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Executable Calling Signature for ICE 2006 1 June 2006 

executable parameter_file image_directory target_sigset query_sigset similarity_file 

quality_target_sigset quality_query_sigset

Executable Arguments 

Table A describes the arguments used above in the calling signatures for the executables. It is 

important to note that all filenames will be relative to the working directory from which the 

program is instantiated. 

Parameter name Type Format Description 

parameter_file Input XML An XML document that specifies experiment 

description information, configuration 

parameters and the name of metadata files. 

image_directory Input string The relative path to the image (data) directory 

target_sigset Input Sigset The name of the target signature set. This 

document will contain a list of the target 

images. 

query_sigset Input Sigset The name of the target signature set. This 

document will contain a list of the query 

images. 

similarity_file Input/ 

Output 

Similarity 

Matrix 

The name of the similarity file. For the 1:1 and 

1:many matching experiments, this will be the 

primary output data structure. This will be an 

input data structure for the similarity 

normalization experiment. 

quality_target_sigset Output 

(optional) 

Sigset The name of the target sigset to which quality 

scores should be written. This file should be a 

copy of the input target sigset with quality 

scores added. Ignore this parameter if your 

executable does not compute quality scores. 

quality_query_sigset Output 

(optional) 

Sigset The name of the query sigset to which quality 

scores should be written. This file should be a 

copy of the input query sigset with quality 

scores added. Ignore this parameter if your 

executable does not compute quality scores. 

Table A Description of executable arguments 

Directory Structure 

Each participant will be given the directory structure shown in Figure A. All experiments (and 

thus executables) will be instantiated from the top level (/algorithm_name) directory. 
Executables must be installed to the /bin directory. Any libraries needed by executables should 

be installed in the /lib directory. After installation, both the /bin and /lib directory will be made 

read and execute only. All required outputs (similarity matrices, signature sets, etc) generated 

during experiment execution should be written to the /output directory. Users will be given write 

permission to the /output directory. The /temp directory should be used for any temporary files 

generated during program execution. Users will be given read and write privileges to the /temp 

directory. It is important to note that files output to the temporary directory may be deleted prior 

to subsequent runs of experiments. Images will be stored outside of the directory structure in 

Table A. Users will be given the relative path to the images via the image_directory parameter. 

Figure A ICE 2006 directory structure.

/bin /lib /temp /output 

/algorithm_name 

Important Notes 

• The name of the /algorithm_name directory will correspond to the name of your 

submitted executables which must adhere to the ICE 2006 algorithm naming convention. 

• Algorithms will be instantiated (run) from the /algorithm_name directory. 

• Executables should reside in the /bin directory. 

• Do not hard code any drive information. Specifically, do not assume that the 

/algorithm_name directory will be on the C: drive. 

• The output directory will be directly below the /algorithm_name directory. Do not create 

a /output/output or /bin/output directory. 

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• Any modifications to the $path or the $ld_library_path variables should be done by your 

install script and should be temporary (i.e. should only effect the current command or 

terminal console). 

Image Directory 

The image directory is a string that specifies the relative path to images. This string should be 

appended to each of the data files listed in the Signature Sets. For examples, if the parameter 

image_directory is ‘..\images\’ and the Sigset refers to a image named ‘tic\image1.tiff’, you 

should process the image in the file ‘..\images\tic\image1.tiff’. Note: the value of the 

image_directory argument will be consistent with the underlying operating system. Thus, 

‘..\images\’ and ‘../images/’ would be provided for windows and Linux operating system 

respectively. 

Parameter Files 

Overview 

Parameter files are XML documents that provide experiment description information and 

configuration values for executables. To simplify their processing, configuration values will 

always be specified via the values of attributes in the parameter file. 

