PictBridge(DPS) Overview

Bear Lin2009/04/28

Outline

Terminology Introduction Architectural Framework Job Flow Example Main Efforts to Implement PictBridge

Terminology

DPS(Digital Photo Solutions for Image Device) DSC(Digital Still Image Camera) PTP(Picture Transfer Protocol) XML(Extensible Markup Language) DPOF(Digital Print Order Format)

Introduction

CIPA DC-001-2003: Digital Photo Solutions(DPS) for Imaging Devices, Standard of CIPA(Cameras & Imaging Products Association).

“PictBridge” is a promotion name of DPS standard. Main Site:

http://www.cipa.jp/pictbridge/index_e.html

Introduction(cont.)

PictBridge is a smart way to enable direct printing from any PictBridge compliant DSC to any PictBridge compliant printer, regardless of the manufacturer.

Introduction(cont.) PictBridge v.s. DPOF:

DPOF 是一個開放的標準，它支援以下一些列印輸出設置：選擇哪些照片要列印輸出、每張照片列印的份數、列印索引圖片、圖像旋轉、用戶資訊（姓名、地址等等）、圖像資訊（標題、說明）等等。

不過，由於數碼相機和輸出設備的差異性問題，以及一些成本控制的因素，導致目前 DPOF 的應用還只基於一個比較基本的階段，很多高級的功能無法廣泛普及。

比如，目前數碼相機直接連接印表機的功能雖然可以實現，但是卻存在嚴重的相容性問題，即只能同一個品牌的數碼相機和印表機才能實現直聯列印的功能。

因此， 現在 DPOF 逐漸在淡出人們的視線，一個全新的、真正跨品牌的、廣泛的標準——PictBridge 正逐漸取代 DPOF。

http://baike.baidu.com/view/65011.htm http://www.casio.com.tw/qv/dpof/index.html http://www.digital.idv.tw/DIGITAL/Classroom/MROH-CLASS/oh89/index-89.htm

Architectural Framework

The DSC is USB Still Image Capture Class “Device”, and the printer works as a USB “Host”.

USB Device USB I/F USB Host

Architectural Framework(cont.)

DPS architecture is based on Client-Server model. The DSC and the printer must support the Picture

Transfer Protocol(PTP) and the USB.

Architectural Framework(cont.)

DPS actions = a request phase + a response phase, both request/response are well formed XML.

DPS has two kinds of actions: DPS operations and DPS events.

DPS operation: a transaction initiated by the DPS client and completed by the DPS server.

DPS event: a notification from a DPS server to the DPS client. It is initiated when a state change occurs in the server.

Architectural Framework(cont.)

DPS Action Results: For every DPS Action request, a DPS Action result shall be returned along with the DPS Action response.

Architectural Framework(cont.)

DPS’s actions and events are based on PTP.

Each action or event is a sequence of PTP commands.

PTP contains details of Operation, Response, Event and ObjectFormat codes required by the Printer and DSC.

Architectural Framework(cont.)

DPS Print Service Actions:

Architectural Framework(cont.)

DPS Storage Service Actions:

Job Flow Example

Job Flow Example(cont.)

DPS Operation XML script example:

Job Flow Example(cont.)

DPS Operation XML script example:

Job Flow Example(cont.)

DPS Event XML script example:

Main Efforts to Implement PictBridge

Implement DPS over the USB physical layer with the Still Image Capture Device Class PTP protocol.

XML parsers are required because DPS actions will be passed over PTP/USB in their original XML format.