SIST-TS CEN/TS 15448:2015
(Main)Postal services - Open standard interface between image controller and enrichment devices (OCRs, video coding systems, voting systems)
Postal services - Open standard interface between image controller and enrichment devices (OCRs, video coding systems, voting systems)
The purpose of this Technical Specification is to define the requirements of the OCR/VCS Standard interface and to convey these requirements in context to the reader.
This document is arranged under 4 main clauses as described in Figure 1:
- UCM (Use Case Model) describes the use cases for the IC/ED Interface using sequence diagrams with messages.
- IDD (Interface Design Description) defines the data model for the IC/ED interface.
- SDD (System Design Description) defines the mandatory specification of the IC/ED interface in terms of architecture, services and behavioural models. In the Common Part of this clause no middleware or transport layer is specified. The common part of this clause is intended to be middleware-independent.
- SDD-TCP/IP, SDD-CORBA, in these specialized clauses. The specifications for 2 compatible transport solutions TCP/IP, CORBA are provided. Further middleware solutions (such as SOAP) can be added when available, provided that they are fully compatible with the Common Part.
As shown on Figure 2, there are many interfaces from an Enrichment Device to the rest of the system. This document is only concerned with the Mailpiece Processing part of the complete Standard Interface.
The mailpiece processing is concerned with the passing of a mailpiece to an Enrichment Device for processing.
Figure 3 depicts the system model of an Enrichment Device. As visible on the figure, an Enrichment Device is one of:
- an OCR:
a single or a pool of automatic recognition and interpretation engines, which are capable of retrieving information from an image of a mailpiece without human intervention;
- a VCS:
a single or a pool of video coding desks, which produce results from images of mailpieces; all tasks related to the management of the coders and the coding desks are encapsulated within the VCS system, or are accessible via interfaces which are outside the scope of the interface described within this document;
- a Voter:
a system which can determine the most appropriate result for a mailpiece using data and/or an image of a mailpiece; typically, a voter determines the most appropriate result from two or more results.
This document therefore covers the Mailpiece Processing interface between the Image Controller and the Enrichment Devices.
The document describes the requirements in the case of real-time enrichment: operational mode of an Enrichment Device, where the ED replies within the specified expiration time to the IC; the IC has to keep track of all mailpieces waiting for a reply from an ED. The ED does not keep persistence of mailpieces outside a channel connection with the IC. The ED has to have the processing power available to enrich a mailpiece. There is one and only one response for a mailpiece.
A later version of the document shall describe the case of deferred enrichment: operational mode of an Enrichment Device, where the ED may pre-request mailpieces from the IC. The ED has to keep persistence of the mailpiece to enrich it later and keep the result available for a result request from the IC. There is no response expected by IC from the ED.
The interface between Image Controller and Image Controller is NOT part of this document.
Furthermore, there may be many IC connected to many ED’s, as shown in the following object model:
The submission strategy in case of one IC connected to many ED’s is not part of the interface. It is for optimizing the mail flow in case of identical ED’s, or for defining the order in which different ED’s are activated (cascaded versus parallel submission).
The submission strategy of the IC shall be part of the specification and certification of the IC, which is not part of this document.
Postalische Dienstleistungen - Offene Normschnittstelle zwischen Bildbearbeitung und Anreicherungsgeräten (OCR, Videocodierungssystem, Abstimmungssysteme)
Services postaux - Interface standard ouverte entre le contrôleur d’images et les dispositifs enrichis (OCR, systèmes d’encodage vidéo, systèmes de votes)
Poštne storitve - Odprti standardni vmesnik med obdelovalnikom slike in napravami za obogatitev (optično prepoznavanje znakov (OCR), sistemi za videokodiranje, glasovalni sistemi)
Namen tega tehničnega poročila je določiti zahteve za vmesnik standarda OCR/VCS in te zahteve bralcu podati v kontekstu.
Ta dokument je razdeljen v 4 glavne točke, kot je opisano na sliki 1:
– UCM (model primerov uporabe) opisuje primere uporabe za vmesnik IC/ED na podlagi diagramov zaporedij s sporočili.
– IDD (opis zasnove vmesnika) določa podatkovni model za vmesnik IC/ED.
– SDD (opis zasnove sistema) določa obvezno specifikacijo vmesnika IC/ED v smislu arhitekture, storitev in vedenjskega modela. V splošnem delu te točke ni določena nobena vmesniška programska oprema ali transportna plast. Splošen del te točke naj bi bil neodvisen od vmesniške programske opreme.
