Any digital video experts here?

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Arran90
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If there are any digital video experts here then I would appreciate it enormously if you could analyse the following video and answer as many of my questions as possible.

https://youtu.be/Gn3Vj5BjteY

This video originated as analogue CCTV footage recorded onto a VHS video tape. I have been semi-reliably informed that the CCTV installation utilised a Tecton Miniplex multiplexer, which takes several video feeds and overlays the camera number and time stamp, then outputs a video signal to a recording device. The maximum number of camera inputs on a Miniplex is 17.

The analogue video recording was converted to a digital video file by the Metropolitan Police in 2005 or 2006 then released to the public in 2008 via their website. It is not longer available there. I believe that the video was originally offered to the public to download as a .wmv file but it has since been converted in order to upload to YouTube.

1. What was the most likely method used to digitise the analogue video recording? It is notable that the active area is surrounded by a black border and on the left hand and right hand outer edges are two grey columns. A friend verbally informed me that such a border indicates that it was probably digitised by pointing a digital video camera at an analogue monitor whilst the VHS tape was being played back. Is he correct?

2. The original analogue video recording almost certainly had a 4:3 aspect ratio but the aspect ratio in the digital video file is not 4:3 and the width of the active area is squashed. How did the digital video file most likely end up with an incorrect aspect ratio? Is there an easy method to restore a 4:3 aspect ratio to the active area – unless it has been cropped?

3. What is the original frame rate of the video and the original number of horizontal lines?

4. The CCTV footage has a vertical serial number 3 10 41071. This is clearest in the car park scenes at 4:00 minutes. It appears to be subsequently added in the digital domain as the CCTV footage exhibits a certain degree of juddering with the camera number and the time date captions moving along with the rest of the image, but the position of the serial number remain fixed. I will award a virtual gold medal to anybody who can answer this question: What is the true purpose of this serial number?

Note: The quality of the video is not good as it has originated from a (possibly worn out) VHS tape then further degraded by lossy video compression, but the blurring out of large areas of the background on scenes apart from the car park is intentional.
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Procrastonator
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(Original post by Arran90)
If there are any digital video experts here then I would appreciate it enormously if you could analyse the following video and answer as many of my questions as possible.

https://youtu.be/Gn3Vj5BjteY] https://youtu.be/Gn3Vj5BjteY[/url]

This video originated as analogue CCTV footage recorded onto a VHS video tape. I have been semi-reliably informed that the CCTV installation utilised a Tecton Miniplex multiplexer, which takes several video feeds and overlays the camera number and time stamp, then outputs a video signal to a recording device. The maximum number of camera inputs on a Miniplex is 17.

The analogue video recording was converted to a digital video file by the Metropolitan Police in 2005 or 2006 then released to the public in 2008 via their website. It is not longer available there. I believe that the video was originally offered to the public to download as a .wmv file but it has since been converted in order to upload to YouTube.

1. What was the most likely method used to digitise the analogue video recording? It is notable that the active area is surrounded by a black border and on the left hand and right hand outer edges are two grey columns. A friend verbally informed me that such a border indicates that it was probably digitised by pointing a digital video camera at an analogue monitor whilst the VHS tape was being played back. Is he correct?

2. The original analogue video recording almost certainly had a 4:3 aspect ratio but the aspect ratio in the digital video file is not 4:3 and the width of the active area is squashed. How did the digital video file most likely end up with an incorrect aspect ratio? Is there an easy method to restore a 4:3 aspect ratio to the active area – unless it has been cropped?

3. What is the original frame rate of the video and the original number of horizontal lines?

4. The CCTV footage has a vertical serial number 3 10 41071. This is clearest in the car park scenes at 4:00 minutes. It appears to be subsequently added in the digital domain as the CCTV footage exhibits a certain degree of juddering with the camera number and the time date captions moving along with the rest of the image, but the position of the serial number remain fixed. I will award a virtual gold medal to anybody who can answer this question: What is the true purpose of this serial number?

Note: The quality of the video is not good as it has originated from a (possibly worn out) VHS tape then further degraded by lossy video compression, but the blurring out of large areas of the background on scenes apart from the car park is intentional.
I’m 16 and this lockdown I took an interest in watching me and my brothers childhood vhs tapes. I heard they start degrading after ten years and me and my brother are 16 and 12. We used a senevo vsr and an old tv it started off good with my brothers earliest tape till we got to the 3 rd tape 2009 and it stopped working at 1 hour 16 minutes when it should go on for 5 hours more . The other older tapes worked fine they had a few lines which was expected. The fourth tape in the beginning crashes aswell. If his tapes are 11 years old kept in good condition and use quality camera records and tape recorders what went wrong? Mine are older and they have people that have passed away in them and other important memories.I doubt they would work. Do I need to clean the vhs head? I really want to convert them but with alevels and ukcat I don’t have the time. My mom said she kept the camcorders with the videos on them. This message went on for long but I hope someone comes up with a non bias solution as online websites always scare you into converting them to dvd so they can make profit. So I want a fair opinion from someone with knowledge. Please help these videos contain some important people and memories.
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