Image forming system

• US 5,642,208 A
• Filed: 11/18/1994
• Issued: 06/24/1997
• Est. Priority Date: 11/22/1993
• Status: Expired due to Term

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Takahashi, Hiroyuki, Kitamura, Toshiyuki, Kurita, Mitsuru
• Primary Examiner(s): Coles, Sr., Edward L.
• Assistant Examiner(s): LEE, CHEUKFAN
• Application Number:
  US08/344,596
• Time in Patent Office: 949 Days
• Field of Search: 358/515, 358/500, 358/501, 358/502, 358/503, 358/524, 358/527, 358/400, 358/401, 358/402, 358/403, 358/404, 358/444, 358/442, 358/468, 358/296, 382/166, 382/167, 395/114, 395/115, 395/116, 395/164, 395/166, 355/202
• US Class Current: 358/501
• CPC Class Codes: H04N 1/32443 with asynchronous operation of the image input and output devices connected to the memory
• CPC Class Codes: H04N 1/506 Reproducing the colour component signals picture-sequentially, e.g. with reproducing heads spaced apart from one another in the subscanning direction
• CPC Class Codes: H04N 1/648 Transmitting or storing the primary (additive or subtractive) colour signals; Compression thereof H04N1/642 - H04N1/646 take precedence

Abstract

An image forming system includes a plurality of sequentially connected image forming apparatuses, each of which stores image data in a storage unit, and forms an image by reading out the stored image data. The image forming system also includes at least an apparatus for storing input image data into a memory after compressing the information amount of the data, and forming an image by reading out the compressed image data from the memory. A predetermined one of the image forming apparatuses includes an input unit for inputting color-separated image data of each different color, a storage unit for storing the color-separated image data without compressing the information amount of the data, and an output unit which is capable of outputting the color-separated image data of each different color in a frame-sequential manner from the storage unit, and which is capable of outputting the color-separated image data of each different color in parallel. This arrangement results in the memory capacity of the entire system being decreased while maintaining a high copy volume.

Claims

1. An image forming system constituted by connecting a plurality of image forming apparatuses each for storing image data in storage means and forming an image, wherein

a predetermined one of said image forming apparatuses comprises:

(a) input mean for inputting color-seperated image data of each different color in a sequential manner and for inputting in parallel the color-separated image data of each different color;

(b) storage means for storing the input image data input by said input means;

(c) data compressing means for data compressing the image data stored in said storage means; and

(d) transfer means for transferring the image data compressed by said compressing means to said image forming apparatuses.

2. A system according to claim 1, wherein each of said image forming apparatuses except for said predetermined apparatus has expanding means for expanding the information amount of the compressed image data.

3. A system according to claim 1, wherein said predetermined apparatus has processing means for performing predetermined processing for the input image data and is capable of changing the processing in accordance with an input form of the input image data.

4. A system according to claim 3, wherein

said input means also inputs additional information indicating a form of the image data, and

said processing means changes the processing in accordance with the additional information.

5. A system according to claim 1, wherein

said predetermined apparatus has memory connecting means for connecting an image memory unit, and

said system can transfer image data read out from said image memory unit connected by said memory connecting means parallelly to said image forming apparatuses connected to said system.

6. An image forming apparatus usable in an image forming system constituted by connecting a plurality of image forming apparatuses each for forming an image, comprising:

(a) input means for inputting color-separated image data of each different color in a sequential manner and for inputting in parallel the color-separated image data of each different color;

(b) storage means for storing the input image data; and

(c) data compressing means for data compressing the image data stored in said storage means; and

(d) transfer means for transferring the image data compressed by said compressing means to said image forming apparatuses.

7. An apparatus according to claim 6, wherein said storage means includes a plurality of memories and memory control means.

8. An apparatus according to claim 7, wherein, when the image data of each different color are input in a frame-sequential manner, said storage means sequentially stores each image data into a corresponding one of said memories, and, when the image data of each different color are input parallelly, said storage means stores the image data parallelly into said memories and reads out the image data parallelly.