– SDD-TCP/IP, SDD-CORBA, v teh specializiranih točkah. Zagotovljene so specifikacije za dve združljivi transportni rešitvi TCP/IP, CORBA. Dodatne rešitve vmesniške programske opreme (kot je SOAP) se lahko dodajo, ko so na voljo, če so v celoti združljive s splošnim delom.
(...)
Kot je prikazano na sliki 2, obstaja veliko vmesnikov od naprave za obogatitev do preostalega dela sistema. V tem dokumentu je obravnavan le del celotnega standardnega vmesnika, povezan z obdelavo pošiljk.
Obdelava pošiljk vključuje pošiljanje pošiljk v obdelavo v napravo za obogatitev.
(...)
Na sliki 3 je prikazan model sistema naprave za obogatitev. Iz slike je razvidno, da je lahko naprava za obogatitev:
– OCR:
ena sama naprava ali skupina naprav za samodejno prepoznavanje in razlago znakov, ki lahko pridobi informacije s slike pošte brez človeškega posega;
– VCS:
ena sama miza za video kodiranje ali skupina miz za video kodiranje, ki pripravi rezultate na podlagi slik pošiljk; vse naloge, povezane z upravljanjem kodirnikov in kodirnih miz so enkapsulirane v sistemu VCS ali so dostopne prek vmesnikov, ki ne spadajo v področje uporabe vmesnika, opisanega v tem dokumentu;
– sistem Voter:
sistem, ki lahko določi najustreznejši rezultat za pošiljko z uporabo podatkov in/ali slike pošiljke; običajno sistem Voter izbere najustreznejši rezultat na podlagi dveh ali več rezultatov.
Ta dokument torej ne zajema vmesnika za obdelavo pošiljk med kontrolnikom slike in napravami za obogatitev.
V tem dokumentu so opisane zahteve v primeru sprotne obogatitve: način delovanja naprave za obogatitev, pri katerem naprava v določenem času odgovori kontrolniku slike; kontrolnik slike mora spremljati vse pošiljke, ki čakajo na odgovor naprave za obogatitev. Naprava za obogatitev ne hrani pošiljk zunaj povezovalnega kanala s kontrolnikom slike. Naprava za obogatitev mora imeti na voljo obdelovalno moč za obogatitev pošiljke. Za posamezno pošiljko je mogoč le en odziv.
V poznejši različici dokumenta je treba opisati primer odložene obogatitve: način delovanja naprave za obogatitev, pri katerem lahko naprava predhodno zahteva pošiljke iz kontrolnika slike. Naprava za obogatitev mora hraniti pošiljko za poznejšo obogatitev in shraniti rezultat, ki bo na voljo na zahtevo kontrolnika slike. Kontrolnik slike ne pričakuje odziva iz naprave za obogatitev.
Vmesnik med kontrolniki slike NI del tega dokumenta.
Poleg tega je lahko več kontrolnikov slike povezanih z več napravami za obogatitev, kot je prikazana na naslednjem predmetnem modulu.
(...)
Strategija predložitve, ki se uporabi, če je en kontrolnik slike povezan z več napravami za obogatitev, ni del vmesnika. Gre za optimizacijo toka pošte v primeru enakih naprav za obogatitev ali za opredelitev vrstnega reda aktivacije različnih naprav za obogatitev (postopna ali istočasna predložitev).
