CCTV systems have evolved in recent years

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1 Fujifilm s Digital CCTV and Security Guide 1. What digital media should I use? 2. How much footage can I store on the media I use? 3. How do I calculate how much data can fit onto my media? 4. How do I deal with using digital images as evidence? 5. Do I need to meet the Data Protection Act requirements? 6. How do I ensure I am compliant with the Data Protection Act? 7. The Fujifilm Digital Evidence Kit- The solution in the bag. 1. What digital media should I use? CCTV systems have evolved in recent years with digital technology establishing itself as an emerging part of future surveillance solutions. With digital technology, the very way in which it stores data allows a wider variety of recording media to be employed, so which one should be used? The real deciding factor is not so much what you want to do with the recordings but how much footage you need to store and what you intend to do with any footage which may need to be transferred to another party. Based predominantly around hard drive integral storage, digital solutions will usually store their data in a buffer. This data, including video, audio and other information, will then either be overwritten when the hard disk is filled, or removed to another storage media and securely archived. Digital archiving is constantly increasing in capacity, predominantly due to archiving media being used and supported by the IT industry. The most basic digital archiving media is the Compact Disc. The CD has become well known and widely used over the years, and is useful for storing data capacities of up to 700MB. CDs come in two variants, the CD-R which is a WORM type media, (Write Once, Read Many) and the CD-RW which can be rewritten. Where capacities in excess of 700MB are common, users and installers are likely to make use of the constantly developing DVD capacities. DVD capacities currently dwarf those achievable with CDs, and future developments will see these figures rise dramatically. Indeed, the next proposed generation of DVDs will far exceed the current capacities! There are other digital storage formats including various digital tapes, which offer fault-free operation and high speed data transfers, and data storage technology such as 4mm, DLT, and LTO Ultrium data tapes, offering higher storage capacities and faster data transfer speeds. 2. How much footage can I store on the media I use? W hilst it is fairly straightforward how much footage can be stored on analogue media, digital media is more complex. Digital image sizes are governed by how much data they are made up of. One image captured off a specific camera could vary in size when compared to another according to a number of criteria. There are no hard and fast rules when it comes to file sizes and here we will explain why size, whilst being important, is unlikely to be constant! Digital image file sizes can vary according to the information contained. This differs from analogue where a VHS cassette will store 25 frames per second for the entire 180 minutes it is recording. It matters not if the video is of a busy street, an empty car park or a white wall.

2 The image quality can be pin-sharp or so low that it is unusable, but you still will record 25 frames per second for 180 minutes in real-time mode. Digital images however are databased in that each pixel in the image contains colour information. It might initially seem that as all images captured by a system are the same resolution, they will be the same size, but they are not. This is because image compression algorithms will convert the data in order to eliminate as much redundant information as possible. Where there are large areas of continual tone, some image compression algorithms will calculate the number and positions of the pixels and store that data rather than from each individual pixel. Others will take an average value from a group of pixels, and will rebuild the image using grouped averages. Subsequently, an image of an empty car park with a white wall on one side might take up little space, because image compression can use a small amount of data to create certain areas of the image. However when the same car park is filled with cars of different shapes and colours, and with a certain amount of activity, the size of each image, in relation to the data it contains will rise significantly, and less footage can be archived in any given memory. Environmental factors can also affect image file sizes. For example, a frame of video showing an external scene on a clear sunny day will be smaller than the same scene on a rainy day. This is simply because the rain will be constantly changing, and will break up any continuous areas of tone, with the result that compression will be less effective. The size of files is affected by the quality of the video (lower resolutions use bigger pixels, equating to less data), the image compression algorithm and ratio used, the image contents, noise in the picture and environmental conditions. So how much data can you fit on digital media such as a CD? There is no definitive answer. Despite some