What are previews used for?

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Keith
Posts: 1
Joined: Sat Jan 24, 2015 7:56 am

What are previews used for?

Post by Keith »

I figured previews are useless when you're not using the gui, so I added --previews=0:0 to my handbrakecli script and it responded by giving me "libhb: scan thread found 0 valid title(s)". It took me quite a while to figure out that the change I made was what was causing the command to fail.

So, what IS handbrake doing with previews such that they are required even when running from the command line?
Smithcraft
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Re: What are previews used for?

Post by Smithcraft »

Handbrake is scanning the file to determine the cropping values, and maybe some other things that it might need to know about the file when it's doing the preview scans.

SC
AlBundy
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Re: What are previews used for?

Post by AlBundy »

Is this really necessary because sometimes it takes really long to create the previews?
In my case I've disabled autocropping.

Al
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s55
HandBrake Team
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Re: What are previews used for?

Post by s55 »

You can't disable. At best you can turn it down to a low number.
AlBundy
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Re: What are previews used for?

Post by AlBundy »

Are there any sideeffects if I disable autocrop and turn down the previews?

Al
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s55
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Re: What are previews used for?

Post by s55 »

no.
Deleted User 11865

Re: What are previews used for?

Post by Deleted User 11865 »

Yes, framerate detection will be less accurate (i.e. won't be adjusted for soft telecine), and if you have less than 5 previews, some very rare sources might fail to scan sometimes.
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