Strategija predložitve kontrolnika slike je del specifikacije in certifikacije kontrolnika slike, ki ni del tega dokumenta.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-marec-2015
1DGRPHãþD
SIST-TS CEN/TS 15448:2007
SIST-TS CEN/TS 15448:2007/AC:2009
3RãWQHVWRULWYH2GSUWLVWDQGDUGQLYPHVQLNPHGREGHORYDOQLNRPVOLNHLQ
QDSUDYDPL]DRERJDWLWHY RSWLþQRSUHSR]QDYDQMH]QDNRY 2&5 VLVWHPL]D
YLGHRNRGLUDQMHJODVRYDOQLVLVWHPL
Postal services - Open standard interface between image controller and enrichment
devices (OCRs, video coding systems, voting systems)
Postalische Dienstleistungen - Offene Normschnittstelle zwischen Bildbearbeitung und
Anreicherungsgeräten (OCR, Videocodierungssystem, Abstimmungssysteme)
Services postaux - Interface standard ouverte entre le contrôleur d’images et les
dispositifs enrichis (OCR, systèmes d’encodage vidéo, systèmes de votes)
Ta slovenski standard je istoveten z: CEN/TS 15448:2014
ICS:
03.240 Poštne storitve Postal services
35.240.69 Uporabniške rešitve IT pri IT applications in postal
poštnih storitvah services
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
TECHNICAL SPECIFICATION
CEN/TS 15448
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
December 2014
ICS 03.240; 35.240.60 Supersedes CEN/TS 15448:2006
English Version
Postal services - Open standard interface between image
controller and enrichment devices (OCRs, video coding systems,
voting systems)
Services postaux - Interface standard ouverte entre le Postalische Dienstleistungen - Offene Normschnittstelle
contrôleur d'images et les dispositifs enrichis (OCR, zwischen Bildbearbeitung und Anreicherungsgeräten (OCR,
systèmes d'encodage vidéo, systèmes de votes) Videocodierungssysteme, Abstimmungssysteme)
This Technical Specification (CEN/TS) was approved by CEN on 15 March 2014 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 15448:2014 E
worldwide for CEN national Members.
Contents Page
Foreword .4
Introduction .5
1 Scope .6
2 Normative references .9
3 Terms and definitions .9
4 Symbols and abbreviations . 11
5 The Use Case Model (UCM) . 11
5.1 General . 11
5.2 Overall Description . 12
5.2.1 General . 12
5.2.2 Use-Case Model Survey . 12
5.2.3 Assumptions and Dependencies . 15
5.3 Specific Requirements . 22
5.3.1 Use-Case Reports . 22
5.3.2 Supplementary Requirements . 45
5.3.3 Rejections . 45
6 Interface Design Description IDD . 46
6.1 Purpose . 46
6.2 Scope of IDD . 47
6.3 Prerequisites . 47
6.4 Overview . 47
6.5 Section A – TIFF Definition . 48
6.5.1 Tiff Usage . 48
6.6 Section B – Mailpiece Data Definition . 53
6.6.1 Requirements . 53
6.6.2 Model Commitments . 57
6.6.3 Domain Data Model & Types . 58
7 System Design Description (SDD) – Common Part . 132
7.1 Purpose . 132
7.2 Overview . 133
7.3 Architectural Goals and Constraints . 133
7.3.1 General . 133
7.3.2 Client Server Model . 134
7.3.3 Client / Servant Relationships . 134
7.3.4 Server Selection . 136
7.4 Service Model . 137
7.4.1 Overview . 137
7.4.2 Exception Handling . 139
7.4.3 Logical link between IC and ED services . 139
7.4.4 Interface: IEnrichmentDevice . 139
7.4.5 Interface: IImageController . 143
7.4.6 Data definition . 147
7.5 Behavioural Model . 147
8 System Design Description (SDD) – Middleware dependent parts . 148
8.1 SDD TCP/IP Implementation . 148
8.1.1 Communication layer . 148
8.1.2 Server selection . 149
8.1.3 Message definition . 149
8.1.4 Behavioural Model . 151
8.2 SDD CORBA Implementation . 167
8.2.1 General . 167
8.2.2 Server Selection . 167
8.2.3 Exception Handling . 169
8.2.4 ORB Implementation . 169
8.2.5 Interface Definition . 169
8.2.6 Behavioural Model . 172
8.3 SDD SOAP Implementation . 199
Annex A (informative) Introduction to XML . 200
A.1 Introduction to XML . 200
A.1.1 General . 200
A.1.2 XML Document Structure . 200
A.1.3 Introduction to XML Schema . 201
A.2 XML Schemas . 203
A.2.1 Domain Instance Types . 203
A.2.2 Base Types . 209
A.2.3 Generic Types . 217
A.2.4 Primitives. 219
A.2.5 Example of a Customer specific Schema Definition . 223
A.3 The XML Instance Document . 225
A.3.1 Type Assignment in the Instance Document. 225
A.3.2 Examples . 226
Bibliography . 237
Foreword
This document (CEN/TS 15448:2014) has been prepared by Technical Committee CEN/TC 331 “Postal
services”, the secretariat of which is held by NEN.
