Image processor

• US 7,620,257 B2
• Filed: 03/21/2006
• Issued: 11/17/2009
• Est. Priority Date: 03/30/2005
• Status: Expired due to Fees

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Tanaka, Satoshi, Hashimoto, Seiji
• Primary Examiner(s): Alavi; Amir
• Application Number:
  US11/384,541
• Publication Number:
  US 20060236200A1
• Time in Patent Office: 1,337 Days
• Field of Search: 382/100, 382/173, 382218-219, 382/232, 382/233, 382/236, 382/239, 382/240, 382/248, 375/240.11, 375/240.17, 375/240.19, 375/240.24, 375/240.25, 714/758, 704/500, 341/143
• US Class Current: 382/240
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• CPC Class Codes: H04N 19/65 using error resilience
• CPC Class Codes: H04N 19/89 involving methods or arrangements for detection of transmission errors at the decoder

Abstract

An image processor includes a JPEG 2000 codec. The JPEG 2000 codec generates a plurality of levels of encoded data, and a checksum circuit integrates the encoded data for each of the levels to determine a checksum. The determined checksum is written together with the encoded data into a header of a stream. In decoding a desired level of the encoded data, a checksum is determined again on the basis of the encoded data and compared with the checksum written in the header. Accordingly, if the two matches with each other, it is concluded that the encoded data is not tampered. If the two does not match with each other, it is concluded that the encoded data is tampered and a warning message is displayed on a monitor.

Claims

1. An image processor comprising:

an encoder for encoding image data corresponding to each of a plurality of different frequency bands;

a recorder for recording in a recording medium the encoded image data generated by said encoder;

a first calculator for calculating a data amount of the encoded image data recorded by said recorder corresponding to each of said plurality of frequency bands;

a second calculator for calculating a data amount of desired encoded image data out of the encoded image data recorded in said recording medium corresponding to each of said plurality of frequency bands;

a comparator for comparing second numeric information indicative of the data amount of the data calculated by said second calculator with first numeric information indicative of the data amount calculated by said first calculator with respect to said desired encoded image data; and

an output for outputting a message in accordance with result of the comparison by said comparator.

2. An image processor depending on claim 1, further comprising:

a decoder for decoding said desired encoded image data; and

a display for displaying an image based on the image data decoded by said decoder, wherein said output outputs said message in relation to a displaying operation of said display.

3. An image processor according to claim 2, further comprising a selector for selecting one of said plurality of frequency bands, wherein said decoder decodes encoded image data components belonging to the frequency band selected by said selector, and said comparator performs a comparison focusing on the frequency band selected by said selector.

4. An image processor according to claim 3, further comprising:

an assigner for assigning said first numeric information to the encoded image data recorded by said recorder; and

a detector for detecting the first numeric information assigned to said desired encoded image data prior to the comparison by said comparator.

5. An image processor according to claim 4, wherein an encoding format of said encoder conforms to a wavelet transformation format.

6. An image processor according to claim 4, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

7. An image processor according to claim 3, wherein an encoding format of said encoder conforms to a wavelet transformation format.

8. An image processor according to claim 3, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

9. An image processor according to claim 2, further comprising:

an assigner for assigning said first numeric information to the encoded image data recorded by said recorder; and

a detector for detecting the first numeric information assigned to said desired encoded image data prior to the comparison by said comparator.

10. An image processor according to claim 9, wherein an encoding format of said encoder conforms to a wavelet transformation format.

11. An image processor according to claim 9, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

12. An image processor according to claim 2, wherein an encoding format of said encoder conforms to a wavelet transformation format.

13. An image processor according to claim 2, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

14. An image processor according to claim 1, further comprising:

an assigner for assigning said first numeric information to the encoded image data recorded by said recorder; and

a detector for detecting the first numeric information assigned to said desired encoded image data prior to the comparison by said comparator.

15. An image processor according to claim 14, wherein an encoding format of said encoder conforms to a wavelet transformation format.

16. An image processor according to claim 14, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

17. An image processor according to claim 1, wherein an encoding format of said encoder conforms to a wavelet transformation format.

18. An image processor according to claim 17, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

19. An image processor according to claim 1, further comprising a photographer for photographing an object scene, wherein said image data to be encoded by the encoder depicts an image of the object scene photographed by the photographer.

20. An image processing method comprising following steps of:

an encoding step of encoding image data corresponding to each of a plurality of different frequency bands;

a recording step of recording in a recording medium the encoded image data generated in said encoding step;

a first calculation step of calculating a data amount of the encoded image data recorded in said recording step corresponding to each of said plurality of frequency bands;

a second calculation step of calculating a data amount of desired encoded image data out of the encoded image data recorded in said recoding medium corresponding to each of said plurality of frequency bands;

a comparison step of comparing second numeric information indicative of the data amount of the desired encoded image data calculated in said second calculation step with first numeric information indicative of the data amount calculated in said first calculation step with respect to said desired encoded image data; and

an output step of outputting a message according to result of the comparison by said comparator.