[gst-devel] could not link audiotestsrc0 to jackaudiosink0

[patrick]

> Try with this command
> # gst-launch-0.10 audiotestsrc ! audioconvert ! jackaudiotestsrc
>
> it may be a problem of pads compatibility, that hopefully audioconvert
> will solve for you

yes it works. thanks!
Daniel Lenski sent me this information:

Pat, you need an audioconvert in there: audiotestsrc ! audioconvert !
jackaudiosrc

Run gst-inspect on audiotestsrc and jackaudiosink and you'll see why:
$ gst-inspect audiotestsrc
Pad Templates:
  SRC template: 'src'
    Availability: Always
    Capabilities:
      audio/x-raw-int
             endianness: 1234
                 signed: true
                  width: 16
                  depth: 16
                   rate: [ 1, 2147483647 ]
               channels: 1
$ gst-inspect jackaudiosink
Pad Templates:
  SINK template: 'sink'
    Availability: Always
    Capabilities:
      audio/x-raw-float
             endianness: { 1234 }
                  width: 32
                   rate: [ 1, 2147483647 ]
               channels: [ 1, 2147483647 ]

Basically, audiotestsrc puts out integer raw audio, while jackaudiosrc
wants to receive floating point raw audio.  Audioconvert will
basically convert any raw audio format to any other.  You should
always put it in front of audio sinks, because the different drivers
accept different formats and it's impossible to remember which is
which... if they happen to be matched up as in the case of alsasink
and audiotestsrc, audioconvert simply passes the data through and adds
no overhead.