DATA PROCESSING APPARATUS AND CONTROL METHOD THEREOF

• US 20120020567A1
• Filed: 07/14/2011
• Published: 01/26/2012
• Est. Priority Date: 07/21/2010
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Natori, Ryoko, Shiraga, Shinji
• Granted Patent: US 8,891,877 B2
• Time in Patent Office: Days
• US Class Current: 382/195
• CPC Class Codes: G06V 20/53 Recognition of crowd images, e.g. recognition of crowd congestion

Abstract

A data processing apparatus that executes determining processing, using a plurality of stages, for determining whether or not a partial image sequentially extracted from an image of each frame of a moving image corresponds to a specific pattern, assigns a plurality of discriminators to each stage such that a plurality of partial images are processed in parallel. The data processing apparatus divides an image into a plurality of regions, and, for the image of each region, calculates a passage rate or accumulated passage rate from a ratio between the number of partial images input to a stage and the number of partial images determined to correspond to the specific pattern. The assignment of the discriminators to each stage is changed based on the passage rate or accumulated passage rate of the image processed immediately of a region to which the partial image extracted from the image being processed belongs.

Claims

1. A data processing apparatus that executes determining processing for determining whether or not a partial image sequentially extracted from an image of each frame of a moving image corresponds to a specific pattern, the determining processing having a plurality of stages, the data processing apparatus comprising:

a plurality of discriminators that are assigned to any of the plurality of stages, and that determine whether or not the partial image corresponds to the specific pattern by identification processing according to the assigned stage and output the partial image to a subsequent stage to cause the partial image to be processed in the subsequent stage when it has been determined that the partial image corresponds to the specific pattern;

an assignment unit that assigns the plurality of discriminators to each stage such that a plurality of partial images are processed in parallel;

a calculation unit that divides the image into a plurality of regions, and, for an image of each region, calculates a passage rate or accumulated passage rate from a ratio of the number of partial images input to a stage to the number of partial images determined to correspond to the specific pattern, and holds the calculated passage rate or accumulated passage rate on a stage basis in a holding unit; and

a changing unit that acquires, from the holding unit, the passage rate or accumulated passage rate of an image, processed immediately previously, of a region to which the partial image extracted from the image being processed belongs, and changes assignment of the discriminators to each stage by the assignment unit based on the acquired passage rate or accumulated passage rate.

2. The apparatus according to claim 1,

wherein the changing unit, based on the passage rate or accumulated passage rate held in the holding unit, calculates a data amount to be processed in each stage, decides the number of discriminators to be assigned to each stage based on a ratio of the data amounts between stages, and changes the assignment of the discriminators to each stage according to the decided number of discriminators.

3. The apparatus according to claim 1, further comprising a storing unit that, with respect to each of the plurality of stages, stores a processing time required by each discriminator to process the partial image,

wherein the changing unit calculates a data amount to be processed in each stage based on the passage rate or accumulated passage rate, and decides, with respect to each stage, the number of discriminators to be assigned to each stage such that a maximum value of an average processing time of each stage obtained from the data amount, the processing time and the number of discriminators distributed to the stage is minimized.

4. The apparatus according to claim 1,

wherein the changing unit monitors whether or not processing by each discriminator has finished, and when the numbers of assigned discriminators are different between adjacent stages, connects a discriminator of a preceding one of the adjacent stages to a discriminator of a subsequent one of the adjacent stages on which processing has finished in the order in which the processing of the discriminator in the preceding stage finishes.

5. The apparatus according to claim 1, further comprising a detecting unit that detects a motion vector of each pixel based on movement of an object between frames,

wherein the changing unit moves a position of each pixel back by an amount of movement indicated by a corresponding motion vector, acquires, from the holding unit, the passage rate or accumulated passage rate of a region to which the moved position belongs, and changes the assignment of the discriminators to each stage in the assignment unit based on the acquired passage rate or accumulated passage rate.

6. A control method of a data processing apparatus that executes determining processing for determining whether or not a partial image sequentially extracted from an image of each frame of a moving image corresponds to a specific pattern, the determining processing having a plurality of stages, and the data processing apparatus including a plurality of discriminators that are assigned to any of the plurality of stages, and that determine whether or not the partial image corresponds to the specific pattern by identification processing according to the assigned stage and output the partial image to a subsequent stage to cause the partial image to be processed in the subsequent stage when it has been determined that the partial image corresponds to the specific pattern, the control method comprising the steps of:

assigning the plurality of discriminators to each stage such that a plurality of partial images are processed in parallel;

dividing the image into a plurality of regions, and, for an image of each region, calculating a passage rate or accumulated passage rate from a ratio of the number of partial images input to a stage to the number of partial images determined to correspond to the specific pattern, and holding the calculated passage rate or accumulated passage rate on a stage basis in a holding unit; and

acquiring, from the holding unit, the passage rate or accumulated passage rate of an image, processed immediately previously, of a region to which the partial image extracted from the image being processed belongs, and changing assignment of the discriminators to each stage in the assigning step based on the acquired passage rate or accumulated passage rate.