manufacturers quoting how many hours will fit on a drive, there are too many variables to provide an accurate answer. We understand this is not very useful for users and installers alike trying to decide which media to use. By understanding image file sizes from some market-leading DVR recorders and considering how much footage specific media are able to contain, we hope to give you a greater understanding. Issues affecting file sizes and how much footage you can store Busy scenes take up more space Colourful scenes take up more space A lot of movement such as rain or other activity takes up more space Redundant or repeated data take up less space as they can be compressed A low resolution and a low compression ratio can make an image much smaller 3. How do I calculate how much data can fit on my media? B efore we look at image file sizes, we need to understand how files are measured. This information is necessary to carry out any accurate calculations. Digital files are made up of bytes of information. Where bytes are being specified the abbreviation is B. Where you see a b being used it is referring to bits, often used when measuring data transfer speeds. A byte is one piece of data, and inevitably will be too small to be of any interest with relation to calculations of video sizes. Most image file sizes will be quoted in kilobytes (KB) which is equal to 1000 bytes. A megabyte (MB) is 1000 kilobytes, or 1,000,000 bytes, and a gigabyte (GB) is 1000 MB. It will not be long before DVRs appear offering terabytes (TB) of storage, a TB being 1000 GB. The common factor here is that the multiple is 1000* *The above numbers are shown in decimal (Base 10). In Binary (Base 2), one kilobyte (1KB) is equal to 1,024 bytes and that number should also be used when performing binary calculations.

3 Currently most archiving of footage for generalpurpose CCTV solutions will be CD-Rs. There are two main reasons for this. Firstly the drives and media costs are low. Secondly, there is a requirement for evidential video to be written to WORM (Write Once, Read Many) media. Therefore it is worth considering how much video can be archived onto CD. Remember that evidential footage will need to be accompanied by replay software, plus other documentation, so this will use up some capacity! Calculating how much footage a CD-R (or any digital media) can contain is a simple task. You need to know: The capacity of the media The average image file size of the recorded footage The frame rate at which it is recorded. Fujifilm CD-Rs have a current capacity of 700MB. To make things simpler, convert this figure to KB, as the image file sizes are quoted as such. Therefore 700MB is equivalent to 700,000 KB. To calculate this figure, simply multiply the size in MB by To calculate from GB, multiply the size in GB by 1000 to achieve MB then again by 1000 to achieve the figure in kilobytes (KB). The following example shows how we calculated a 700MB CD-R would contain just over 1 hour 4 minutes of footage. In this example, with image quality equivalent to S-VHS performance, average image file sizes are 18KB. For the purposes of this explanation it can be assumed that the recording rate is 10 pictures per second (PPS). Divide the capacity in KB by the average image size, and this will give the number of images that can be supported. In this case a CD will hold 38,888 pictures. If this figure is divided by 10 (the record rate of 10pps), it gives the number of seconds that can be stored. Simply divide by 60 again to get the number of minutes that can be stored. JPEG COMPRESSION, 10pps, STANDARD RESOLUTION 700MB x 1000 = 700,000KB 18KB (file size) = 38,888 (images) 10 (pps) 60 (seconds) =64.8 minutes. However taking an average of 40KB as the file size, perhaps a recording in the highest resolution mode, and recording in real-time (25 pictures per second) a CD would contain only 11.6 minutes. JPEG COMPRESSION, 25pps, HIGH RESOLUTION 700MB x 1000 = 700,000KB 40KB (file size) = 175,00 (images) 25 (pps) 60 (seconds) = 11.6 minutes The following calculation can be used to ascertain how much footage can be stored on any media: Media Capacity in MB x 1000 (or Media Capacity in GB x 1000 x 1000) File Size in KB = image capacity PPS rate 60 (to calculate minutes 60 again to calculate hours) It is vital that installers and users understand the potential of archiving media when specifying a solution. It is also useful to note there is an element of specmanship, with some providers quoting figures for the lowest possible resolutions at very slow frame rates. However most users and installers prefer standard or high resolution images and should calculate accordingly. 4. I have chosen the media I wish to use, now how do I deal with using digital images as evidence? W hen it comes to the criteria of using video images as evidence, the requirements can appear to be something of a minefield. Add the use of digital images to the equation, and question marks start to appear with regularity. Quite often, depending upon whom you are talking to, you will hear a different version of the so-called digital dilemma when it comes to using CCTV footage for evidential purposes.