The document supersedes CEN/TS 15448:2006.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus,
Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Introduction
There is a growing demand on the postal operators to combine parts of their sorting automation equipment
from different suppliers to optimize performance. In the past this has led to project specific interfaces being
negotiated between one postal operator and one or multiple suppliers. These project-specific interfaces were
developed by the suppliers and maintained for an agreed period of time. This approach has several
disadvantages:
— The interface is derived from an interface that was not intended to be open,
— The interface is developed for a single project and works only in the context of that project (extra costs),
— Each participating supplier has to implement the interface (multiple effort),
— Experience shows that integration of components with project-specific interfaces is complex and
expensive,
— Project-specific interfaces are not integrated into the product line and once the initially agreed
maintenance period is over it may be difficult and expensive to maintain and/or may hinder the adoption
of equipment upgrades.
This has led to “open interfaces” defined by one supplier. These still have the disadvantage of being in
product use by only one supplier.
Within a group of postal operators and suppliers it was decided to develop a set of “open standard interfaces”
which will be developed by the suppliers and referred to by the postal operators. The benefits of these
interfaces are expected to be that they:
— are fixed in an international standard (with change control);
— are agreed and implemented by major suppliers;
— are agreed by customers and therefore used in calls for tenders;
— will result in net savings with the high initial development effort and consequent higher basic equipment
prices being more than offset by reduced project development, integration and maintenance costs;
— will minimize the need for project integration effort by reducing implementation timescales;
— will increase competition between suppliers by stimulating product improvements.
This document covers the interface between an image controller and so called enrichment devices (OCR,
Video Coding System or Voting System).
The communication partners of this interface will be called Image Controller (IC) on the one side and
Enrichment Device (ED) on the other side.
Other work items (subject to agreement of CEN/TC331 and the UPU Standards Board) will be defined to
cover other areas as and when the need is identified and the resources for development become available. A
separate project group for each interface will undertake the work.
1 Scope
The purpose of this Technical Specification is to define the requirements of the OCR/VCS Standard interface
and to convey these requirements in context to the reader.
This document is arranged under 4 main clauses as described in Figure 1:
— UCM (Use Case Model) describes the use cases for the IC/ED Interface using sequence diagrams with
messages.
— IDD (Interface Design Description) defines the data model for the IC/ED interface.
— SDD (System Design Description) defines the mandatory specification of the IC/ED interface in terms of
architecture, services and behavioural models. In the Common Part of this clause no middleware or
transport layer is specified. The common part of this clause is intended to be middleware-independent.
— SDD-TCP/IP, SDD-CORBA, in these specialized clauses. The specifications for 2 compatible transport
solutions TCP/IP, CORBA are provided. Further middleware solutions (such as SOAP) can be added
when available, provided that they are fully compatible with the Common Part.
Figure 1 — IC/ED Interface Document Structure
Figure 2 — Interface environment of an Enrichment Device
As shown on Figure 2, there are many interfaces from an Enrichment Device to the rest of the system. This
document is only concerned with the Mailpiece Processing part of the complete Standard Interface.
The mailpiece processing is concerned with the passing of a mailpiece to an Enrichment Device for
processing.
Figure 3 — System model
Figure 3 depicts the system model of an Enrichment Device. As visible on the figure, an Enrichment Device is
one of:
— an OCR:
a single or a pool of automatic recognition and interpretation engines, which are capable of retrieving
information from an image of a mailpiece without human intervention;
— a VCS:
a single or a pool of video coding desks, which produce results from images of mailpieces; all tasks related to
the management of the coders and the coding desks are encapsulated within the VCS system, or are
accessible via interfaces which are outside the scope of the interface described within this document;
— a Voter:
a system which can determine the most appropriate result for a mailpiece using data and/or an image of a
mailpiece; typically, a voter determines the most appropriate result from two or more results.
This document therefore covers the Mailpiece Processing interface between the Image Controller and the
Enrichment Devices.
The document describes the requirements in the case of real-time enrichment: operational mode of an
Enrichment Device, where the ED replies within the specified expiration time to the IC; the IC has to keep
track of all mailpieces waiting for a reply from an ED. The ED does not keep persistence of mailpieces outside
a channel connection with the IC. The ED has to have the processing power available to enrich a mailpiece.
There is one and only one response for a mailpiece.
A later version of the document shall describe the case of deferred enrichment: operational mode of an
Enrichment Device, where the ED may pre-request mailpieces from the IC. The ED has to keep persistence of
the mailpiece to enrich it later and keep the result available for a result request from the IC. There is no
response expected by IC from the ED.
The interface between Image Controller and Image Controller is NOT part of this document.
