Abstract

This application involves a crime scene footprint photography and extraction method and extraction device that can photograph a first image of the footprint in the oblique light from a fixed angle, and a second image of the footprint in the diffuse reflected light from a fixed angle; divide the first image's brightness component V1 by the second image's brightness component V2 to produce their brightness distribution ratio V3; and extract a third image corresponding to the brightness distribution ratio V3. According to the technical scheme of this application, the technology has a better image collection effect, and can provide better image materials for future footprint acquisition and identification, and can also remove the patterns of the footprint trace carrier, and leave only footprint images displayed clearly and cognizably. Moreover, the method is simple and the results are more accurate.

IPC Classes  ?

• G06K 9/00 - Methods or arrangements for reading or recognising printed or written characters or for recognising patterns, e.g. fingerprints
• G06T 5/00 - Image enhancement or restoration
• G06T 5/50 - Image enhancement or restoration using two or more images, e.g. averaging or subtraction
• G06K 9/46 - Extraction of features or characteristics of the image
• G06K 9/20 - Image acquisition
• A61B 5/1174 - Identification of persons based on the shapes or appearances of their bodies or parts thereof using footprinting

Abstract

The present application relates to an extraction method and extraction device for crime scene footprint patterns through photographing. The method comprises: under the irradiation of glancing light, photographing at a certain angle to acquire a first image of a footprint; under the irradiation of diffuse reflection light, photographing at a certain angle to acquire a second image of the footprint; conducing a division operation on a brightness component V1 of the first image and a brightness component V2 of the second image to obtain a brightness distribution ratio V3 of the two; and extracting a third image corresponding to the brightness distribution ratio V3. According to the technical solution of the present application, the image collection effect is made better, thereby providing a better image material for the subsequent footprint acquisition and confirmation, so that patterns of an object bearing marks of the footprint can be removed with clear and distinguishable footprint patterns left only; and moreover, the algorithm is simple, and the result is more accurate as well.

IPC Classes  ?

• G06T 7/00 - Image analysis

Goods & Services

Scanners [data processing equipment]; electronic agendas; weighing apparatus and instruments; electro-dynamic apparatus for the remote control of signals; precision measuring apparatus; electric installations for the remote control of industrial operations; optical apparatus and instruments; electric monitoring apparatus; alarms; galvanic cells.

Abstract

A pressure-sensing light and shadow imaging system comprises a bearing medium (1), a sensing surface (2), an optical source (3), a light pool (5), and an imaging surface (6). The bearing medium (1) is disposed on a top end of the pressure-sensing light and shadow imaging system, a lower surface of the bearing medium (1) contacts the sensing surface (2), a lower surface of the sensing surface (2) is closely joined with an upper surface of the light pool (5), and the imaging surface (6) is disposed below the light pool (5). Texture substances (7) contact the bearing medium (1) to form a pressure image. The image can reflect distribution of contact pressure, and can reflect pressure distribution and pressed order of the substances. A method for processing a footprint image formed by the pressure-sensing light and shadow imaging system processes multiple single-frame footprint images into a complete footprint image comprising all footprint characteristics, so as to remove background noises.

IPC Classes  ?

• A43D 1/02 - Foot-measuring devices
• G06K 9/58 - Image preprocessing, i.e. processing the image information without deciding about the identity of the image using optical means
• A61B 5/117 - Identification of persons