BBC Audio Sync 'testcard'

[Ravi]

I couldn't find this posted elsewhere. If it has been, then forum mods please feel free to delete this thread.

This maybe of some use to people -
I noticed that as part of the BBC HD Preview - they sometimes broadcast a video testcard that has a video and audio cue that can be used for checking the two are synced up. I recorded 30 secs of this, and have found it useful in getting lipsync issues sorted, for example my PCs VLC media player was showing the video 1/10th of a second behind the audio. It was very easy to spot with this testcard, so you may like to record it too.

I'm not sure what time it gets broadcast - it was on about 12:30 on Monday. Either that, or I could upload the .ts file I have to somewhere (it's only 12MB in size)

 

[grahamlthompson]

There's a 5.1 channel level and speaker location test on the HD testcard as well.

 

[Ravi]

Thanks - I'll keep an eye out for it.

 

[Black Hole]

This has not been posted elsewhere as far as I know, thanks for bringing it up.

The human brain is generally far less comfortable when the sound arrives before vision (even by a very small amount) than the other way around - it's not something that could happen in nature. Strangely, one can tolerate a small lead until one notices it - and then it suddenly becomes intolerable!

It was a frequent occurrence to have the sync test broadcast on the BBC HiDef channels before regular programming came along, and I have to say it did not occur to me to record it.

 

[Ravi]

I also found this testcard good for tweeking the de-interlacing settings in VLC. Not it's intended purpose, of course. I now understand what the 'bob' setting actually does!

 

[xyz321]

It is interesting to look at the chalk lines on the blackboard when the HD testcard is being shown. If it is paused, the lines become 'stepped' which may suggest that it only displays one field in pause mode.