Furthermore, there may be many IC connected to many ED’s, as shown in the following object model:
Figure 4 — Communication relationship between IC and ED
The submission strategy in case of one IC connected to many ED’s is not part of the interface. It is for
optimizing the mail flow in case of identical ED’s, or for defining the order in which different ED’s are activated
(cascaded versus parallel submission).
The submission strategy of the IC shall be part of the specification and certification of the IC, which is not part
of this document.
2 Normative references
Not applicable.
3 Terms and definitions
For the purposes of his document, the following terms and definitions apply.
3.1
actor
coherent set of roles those users of uses cases play when interacting with these use cases.
Note 1 to entry: An actor has one role for each use case with which it communicates. See [UML].
3.2
attributes
non-image information related to a mailpiece
3.3
coding desk
computer or terminal equipped with a software to display images of mailpieces, and designed for a human
operator (video coder) to enter information about the mailpiece
3.4
component
software unit with a defined interface; might contain other components
3.5
data element
simple data type
3.6
data object
assembly of elements [1.*] and/or other data objects; recursive type
3.7
enrichment
process of generating new information about a mailpiece
Note 1 to entry: Any information about the mailpiece may be used in this process, such as the image, image
information or result data. However, the use of an image is not compulsory.
3.8
enrichment device
ED
system designed to enrich information about mailpieces
3.9
flow control
principle of sending images of mailpieces from an IC to an ED: either on request of the ED (“request” mode),
or at a pace defined by the IC, with emission suspended/resumed on request by the ED
3.10
image
data acquired by the Image Supply and stored as part of the mailpiece
3.11
image controller
IC
system designed to handle the flow of images and data issued by the Image Supplies and sent to the
Enrichment Devices
Note 1 to entry: The Image Controller also controls the results from image enrichment.
3.12
infrastructure data
basic information, such as identification references which an Image Controller and Enrichment Device require
in order to communicate effectively
EXAMPLE Letter ID, Submission ID.
3.13
mail object
letter, Flat, Parcel, Postcard etc.
3.14
mailpiece
information stored about a single physical mail item (letter, flat or parcel) in an IC
3.15
mailpiece data
information which describes attributes of the physical mailpiece which is used to aid and is a product of
enrichment
EXAMPLE Mailpiece width & height, indicia information, address location, city name, sort code, etc.
3.16
offline
operational mode of a sorting machine, in which some processing of mail is done after the mail has been
nd
conveyed in the machine; there is a need for printing an ID-tag, to identify the mail for which a 2 sorting pass
is required
3.17
online
operational mode of a sorting machine, implying all the processing of mail is done while the mail is conveyed
in the machine; there is no need for printing an ID-tag
3.18
permanent Error
fatal error as indicated by the middleware or application layer.
Note 1 to entry: A non-fatal error may be considered to be a permanent error after repeated remedial handling.
3.19
result
outcome of enrichment
3.20
street
street keying (street name and/or house number in street)
3.21
system
components and relationships between these (interfaces, communication)
3.22
voter
system which can determine the most appropriate result for a mailpiece using data and/or an image of a
mailpiece
4 Symbols and abbreviations
ED Enrichment Device
GUI Graphical User Interface
IC Image Controller
ID Identifier
IDD Interface Design Description
OCR Optical Character Recognition
PC Post code
PM Project Manager
ROI Region Of Interest
SDD System Design Description
UCM Use Case Model
VCS Video Coding System
W3C World Wide Web Consortium
XML eXtendable Markup Language
CORBA Common Object Request Broker
TCP/IP Transmission Control Protocol/Internet Protocol
SOAP Simple Object Access Protocol
5 The Use Case Model (UCM)
5.1 General
The Use Case Model (UCM) defines the requirements of the CEN OCR/VCS Standard interface. The
document utilizes UML use cases and other modelling techniques as well as textual information to convey the
requirements.
This clause contains the following sections:
— Overall Description:
the use case model for the installation is described;
— Specific Requirements:
the use cases are described in detail including all supplementary requirements.
5.2 Overall Description
5.2.1 General
Unified Modelling Language has been used to describe the use case model. Details of UML can be found in
[UML_OES], [UML_ALH] and [UML].
5.2.2 Use-Case Model Survey
5.2.2.1 General
The Use Case Model is separated into two groups of use cases: those which are relevant for the connection
to an Enrichment Device system, and those which are relevant for managing and using a channel.
