Here at TRL Expert Witness & Investigations, our team can analyse almost any type of footage, be it CCTV, dashcam or mobile phone video.
In many investigations, such video material can be of significant value when determining what happened in an incident and why.
Ultimately, getting the best results starts with getting the best evidence. To enable this, we have put together an overview of the dos and don’ts for obtaining and sharing video footage:
DO obtain the original format files.
So that we are working from the best evidence, we would always prefer to work with the original file format – this can be the original or a bit-for-bit copy (as opposed to an edited, compressed or converted version). If the footage you have has been converted to DVD, this likely means that the frame rates, and hence the timings, have been altered. This introduces error to the analysis from the very beginning, meaning any results will be less precise.
DO go back to the source and ask for more.
Tell-tale signs that you don’t have the original file are when the file format ends with .VOB, or there is a ‘title screen’ in the footage, or multiple cameras have been spliced together into a compilation. If these are all that is available, we can still carry out our analyses, but it is always best to go back and ask if the original or raw format is available. This is particularly important for criminal cases, where the Crown Prosecution Service (CPS) will most often provide a compilation disc, and small errors can make a big difference to outcomes.
This also applies to footage that has been obtained from social media. We can always work with something taken from YouTube or similar, if that is all that is available, however it is worth being aware that there are a lot of unknowns with regards to what has changed in the footage when it is uploaded to the internet, or what may have been edited.
DON’T give up! If you have been given a disc of footage and you can’t play it, let us try – we have multiple specialist software programs that we can test it in.
We increasingly find that we are provided with footage that has been obtained by playing a video on a TV screen, and then recording this using a mobile phone. Although this can still be analysed, and often provides useful results if it is all that is available, there is a ‘doubling up’ of the errors created by two sets of recordings with different frame rates.
DO involve us early on. If you are unable to download the raw footage – we may be able to help!
However if you only have one chance to get the footage, and recording a screen is your only option, DO make sure to hold the recording device so that the whole screen is in view. Then hold the recording device as still as possible throughout. DON’T move your camera around or zoom in to show the areas of interest. Our stabilisation techniques work much more effectively when we can see the whole screen throughout the video.
Give us all the information you can
When you send us footage for analysis, DO provide us with all the information you have. Where did you get the footage from? Did you download it yourselves or was a disc sent to you? If you’re giving us a low-quality copy or a screen recording, is this because it’s all that is ever going to be available, or will we be able to get a better copy later?
Making sure we have all this information early on avoids duplication of effort and avoids us basing our analysis on assumptions. In the long run this saves you time and money, as well as getting you the best results.
If in doubt, ask! Contact us with any CCTV or video analysis enquiries, whether traffic collision related, or something else entirely. Along with collision investigation, other cases we have been involved in include thefts, balcony falls, workplace incidents, vehicle route tracing, boat collisions, public safety and security, and high-profile crime investigations. Our Case Management team will be able to talk you through the options and put you in touch with an expert to discuss further.