Image data transfer method, image processing device, and imaging system

• US 20070279426A1
• Filed: 04/17/2007
• Published: 12/06/2007
• Est. Priority Date: 04/17/2006
• Status: Active Grant

• Current Assignee: Godo Kaisha IP Bridge 1 (IP Bridge, Inc.)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kitamura, Shinji, Shimazu, Yoshihisa, Tanaka, Yasuharu, Nagata, Taichi
• Granted Patent: US 7,978,198 B2
• Time in Patent Office: Days
• US Class Current: 345/544
• CPC Class Codes: G06F 12/0207 with multidimensional access, e.g. row/column, matrix
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

An image data transfer method including the steps of: (a) reading pixel data of a two-dimensional image stored in a first image storage and having a plurality of pixels, the position of each of the pixels being represented by coordinates of first and second directions, the pixel data being read by scanning data transfer units of the pixel data in the second direction where each of the data transfer units is formed by data of a predetermined number of pixels consecutive in the first direction; (b) writing the data transfer units read at step (a) in a temporary data storage where data is stored at a position designated by a combination of first and second addresses, the data transfer units being written in burst mode in a region of the temporary data storage in which the first addresses are consecutive while the second address is fixed; and (c) reading the data transfer units written in the temporary data storage from the region in which the first addresses are consecutive while the second address is fixed in burst mode and writing the read data transfer units in a second image storage.

Claims

1. An image data transfer method, comprising the steps of:

(a) reading pixel data of a two-dimensional image stored in a first image storage and having a plurality of pixels, the position of each of the pixels being represented by coordinates of first and second directions, the pixel data being read by scanning data transfer units of the pixel data in the second direction where each of the data transfer units is formed by data of a predetermined number of pixels consecutive in the first direction;

(b) writing the data transfer units read at step (a) in a temporary data storage where data is stored at a position designated by a combination of first and second addresses, the data transfer units being written in burst mode in a region of the temporary data storage in which the first addresses are consecutive while the second address is fixed; and

(c) reading the data transfer units written in the temporary data storage from the region in which the first addresses are consecutive while the second address is fixed in burst mode and writing the read data transfer units in a second image storage.

2. The image data transfer method of claim 1, wherein:

step (a) includes separately scanning data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image in the second direction, where the lines are ordered in the second direction; and

step (b) includes writing the data transfer units of the odd-numbered lines and the data transfer units of the even-numbered lines in different regions.

3. The image data transfer method of claim 2, wherein step (b) includes writing the data transfer units of the odd-numbered lines and the data transfer units of the even-numbered lines while the second address is fixed.

4. The image data transfer method of claim 2, further comprising a field/frame conversion step of reading the data transfer units written in the temporary data storage and writing the read data transfer units in the temporary data storage in a frame mapping format.

5. The image data transfer method of claim 1, further comprising a frame/field conversion step of reading the data transfer units written in the temporary data storage and writing the read data transfer units in the temporary data storage in a field mapping format.

6. The image data transfer method of claim 5, wherein the frame/field conversion step includes writing data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the read two-dimensional image while the second address is fixed, where the lines are ordered in the second direction.

7. The image data transfer method of claim 1, wherein:

step (a) includes reading a blue color difference signal and a red color difference signal as the pixel data in the form of data transfer units; and

step (b) includes alternately writing the data transfer units of the blue color difference signal and the data transfer units of the red color difference signal.

8. The image data transfer method of claim 1, wherein:

step (a) includes reading a luminance signal, a blue color difference signal, and a red color difference signal as the pixel data in the form of data transfer units; and

step (b) includes alternately writing the data transfer units of the luminance signal, the data transfer units of the blue color difference signal, and the data transfer units of the red color difference signal.