5.2.2.2 Connection Use Case Model
5.2.2.2.1 General
The connection use cases (Figure 5) apply to the Enrichment Device as a complete component. They enable
a connection to be established and channels to be opened as well as the status exchange of the complete
Enrichment Device.
Figure 5 — Connection use cases
5.2.2.2.2 Actors
Name Description
Image Software: The Image Controller is a complete software system which is possibly made up of
Controller many software components deployed on multiple hardware nodes. The IC is responsible for
distributing images from the image sources to the Enrichment Devices and handling the
results which are generated. The IC is responsible for the strategy for distributing the
images.
Customer Human: The Customer actor is a human who is able to start and stop the components.
Timer Software: A timer which triggers events at defined intervals.
5.2.2.2.3 Use Cases
ID Name Description
UC001 Publish Presence The Enrichment Device presents is presence to the Image Controller
when it is switched on. Following strict client-server rules, the ED (the
server) is passive and is connected-to by an IC (client).
UC002 Connect The IC detects an ED which it wishes to utilize for processing mailpieces.
It connects to the ED in order to use the processing capabilities of the
ED. During the connection, the capabilities of the ED are exchanged with
the IC.
UC003 Disconnect A disconnect is bi-directional. A disconnect implies closing any opened
channel within the connection
UC004 Open Channel The Image Controller opens a coding channel.
A channel defines the subset of the published capabilities
The flow control is related to a channel.
UC005 Put ED Status 1)
The ED indicates to the IC any relevant data about its status
UC006 Get ED Status The IC needs to know the global status of ED:
to be able to go further in the transactions
to display the status of the ED on the IC’s GUI
5.2.2.3 Channel Use Case Model
5.2.2.3.1 General
These use cases (Figure 6) apply to a channel which has been previously opened. They allow the closing of a
channel, the processing of mailpieces and the exchange of the channel status.
1) Deleted: This use case describes a message and not a use case. Remove this UC because the aims of the message
can be covered by a) ED disconnects from IC is covered in UC - Disconnect. B) The need for the ED to know if the IC is
present, can be fulfilled by checking if "Get ED Status" is executed or by observing its channels.
Figure 6 — Channel use cases
5.2.2.3.2 Actors
Name Description
Image Software: The Image Controller is a complete software system which is possibly made up of
Controller many software components deployed on multiple hardware nodes. The IC is responsible for
distributing images from the image sources to the Enrichment Devices and handling the
results which are generated. The IC is responsible for the strategy for distributing the
images.
Disconnect Use Case : See UC003 - Disconnect
State Software: In a “real-time” processing environment the Enrichment Device shall have the
Manager ability to control the flow of images which is receives from the IC. This actor is used to
represent the capacity of the ED. . When this capacity of the channel is exhausted, the flow
of images from the IC is stopped and vice-versa.
5.2.2.3.3 Use Cases
ID Name Description
UC101 Close Channel Close the channel and optionally discard any pending work
UC102 Control Flow Control the flow of mailpieces from the Image Controller. See 5.2.3.11,
Flow Control Model.
UC103 Request Channel The IC requests from the ED any relevant data to manage a channel
Status
UC104 Submit Mailpiece A mailpiece is submitted to the ED for processing.
UC105 Transmit Result A result is transmitted from the ED to the IC for every mailpiece which
was previously submitted.
5.2.3 Assumptions and Dependencies
5.2.3.1 Image supply
Image supply is to be understood as a resource of images. Images might come from:
— Image capturing devices;
— Fed via network or from an image server;
— Other systems that can supply images.
5.2.3.2 Control
The Image Controller (IC) handles the flow of images and data. It also controls the results from image
enrichment. If parts of an image are distributed to different Enrichment Devices it is the task of the IC to keep
track of these parts and collect the returned data.
— There may be more than one ED connected to an IC.
— There may be more than one IC connected to an ED.
5.2.3.3 Output
The enrichment will produce results, which have to be delivered to other systems. This would normally be
sorting machines or statistical systems.
5.2.3.4 Enrichment
This part of the system enriches the mail piece data. This might be done by Video Coding, OCR or Voters.
The interface described in this document should allow for parts of an image to be distributed.
EXAMPLE The stamp region might be sent to a special stamp reader or the address region to an address reader.
5.2.3.5 Data Representation
Only image relevant data will be stored within the TIFF image. All postal data (mailpiece attributes) will be
transferred using XML. Infrastructure data needed for communication between IC and ED will be transferred,
not necessarily in XML – see Clause 6 for more detail.
