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RAYGRAF Project financed by the Ministry of Science and Higher Education in Poland from funds on science in years 2009 – 2011 as development project Software producer and distributor: Research and Training Centre of Polish Forensic Association Programme Guide The Polish ForensicAssociation University of Warsaw Authors of software: Andrzej Łuszczuk M.Sc. Krystyn Łuszczuk M.Sc. Eng. Scientific consultation: Prof. Tadeusz Tomaszewski Dr Mieczysław Goc English version: Agnieszka Łukomska (M.A.)

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System and equipment requirements: TO ENSURE PROPER RUNNING OF PROGRAMME THE FOLLOWING REQUIREMENTS SHOULD BE MET: 2. IMPORTANT: required monitor (display) resolution 1024 × 600 or higher. In lower resolution, the programme cannot be started. In lower resolution, the programme cannot be started. 3. Recommended default font size "9" at 96 dpi (not more than 120 dpi). 4. In Windows „.NET Framework" platform in v or more recent version should be installed. It is necessary for proper running of the programe. should be installed. It is necessary for proper running of the programe. 1.Operating system: Windows XP, Windows Vista, Windows 7 or Windows 8.

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Applied graphometrical examination methods and definitions have been elaborated by authors of programme

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Definitions Total width of specimen Total width of specimen - distance between extreme points of first and last graphical element of examined specimen. Graphical element of specimen - fragment of specimen, which has been drawn with one impulse, having its beginning and end; can be separated from but also constitutes the specimen: Graphical element of specimen - fragment of specimen, which has been drawn with one impulse, having its beginning and end; can be separated from but also constitutes the specimen: letter, morpheme, syllable, digraph, word. Width of graphical element - distance between extreme points of graphical which constitutes a graphical element. Spacing between graphical elements of specimen - distance between graphical sets of specimen, resulting from motoric habit of writer. Spacing between graphical elements of specimen - distance between graphical sets of specimen, resulting from motoric habit of writer. Width of spacing between graphical elements of specimen - distance between extreme points of consecutive elements, i.e. between ending point of preceding element and starting point Width of spacing between graphical elements of specimen - distance between extreme points of consecutive elements, i.e. between ending point of preceding element and starting point of the following element. Base segment - line which links the points of the same location in both specimens, and constituting the base for matching of those points (horizontally and in relation to size). Base segment - line which links the points of the same location in both specimens, and constituting the base for matching of those points (horizontally and in relation to size). Leng th (height) of graphical element - segment which links the highest and lowest points of graphical element, designated by parallel lines framing a given graphical element. Leng th (height) of graphical element - segment which links the highest and lowest points of graphical element, designated by parallel lines framing a given graphical element. Slope of graphical element - angle between the core of axis of symmetry of graphical element and base segment, after it has been leveled. Slope of graphical element - angle between the core of axis of symmetry of graphical element and base segment, after it has been leveled.

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RAYGRAF programme enables the verification of text similarity with application of the following methods: Analysis of leng th s and slope angles Handwriting density analysis Impulse density analysis

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Base segment. The length of this segment in both specimens serves to carry out their horizontal and size-related „match” L1 L2 L3L4L5 L6 α2α2 α6α6 OPTION I - Analysis of lenghts and slope angles Angles have been marked for demonstration purposes (for better legibility) only for two elements, i.e. L2 and L6. The programme calculates them for all designated elements. Angles have been marked for demonstration purposes (for better legibility) only for two elements, i.e. L2 and L6. The programme calculates them for all designated elements.