9. The image data transfer method of claim 1, further comprising the steps of:

(a1) separately reading data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image stored in the first image storage by scanning in the second direction, where the lines are ordered in the second direction;

(b1) writing the read data transfer units of the odd-numbered lines in another temporary data storage where data is stored at a position designated by a combination of third and fourth addresses, the data transfer units of the odd-numbered lines being written in burst mode in a region of the another temporary data storage in which the third addresses are consecutive while the fourth address is fixed;

(b2) writing the read data transfer units of the even-numbered lines in burst mode in another region of the another temporary data storage which is different from the region written at step (b1) and in which the third addresses are consecutive while the fourth address is fixed; and

(c1) reading the data transfer units written in the another temporary data storage from the regions in which the third addresses are consecutive while the fourth address is fixed in burst mode and writing the read data transfer units in the second image storage, wherein any one of step (c) and step (c1) is performed.

10. The image data transfer method of claim 9, wherein step (b1) and step (b2) include writing the read data transfer units of the odd-numbered lines and the read data transfer units of the even-numbered lines while the fourth address is fixed.

11. The image data transfer method of claim 9, wherein:

if step (c) is performed, supply of a clock to the another temporary data storage is stopped; and

if step (c1) is performed, supply of a clock to the temporary data storage is stopped.

12. The image data transfer method of claim 1, further comprising the steps of:

(a1) separately reading data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image stored in the first image storage by scanning in the second direction, where the lines are ordered in the second direction;

(b1) writing the read data transfer units of the odd-numbered lines in burst mode in a region of the temporary data storage which is different from the region written at step (b) and in which the first addresses are consecutive while the second address is fixed; and

(b2) writing the read data transfer units of the even-numbered lines in burst mode in a region of the temporary data storage which is different from the regions written at steps (b) and (b1) and in which the first addresses are consecutive while the second address is fixed.

13. The image data transfer method of claim 12, wherein any one of step (b) and a combination of steps (b1) and (b2) is selected according to a mapping type signal and performed.

14. The image data transfer method of claim 13, wherein the mapping type signal is switched on a frame by frame basis.

15. The image data transfer method of claim 13, wherein the mapping type signal is switched such that step (b) is performed when a moving picture which is to be reproduced is a progressive image, and steps (b1) and (b2) are performed when a moving picture which is to be reproduced is an interlaced image.

16. The image data transfer method of claim 12, wherein any one of step (b), a combination of steps (b1) and (b2), and a combination of steps (b), (b1) and (b2) is adaptively selected and performed.

17. The image data transfer method of claim 16, wherein the selection is performed according to a frame size of an image which is to be processed.

18. The image data transfer method of claim 16, wherein the selection is performed according to a load on the temporary data storage.

19. The image data transfer method of claim 16, wherein the selection is performed according to image size information included in header information.

20. The image data transfer method of claim 16, wherein:

image processing requests from a plurality of clients are processed in a time-division manner; and

the selection is performed for each of the plurality of clients.

21. The image data transfer method of claim 20 wherein, in response to an image processing request from a new client, a capacity of a unused region of the temporary data storage is calculated, and the selection is performed according to the capacity of the unused region.

22. The image data transfer method of claim 21 wherein, if a region necessary for processing cannot be secured, the new client is notified of the unavailability.

23. The image data transfer method of claim 22 wherein, if a region necessary for performing steps (b), (b1) and (b2), the new client is notified of the unavailability.

24. The image data transfer method of claim 22, further comprising the steps of:

when the new client is notified of the unavailability, asking one of the plurality of clients for which steps (b), (b1) and (b2) are performed to release part of a region allocated to the client;

when the part of the region is released, performing a process for the new client using the released part of the region.

25. The image data transfer method of claim 20 wherein, in response to an image processing request received from a new client, the selection is performed anew on the plurality of clients and the new client.

26. The image data transfer method of claim 1, wherein:

if the two-dimensional image has a smaller number of data transfer units in the first direction than in the second direction, step (a) includes reading the data transfer units by scanning in the second direction; and

if otherwise, step (a) includes reading the data transfer units by scanning in the first direction.

