Subject: Examination of CCTV Footage of Toll Booth received from Shri Sudesh Kumar.
- (A) Material Received : Two video clips one in .avi format and one in .rec1 format received wide email from Shri Sudesh Kumar on 01 April 2015 , copy of email is attached.
- (B) Query : To analyse the video Clip and give the report as following requirements:
- (1) Colour and make of the bike is to be identified.
- (2) Possible registration number(s) of the bike are to be identified.
- (3) If registration number of the bike can’t be identified then list of confirming letters and digits in the registration number are to be identified.
- (C) Examination: As mentioned above, two files were received for examination, namely “59M & 60M_20141001145500_ 20141001145702_ID_0000.REC1” and “60M_ 20141001145500_ 20141001145702_ID_0000.avi. For this, examination of properties of both files revealed as follows:
- The properties of file “59M & 60M_20141001145500_ 20141001145702_ID_0000.REC1” indicate it is in .rec1 format. It is an encrypted video clip which appears to be a proprietary format for SAMSUNG recording and network systems.
- The second file bears almost the same name “60M_ 20141001145500_ 20141001145702_ID_0000.AVI”, and its format is .avi, i.e. audio-video interleaved.
- This second file is also a video clip that can be read (viewed) in a standard Windows-based media player, like VLC Media Player.
- Using the video conversion tool, Total Video Converter, an attempt was made to ascertain the contents of the first file which is in .rec1 format. A screenshot of the conversion given below indicates that the contents of this file are the same as the second file in .avi format.
- As the second file format, i.e. .avi, is more compatible with Windows-based tools, the examination and analysis was done on this file using various tools and methods as explained below.
- (D) Methodology: The entire video clip, namely “60M_ 20141001145500_20141001145702_ ID_ 0000.AVI” was first run in VLC media player to identify the subject bike and riders. The clip appears to be one at a Toll Tax payment Booth, in a two-wheeler lane, where a number of two wheelers are seen crossing over the payment booth after making payment. The questioned bike and riders are the seventh vehicle to appear in the video clip in this lane. The following screenshot (Screenshot 1) refers…
The film was paused in some of the frames where the bike number appeared clearer than the rest, and screenshots of these frames were taken. The screenshots were then treated in an image-processing software, Adobe Photoshop, to enhance the readability of the figures and characters, as well as better clarity into the color and make of the bike. The screenshots were given a “sharp” filter to sharpen the appearance; despeckled, to remove the specks that appear after sharpening; and the contrast enhanced to increase the difference between the lightest and the darkest colors and shades so that the picture becomes clear. The screenshots were also zoomed at 50% and 200%, respectively, to manipulate the size of the objects to facilitate reading. The following individual frames have also been taken from the video footage, besides Screenshot 1 above, in which the frame number and timing are also indicated in the frame itself…
As these framegrabs are still pictures taken from the original footage provided to us, the original footage has not been tampered in any way. Only the framegrabs have been treated with tools available for sharpening the readability of the objects in the images.
As AVI files are interleaved audio and video fields with separate negative and positive attributes, it is necessary that at least two or more frames are grabbed for analysis – at least one with eve field on, and one with odd field on (as shown by the frame numbers). This becomes necessary as the interleaving often leaves some objects unclear or speckled for a complete analysis.
The framegrabs (screenshots) shown were first applied at two levels of the “Sharp” filter in the Adobe Photoshop application software. As this filter yielded some “speckles” (dots of sharpness), the “Despeckle” filter was applied to remove the speckles. Finally, the contrast tool was applied to enhance the difference between the white pixels and the black pixels in the number plate. The results obtained before and after the application of the tools is given in the following images…
The make of the bike was further compared with the possible make of similar appearance available on the Internet, which was compared with the zoomed pic of frame 14:56:34. We were able to identify the possible model through a close comparison of the two pics. Both are reproduced below, together for the purpose of clarity..
- (E) Analysis and Observations: The analysis of the file has been done in accordance with our findings as detailed above, and the following has been observed seriatim, vis-à-vis the queries posed to us…
- Colour and make of the bike is to be identified: The vehicle is a black Bajaj Avenger bike, to the best of our judgment and analysis.
- Possible registration number(s) of the bike are to be identified: Going by the best possible zooms and sharpness made available by us, the vehicle carries a registration number of DL 3S AV 4213, as shown in the following pic…
- As the “De-speckling” has not entirely removed the speckles created by the “sharpen” filter, it is possible that the last digits of registration number could read 4713, 4715, or 4215 also. However, the possibility of these numbers is remote.
If registration number of the bike can’t be identified then list of confirming letters and digits in the registration number are to be identified: It is confirmed that the letters DL 3S AV 4 and 1 in the registration number plate are confirmed.
Client has also requested over phone, for the clearest possible blown up picture of the pillion rider with some description. The same is provided below…
As can be seen from the pic the person in question is wearing a blue T-Shirt with half-sleeves and having white horizontal stripes.
by MADHUP KUMAR SINGH