3 replies to this topic

[chafpa]

After editing the recordings to remove commercial advertisements, during playback I systematically have a brief black screen that appears after each cut.

I have had this anomaly for a few months. Before, it worked flawlessly.

What is causing this black screen ?

I'm with a Vu+ Duo 4K SE and OpenPli 9 up to date.

Thanks for any advice.

 

Edit : Translated by Google translate.

[WanWizard]

It is normal for some channels that there is a black frame at the start and at the end of every commercial block.

 

Cutting also never happens exactly where you would want it, it needs an MPEG I-frame, not P or B frames. How many I frames there are, and at which interval, depends on the compressors used by the channel, i.e. how compressed the video is. So maybe that changed?

 

How long is "brief"? If it is longer than "a flash on screen", something else is the matter...

[chafpa]

I don't remember having black screens before or after an outage.

I write 'brief', it's certainly less than a second.

[WanWizard]

I know of no other reason. The cut editor searches for the first I-frame after the cut point, and cuts until the first I-frame after the second cut point, and removes the section in between.

 

Where I-frames are in the stream depends on the method and equipment (and the configuration of that equipment) of compression.

 

This is why for example recorded streams are so difficult to cut, they are often so compressed that there are many seconds, sometimes even minutes, between two I-frames.