1、Designation: E2916 13E2916 18Standard Terminology forDigital and Multimedia Evidence Examination1This standard is issued under the fixed designation E2916; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This is a compilation of terms and corresponding definitions used in the examination of digital and multimedia evidence toinclude the
3、 areas of computer forensics, image analysis, video analysis, forensic audio, and facial identification.1.2 Legal or scientific terms that generally are understood or defined adequately in other readily available sources may not beincluded.1.3 This international standard was developed in accordance
4、with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standard
5、s:2C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction MaterialsE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study to Determine the
6、Precision of a Test MethodE1732 Terminology Relating to Forensic ScienceE2808 Guide for Microspectrophotometry and Color Measurement in Forensic Paint Analysis2.1 ANSI/NIST Standards:2ANSI/NIST-ITL 1-2011 Data Format for the Interchange of Fingerprint, Facial, and Other Biometric InformationNIST SP
7、800-86 Guide to Integrating Forensic Techniques into Incident ResponseNIST SP 800-88 Guidelines for Media Sanitization2.3 ISO Standards:4ISO 9000 Quality ManagementISO/IEC Guide 2:2004 Standardization and Related Activities General VocabularyISO/IEC 19794-5 Information Technology Biometric Data Inte
8、rchange Formats Part 5: Face Image Data2.2 IEEE Standards:3IEEE 100-2000 The Authoritative Dictionary of IEEE Standards Terms, 7th Edition2.5 ASCLD/LAB Publication:6ASCLD/LAB International Supplemental Requirements (Testing), 2011 Edition3. Significance and Use3.1 This terminology includes general a
9、s well as discipline-specific definitions as they apply across the spectrum of imageanalysis, computer forensics, video analysis, forensic audio, and facial identification.4. Terminology: Terms and Definitions4.1 Definitions:achievable resolution, resolving power, nthe measure of imaging systems pra
10、ctical limit to distinguish between separateadjacent elements, typically by imaging a known reference standard.1 This terminology is under the jurisdiction of ASTM Committee E30 on Forensic Sciences and is the direct responsibility of Subcommittee E30.12 on Digital andMultimedia Evidence.Current edi
11、tion approved June 1, 2013Nov. 1, 2018. Published July 2013November 2018. Originally approved in 2013. Last previous edition approved in 2013 as E2916 13. DOI: 10.1520/E2916-13.10.1520/E2916-18.2 Available from National Institute of Standards and Technology (NIST), 100 Bureau Dr., Stop 1070, Gaither
12、sburg, MD 20899-1070, http:/www.nist.gov.3 Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE), 445 Hoes Ln., Piscataway, NJ 08854, http:/www.ieee.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what ch
13、anges have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the off
14、icial document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1acquisition, nin computer forensics, the process of using an access interface to read digital data from a digital source and tocreate a destination object.ad hoc image,nse
15、e uncontrolled image.administrative review, na procedure used to check casework for consistency with agency/laboratory policy and editorialpractice.allocated space, allocated storage, nin computer forensics, the portions of storage that are assigned or reserved for activeinstructions or for data.IEE
16、E 100-2000, (C) 610.10-1994wanthropometric analysis, nin facial identification, an explicit measurement of landmarks on a face and a comparison of thesemeasurements between two samples.anti-forensics, nthe application of a process to modify, conceal or destroy information to inhibit or prevent the e
17、ffectiveness offorensic science examinations.archive, ndata stored for long-term availability and retrieval.archive, vto store data in a manner suitable for long-term availability and retrieval.archive image, nin computer forensics, a bit stream duplicate of data placed on media that is suitable for
18、 long-term storageartifact, na by-product, artificial feature, or change resulting from human activity or a technical process. (Compare noise.)DISCUSSIONExamples include speckles in a scanned picture, “blocking” in compressed images, distortion in over-saturated audio, and the automatic creation oft
19、emporary files due to normal usage of a computer.aspect ratio, nthe ratio of the width to the height of a rectangle, such as an image, a pixel, or an active video frame.attempt, nin facial identification, a submission of a single set of biometric samples to a biometric system for identification orve
20、rification. (Compare biometric search.)audio enhancement, nthe processing and filtering of audio recordings to improve the signal quality and intelligibility of thesignals of interest, such as speech, by attenuating noise or otherwise increasing the signal-to-noise ratio.authentication, n(1) the pro
21、cess of substantiating that the asserted provenance of data is true; (2) the process of substantiatingthat data are accurate representations of what they are purported to be.backlight, nin facial identification, a light source placed behind a subject in a controlled capture that reduces backgroundsh
22、adows.backlit, adja characteristic of a subject or an object that is illuminated from behind.batch mode search, nin facial identification, a mode of searching records in an automated system in which a group of probesare simultaneously or sequentially launched.batch search mode,nsee batch mode search
23、.bias, nthe difference between the expectation of the test results and an accepted reference value.E177, E456, E691, C670binning, nin facial identification, (1) any technique used by a facial recognition (FR) system to organize or optimize searchingbased upon some piece(s) of metadata; (2) the proce
24、ss of parsing (examining) or classifying data to accelerate or improvebiometric matching.biometric match, nin facial identification, determination that two samples correspond to the same source based on some levelof computer-evaluated similarity.DISCUSSIONDoes not inherently imply that the probe and
25、 candidate is the same person.E2916 182biometrics, n(1) a set of measureable anatomical, physiological, or behavioral characteristic that can be used to discriminatemembers of a population; (2) collectively, a set of automated processes used to discriminate members of a population usingmeasureable a
26、natomical, physiological, behavioral characteristics, or combinations thereof.biometric search, nthe submission of a biometric reference as a probe against a biometric system for identification(one-to-many) or verification (one-to-one). (Compare attempt.)bit stream, na continuous stream of bits tran
