Image processing apparatus for performing compression of image data based on serially input effective size data

• US 5,757,965 A
• Filed: 10/04/1994
• Issued: 05/26/1998
• Est. Priority Date: 11/19/1990
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ohki, Joji
• Primary Examiner(s): Coles, Sr., Edward L.
• Assistant Examiner(s): Williams, Kimberly A.
• Application Number:
  US08/317,460
• Time in Patent Office: 1,330 Days
• Field of Search: 358/449, 358/404, 358/426, 358/444, 358/453, 358/451, 358/448, 358/468, 358/432, 358/433, 382/56, 382/305, 382/232, 382/239, 382/166
• US Class Current: 382/232
• CPC Class Codes: H04N 1/33323 transmission mode only, e.g. speed
• CPC Class Codes: H04N 19/00 Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
• 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 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/91 Entropy coding, e.g. variable length coding [VLC] or arithmetic coding
• CPC Class Codes: H04N 2201/33321 Image or page size, e.g. A3, A4
• CPC Class Codes: H04N 2201/33357 Compression mode

Abstract

An image processing apparatus discriminates an effective size of input image data, compresses the input image data, and controls the compression in accordance with the discriminated effective size.

Claims

1. An image processing apparatus which receives compressed image data and can store the compressed image data in storing means, comprising:

discriminating means for discriminating a data size of the compressed image data before said storing means stores the compressed image data;

means for expanding the received compressed image data when it is determined that the data size of the compressed image data discriminated by said discriminating means is larger than an effective size of said storing means; and

compressing means for recompressing the image data expanded by said expanding means so that it can be stored in said storing means.

2. An apparatus according to claim 1, further comprising means for supplying the compressed data stored in said storing means to a printer.

3. An apparatus according to claim 2, wherein recompression is achieved by said compressing means by controlling compressing state by means of controlling a quantization value to quantize the data after completion of an orthogonal transformation.

4. An image processing system comprising;

means for inputting image information;

first compressing means for compressing image data corresponding to the image information input by said inputting means;

discriminating means for discriminating a data size of the compressed image data produced by said first compressing means;

means for expanding the received compressed image data when it is determined that the data size of the compressed image data discriminated by said discriminating means is larger than an effective size of a storing means; and

second compressing means for compressing the image data expanded by said expanding means so that it can be stored in the storing means.

5. A system according to claim 4, further comprising a second expanding means for expanding compressed image data stored in the storing means.

6. A system according to claim 5, further comprising means for supplying image data expanded by said said second expanding means to an image forming device.

7. A system according to claim 6, wherein the image forming device is a printer.

8. A system according to claim 7, wherein the printer is a printer which discharges a liquid.

9. A system according to claim 8, wherein the printer discharges the liquid by causing a film boiling due to thermal energy.

10. A system according to claim 4, wherein the compressed image data is compressed multivalue image data.