Image processing apparatus and method using plural amounts corresponding to encoded data to control encoding

• US 5,838,826 A
• Filed: 09/30/1994
• Issued: 11/17/1998
• Est. Priority Date: 12/28/1990
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hoshi, Nobuhiro, Enari, Masahiko, Takizawa, Hiroshi
• Primary Examiner(s): Mancuso, Joseph
• Assistant Examiner(s): Patel, Jayanti K.
• Application Number:
  US08/312,942
• Time in Patent Office: 1,509 Days
• Field of Search: 382/232, 382/234, 382/236, 382/246, 382/250, 382/251, 348/405, 358/500
• US Class Current: 382/234
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/126 Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/30 using hierarchical techniques, e.g. scalability H04N19/63 takes precedence
• CPC Class Codes: H04N 19/593 involving spatial prediction techniques
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

An image processing apparatus including: an input device for inputting image data; a first encoding device for encoding the image data with first parameter; a second encoding device for encoding the image data with second parameter; a first counting device for counting the first amount of encoded image data encoded by the first encoding device; a second counting device for counting second amount of encoded image data encoded by the second encoding device; and a calculating device for calculating third parameter, with which the image data is encoded to a predetermined amount of encoded data, in accordance with both of the first and the second amounts of encoded image data.

Claims

1. An image processing apparatus comprising:

input means for inputting image data;

first counting means for counting a first encoded data amount corresponding to first encoded image data encoded by using a first control coefficient which determines the first encoded data amount;

second counting means for counting a second encoded data amount corresponding to second encoded image data encoded by using a second control coefficient which determines the second encoded data amount; and

generating means for generating encoded image data corresponding to the image data input by said input means in accordance with both the first and second encoded data amounts,

wherein said first and second counting means perform counting operations of the first and second encoded data amounts on the same image data in parallel.

2. An image processing apparatus according to claim 1, further comprising determining means for calculating a third control coefficient by using the first encoded data amount and the second encoded data amount.

3. An image processing apparatus according to claim 1, further comprising first and second encoding means each of which includes quantizing means and said control coefficient is a quantizing step.

4. An image processing apparatus according to claim 3, wherein said first and second encoding means perform encoding in parallel.

5. An image processing apparatus according to claim 1, wherein the value of the second control coefficient is larger than that of the first control coefficient and the first amount of encoded image data is larger than the second amount of encoded image data.

6. An image processing method comprising:

an input step of inputting image data;

a first counting step of counting a first encoded data amount corresponding to first encoded image data encoded by using a first control coefficient which determines the first encoded data amount;

a second counting step of counting a second encoded data amount corresponding to second encoded image data encoded by using a second control coefficient which determines the second encoded data amount; and

a generating step of generating encoded image data corresponding to the image data input in said input step in accordance with both the first and second encoded data amounts,

wherein said first and second counting steps are performed for generating the first and second encoded data amounts on the same image data in parallel.

7. An image processing apparatus comprising:

input means for inputting image data;

first encoding means for encoding the image data with a first control coefficient which determines a first encoded data amount;

second encoding means for encoding the image data with a second control coefficient which determines a second encoded data amount;

first counting means for counting the first encoded data amount of image data encoded by said first encoding means;

second counting means for counting the second encoded data amount of image data encoded by said second encoding means; and

generating means for generating encoded image data corresponding to the image data input by said input means,

wherein said generating means has a first mode in which the encoded image data is generated in accordance with both the first and second encoded data amounts and a second mode in which the encoded image data is generated by using a predetermined fixed control coefficient which determines a third encoded data amount.

8. An image processing apparatus according to claim 7, wherein said first and second encoding means perform encoding by employing orthogonal transformation.

9. An image processing apparatus according to claim 7, wherein said first and second encoding means perform encoding in parallel.

10. An image processing apparatus according to claim 7, wherein said input means sequentially inputs a plurality of pictures.

11. An image processing apparatus according to claim 7, further comprising memory means for storing said predetermined fixed parameter.

12. An image processing method comprising:

an input step of inputting image data;

a first encoding step of encoding the image data with a first control coefficient which determines a first encoded data amount;

a second encoding step of encoding the image data with a second control coefficient which determines a second encoded data amount;

a first counting step of counting the first encoded data amount of image data encoded in the first encoding step;

a second counting step of counting the second encoded data amount of image data encoded in the second encoding step; and

a generating step of generating encoded image data corresponding to the image data input by said input step,

wherein said generating step has a first mode in which the encoded image data is generated in accordance with both the first and second encoded data amounts and a second mode in which the encoded image data is generated by using a predetermined fixed control coefficient which determines a third encoded data amount.

