Thumbnail generation - design problem: thumbnails are almost same and not very informative. (1 Viewer)

[Sebastiii]

I think it's not only your system, i remember seeing that too on big files.
Thumbnail should be quick as much as possible

 

[infinite.loop]

Something like: get the max playtime of the video, and use that for the thumbnail point calculation - unless playtime is longer than 30 minutes -> then take 30 minutes as playtime for the calculation?

 

[tourettes]

Hi,

there is a performance issue to seeking the big files (longer than 30 mins) in my system. I think, not a good idea to seek the full file for thumbs. What about to limit the duration value?

I bet performance is 99% the same with 29 min files and 98% same with 28 min files. What happens is the file probably needs to be decoded on some level (probably the seeing algorithm is bad so it cannot find the correct positions like TsReader ).

 

[regeszter]

Something like: get the max playtime of the video, and use that for the thumbnail point calculation - unless playtime is longer than 30 minutes -> then take 30 minutes as playtime for the calculation?

Yes, that is my opinion.[DOUBLEPOST=1373286478][/DOUBLEPOST]

Hi,

there is a performance issue to seeking the big files (longer than 30 mins) in my system. I think, not a good idea to seek the full file for thumbs. What about to limit the duration value?

I bet performance is 99% the same with 29 min files and 98% same with 28 min files. What happens is the file probably needs to be decoded on some level (probably the seeing algorithm is bad so it cannot find the correct positions like TsReader ).

The original version (1.4.0) made the thumbs in the 1st minutes of the file instead of jump to 10-20 minutes to seek the full file. I understand the 1st minutes not to informative but seeking a 1-2 hours video is too slow.

 

[tourettes]

The original version (1.4.0) made the thumbs in the 1st minutes of the file instead of jump to 10-20 minutes to seek the full file. I understand the 1st minutes not to informative but seeking a 1-2 hours video is too slow.

Seeking to 1 hour mark should be as fast as 30 minute, unles there is something broken in the thumbnailer code.

 

[Sebastiii]

It's more ffmpeg code i would say, i remember doing that with command line and take some times on .ts files (i suppose too on other format)

 

[regeszter]

The thumbnail generator uses ffmpeg to extract tumbs from video. I can reproduce the issue in command line so it is not MP related issue.

 

[tourettes]

The thumbnail generator uses ffmpeg to extract tumbs from video. I can reproduce the issue in command line so it is not MP related issue.

Sounds like ffmpeg.exe is stupid and decodes the whole file up to the point where it is asked to seek. Not sure thou, but cannot think any other explanation.

 

[infinite.loop]

The thumbnail generator uses ffmpeg to extract tumbs from video. I can reproduce the issue in command line so it is not MP related issue.

Is that a recent version of ffmpeg?

 

[regeszter]

Yes,

The thumbnail generator uses ffmpeg to extract tumbs from video. I can reproduce the issue in command line so it is not MP related issue.

Is that a recent version of ffmpeg?

Yes, I tested it with latest ffmpeg.exe


Here is a new version.

Change log:

• If Duration>30 mins, Duration = 30 mins.
• When have to get 1x1 thumbnail, it will be extract on Time Offset (fast)
• When have to get 1x2 or 2x1 thumbnail, it will be extract on Time Offset and + 33%
• When have to get 2x2 thumbnail, it will be extract on Time Offset and + 20%, + 20%, +20% (slow)
• Applied "Fix regression introduce from Mantis #3920" Thanks Sebastiii!