4 However the police and courts are aware of the potential offered by digital surveillance solutions, and do not want to curtail the use of a credible and efficient tool in the fight against crime. The Police and Scientific Development Branch have published guidelines for the use of digital images as evidence. The guidelines do not specify which compression algorithm or archiving media should be used instead taking the view that final quality and a credible audit trail are more important. An audit trial for digital CCTV is very much the same as one for an analogue system. However, with digital systems the audit trail must also keep records of which copy is designated as a Master Copy and which is a Working Copy. Here we outline the steps to ensuring your evidence is admissible: STEP 1 Obtain the relevant authority to capture images CCTV systems must obtain, where necessary, the relevant authority to capture images. They should be regularly maintained and an audit trail commenced at the earliest opportunity. STEP 2: Create a Master Copy Because digital images can be replicated without degradation, and due to the fact that the first storage medium is usually an integral part of the DVR, a Master Copy needs to be created. It needs to be stored securely and kept in accordance with evidential procedures. It should be taken directly from the original recording medium and stored onto a removable medium. This removable medium must be a WORM type device. WORM (Write Once, Read Many) devices such as CD-R, DVD-R and DVD+R media add a level of credibility to digital images as once the Master Copy is written the data cannot be affected and changes cannot be made. STEP 3 Create a Working Copy A Working Copy, again on WORM media, can be produced simultaneously with the Master Copy or subsequent to the Master Copy from the original footage, or can be produced directly from the Master Copy. STEP 4 Make sure your Master and Working copies are clearly labelled and include; The relevant image sequences A text file stating any hardware or software requirements for replay Metadata such as time and date information bound to the footage License-free software to view and make copies of the footage, including editable sequences Instructions on how to copy the footage to VHS cassette plus details of any changes that may occur if the cassette is then played alongside the digital footage. You may also include (though this is not a requirement) a copy of the audit trail, a test sequence to ensure replay is correct, and authentication or verification software*. *The DVR manufacturer should supply this. 5. Now I know how to deal with digital evidence, do I also need to ensure that I comply with the Data Protection Act? T he Data Protection Act came into force on 1 March While this legislation has in no way prevented the use of CCTV in a security context, it has placed certain restrictions on its use and the way in which the evidence gathered by this method is handled. Not all CCTV systems are covered by the Data Protection Act. Whether your system is covered by the Data Protection Act depends upon how the system is used.