13. An image processing apparatus comprising:

input means for inputting image data;

first quantizing means for quantizing the image data with a first quantizing step;

second quantizing means for quantizing the image data with a second quantizing step; and

third quantizing means for quantizing the image data with a third quantizing step,

wherein a difference between said second quantizing step and said third quantizing step is larger than a difference between said first quantizing step and said second quantizing step when the first quantizing step, the second quantizing step and the third quantizing step increase in sequential order.

14. An image processing apparatus according to claim 13 further comprising counting means for counting the amount of image data quantized by said first, second and third quantizing means.

15. An image processing apparatus according to claim 14 further comprising processing means for processing the input data input by said input means in accordance with the amount counted by said counting means.

16. An image processing apparatus according to claim 15, wherein said processing means performs variable-length coding.

17. An image processing method comprising:

an input step of inputting image data;

a first quantizing step of quantizing the image data with a first quantizing coefficient which determines a first quantizing amount;

a second quantizing step of quantizing the image data with a second quantizing coefficient which determines a second quantizing amount; and

a third quantizing step of quantizing the image data with a third quantizing coefficient which determines a third quantizing amount,

wherein a difference between said second quantizing coefficient and said third quantizing coefficient is larger than a difference between said first quantizing coefficient and said second quantizing coefficient on the condition that the first quantizing coefficient, the second quantizing coefficient and the third quantizing coefficient increase in sequential order.

18. An image processing apparatus comprising:

input means for inputting image data;

first counting means for counting a first encoded data amount corresponding to first encoded image data encoded by using a first control coefficient which determines the first encoded data amount;

second counting means for counting a second encoded data amount corresponding to second encoded image data encoded by using a second control coefficient which determines the second encoded data amount; and

determining means for determining a third control coefficient which determines a third encoded data amount, with which the image data is encoded to a predetermined amount of data, by a primary approximation by using the first and second encoded data amounts.

19. An image processing apparatus according to claim 18, further comprising first and second encoding means, each of which includes quantizing means and said control coefficient is a quantizing step.

20. An image processing apparatus according to claim 18, wherein said first and second encoding means perform encoding in parallel.

21. An image processing apparatus according to claim 18, wherein the value of said second control coefficient is larger than that of said first control coefficient and said first amount of encoded image data is larger than said second amount of encoded image data.

22. An image processing method comprising:

an input step of inputting image data;

a first counting step of counting a first encoded data amount corresponding to first encoded image data encoded by using a first control coefficient which determines the first encoded data amount;

a second counting step of counting a second encoded data amount corresponding to second encoded image data encoded by using a second control coefficient which determines the second encoded data amount;

a determining step of determining a third control coefficient which determines a third encoded data amount, with which the image data is encoded to a predetermined amount of data, by a primary approximation by using the first and the second encoded data amounts.

23. An image processing apparatus comprising:

input means for inputting image data;

first counting means for counting a first encoded data amount corresponding to first encoded image data encoded by using a first encoding control coefficient which determines the first encoded data amount;

second counting means for counting a second encoded data amount corresponding to second encoded image data encoded by using a second encoding control coefficient which determines the second encoded data amount; and

generating means for generating encoded image data corresponding to the image data input by said input means,

wherein said generating means has a first mode in which the encoded image data is generated in accordance with both the first and second encoded data amounts and a second mode in which the encoded image data is generated by using a predetermined fixed control coefficient which determines a third encoded data amount.

24. An image processing apparatus according to claim 23, wherein said generating means performs the encoding by employing an orthogonal transformation.

25. An image processing apparatus according to claim 23, wherein said first and second counting means perform the counting in parallel.

26. An image processing apparatus according to claim 23, wherein said input means sequentially inputs a plurality of pictures.

27. An image processing apparatus according to claim 23, further comprising memory means for storing the predetermined fixed control coefficient.

28. An image processing method comprising:

an input step of inputting image data;

a first counting step of counting a first encoded data amount corresponding to first encoded image data encoded by using a first encoding control coefficient which determines the first encoded data amount;

a second counting step of counting a second encoded data amount corresponding to second encoded image data encoded by using a second encoding control coefficient which determines the second encoded data amount; and

a generating step of generating encoded image data corresponding to the image data input by said input step,

wherein said generating step has a first mode in which the encoded image data is generated in accordance with both the first and second encoded data amounts and a second mode in which the encoded image data is generated by using a predetermined fixed control coefficient which determines a third encoded data amount.