Structure 

While the precise content of the Parameter files has not been determined, the structure will be 

similar to the example shown below in 

Figure B. In this example, elements are depicted blue (capitalized), attributes are red (lowercase) 

and attribute values are black (uppercase and in quotes). The Experiment element is the outer 

element. It has three attributes named name, type and feature_extraction_mode respectively. For 

the ICE experiments the type attribute will have a value of “1-1” and the value of the 

feature_extraction_mode attribute will be “Full”. The Experiment element has three child 

elements Target, Query and LogFile. Both the Target and Query elements will have one 

attribute: capture_device. The value “LG2200” will refer to images similar to those captured at 

the University of Notre Dame. Attribute values and information describing other capture devices 

may be distributed at a later time. The LogFile element specifies where your algorithm should 

write status and debug information. 
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<?xml version="1.0"?> 

<Experiment name= type= feature_extraction_mode="Full" > 

capture_device="LG22

capture_device="LG22

name="1

"1_to_1" "1-1"

 <Target 00" /> 

 <Query 00" /> 

 <LogFile _to_1_logfile.txt" /> 

</Experiment>

Figure B Example of a parameter file 

Attribute Type Allowed 

Values 

Comments 

name (Experiment) String The text of this string provides a 

name for the experiment. This 

attribute is not needed by users. 

type String 1-1 The type of task and executable that 

this is experiment is being 

evaluating. 

feature_extraction_mode enumerated Full The enumerated values of this 

attribute specify whether ground 

truth data is provided to aid in 

feature extraction. For ICE 2006 

the value will be “Full” which 

indicates that ground truth data is 

not provided. 

capture_device enumerated LG2200 

TBD 

The enumerated values of this 

attribute specify the type of sensor 

used for image capture. 

Name (LogFile) string Filename All logging information generated 

by the program should be written to 

this file in the output directory. 

Table B Description of elements in the similarity header.

Parsing 

Due to their simple structure, Parameter files are readily parsed with any XML or XPath parser. 

Source implementation of C++ and Java classes for parsing Parameter files are provided in the 

BEE (Biometric Experimentation Environment) distribution. These classes, which use the XPath 

parser, are available to ICE 2006 participants. Parsers will not be made available for other 

languages (e.g. Matlab). However, users should be able to easily create parsers in other 

languages using the C++ classes as a guide. 
Writing 

ICE users will not be required to write (output) parameter files. 

Signature Sets (Sigsets) 

Overview 

Signature Sets (Sigsets) are the primary input structure for ICE 2006. They will use used to list 

the files in the Target and/or Query sets. 

Structure 

The Signature Set document will provide a list of images. XML will be used because its 

hierarchical structure facilitates a flexible representation of the relationships between subjects, 

sessions, sensors and files. Specifically, the Signature Set will consist of a list of Signature

(subjects) element. Each Signature element will contain one or two Presentation child elements 

that correspond to the iris image(s). 

Figure C illustrates the simple Signature Set structure with elements depicted blue, attributes 

depicted red (lowercase) and attribute values depicted black (uppercase and in quotes). This 

example has four biometric-signature elements that represent three subjects. (There are two 

presentations for subject “557”.) The signatures are named “557”, “558” and “559”. Each 

signature has one presentation (image) of a left iris. All images are tiff files. 

<?xml version="1.0" encoding="UTF-8"?> 

<biometric-signature-set xmlns="http://www.bee-biometrics.org/schemas/sigset/0.1" 

 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 

 xsi:schemaLocation="http://www.bee-biometrics.org/schemas/sigset/0.1 

 http://www.bee-biometrics.org/schemas/sigset/0.1/general.xsd"> 

<biometric-signature name="557"> 

 <presentation name="242311" modality="IRIS-LEFT" file-name="lg2200/242311.tif" file-format="tiff"/> 

 </biometric-signature> 

 <biometric-signature name="557"> 

 <presentation name="242979" modality="IRIS-LEFT" file-name=" lg2200/242979.tif" file-format="tiff"/> 

 </biometric-signature> 

 <biometric-signature name="558"> 

 <presentation name="243902" modality="IRIS-LEFT" file-name=" lg2200/243902.tif" file-format="tiff"/> 

 </biometric-signature> 

 <biometric-signature name="559"> 

 <presentation name="241364" modality="IRIS-LEFT" file-name=" lg2200/241364.tif" file-format="tiff"/> 

 </biometric-signature> 

</biometric-signature-set> 

Figure C Example of a Signature Set with one left iris image per subject. 

