Image pickup device and image pickup method

• US 20060132618A1
• Filed: 09/30/2003
• Published: 06/22/2006
• Est. Priority Date: 09/30/2003
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Matoba, Narihiro, Fujita, Takeo
• Granted Patent: US 7,440,010 B2
• Time in Patent Office: Days
• US Class Current: 348/222.100
• CPC Class Codes: H04N 1/00 Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
• CPC Class Codes: H04N 1/2112 using still video cameras
• CPC Class Codes: H04N 1/212 Motion video recording combined with still video recording television signal recording H04N5/76
• CPC Class Codes: H04N 1/2137 with temporary storage before final recording, e.g. in a frame buffer
• CPC Class Codes: H04N 1/2158 using a detachable storage unit
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/149 by estimating the code amount by means of a model, e.g. mathematical model or statistical model
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/907 using static stores, e.g. storage tubes or semiconductor memories H04N5/91 takes precedence
• CPC Class Codes: H04N 9/804 involving pulse code modulation of the colour picture signal components

Abstract

An image pickup apparatus includes a characteristic value calculation circuit 16 for extracting a characteristic value used for predicting an amount of codes to be generated at a time of compressing a video signal acquired by a solid state image pickup device from the video signal, and a compression coefficient control circuit 17 for controlling a compression coefficient which is used by an image compression unit 18 based on the characteristic value acquired by the characteristic value calculation circuit 16. The compression coefficient control circuit uses the characteristic value acquired by the characteristic value calculation circuit 16 at a time of allowing users to check an image to be picked-up before picking up an image, and determines the compression coefficient at a time of picking up an image.

Claims

1. An image pickup apparatus provided with a solid state image pickup device and a data compression means for compressing a video signal acquired by said solid state image pickup device, characterized in that said image pickup apparatus comprises:

a characteristic value calculation means for extracting a characteristic value used for predicting an amount of codes to be generated at a time of compressing a video signal acquired by said solid state image pickup device from the video signal; and

a compression coefficient control means for controlling a compression coefficient which is used by said data compression means based on the characteristic value acquired by said characteristic value calculation means, said compression coefficient control means using the characteristic value acquired by said characteristic value calculation means at a time of allowing users to check an image to be picked-up before picking up the image, and determining the compression coefficient at a time of picking up an image.

2. The image pickup apparatus according to claim 1, characterized in that said characteristic value calculation means divides the picked-up image into two or more areas, calculates a characteristic value for each of the two or more areas in addition to the characteristic value acquired from the whole of the picked-up image, and outputs the largest one of the characteristic values acquired for the two or more areas, as a local maximum characteristic value, and said compression coefficient control means controls the compression coefficient which is used by said data compression means based on the two characteristic values acquired by said characteristic value calculation means.

3. The image pickup apparatus according to claim 1, characterized in that said characteristic value calculation means stores characteristic values acquired for two or more frames, and makes a correction to a characteristic value which said characteristic value calculation means will output according to a change in the characteristic values acquired for the two or more frames.

4. The image pickup apparatus according to claim 1, characterized in that said compression coefficient control means rewrites information about on a list of data or coefficients using data transmitted thereto by using communications with external equipment.

5. An image pickup method of picking up an image using a solid state image pickup device, and performing image compression processing on the picked-up image, and recording the compressed image in a recording medium, characterized in that said method comprising:

a characteristic value calculation step for extracting a characteristic value used for predicting an amount of codes to be generated at a time of compressing a video signal acquired by said solid state image pickup device from the video signal;

a compression coefficient control step for controlling a compression coefficient which is used for data compression based on the characteristic value acquired in said characteristic value calculation step; and

a data compression step for compressing the video signal acquired by said solid state image pickup device using the compression coefficient acquired in said compression coefficient control step, said compression coefficient control step including steps of using the characteristic value acquired by said characteristic value calculation means at a time of allowing users to check an image to be picked-up before picking up the image, and determining the compression coefficient at a time of picking up an image.