Answers.Body: <p>Generally no. Compression algorithms search for repetitive data and replace it with a shorter code and keep a dictionary with all codes. Compressing text works excellent because in longer texts a lot of words repeat. </p>
  
  <p>With video this work has been done most of the time already. Usually the encoder is  performing a similar operation: looking for repeating patterns and replacing them with a shorter code. Most video files you see are already compressed, most repetitive patterns already encoded and therefore any further compression won't do much.</p>
  
  <p>Sometimes re-encoding videos with a much newer encoder saves a lot of space, but this process is always a bit lossy and requires more work.</p>
  
  <p>You could check if the files have any additional unwanted audio tracks and remove them, like tracks in languages you don't speak anyway.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-04T06:45:30.453Z
Answers.Text: Many thanks Matt
Answers.UserDisplayName: geo667
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-03T20:47:53.107Z
Answers.LastActivityDate: 2020-06-03T20:47:53.107Z
Answers.UserDisplayName: Matt
Body: <p>I want to compress a video to store it for backup purpose.</p>
  
  <p>By that, I mean that I don't need to play video when it is compress format. So I don't want to lose quality or something like that, just compress it.</p>
  
  <p>I have tried to compress with 7zip, but size not decrease. Is it possible to compress a video ? </p>
  
  <p>For example, I use 7zip on a 3.92Go mkv video. I try :</p>
  
  <ul>
  <li>zip format : 3.92Go</li>
  <li>gz format : 3.88Go</li>
  </ul>
  
Tags: <compression>
Title: compress video for backup
UserDisplayName: geo667
ThreadText: # compress video for backup
  
  (Asked by: username_0 on 2020-06-03)
  
  I want to compress a video to store it for backup purpose.
  
  By that, I mean that I don't need to play video when it is compress format. So I don't want to lose quality or something like that, just compress it.
  
  I have tried to compress with 7zip, but size not decrease. Is it possible to compress a video ?
  
  For example, I use 7zip on a 3.92Go mkv video. I try :
  
  * zip format : 3.92Go
  * gz format : 3.88Go
  
  **Tags:** compression
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2020-06-03. Score: 1 | Accepted answer
  
  Generally no. Compression algorithms search for repetitive data and replace it with a shorter code and keep a dictionary with all codes. Compressing text works excellent because in longer texts a lot of words repeat.
  
  With video this work has been done most of the time already. Usually the encoder is performing a similar operation: looking for repeating patterns and replacing them with a shorter code. Most video files you see are already compressed, most repetitive patterns already encoded and therefore any further compression won't do much.
  
  Sometimes re-encoding videos with a much newer encoder saves a lot of space, but this process is always a bit lossy and requires more work.
  
  You could check if the files have any additional unwanted audio tracks and remove them, like tracks in languages you don't speak anyway.
  
  > **Comments:**
  > **username_0**: Many thanks username_1  
  
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