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fredg1583 · Forensic Video Newbie

I just obtained a new Field System this past week and now I am trying to decide how best to deploy it. I understand the basics but I am left with so many questions. What should I be trying to obtain in the form of evidence? What overall goal is realistic? My city currently has no standard set for the implementation of CCTV so I am currently at the mercy of the "victim: when it come to the quality of the video evidence. There seem to be so many options and I want to ensure that I am getting the best possible evidence to start with. Any thoughts or suggestions will be greatly appreciated.

samburgiss · Forensic Video Expert

Q1. What should I be trying to obtain in the form of evidence?

The goal is to collect original evidence from the DVR, create an uncompressed working copy of that video for clarification and then create high-quality interoperable results for circulation.

With that said your first goal is to collect the original evidence.

Your goal is to collect original evidence onto a CD or DVD. Some require the use of a transport media such as a flash drive, USB flash drive or hard drive. These media are used to move the collected video onto CD or DVD.

The two types of file formats collected from DVRs are proprietary and standard. Proprietary files require player software from the manufacturer of the DVR to play. Standard files have common file extensions such as AVI or MPG and can be played using commonly available video players such as Windows Media Player - assuming you have the proper CODEC installed.

The DVR usually dictates which format file you will collect but in some cases may give you a choice.

Q2. What overall goal is realistic?

If you can view the video on a screen you should be able to collect it as evidence. Once you collect it you can create a working copy and clarify it then circulate results that others can view on their computers.

Q3. There seem to be so many options and I want to ensure that I am getting the best possible evidence to start with.

True, there are many options. The DVR will dictate exactly how many options you have available for collection. For example, one DVR may have many types of output but another may have only composite video connections.

One key thing to keep in mind when going to the field is to always verify and examine the video after you collect it. There are several reasons for this:
* You may end up with no evidence at all, for example, the CD or DVD may not burn properly (this is very common).
* You may end up with low quality evidence, for example, some forms of file input recompress the video (this is very common) and you end up with lower quality video than what you see playing on the screen of the DVR. In this case you can collect the video with composite connection.

Using more than one of the many options, in other words, collecting video in more than one format is not a bad thing. The great thing about taking the laptop and all equipment into the field is that you can verify and examine the quality of the video as you do the collection.

fredg1583 · Forensic Video Newbie

I had the chance to use the field kit today. I must admit I tried to make it harder than it really was. I was able to obtain some pretty good video on some known suspects. According to the detective in charge of the case, this is really going to help her close the case. Thanks for this great tool!