Intro files, etc.

[hhb]

Hello, have been fiddling with a rudimentary intro file for a live stream because using the intro file displays the same transition problem as what happens when switching channels on a wireless receiver for live streams.

Pink squares, other extraneous stuff, jumping around for one half to 3 or 4 seconds while the stream goes from intro file to live stream. The channel switch problem is brief -- one second at most -- and usually, it's clean, but the mess for that one second when the problem occurs looks exactly like the intro transition problem. What causes the signal jumble, and is there a remedy?

Have no need for an intro file really, but if a fix for its transition problem would also work for switching live receiver channels, would be in clover ....

Thanks for any help/info -- hhb

[B0b]

You need to have "key frames" more often.

[hhb]

Thanks for this tip. Am encoding at 300 KBS, VP6.1, 30 FPS. The scvi.net hint for VP6.2 config's max frames between keys is 255.

Re-encoded the intro file with 150 btw. Then streamed the live at same btw. This almost gets it -- lowers the pink garble to a fraction of a second and sometimes clean, even.

With btw set at this rate, encoding computer cpu rate doesn't go up, bandwidth is still under target (at least with this rather still test scene). The only consequence of lowering btw that I can see is that the intro file is larger, of course, but with a live stream, not a factor.

Edit 15 min later: Tried 100 btw with intro and live test stream. Smooth as glass with no real tradeoffs that I can see yet. The channel switch oughta work, too. Thanks.

hhb

[B0b]

Originally posted by hhb
Thanks.

hhb

Np. Invoice is in the mail.

BTW, you only need to increase the key frame frequency for the content which you are switching to, not from.

[hhb]

Thanks again. Live channels have to be the same btw, of course, but useful to know about the "from" part. Keeping an eye out for that invoice.

hhb

[john@ROCKNTV1]

I also have been workimg toward smoothing out the transition
between intro and stream.THE shear amount of variables to consider during encoding ie:video ,static,high motion,amount
of lighting and even the complexity of the audio,has forced me to encode my intro files on a PER USE basis.
Meaning, because most of my vid is prerecorded ,i redo my intro till it works,pulling ,adding kbps till it works right.The advanced settings in the vp6 codec are all important , the min/max between keys, for me is frame rate/
twice frame rate.auto key frame ,unchecked ,max between keys
is 1 frame less than per second frame rate. Not realy sure why this works, but i am constantly trying diff combos to have my stream look its best. unfortunatly i think streams @
150 KBPS or less are likely to disatisfy ,me any way

JOHN

[hhb]

Below works consistently here for live ....

VP6.1 at 250 KBS
25 FPS
320 x 240 res
scvi.net configs for VP6.2 except btw
100 max frames btw keys
Audio - 32 KBS stereo/Raw AAC

Intro file is same. Tried different btw, 125 almost got it but 100 makes no errors at all, a clean switch every time.

Tested with an intro to get it right for the live channel switches, as said above, and the config works for that too. 300 KBS/30 FPS does okay with it, would prefer that, but dropped down because a secondary cam here dines on bitrate. Barely stays under max while others are mostly well below max. Don't know enough to even think about why. All the same class, all streaming similar scenes.

Testing done inside, very different from busy, moving scenes outdoors -- waving blades of grass/blowing tree leaves in wide views shoot the bitrate right up there. The dropdown might be a good cushion for that. If it ever stops raining, will see what happens.

Hang in there -- hhb