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y y x x P2 Ending point α α L L Axis Y Axis X Angles are always measured in radians "to the left" from X axis (counterclockwise). P1(x,y) Ending point P1(x,y) α α L L To remind: remind: 360 ⁰ = 2 * πrad = 2 * 3,14 = 6,28 rad 1 rad ≈ 57,325⁰ 1⁰ ≈ 0,017 rad OPTION I Starting point Beginning of coordinate system is always in starting point of graphical element. Lenght of graphic element Slope of graphic element Calculation the lenghts and slope angles Examined graphic element

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Specimen B Specimen A OPTION I - Analysis of lengths and slope angles – VERY IMPORTANT αβ 1. THE SAME NUMBER OF GRAPHICAL ELEMENTS MUST BE DESIGNTED IN BOTH SPECIMEN. 2. STARTING AND ENDING POINTS OF ANALOGICAL GRAPHICAL ELEMENTS IN EXAMINED SPECIMENS MUST HAVE IDENTICAL POSITION. SPECIMENS MUST HAVE IDENTICAL POSITION. Below you find the example of failure to observe this rule. Below you find the example of failure to observe this rule. Change of point sequence is FORBIDDEN. It will cause discrepancy in angles value of nearly π radians (180 ⁰) and can entail a significant error in specimen analysis. Change of point sequence is FORBIDDEN. It will cause discrepancy in angles value of nearly π radians (180 ⁰) and can entail a significant error in specimen analysis. Starting point Ending point Starting point Ending point The leng th s of sections (red marked) are identical but their slope angles differ dramatically.

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OPTION I - Analysis of lengths and slope angles (cont.). Results of measurements OPTION I - Analysis of lengths and slope angles (cont.). Results of measurements As results, sequences of measurements of lengths of graphical elements and slope angles are obtained for both specimens: Sequence of lengths of elements in specimen „A” : La1, La2, La3 ………. Lan Sequence of slope angles in specimen „A”: α1, α2, α3 ……… αn Sequence of lengths of elements in specimen „B” : Lb1, Lb2, Lb3 ………. Lbn Sequence of slope angles in specimen „B”: β1, β2, β3 ……… βn Then, the differences in lengths and angles of corresponding elements of specimens are determined: Differences in lengths: ΔL1= | La1- Lb1| ΔL2= | La2- Lb2| ΔL2= | La2- Lb2| ΔL3= | La3- Lb3| ΔL3= | La3- Lb3| …...………….. …...………….. ΔLn= | Lan- Lbn| ΔLn= | Lan- Lbn| Differences in lengths: ΔL1= | La1- Lb1| ΔL2= | La2- Lb2| ΔL2= | La2- Lb2| ΔL3= | La3- Lb3| ΔL3= | La3- Lb3| …...………….. …...………….. ΔLn= | Lan- Lbn| ΔLn= | Lan- Lbn| Differences in angles: ΔK1=| α1 – β1 | ΔK2=| α2 – β2 | ΔK2=| α2 – β2 | ΔK3=| α3 – β3 | ΔK3=| α3 – β3 | …...………….. …...………….. ΔKn=| α3 – β3 | ΔKn=| α3 – β3 | Differences in angles: ΔK1=| α1 – β1 | ΔK2=| α2 – β2 | ΔK2=| α2 – β2 | ΔK3=| α3 – β3 | ΔK3=| α3 – β3 | …...………….. …...………….. ΔKn=| α3 – β3 | ΔKn=| α3 – β3 |

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Red colour indicates differences between elements of specimens A and B < 10%. These elements were considered as matching. Green colour indicates differences between elements of specimens A and B (tu odpowiedni znak) 10%. These elements were considered as non matching. Total number of examined graphical elements Nog = 6 Number of matching lengths Lzg = 3 Linear coefficient Wpl = 100* Lzg/Nog [%] Wpl = 100*3/6 = 50% Linear coefficient Wpl = 100* Lzg/Nog [%] Wpl = 100*3/6 = 50% Number of matching angles Kzg = 4 Angular coefficient Wpk = 100*Kzg/Nog [%] Wpk = 100*4/6 = 66,7% Angular coefficient Wpk = 100*Kzg/Nog [%] Wpk = 100*4/6 = 66,7% Differences in lenghts[%] ΔL1ΔL2ΔL3ΔL4ΔL5ΔL6 Differences in angles [%] ΔK1ΔK2ΔK3ΔK4ΔK5ΔK6 OPTION I - Analysis lenghts and slope angles (cont.). Graphic show of results (example). Graphic show of results (example). OPTION I - Analysis lenghts and slope angles (cont.). Graphic show of results (example). Graphic show of results (example).