5 By way of an example, small retailers would not be covered by the Act if their store contained a couple of cameras which could not be remotely controlled to allow individuals to be tracked around the premises, and if the only data stored were the images picked up by the cameras. Furthermore, the footage should only be used for evidential purposes, to be passed to the police if investigating an incident in the shop. If additional data such as Point of Sale information including operator details, method of payment etc. were included, the Act may well apply. If a retailer uses the system to view members of staff to appraise their level of work, the situation changes. In such a case the individual worker becomes the focus of the information gathering, and the video footage gives the management significant information about that individual. In such a case the system will be covered by the Act. There are three main considerations when assessing whether a system will need to be compliant with the Data Protection Act. However, if the cameras are used to generally offer security in the environment and subsequently catch a crime in progress, this is not for the user s own business purposes- although stopping theft is obviously in their own interest! When CCTV systems are more complex, the chances of a system being covered by the Act increase, as such systems will usually have the ability to focus on individuals or examine, in detail, scenes, which identify individuals by behavioural activity. However, where general surveillance is captured by such systems, that footage will not be covered by the Act. If a system is not covered by the Data Protection Act, it is sill vital that correct evidential procedures are followed to ensure captured footage is admissible. Should the system be covered by the Act, system owners are required to formally notify the Office of the Information Commissioner that they are processing data. Are the cameras operated remotely to pan, tilt or zoom in and out to track or look at specific individuals? Are the CCTV images ever used to observe someone s behaviour for the user s own business purposes, such as assessing the performance of staff members? Are CCTV images ever passed to a third party other than a law enforcement agency such as the police? If the answer to all three of these points is NO then the system may not fall within the scope of the Data Protection Act. When considering the second point, you must be careful to fully understand what is meant by the users own business purposes. For example, if a retailer uses a system to watch staff behaviour to assess whether they are doing a good job, it is for their own business purposes. 6. What are the Data Protection Act rules? T he processing of that data must comply with the eight fundamental and enforceable principles of good practice, which state that data must be: Fairly and lawfully processed Processed for limited purposes Adequate, relevant and not excessive Accurate Not kept longer than necessary Processed in accordance with the data subject s rights Secure and confidential Not transferred to countries without adequate protection.

6 So how do these principles relate to the way in which CCTV systems are used day-to-day and what should operators do.. Well, the first step is that those operating a CCTV system that falls under the Act must provide a clearly-stated document of the objectives for using it and a statement of the responsibilities of those involved in operating and managing the system. Those who are being filmed must also be made aware that they are entering an area where CCTV is active. This warning is usually achieved by signage, which should also include details of the purpose of the scheme, the operators and their contact details. If correct signage is not in place, then the scheme will be considered covert. Covert recording may only take place if: informing people that recording is taking place will compromise your objectives; you have reasonable cause to suspect specific criminal activity and the covert processing is only carried out for a limited and reasonable period of time. Under the Data Protection Act, individuals who have been recorded can request a copy of any recording that has been made of them. Access may only be denied where such an action would compromise the detection or prevention of crime, or where it may impede the apprehension or prosecution of offenders. If the operator cannot comply with such a request without disclosing identifiable images of third parties, they must determine whether the images of these parties are held under a duty of confidence, in which case the images should be edited to disguise these identities. Privacy is also a major issue to consider. Cameras should only be set to view images that were intended for the objectives of the scheme. If this is not possible without viewing domestic or other areas, which would reasonably be considered private, the owners of these areas must be consulted. If there are any doubts in this respect, it would be prudent to obscure the view such cameras have of private areas. Confidentiality is also a major issue as far as the DPA is concerned, indeed it is one of the most important, having far-reaching effects on areas such as traceability, security and accountability. All images recorded are considered confidential and, to ensure this confidentiality, the Act requires that it should be possible to trace any recorded image to a specific date, time, recording device, recording medium and individual. Copies of evidential images are only admissible provided that there is a clear audit trail to the original. On removing the medium for use in legal proceedings, the operator should ensure that they have documented: The date on which the images were removed from the general system for use in legal proceedings The reason why they were removed from the system Any crime incident number to which the images may be relevant The location of the images e.g. If they were handed to a police officer, the name and station of that police officer; The signature of the collecting police officer The DPA requires that information not be kept any longer than necessary. When using digital based systems, the DVR can often be set to record over images after a certain period of time. The fact that the Act insists on the confidentiality of recorded images means that the recording equipment and the images themselves must be kept secure. One of the best ways of ensuring this is by using secure cabinets. Should the images on the recording medium be retained for evidential purposes, they should be kept in a place in which access is controlled. As far as possible, it should not be possible to interfere with the recording equipment and access should be restricted to maintenance staff and operators.

