Multimedia data recording apparatus, monitor system, and multimedia data recording method

• US 7,609,941 B2
• Filed: 10/20/2004
• Issued: 10/27/2009
• Est. Priority Date: 10/20/2003
• Status: Expired due to Fees

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Matsukawa, Takayuki, Yoshio, Hiroaki, Kawai, Fumi
• Primary Examiner(s): Tran; Thai
• Assistant Examiner(s): TOPGYAL, GELEK W
• Application Number:
  US10/541,025
• Publication Number:
  US 20060152636A1
• Time in Patent Office: 1,833 Days
• Field of Search: 386/46, 386/94, 386/95, 348/143, 348/150, 348/156, 360/5
• US Class Current: 386/248
• CPC Class Codes: G08B 13/19667 Details realated to data compression, encryption or encoding, e.g. resolution modes for reducing data volume to lower transmission bandwidth or memory requirements
• CPC Class Codes: G08B 13/19669 Event triggers storage or change of storage policy
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

A multimedia data recording apparatus is disclosed that enables large-volume recorded data to be recorded for a long period in accordance with the importance of the data, by means of a simple configuration and simple processing, and without imposing a heavy load on the system. In this apparatus, a layer classification section classifies video data captured by a surveillance camera and input via a video processing section into a plurality of layers on a frame-by-frame basis according to importance. A data recording section assigns a file to each layer and records classified data in a data recording medium. If an information amount reduction section detects that the vacant capacity of the data recording medium has reached or fallen below a threshold value, it deletes a frame belonging to the lowest layer among the plurality of layers.

Claims

1. A monitoring system comprising:

a multimedia data recording apparatus comprising;

a layer classifier that classifies multimedia data into a plurality of hierarchical layers according to data contents or data precision;

a recorder that continuously records data classified into said layers in a memory; and

a data amount reducer that, when vacant capacity of said memory is at or below a threshold value, performs deletion in an order starting with data classified into a lower layer of said hierarchical layers among data recorded in said memory;

said monitoring system further comprising;

a measurer that measures frequency of access to data recorded in said memory; and

a changer that changes at least one or a plurality of layers in which data whose frequency of access is greater than or equal to a predetermined value among data recorded in said memory to a protected layer that is not subject to data amount reduction by said data amount reducer.

2. The monitoring system according to claim 1, wherein said layer classification section classified said multimedia data into a plurality of hierarchical layers according to frame rate, required image quality or resolution, image variation amount between frames, required storage time, MPEG (Moving Picture Experts Group) data picture type, importance of a recorded event, or an enhancement layer of data coded by an MPEG scalable coding method.

3. The monitoring system according to claim 1, wherein said data amount reducer performs deletion in an order starting with older data among data or less important data recorded in a lower layer.

4. The monitoring system according to claim 3, wherein said data amount reducer does not delete data that has not passed a minimum storage time among data recorded in a lower layer.

5. The monitoring system according to claim 1, wherein:

said layer classifier sets said multimedia data in a plurality of segments according to a time of acquisition of the data and then classifies said multimedia data into said layers for each said segment; and

said data amount reducer selects a segment whose said time of acquisition is older, and performs deletion in an order starting with data recorded in a lower layer within the segment.