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Help needed - deliberately shoddy video copying by police


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#1 trachys

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Posted 25 February 2018 - 08:41 PM

In 2012, a surveillance camera captured an incident.  A DVR video file was recorded by a DVD player to a CD-R disc.  Police then "worked" on the file.

 

I have a copy of a report by a forensic video analyst which details the work, but before I share what was done, I would really appreciate hearing from someone more knowledgeable than I (so, anyone) on how the DVR file should have been copied, in order to minimize data loss.

 

All opinions welcome!


Edited by hamluis, 05 March 2018 - 01:00 PM.
Moved from A/V Apps to Gen Chat - Hamluis.


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#2 Platypus

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Posted 25 February 2018 - 09:36 PM

If you simply copy a file, there is no data loss. What's the point of not giving any information to work with?

Top 5 things that never get done:

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#3 trachys

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Posted 25 February 2018 - 11:15 PM

Thanks, Platypus.

 

Okay.

 

1. The DVR file was copied from the disc to the local drive.

2. A DVR player played the file. A screen capture program called Omnivore captured the digital representation as a .MOV file.

3. Camtasia Studio was then used to convert that file to .AVI.

4. Another program was used to create a DVD video disc from the .AVI file.

 

It looks like this was done so that a date/time caption could be added to the video, but the end result is barely legible. I wonder, would a direct copy of the 'original' DVR have substantially better quality?



#4 mightywiz

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Posted 26 February 2018 - 04:42 PM

I don't understand what your trying to do?

 

any video that has been modified from the original format is not usable by the police.   video has to remain in an unedited from the original source to be usable in court.



#5 Chris Cosgrove

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Posted 26 February 2018 - 04:48 PM

I am surprised that the original surveillance imagery did not include time and date, this is a critical aspect of such imagery without which it is not much use in court.

 

But yes, every time you process an image or a video clip you lose some data so it is probable that all this processing has reduced the quality somewhat.

 

Chris Cosgrove



#6 trachys

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Posted 26 February 2018 - 07:30 PM

Okay. Fingers crossed that police forensics still have the original file, and the court will persuade them to give me a (decent) copy of it.

 

My thanks to all who replied.






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