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Figure D illustrates the general Signature Set structure with elements depicted blue, attributes 

depicted red (lowercase) and attribute values depicted black (uppercase and in quotes). This 

example has four complex-biometric-signature elements that represent three subjects. (Note: 

While presentation elements grouped under a single complex-biometric-signature are 

guaranteed to correspond to the same subject, separate signatures may correspond to the same 

subject.) The signatures are named “557”, “558” and “559”. Signature “557” has two 

presentation (capture sessions) labeled “242311” and “242979” respectively. Each signature 

consists of left iris image and a right iris images which are specified with the modality attribute 

in the presentation element. All images are stored as tiff images. 

<?xml version="1.0" encoding="UTF-8"?> 

<biometric-signature-set xmlns="http://www.bee-biometrics.org/schemas/sigset/0.1" 

 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 

 xsi:schemaLocation="http://www.bee-biometrics.org/schemas/sigset/0.1 

http://www.bee-biometrics.org/schemas/sigset/0.1/general.xsd"> 

<complex-biometric-signature name="557"> 

 <presentation name="242311" modality="IRIS-LEFT" file-name=" lg2200/242311.tif" file-format="tiff"/> 

 <presentation name="242321" modality="IRIS-RIGHT" file-name=" lg2200/242321.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

 <complex-biometric-signature name="557"> 

 <presentation name="242979" modality="IRIS-LEFT" file-name=" lg2200/242979.tif" file-format="tiff"/> 

 <presentation name="242334" modality="IRIS-RIGHT" file-name=" lg2200/242334.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

 <complex-biometric-signature name="558"> 

 <presentation name="243902" modality="IRIS-LEFT" file-name=" lg2200/243902.tif" file-format="tiff"/> 

 <presentation name="242421" modality="IRIS-RIGHT" file-name=" lg2200/242421.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

 <complex-biometric-signature name="559"> 

 <presentation name="241364" modality="IRIS-LEFT" file-name=" lg2200/241364.tif" file-format="tiff"/> 

 <presentation name="a42319" modality="IRIS-RIGHT" file-name=" lg2200/a42319.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

</biometric-signature-set> 

Figure D Example of a Signature Set with two iris images per subject.

Parsing 

Signature sets are difficult to parse due to their rich hierarchical structure. Fortunately, C++ and 

Java classes for parsing Similarity Matrices are provided in the BEE (Biometric Experimentation 

Environment) distribution. These classes are available to ICE 2006 participants. We also provide 

examples or the use of these parsers. It is important to note that some of the BEE examples 

assume the simplified Sigset structure in which each Signature has precisely one Presentation, 

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each Presentation has precisely one Component and each Component has precisely one Data 

member. Care should be used which using this simplified version of the Similarity structure. 

Parsers are not provided for other languages (e.g. Matlab). However, users should be able to 

create a Java wrapper that parses the Signature Set and passed the appropriate data structures to 

this executables. 

Writing 

Like most XML documents, Signature sets are easier to write than they are to parse. Thus, users 

can either use the C++ and Java classes supplied in BEE to create Signature Sets or output them 

directly. We recommend that the supplied classes be used because they have been rigorously 

tested and can easily be made compliant with changes in the schema for Signature Sets. 

Signature Sets (Sigsets) with Quality Scores 

Overview 

All Signature Sets (Sigsets) has an optional element at the signature level that is used to specify a 

quality score for the signature. The value of the score will be a positive integer where larger 

values correspond to better images. This will be the output format created by executables. 