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S2S2 S1S1 S3S3S4S4S5S5S6S6S7S7 Number of graphical elements N morf =7 Number of letters in specimen N liter =9 Scp - Total width of specimen OPTION II – Handwriting density analysis

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OPTION II - Handwriting density analysis (cont.) After designating of beginnings and ends of graphical elements, we calculate the following : After designating of beginnings and ends of graphical elements, we calculate the following : Sum of widths of graphical elements Sm = ΣS Morpheme density coefficient Wgm = Scp/(Sm*Nmorf) After calculations for both specimens, we determine the following: Similarity of morpheme density coefficients: 100% * Wgm (lower) / Wgm (higher) Similarity of morpheme density coefficients: 100% * Wgm (lower) / Wgm (higher) Similarity of letter density coefficients: 100% * Wgl (lower) / Wgl (higher) Similarity of letter density coefficients: 100% * Wgl (lower) / Wgl (higher) Basing on found similarities of density coefficients, similarity between specimens is verified Letter density coefficient Wgl = Wgm/Nliter

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O1O1 O2O2O3O3O4O4O5O5O6O6 Number of spaces between graphical elements N odst = 6 Scp - Total width of specimen OPTION III – Impulse density analysis

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OPTION III – Impulse density analysis (cont.) After designating of beginnings and ends of spaces between graphical elements, we calculate the following : Sum of width of spacing So = ΣO Impulse density coefficient Wimp = Scp/(So*Nodst) After calculations for both specimens, we determine the following : Similarity of impulse density coefficients : 100% * Wimp (lower) / Wimp (higher) Similarity of impulse density coefficients : 100% * Wimp (lower) / Wimp (higher) Basing on determined similarities of impulse coefficients, similarity between specimens is verified

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RAYGRAF RAYGRAF RAYGRAF enables the evaluation of similarity of handwriting specimens basing on 5 parameters: 1.Similarity of linear coefficients Wpl 2.Similarity of angular coefficients Wpk 3.Similarity of morpheme density coefficients Wgm 4.Similarity of letter density coefficients Wgl 5.Similarity of impulse density coefficients Wimp The level of measuring accuracy is determined by expert within an acceptable percentage range to account for the differences between specimens being compared (5%; 10%;15% i 20%). RAYGRAF enables the evaluation of similarity of handwriting specimens basing on 5 parameters: 1.Similarity of linear coefficients Wpl 2.Similarity of angular coefficients Wpk 3.Similarity of morpheme density coefficients Wgm 4.Similarity of letter density coefficients Wgl 5.Similarity of impulse density coefficients Wimp The level of measuring accuracy is determined by expert within an acceptable percentage range to account for the differences between specimens being compared (5%; 10%;15% i 20%).

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Lengt h s of graphical elements marked by expert Slope angles of graphical elements marked by expert. OPTION I – Analysis of lengths and slope angles (example) Results of linear and angular similarity

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OPTION II – Handwriting density analysis (example) Similarity coefficients Wgm i Wgl

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OPTION III – Impulse density analysis (example) Similarity coefficients Wimp

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Basic principles of verification of handwriting specimens in RAYGRAF RAYGRAF is a measuring tool, which examines geometrical shape of specimens. It does not account for other features (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. PROGRAMME IS A MEASURING TOOL AND DOES NOT INTEND TO SUBSTITUTE THE EXPERT A final decision on match of examined entries belongs to the user !!! RAYGRAF is a measuring tool, which examines geometrical shape of specimens. It does not account for other features (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. (such as tremor, points of stoppage, shading distribution) which may appear in examined specimens and be in conflict with high geometrical similarity. PROGRAMME IS A MEASURING TOOL AND DOES NOT INTEND TO SUBSTITUTE THE EXPERT A final decision on match of examined entries belongs to the user !!!

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You are welcome to use our programme

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