image data other than the image data from which the event is detected is changed.

2. A video recorder/player according to claim 1, wherein said event is at least one of predetermined actions and articles such as motion of a subject, a face of a person, a doubtful action, a car and desertion.

3. A video recorder/player according to claim 1, which further comprises means for setting in advance a degree of importance of each event, and wherein said frame rate changing means preferentially executes the change of the frame rate of the image data in accordance with the degree of importance of the event of each image data when the event occurs in a plurality of image data.

4. A video recorder/player according to claim 3, wherein the degree of importance of the event is set by a user.

5. A video recorder/player according to claim 1, wherein said frame rate changing means changes an image compression ratio, too, at the time of acquisition of the image data when the frame rate of the image data is changed.

6. A video recorder/player according to claim 1, which further comprises network transmission control means, and wherein said frame rate changing means changes a transmission rate by said network transmission control means, when the frame rate of the image data is changed.