27、smitted over a channel with no separators between the character groups. IEEE100-2000, (C) 610.7-1995, 610.10-1994wbit stream duplicate, nin computer forensics, an exact, bit-for-bit reproduction of all data objects independent of any physicalmedia upon which that data is stored. (Compare copy.)cache
28、, nin computer forensics, a temporary storage area set aside on a processor, in memory, or in a filesystem to keep frequentlyneeded data readily available, designed to speed up processing and improve performance.candidate list, nin facial identification, a rank ordered list generated from a facial r
29、ecognition search.capture, n(1) the process of recording data such as an image, video sequence, or audio stream; (2) in facial identification, theprocess of collecting a biometric sample from an individual via a sensor.capture, vto record data, such as an image, video sequence, audio stream, or biom
30、etric sample to digital storage, often by meansof a sensor.capture card, frame grabber, na piece of computer hardware that accepts an analog or digital signal and outputs the signal asdigital data.capture device, ndevice used in the recording of data.carve, vin computer forensics, to extract a porti
31、on of data for the purpose of analysis.certification authority, n(1) in computer forensics, a trusted third party entity that issues digital certificates certifying theownership of a public key by the subject named in the certificate, and trusted by both entities engaged in a digital transaction;(2)
32、 in facial identification, a body that issues biometric documents and certifies that the data stored on the documents aregenuine.chain of custody, nthe procedures and documents that account for the possession of a sample by tracking its handling andstorage from its point of collection to its final d
33、isposition. E1732clarification,nsee enhancement.clarify,nsee enhance.class characteristics, nin facial identification and image analysis, characteristics common to many objects or individuals (forexample, the color, make, or model of objects, and for faces, the overall shape of the nose, eyes, or mo
34、uth).clear, vin computer forensics, to overwrite storage space on a medium with non-sensitive data, which may include overwritingnot only the logical storage location of files, but may include all addressable locations. NIST SP 800-88cluster, nin computer forensics, a group of contiguous sectors on
35、storage media, typically the smallest unit of allocation in afilesystem.codec, nan algorithm to encode and decode digital data, typically to reduce the amount of data for transmission or storage.DISCUSSIONA codec is not a storage format, but may be required to interpret stored data.cognitive bias, n
36、(1) a mental error caused by ones simplified information processing strategies; it does not result from anyemotional or intellectual predisposition toward a certain judgment but rather from subconscious mental procedures forprocessing information; (2) a mental error that is consistent and predictabl
37、e; (3) a set of influences that may affect the reliabilityand validity of ones observations and conclusions.cognitive image analysis, nin image and video analysis, a process used to extract visual information from an image by humanevaluation.colorimetry, nthe conversion of instrumental light measure
38、ments into psychophysical descriptions or numerical notations thatcan be correlated with visual evaluations of color and color differences. E2808E2916 183color range,nsee petency test, nan evaluation of a persons knowledge and ability before performing independent work in forensic casework.ASCLD/LAB
39、composite video signal, na single analog video signal that combines a base-band luminance signal with color information bymodulating a subcarrier with chroma signals, typically using one of the National Television System Committee (NTSC), PhaseAlternating Line (PAL), or Sequential Color with Memory
40、(SECAM) pression, na process to reduce the size of a data file or stream while attempting to retain the original semantic meaning ofthat pression ratio, nthe ratio of the size of the data before compression to that of after puter forensics, nthe scientific examination, analysis, or evaluation of dig
41、ital evidence in legal matters.conclusion, na position reached after consideration of a set of facts or examination results.confirmation bias, nthe tendency to search for data or interpret information in a manner that supports ones preconceptions.contextual bias, na deviation in human judgment cause
42、d by factors external to the data that is logically relevant to the decisionat hand.control, nmaterial of established origin that is used to evaluate the performance of a test or comparison. E1732controlled image, nin facial identification, a photographic image captured in accordance with facial ide
43、ntification (FI) or facialrecognition (FR) standards or guidelines (for example, a drivers license photo).copy, vto reproduce information with some level of accuracy.DISCUSSIONDepending on the process used, copying might result in the loss of data. (Compare bit stream duplicate.)CSI effect, npercept
44、ion of the near infallibility of forensic science in response to popular media.data, ninformation in analog or digital form that can be transmitted or processed.data file, na file consisting of stored data (that is, text, numbers, graphics, etc.) as compared to a program file of commands andinstruct
45、ions for a digital device.deblur, vto restore an image by attempting to reverse degradation caused by blur.decryption, na process to return encrypted data to its original unencrypted condition.deinterlace, vto separate an interlaced video frame into its two discrete fields.demonstrative comparison,
46、nin video analysis, a method of presenting similarities or differences, or both among images orobjects, or both without rendering an opinion regarding identification or exclusion.depth of field, nthe distance that is in focus (sharp) when capturing an image based upon the camera and lens, and their
47、settings.digital device, nelectronic equipment which can create, process or store digital data.digital evidence, ninformation of probative value that is stored or transmitted in binary form.digital image, nin image analysis, a photographic image that is represented by discrete numerical values organ
48、ized in atwo-dimensional array.Focal Encyclopedia of Photography4digital object, na collection of logically related information.digital source, na container of digital data that can be acquired by an acquisition tool.digital video recorder, DVR, na stand-alone embedded system or a computer-based sys
49、tem for recording video and, optionally,audio data.digital zoom, na digital camera function that simulates an optical zoom by cropping and enlarging a digital image withoutincreasing the resolution or detail.4 Focal Encyclopedia of Photography, 3rd edition, Richard D. Zakia and Leslie Stroebel, Eds., Focal Press, 1996.E2916 184directory, nin computer forensics, an object or structure used to group files together within a filesystem.directory listing
