Is it possible to get the innside part envelope of the signal

I have a signal with a lot of peaks. what i want to achieve is to get the envelope of inner part of the signal, the one of that part that looks solid in colors not the peaks envelope is it possible to achieve this.

like the one in the picture <https://docs.google.com/file/d/0B61s6H8F7eyNZUhFQ0RfVzZxRFU/edit?usp=sharing>

Thank You

[José-Luis]

It will look solid or not depending on your y-scale, so there is no straightforward way to answer that part of the question. Otherwise it looks like you are thinking about smoothing. For that, please look at:

 doc smooth
 doc conv
 doc filter

[DuckDuck]

i tried with smooth but still the peaks are shown in the envelope. with filter i tried with butter and it was more ore less similar to smooth except from shifting to the right in butter. I'm really stacked in here :(

[José-Luis]

You could try different weights and lengths for the smoothing until you get something that looks like what you'd like. The easiest way however would probably be to ask the person that generated that plot.

To avoid giving much weight to the peaks, you could also try with a median filter:

 doc medfilt1

[DuckDuck]

It was me who generated that plot, the signal inside the blue surface is a signal from other sensors, but i noticed it has the shape of the inner envelope of the blue one. so i thought i could find a way to generate it from the blue signal. The mdfilt1 didn't give me any thing useful. But thanks for your effort.