STILL IMAGE PROVISION DEVICE

• US 20150085194A1
• Filed: 08/13/2014
• Published: 03/26/2015
• Est. Priority Date: 08/13/2013
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: KANNA, Yoshihiro
• Granted Patent: US 9,894,291 B2
• Time in Patent Office: Days
• US Class Current: 348/700
• CPC Class Codes: H04N 5/262 Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
• CPC Class Codes: H04N 5/91 Television signal processing therefor
• CPC Class Codes: H04N 9/87 Regeneration of colour television signals H04N9/80 takes precedence

Abstract

A moving image acquiring part acquires a moving image. A still image accumulating part stores still images. An image processing part calculates gains obtained by previously storing based on the costs of extraction of still images from a moving image, and extracts some still images with higher gains from among the still images composing the moving image and stores into the still image accumulating part. A request processing part retrieves a still image requested by a request source from the still image accumulating part and transmits to the request source and, when the still image requested by the request source is not stored in the still image accumulating part, extracts the still image requested by the request source from the moving image acquired by the moving image acquiring part and transmits to the request source.

Claims

1. A still image provision device transmitting a still image requested by a request source among a plurality of still images composing a moving image to the request source, the still image provision device comprising:

a moving image acquiring part configured to acquire a moving image;

a still image accumulating part configured to store still images composing the moving image;

an image processing part configured to, before request by the request source, calculate a gain of each of the still images obtained by storing the still image based on a cost of extraction of the still image from the moving image, and extract the still image with the higher gain from the moving image and store into the still image accumulating part; and

a request processing part configured to retrieve the still image requested by the request source from the still image accumulating part and transmit to the request source and, in a case where the still image requested by the request source is not stored in the still image accumulating part, extract the still image requested by the request source from the moving image acquired by the moving image acquiring part and transmit to the request source.

2. The still image provision device according to claim 1, wherein the image processing part is configured to calculate the gain of the still image based on a quality of the still image in addition to the cost.

3. The still image provision device according to claim 1, wherein the image processing part is configured to calculate the gain of the still image based on an amount of a difference between the still image and another of the still images in addition to the cost.

4. The still image provision device according to claim 1, wherein the image processing part is configured to extract the still image whose gain exceeds a given value from the moving image and store into the still image accumulating part.

5. The still image provision device according to claim 1, wherein:

the still image accumulating part is configured to store the gains of the still images that the still image accumulating part stores; and

the image processing part is configured to, in a case where a free space of the still image accumulating part is equal to or less than a given value, before storing a new one of the still images into the still image accumulating part, compare the gain of the new still image with a minimum one of the gains stored in the still image accumulating part and, only when the gain of the new still image is larger than the minimum gain, store the new still image and the gain of the new still image into the still image accumulating part and delete the still image with the smallest gain from the still image accumulating part.

6. A still image provision method executed by a still image provision device having a still image accumulating part configured to store still images and transmitting a still image requested by a request source among a plurality of still images composing a moving image to the request source, the still image provision method comprising:

before request by the request source, calculating a gain obtained by previously storing the still image based on a cost of extraction of the still image from the moving image, and extracting the still image with the higher gain from the moving image and storing into the still image accumulating part; and

retrieving the still image requested by the request source from the still image accumulating part and transmitting to the request source and, in a case where the still image requested by the request source is not stored in the still image accumulating part, extracting the still image requested by the request source from the moving image including the still image and transmitting to the request source.

7. The still image provision method according to claim 6, comprising:

in the calculating the gain, calculating the gain of the still image based on a quality of the still image in addition to the cost.

8. The still image provision method according to claim 6, comprising:

in the calculating the gain, calculating the gain of the still image based on an amount of a difference between the still image and another of the still images in addition to the cost.

9. The still image provision method according to claim 6, comprising:

in the storing, extracting the still image whose gain exceeds a given value from the moving image and storing into the still image accumulating part.

10. The still image provision method according to claim 6, wherein the still image accumulating part is configured to store the gains of the still images that the still image accumulating part stores, the still image provision method comprising:

in a case where a free space of the still image accumulating part is equal to or less than a given value, before storing a new one of the still images into the still image accumulating part, comparing the gain of the new still image with a minimum one of the gains stored in the still image accumulating part and, only when the gain of the new still image is larger than the minimum gain, storing the new still image and the gain of the new still image into the still image accumulating part and deleting the still image with the smallest gain from the still image accumulating part.

11. A non-transitory computer-readable medium storing a program comprising instructions for causing a computer, which has a still image accumulating part configured to store still images and transmits a still image requested by a request source among a plurality of still images composing a moving image to the request source, to function as:

a moving image acquiring part configured to acquire a moving image;

an image processing part configured to, before request by the request source, calculate a gain obtained by previously storing the still image based on a cost of extraction of the still image from the moving image, and extract the still image with the higher gain among the plurality of still images composing the moving image, from the moving image, and store into the still image accumulating part; and

a request processing part configured to retrieve the still image requested by the request source from the still image accumulating part and transmit to the request source and, in a case where the still image requested by the request source is not stored in the still image accumulating part, extract the still image requested by the request source from the moving image acquired by the moving image acquiring part and transmit to the request source.

12. The non-transitory computer-readable medium according to claim 11, wherein the image processing part is configured to calculate the gain of the still image based on a quality of the still image in addition to the cost.

13. The non-transitory computer-readable medium according to claim 11, wherein the image processing part is configured to calculate the gain of the still image based on an amount of a difference between the still image and another of the still images in addition to the cost.

14. The non-transitory computer-readable medium according to claim 11, wherein the image processing part is configured to extract the still image whose gain exceeds a given value from the moving image and store into the still image accumulating part.

15. The non-transitory computer-readable medium according to claim 11, wherein:

the still image accumulating part is configured to store the gains of the still images that the still image accumulating part stores; and

the image processing part is configured to, in a case where a free space of the still image accumulating part is equal to or less than a given value, before storing a new one of the still images into the still image accumulating part, compare the gain of the new still image with a minimum one of the gains stored in the still image accumulating part and, only when the gain of the new still image is larger than the minimum gain, store the new still image and the gain of the new still image into the still image accumulating part and delete the still image with the smallest gain from the still image accumulating part.