Structure 

The structure of Signature Sets with quality scores with identical to the standard Signature Set 

format with the exception of the added quality score. The quality score is an attribute of the 

biometric-signature and complex-biometric-signature elements. It is important to note that 

quality scores correspond to signatures. Thus, in the case of complex-biometric-signature 

elements the score should be representative of both presentations in the signature. Figure E and 

Figure F depict example output Signature Sets with quality for the input Signature Sets depicted 

previously in Figure C and Figure D. 
Figure E Example of a Signature Set with one left iris image per subject. 

<?xml version="1.0" encoding="UTF-8"?> 

<biometric-signature-set xmlns="http://www.bee-biometrics.org/schemas/sigset/0.1" 

 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 

 xsi:schemaLocation="http://www.bee-biometrics.org/schemas/sigset/0.1 

 http://www.bee-biometrics.org/schemas/sigset/0.1/general.xsd"> 

<biometric-signature name="557" quality=”98” > 

 <presentation name="242311" modality="IRIS-LEFT" file-name="lg2200/242311.tif" file-format="tiff"/> 

 </biometric-signature> 

 <biometric-signature name="557" quality=”90” > 

 <presentation name="242979" modality="IRIS-LEFT" file-name=" lg2200/242979.tif" file-format="tiff"/> 

 </biometric-signature> 

 <biometric-signature name="558" quality=”100” > 

 <presentation name="243902" modality="IRIS-LEFT" file-name=" lg2200/243902.tif" file-format="tiff"/> 

 </biometric-signature> 

 <biometric-signature name="559" quality=”80” > 

 <presentation name="241364" modality="IRIS-LEFT" file-name=" lg2200/241364.tif" file-format="tiff"/> 

 </biometric-signature> 

</biometric-signature-set> 

<?xml version="1.0" encoding="UTF-8"?> 

<biometric-signature-set xmlns="http://www.bee-biometrics.org/schemas/sigset/0.1" 

 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 

 xsi:schemaLocation="http://www.bee-biometrics.org/schemas/sigset/0.1 

http://www.bee-biometrics.org/schemas/sigset/0.1/general.xsd"> 

<complex-biometric-signature name="557" quality=”72” > 

 <presentation name="242311" modality="IRIS-LEFT" file-name=" lg2200/242311.tif" file-format="tiff"/> 

 <presentation name="242311" modality="IRIS-RIGHT" file-name=" lg2200/242311.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

 <complex-biometric-signature name="557" quality=”88” > 

 <presentation name="242979" modality="IRIS-LEFT" file-name=" lg2200/242979.tif" file-format="tiff"/> 

 <presentation name="242311" modality="IRIS-RIGHT" file-name=" lg2200/242311.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

 <complex-biometric-signature name="558" quality=”94” > 

 <presentation name="243902" modality="IRIS-LEFT" file-name=" lg2200/243902.tif" file-format="tiff"/> 

 <presentation name="242311" modality="IRIS-RIGHT" file-name=" lg2200/242311.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

 <complex-biometric-signature name="559" quality=”98” > 

 <presentation name="241364" modality="IRIS-LEFT" file-name=" lg2200/241364.tif" file-format="tiff"/> 

 <presentation name="242311" modality="IRIS-RIGHT" file-name=" lg2200/242311.tif" file-format="tiff"/> 

 </ complex-biometric-signature> 

</biometric-signature-set> 

Figure F Example of a Signature Set with two iris images per subject.

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Parsing 

While the standard tools for parsing Signature Sets can be used to parse Signature Sets with 

quality, the ICE 2006 protocol does not require users to parse Signature Sets with quality. 

Writing 

Like most XML documents, Signature Sets with quality are easier to write than they are to parse. 

Thus, users can either use the C++ and Java classes supplied in BEE to create Signature Sets or 

output them directly. We recommend that the supplied classes be used because they have been 

rigorously tested and can easily be made compliant with changes in the schema for Signature 

Sets. 

