Convolutional Neural Networks Used to Date Photographs

Nowadays, the information provided by digital photographs is very complete and very relevant in different professional fields, such as scientific or forensic photography. Taking this into account, it is possible to determine the date when they were taken, as well as the type of device that they were taken with, and thus be able to locate the photograph in a specific context. This is not the case with analog photographs, which lack any information regarding the date they were taken. Extracting this information is a complicated task, so classifying each photograph according to the date it was taken is a laborious task for a human expert. Artificial intelligence techniques make it possible to determine the characteristics and classify the images automatically. Within the field of artificial intelligence, convolutional neural networks are one of the most widely used methods today. This article describes the application of convolutional neural networks to automatically classify photographs according to the year they were taken. To do this, only the photograph is used, without any additional information. The proposed method divides each photograph into several segments that are presented to the network so that it can estimate a year for each segment. Once all the segments of a photograph have been processed, a general year for the photograph is calculated from the values generated by the network for each of its segments. In this study, images taken between 1960 and 1999 were analyzed and classified using different architectures of a convolutional neural network. The computational results obtained indicate that 44% of the images were classified with an error of less than 5 years, 20.25% with a marginal error between 5 and 10 years, and 35.75% with a higher marginal error of more than 10 years. Due to the complexity of the problem, the results obtained are considered good since 64.25% of the photographs were classified with an error of less than 10 years. Another important result of the study carried out is that it was found that the color is a very important characteristic when classifying photographs by date. The results obtained show that the approach given in this study is an important starting point for this type of task and that it allows placing a photograph in a specific temporal context, thus facilitating the work of experts dedicated to scientific and forensic photography.

INNOVATIONS IN FORENSIC PHOTOGRAPHY: LOOKING TO THE FUTURE

The article analyses the current state of methods and means of forensic capturing and research photography. Based on the latest achievements of science and technology, the authors of the article formulated promising directions for the development of photographic means and methods in solving the problems of solving and investigating crimes.

Forensic science and fractal nature analysis

Forensic photography, also referred to as crime scene photography, is an activity that records the initial appearance of the crime scene and physical evidence in order to provide a permanent record for the court. Nowadays, we cannot imagine a crime scene investigation without photographic evidence. Crime or accident scene photographs can often be reanalyzed in cold cases or when the images need to be enlarged to show critical details. Fractals are rough or fragmented geometric shapes that can be subdivided into parts, each of which is a reduced copy of the whole. Fractal dimension (FD) is an important fractal geometry feature. There are many applications of fractals in various forensic fields, including image processing, image analysis, texture segmentation, shape classification, and identifying the image features such as roughness and smoothness of an image. Fractal analysis is applicable in forensic archeology and paleontology, as well. The damaged image can be reviewed, analyzed, and reconstructed by fractal nature analysis.

Looking through the lens of a sexual assault examiner: novel trends and approaches in forensic photography

Background Sexual violence is cancerous, and it malignantly affects all strata of our community regardless of age, gender, race, ability, and social status. Excellent healthcare service requires professionals who can do a sexual assault examination, collect medico-legal evidence, take photographs of patients' anatomy that was involved in the assault and document what is there and where it is in relation to the victims or perpetrators body or other parts of the crime scene, whether or not it is connected to the crime. Main text The objective of this article to orient the professions to the novel trends and approaches in forensic photography, namely e-consent, digital cameras and their accessories, dedicated forensic software, and photographic protocols and procedures. Conclusion The inadequate and improper collection, preservation and presentation of evidence can lead to crime scene errors and fewer conviction rates. Training in forensic photography is vital and a game-changer in the sexual assault examination.

Comparison of superficial wound documentation using 2D forensic photography, 3D photogrammetry, Botscan© and VR with real-life examination

Evidence acquisition, interpretation and preservation are essential parts of forensic case work that make a standardized documentation process fundamental. The most commonly used method for the documentation and interpretation of superficial wounds is a combination of two modalities: two-dimensional (2D) photography for evidence preservation and real-life examination for wound analysis. As technologies continue to develop, 2D photography is being enhanced with three-dimensional (3D) documentation technology. In our study, we compared the real-life examination of superficial wounds using four different technical documentation and visualization methods.To test the different methods, a mannequin was equipped with several injury stickers, and then the different methods were applied. A total of 42 artificial injury stickers were documented in regard to orientation, form, color, size, wound borders, wound corners and suspected mechanism of injury for the injury mechanism. As the gold standard, superficial wounds were visually examined by two board-certified forensic pathologists directly on the mannequin. These results were compared to an examination using standard 2D forensic photography; 2D photography using the multicamera system Botscan©, which included predefined viewing positions all around the body; and 3D photogrammetric reconstruction based on images visualized both on screen and in a virtual reality (VR) using a head-mounted display (HMD).The results of the gold standard examination showed that the two forensic pathologists had an inter-reader agreement ranging from 69% for the orientation and 11% for the size of the wounds. A substantial portion of the direct visual documentation showed only a partial overlap, especially for the items of size and color, thereby prohibiting the statistical comparison of these two items. A forest plot analysis of the remaining six items showed no significant difference between the methods. We found that among the forensic pathologists, there was high variability regarding the vocabulary used for the description of wound morphology, which complicated the exact comparison of the two documentations of the same wound.There were no significant differences for any of the four methods compared to the gold standard, thereby challenging the role of real-life examination and 2D photography as the most reliable documentation approaches. Further studies with real injuries are necessary to support our evaluation that technical examination methods involving multicamera systems and 3D visualization for whole-body examination might be a valid alternative in future forensic documentation.

Avaliação da técnica fotográfica nas autópsias forenses do Instituto Médico Legal de Porto Velho – RO, no Brasil

Photography in forensic autopsies of violent death is intended to document the material evidence of the offense and guide decisions in the courts of law. In this paper, we tested the hypothesis that the current photographs, presented in the forensic reports of the Dr. José Adelino da Silva Legal Medical Institute, in Porto Velho, located in the capital of the State of Rondônia, in Brazil, would be inappropriate for not meeting the criteria that must contribute to the final quality of forensic photography. Through a retrospective analysis, we evaluated the quality of the photographs incorporated in the reports of the forensic autopsies related to violent death. We concluded that more than half of the incorporated photographs (52.6%) were not technically feasible and, regarding this criterion, they should not have been used in the reports. Considering the limitations found, it is suggested strategies to be adopted at the Institute to correct them, being essential the elaboration of a protocol with the harmonized procedures for the photographic record of the forensic autopsies with a view to improving the forensic expert reports.