27. The image data transfer method of claim 1, wherein:

the first image storage stores a reconstructed image generated in encoding or decoding of a moving picture; and

a reference image used in encoding or decoding of a moving picture is read from the second image storage.

28. The image data transfer method of claim 27, wherein step (b) includes writing in a region capable of storing a reconstructed image of one frame plus an expanded region.

29. The image data transfer method of claim 28, wherein the expanded region has a capacity capable of storing, among rows of a macroblock of the two-dimensional image, a row including a target macroblock and macroblocks upper than the target macroblock which are used for motion search or motion compensation.

30. The image data transfer method of claim 27, further comprising the steps of:

(a1) separately reading data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image stored in the first image storage by scanning in the second direction, where the lines are ordered in the second direction;

(b1) writing the read data transfer units of the odd-numbered lines in burst mode in a region of the temporary data storage which is different from the region written at step (b) and in which the first addresses are consecutive while the second address is fixed; and

(b2) writing the read data transfer units of the even-numbered lines in burst mode in another region of the temporary data storage which is different from the regions written at step (b) and step (b1) and in which the first addresses are consecutive while the second address is fixed;

wherein step (b) is performed on the luminance signal, and any one of step (b), a combination of steps (b1) and (b2), and a combination of steps (b), (b1) and (b2) is selected for and performed on the blue color difference signal and the red color difference signal.

31. The image data transfer method of claim 30, wherein each of step (b1) and step (b2) performs writing in a region capable of storing a reconstructed image of one field plus an expanded region.

32. The image data transfer method of claim 31, wherein the expanded region has a half of a capacity capable of storing, among rows of a macroblock of the two-dimensional image, a row including a target macroblock and macroblocks upper than the target macroblock which are used for motion search or motion compensation.

33. The image data transfer method of claim 1, wherein:

step (b) includes

(d) establishing a handshake between a device including the first and second image storages and a memory arbitrator for transferring the data transfer units read at step (a), and

(e) transferring the data transfer units read at step (a) to the temporary data storage via the memory arbitrator; and

step (c) includes

(f) establishing a handshake between the device and the memory arbitrator for transferring the data transfer units read from the temporary data storage, and

(g) transferring the data transfer units read from the temporary data storage to the second image storage via the memory arbitrator.

34. The image data transfer method of claim 33, wherein step (e) includes transferring the data transfer units read at step (a) in the form of new data transfer units from the memory arbitrator to the temporary data storage, where each of the new data transfer units is formed by a predetermined number of data transfer units, and

if a number of data transfer units smaller than the predetermined number remain untransferred, after a data transfer unit adjacent in the second direction to the remaining data transfer unit is read, a new data transfer unit formed by the remaining data transfer unit and the adjacent data transfer unit is transferred to the temporary data storage.

35. An image data transfer method used in image processing which requires a temporary memory region, characterized in that the image processing is performed on an image which is a process unit having a DX by DY data transfer units, where DX is a natural number representing the number of data transfer units in a line extending in the first direction and DY is a natural number representing the number of data transfer units in a line extending in the second direction, in such a manner that:

if DX≧

DY, the image is scanned in the first direction to write the data transfer units in burst mode on a DX by DX basis in consecutive addresses of the temporary memory region; and

if DX<

DY, the image is scanned in the second direction to write the data transfer units in burst mode on a DY by DY basis in consecutive addresses of the temporary memory region.

36. An image processing device, comprising:

a first read section for reading pixel data of a two-dimensional image stored in a first image storage and having a plurality of pixels, the position of each of the pixels being represented by coordinates of first and second directions, the pixel data being read by scanning data transfer units of the pixel data in the second direction where each of the data transfer units is formed by data of a predetermined number of pixels consecutive in the first direction, and writing the read data transfer units in a temporary data storage where data is stored at a position designated by a combination of first and second addresses, the data transfer units being written in burst mode in a region of the temporary data storage in which the first addresses are consecutive while the second address is fixed; and

a first write section for reading the data transfer units written in the temporary data storage from the region in which the first addresses are consecutive while the second address is fixed in burst mode and writing the read data transfer units in a second image storage.