Mailpiece attributes (in XML), image (in TIFF), and infrastructure data are transmitted together, excluding:
— embedding XML in TIFF
— embedding TIFF in XML
— referencing of the image in the XML data
Transferring images by reference shall be evaluated in a later version of the interface; this is not done in the
current version of interface for following reasons:
— need to define the protocol for referencing
— added complexity of the interface: need to add a GetImage use case as an alternative flow of
SubmitMailpiece
— added complexity of the interface to handle error cases, like ED failing to access the image
However, the need for transferring by reference exists:
— it may allow to reduce the network load within the ED
— it may allow to transmit different images (binary, greyscale, ROI…) depending on recognition step
5.2.3.6 Image Representation
All images are represented using the TIFF file format. The following restrictions apply:
rd
— TIFF file format will conform to the TIFF Revision 6.0 (June 3 1992) [TIFF] Baseline specification.
— TIFF file format will utilize the extensions described in [TIFF_TN2] to facilitate the inclusion of grey scale
images with baseline JPEG compression in the TIFF
— TIFF file will not contain any other data other than that which is required to describe the image itself.
— Refer to Clause 6 for a complete specification of the TIFF file format.
5.2.3.7 Channel Concept
The architecture of the interface is based upon the concept of virtual channels presented in Figure 7.
Figure 7 — Virtual channels concept
An interface between the Image Controller and an Enrichment Device consists of the following concepts:
— Connection:
There is only one connection between an IC and an ED. The connection is requested by the IC and
enables the ED to allow or deny the connection. ED may need to register its features in a repository
known by IC. The connection defines infrastructure information such as the version of the interface and
all the capabilities of the ED. The connection applies to the logical connectivity of the devices. There is no
restriction about the physical connectivity.
— Channel:
One connection may have many channels. A channel is a logical connection between an Image
Controller and an Enrichment Device. A channel defines the processing type; each channel has its own
flow control. A channel is associated to a unique bi-directional message and processing request queue.
More than one channel can be opened at the same time between an Image Controller and a physical
Enrichment Device.
— Session:
Sessions define a time periods, which are primarily used to control statistical information. Therefore it is
not within the scope of this version of the Mailpiece Processing interface. The interface allows more than
one simultaneous session to be active on a single channel. Since a session is a statistics reporting
device, it may be defined on attributes other than time, for instance originating machine, or mail center.
Figure 8 and Figure 9 depict two typical uses of the channel concept, for an OCR system:
Figure 8 — Channel concept use cases
Figure 9 — Channel concept use cases
5.2.3.8 Client/server model
As far as possible the interface shall adhere to a strict client/server model, where the IC is the client and the
ED the server:
— all exchanges are initiated by the IC;
— there is one and only one reply for each request;
— the only exception are the exchanges required by the Flow Control mechanism (see 5.3.1.7, UC102 –
Control Flow).
5.2.3.9 Server Selection Service
When the ED System is switched on and ready to be used by an IC, it publishes its presence to a Server
Selection service. Depending on the middleware chosen the Server Selection service might be a UDDI
service, Connection service, or simply a file. The Server Selection service will also provide a way to check for
version compatibility. The IC will use the Server Selection service to discover the ED and retrieve the data
necessary to establish a communication.
NOTE The ED acts as a service and therefore publishes its presence to the IC(s).
5.2.3.10 Connection Sequence
The diagram on Figure 10 shows the agreed (CEN Suppliers Workshop 03/12/2003 – 05/12/2003 Barcelona)
connection model between an Enrichment Device and the Image Controller.
NOTE The sequence diagrams contained within these sections are for explanation purposes only and reflect the
common understanding which was gained by the CEN Suppliers group during the development of the specification. The
SDD in 7 specifies the behaviour of the interface in detail using sequence diagrams.
Figure 10 — ED- IC connection model
The Enrichment Device published its presence and the services it provides in a Server Selection service,
when it starts running.
Insofar, the ED is the initiator of the connection.
The Image Controller tries to establish a connection to the ED through using the Server Selection service to
discover the desired service. The ED can accept or deny the connection request.
After a connection has been established, the IC requests the capabilities of the ED; the ED returns its
capabilities.
The capabilities should describe the full functionality of the ED, not considering temporary conditions derived
for example by the status of the Video coding pool.
