Printer controller and system having a DMA data transmission

• US 7,528,980 B2
• Filed: 10/28/2005
• Issued: 05/05/2009
• Est. Priority Date: 10/15/1999
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Tanaka, Tomonori
• Primary Examiner(s): Poon; King Y
• Assistant Examiner(s): Cruz; Iriana
• Application Number:
  US11/260,206
• Publication Number:
  US 20060039032A1
• Time in Patent Office: 1,285 Days
• Field of Search: 358/1.1, 358/1.15, 358/1.9, 358/3, 358/3.25, 358 326- 329, 346/107.3, 709/247
• US Class Current: 358/1.15
• CPC Class Codes: H04N 1/00204 with a digital computer or a digital computer system, e.g. an internet server programmed control between transmitter and receiver or between image input and image output device H04N1/32561
• CPC Class Codes: H04N 1/00347 with another still picture apparatus, e.g. hybrid still picture apparatus circuits or arrangements for control or supervision between image input and image output device H04N1/32
• CPC Class Codes: H04N 1/32502 in systems having a plurality of input or output devices
• CPC Class Codes: H04N 1/32529 of different type, e.g. internal and external devices
• CPC Class Codes: H04N 1/32598 Bus based systems
• CPC Class Codes: H04N 1/3333 during transmission, input or output of the picture signal; within a single document or page
• CPC Class Codes: H04N 2201/0081 Image reader H04N2201/0091 - H04N2201/0094 take precedence
• CPC Class Codes: H04N 2201/0082 Image hardcopy reproducer H04N2201/0091 - H04N2201/0094 take precedence
• CPC Class Codes: H04N 2201/3287 Storage of at least one complete document page or image frame
• CPC Class Codes: H04N 2201/33357 Compression mode

Abstract

A printer controller and system that include a descriptor storing device which stores descriptor information, an image memory which stores at least one of encoded image data and non-encoded image data, a decoding device which decodes encoded image data, a first data path which transmits the encoded image data stored in the image memory to an external device via the decoding device, and a second data path which transmits the non-encoded image data stored in the image memory to the external device. The printer controller and system further include a direct memory access (DMA) control device that controls the image data stored in the image memory so as to be transmitted via one of the first data path and the second data path according to the descriptor information stored in the descriptor storing device.

Claims

1. A printer controller comprising:

a descriptor storing device configured to store descriptor information including the compression ratio of encoded image data;

an image memory configured to store encoded image data and non-encoded image data;

a decoding device configured to decode encoded image data;

a first data path configured to transmit the encoded image data stored in the image memory to an external device via the decoding device;

a second data path configured to transmit the non-encoded image data stored in the image memory to the external device without passing through the decoding device; and

a direct memory access (DMA) control device configured and connected to control the image data stored in the image memory so as to be transmitted via one of the first data path and the second data path according to the descriptor information including the compression ratio of encoded image data stored in the descriptor storing device.

2. The printer controller according to claim 1, wherein the DMA controls the image data stored in the image memory so as to be transmitted via the second data path when the compression ratio of the encoded image data is greater than one.