37. The image processing device of claim 36, wherein:

the first read section reads the pixel data by separately scanning data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image in the second direction, where the lines are ordered in the second direction; and

the first read section writes the data transfer units of the odd-numbered lines and the data transfer units of the even-numbered lines in different regions.

38. The image processing device of claim 37, further comprising a field/frame converter for reading the data transfer units written in the temporary data storage and writing the read data transfer units in the temporary data storage in a frame mapping format.

39. The image processing device of claim 36, further comprising:

a second read section for separately reading data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image stored in the first image storage by scanning in the second direction, where the lines are ordered in the second direction, writing the read data transfer units of the odd-numbered lines in another temporary data storage where data is stored at a position designated by a combination of third and fourth addresses, the data transfer units of the odd-numbered lines being written in burst mode in a region of the another temporary data storage in which the third addresses are consecutive while the fourth address is fixed, and writing the read data transfer units of the even-numbered lines in burst mode in another region of the another temporary data storage which is different from the region storing the data transfer units of the odd-numbered lines and in which the third addresses are consecutive while the fourth address is fixed; and

a second write section for reading the data transfer units written in the another temporary data storage from the regions in which the third addresses are consecutive while the fourth address is fixed in burst mode and writing the read data transfer units in the second image storage.

40. The image processing device of claim 36, further comprising a second read section for separately reading data transfer units of odd-numbered lines and data transfer units of even-numbered lines of the two-dimensional image stored in the first image storage by scanning in the second direction, where the lines are ordered in the second direction, writing the read data transfer units of the odd-numbered lines in burst mode in a region of the temporary data storage which is different from the region written by the first read section and in which the first addresses are consecutive while the second address is fixed, and writing the read data transfer units of the even-numbered lines in burst mode in a region of the temporary data storage which is different from the region written by the first read section and different from the region storing the read data transfer units of the odd-numbered lines and in which the first addresses are consecutive while the second address is fixed.

41. The image processing device of claim 40, further comprising a selector for selecting any one of an output of the first read section and an output of the second read section according to a mapping type signal to output the selected output to the temporary data storage.

42. The image processing device of claim 36, further comprising a frame/field converter for reading the data transfer units written in the temporary data storage and writing the read data transfer units in the temporary data storage in a field mapping format.

43. The image processing device of claim 36, further comprising a memory arbitrator for establishing a handshake with the first read section and with the first write section, wherein:

after a handshake between the first read section and the memory arbitrator is established, the first read section transfers data transfer units which are to be written in the temporary data storage to the temporary data storage via the memory arbitrator; and

after a handshake between the first write section and the memory arbitrator is established, the first write section receives data transfer units read from the temporary data storage via the memory arbitrator.

44. An imaging system, comprising:

an analog/digital converter for converting an analog image signal to a digital signal; and

an image processing device for performing image processing on the digital signal,

wherein the image processing device includes

a read section for reading pixel data of a two-dimensional image subjected to the image processing and stored in a first image storage and having a plurality of pixels, the position of each of the pixels being represented by coordinates of first and second directions, the pixel data being read by scanning data transfer units of the pixel data in the second direction where each of the data transfer units is formed by data of a predetermined number of pixels consecutive in the first direction, and writing the read data transfer units in a temporary data storage where data is stored at a position designated by a combination of first and second addresses, the data transfer units being written in burst mode in a region of the temporary data storage in which the first addresses are consecutive while the second address is fixed, and

a write section for reading the data transfer units written in the temporary data storage from the region in which the first addresses are consecutive while the second address is fixed in burst mode and writing the read data transfer units in a second image storage.

45. The imaging system of claim 44, further comprising:

a sensor for converting an image to the analog image signal; and

an optical system for forming an input image on the sensor.