7 Also crucial to the use of data as evidence is the quality of the CCTV images themselves. To ensure that this is the case, initial checks should take place to ensure the equipment performs properly and the media produces good quality images. Cameras should be properly maintained and serviced. Also, if the system records features such as date, time or location, this information needs to be accurate. 7. The Fujifilm Digital Evidence Kit The solution in the bag T here is a lot to consider with regards to using digital evidence and complying with the Data Protection Act but help is at hand, via Fujifilm s Digital Evidence Kit. The Digital Evidence Kit was designed to bring total peace of mind to users of CCTV and Security recording devices by helping them with their responsibilities in correctly auditing all recordings, and presenting digital material in a form that is admissible as evidence in a court of law. The Digital Evidence Kit contains everything you need to present digital evidence to the authorities. The number of CD Master Copies and Working Copies or DVD format options included depends on requirements but the Standard Kit contains: 50 Fujifilm CD-Rs (two spindles) 25 standard jewel cases 25 slimline jewel cases The Fujifilm Digital Evidence Kit comes in a two-disc CD set allowing for creation of a Master Copy and a Working Copy; and a three-disc Kit that allows the creation of two Working Copies alongside an original Master Copy. A further set is available for those requiring DVD-R or DVD+R media. Fujifilm media has been designed for a longarchival life, ensuring that your evidence stands the test of time. The 25 standard jewel cases and 25 slimline jewel cases have been developed so that the user can decide which type of cases to standardise upon, passing the other - containing a Working Copy - to the relevant authorities. Where a three-spindle kit is used, the cases are supplemented with 25 plastic sleeves. The benefit of slimline cases is that the space required for CD storage is dramatically reduced. Probably the two most important additions are the Digital Evidence Logbook, and the CPS approved Evidence Bags. Fujifilm s CPS approved Evidence Bags feature an easy to use closure seal that provides tamper-evident security against all known methods of attack. Once sealed, any attempts to open the bag will result in the word STOP appearing in white on the orange background. Whilst this clearly identifies tamper attempts, independent testing showed users could not start opening the sealed bag without making it obvious that an attempt had been made. Once evidence is placed in the bag, any attempts to remove it are going to be detected! Logbook to keep audit trails in check with uniquely numbered sheets CPS-approved Tamper Evident evidence bags Procedural Guide CD friendly marker pen (for labelling)

8 Each bag is marked with a unique number, ensuring traceability and enabling accurate pinpointing of breaches in security. Each evidence bag includes a tear-off receipt at the bottom, which has the unique number of the bag printed onto it and sufficient space to allow for the recipient s details to be recorded. The bag is over-printed with a log of all activity from when a CD-R is sealed in until such a time as a copy is called for evidence. A permanent marker pen is included so CDs can be marked with a unique number from the evidence logbook. This is important as labels can affect the balance of CDs during writing and reading, adversely affecting performance and reliability. Following research which highlighted the fact that many users are unaware of how to present digital footage as evidence, a leaflet has been enclosed explaining the basic requirements of how to present digital CCTV footage as evidence along with a handy guide to CCTV. The Evidence Bags allow CDs to be tracked and audited throughout the entire storage and handling process ensuring the admissibility of the footage in court. Each kit contains 25 Evidence Bags providing an audit trail (and proof no tampering has occurred) for each Master Copy. As mentioned earlier, the Data Protection Act requires that it be possible to trace any recorded images to a specific date, time, recording device, recording medium and operator. The Digital Evidence Logbook was developed to enable users to comply with this requirement by creating an audit trail, with its pages designed to fit inside a standard CD case, which are easily detachable for when copies of footage are made. The complete audit trail in a box, the kit makes life a whole lot easier for installers and users alike offering all the tools necessary to ensure that every stage of the evidence gathering process is accurately performed in the eyes of the Law. A copy of each Logbook sheet can be inserted in the case. One with the Master Copy, one with the Working Copy and one retained in the book for management purposes. Each logbook sheet is colour-coded and designed to ensure that a record of the CD-Rdetails; audit information and the evidence bag number are all logged. The evidence log sheets each contain a unique number, which removes the need for users to manage their own numbering systems.