Similarity Matrices 

Overview 

Similarity Matrices are the primary output structures of recognition algorithms in ICE 2006. 

They consist of a header that specified the type and dimension of the contained data and the 

N×M scores from the biometric algorithm. 

Structure 

The Similarity Matrix is similar to many image files in that it contains a textual header 

prepended to a binary representation of a N×M data structure. The structure of the header is 

depicted below in Figure G. Here, we see that the header consist of four lines. The first line must 

contain the either the character ‘D’ (for distance matrix) or the character ‘S’ (similarity matrix) 

followed by the character ‘2’. The second and third lines should contain the name of the target 

and query signature set respectively. The target and query name should be the same as they were 

specified in the call to the matching executable. The fourth line should contain the characters 

‘MF’, a space, the number of signatures in the query sigset, a space, the number of signatures in 

the target sigset, a space and the integer 0x12345678 written in binary format. All four lines in 

the header should be terminated by an end-of-line character. Table C describes the elements in 

the similarity header. 
Figure G Example of the Similarity Matrix header.

D2 

BEE_DIST/signature_sets/ICE_Exp_1.0.1_Target.xml 

BEE_DIST/signature_sets/ICE_Exp_1.0.1_Query.xml 

MF 1425 1425 xV4 

Name Format Separator Comments 

Storage Type Character ‘S’ or ‘D’ none Specified similarity scores, ‘S’, or 

distance measures ‘D’. 

Version The character ‘2’ eol The value ‘2’ corresponds to the 

version of similarity matrix. 

Target name string eol This string should be the same as the 

name of the target sigset provided to the 

matching algorithm. 

Query name string eol This string should be the same as the 

name of the query sigset provided to the 

matching algorithm. 

Format The characters ‘MF’ space The values correspond to a matrix, ‘M’, 

containing float, ‘F’, values. 

Rows integer space The number of signatures in the query 

set. 

Cols integer space The number of signatures in the target 

set. 

Magic number 0x12345678 

(4-bytes binary) 

eol This binary value is used to check for 

Endian (byte swapping). 

Table C Description of elements in the similarity header.

The scores are written to the file immediately following the header. These should be N×M 4-byte 

binary floating point values. Here, N is the number of signatures in the query set and M is the 

number of signatures in the target set. Thus, the first M values correspond to comparing the first 

query image to each of the target images. There must not be any white space characters 

separating scores in the body of the Similarity Matrix. 

Important Notes 

• The dimensions of the similarity matrix corresponds to the number of signature elements 

in the target and query sigsets not the number of presentations. 

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Parsing 

C++ and Java classes for parsing Similarity Matrices are provided in the BEE (Biometric 

Experimentation Environment) distribution. These classes will are available to ICE 2006 

participants. Parsers will not be made available for other languages (e.g. Matlab). However, users 

should be able to easily create parsers in other language using the C++ classes as guides. 

Writing 

C++ and Java classes for writing Similarity Matrices are provided in the BEE (Biometric 

Experimentation Environment) distribution. These classes are available to ICE 2006 participants. 

Parsers will not be made available for other languages (e.g. Matlab). However, users should be 

able to easily write Similarity Matrices in other language using the C++ classes as guides. 

Log Files 

Each executable should produce a log file. The name (and directory) for the log file will be 

provided in the parameter file via the name attribute of the LogFile element. The log file should 

provide sufficient information so that we (with your limited support) can easily and quickly 

troubleshoot your algorithm. Since we will have limited time to troubleshoot programs, please 

provide detailed debug messages in your log file. 
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Example of Calling Signature for ICE 

executable_name /home/ice/parameters/parameter_exp1.xml /home/ice/images/ 

/home/ice/sigsets/target_exp1.xml /home/ice/sigsets/query_exp1.xml 

output/similarity_exp1.mtx xml output/quality_target_exp1.xml 

output/quality_query_exp1.xml 

Clearly, this entire command would be on one line. Notice that both absolute and relative 

directories can be used.