5.2.3.11 Flow Control Model
The flow control between an Enrichment Device and the Image Controller can be based on one of two
possible models, request or semaphore model. The model-of-choice selected in the suppliers workshop (CEN
Suppliers Workshop 03/12/2003 – 05/12/2003 Barcelona) is the semaphore model; this decision is logically
linked to the decision of declaring the IC as the client and the ED as the server, as this simplifies the
transactions between ED and IC and helps sticking to a “pure” client/server model.
The major shortcoming of this model is the possible “overflow” of the ED, while the IC has not processed the
flow control request; this is critical in case of on-line video coding and has been solved by setting a limit in the
number of pending transactions.
The Image Controller opens the required channel (depending upon the mailpieces which require processing).
The Enrichment Device allows or denies the open channel request. Mailpiece processing may now start.
The sequence diagram presented on Figure 11 shows how the IC can open the channel for the capability C1,
and how the flow control (PutChannelStatus) can be used by the ED over this channel to request mailpieces.
Figure 11 — Open a channel for certain capabilities
The diagram presented on Figure 12 shows how the ED regulates the flow of mail pieces submitted by the IC
Figure 12 — Mail pieces flow regulation
In the semaphore model, the Image Controller submits mailpieces to the Enrichment Device until the
Enrichment Device signals that the Image Controller should stop.
The Enrichment Device maintains an internal queue which has upper and lower threshold limits. When these
are reached, the Image Controller is instructed to stop or start submitting mailpieces respectively.
Results may be transmitted out of sequence.
The Enrichment Device may dispatch the images internally for parallel processing, but the enrichment
operations (OCR or video coding) will not necessarily complete in order. Since the IC has to keep track of
outstanding requests anyway, it should be able to handle out-of-order result transmissions.
In case of many ICs connected to the same ED, the ED shall guarantee one queue for each IC. If there is a
maximum number of IC connections (or Channels) acceptable for an ED, and if this maximum number of
channels has been reached, the next Channel request should be refused by the ED. The ED has the
responsibility to manage load balancing between the different channels.
After closing of a channel, neither the IC nor the ED has to keep track of any outstanding transaction. The ED
shall delete the relevant images.
5.3 Specific Requirements
5.3.1 Use-Case Reports
5.3.1.1 UC001 - Publish Presence
5.3.1.1.1 Brief Description
When an Enrichment Device is switched on and ready to be used by an IC, it publishes its presence in a
Server Selection service which the IC can use to discover Enrichment Devices which are available.
5.3.1.1.2 Actors
Customer.
5.3.1.1.3 Flow of Events
5.3.1.1.3.1 Basic Flow
The basic flow covers the scenario where no exception handling is required. The Server Selection service for
publication is available and can be reached by the ED, and there is no existing entry for this ED.
1) The customer switches on the Enrichment Device
2) The Enrichment Device starts and prepares itself to handle connection requests from the Image
Controller.
3) When the Enrichment Device is ready to handle connection requests, it publishes its presence in the
Server Selection service which is used by the IC to discover available Enrichment Devices.
Figure 13 — State diagram ED
The state diagram (Figure 13) shows that the ED is only published when it is ready to accept a connection
request.
If it is not ready to handle a connection request, it is not published.
5.3.1.1.3.2 AF001-01: Enrichment Device cannot register
If the Enrichment Device cannot register into the Server Selection service, it will attempt to register again after
a delay defined by the supplementary requirement Publish_Retry_Delay. Until the registration is successful
the Enrichment Device will remain unavailable for the Image Controller.
5.3.1.1.3.3 AF001-02: Server Selection Service contains an entry for the Enrichment Device
This alternative flow is middleware dependent.
5.3.1.1.3.4 AF001-03: Server Selection Service Restarted
This alternative flow is middleware dependent.
When the Server Selection service is restarted, the references are not guaranteed to be available. There is no
requirement that the Server Selection service is persistent. Therefore the Enrichment Device shall ensure that
its current reference is entered correctly in the Server Selection service at all times. See SR 001-03.
5.3.1.1.4 Special Requirements
SR ID Description
SR 001-01 If the Enrichment Device cannot register with the Server Selection Service, it will re-attempt
after a time defined by the supplementary requirement Publish_Retry_Delay. Registration
attempts can be repeated indefinitely.
SR 001-02 An Enrichment device shall remove its entry in the Server Selection service when it is
stopped intentionally. In crash situations this behaviour is not mandatory.
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...