Merged revisions 46329 via svnmerge from

Merged revisions 46329 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r46329 | russell | 2006-10-26 11:31:05 -0500 (Thu, 26 Oct 2006) | 11 lines

- If the source has no audio or no video portion, do not call powerof() to
  get the format index.
- Don't run through the audio and video loops if there is no audio or video
  portion of the source
If 0 is passed to powerof, it will return -1.  This value of -1 was then being
used as an array index in these loops, which caused a crash on some systems.
Other than this issue, this code works as we expected it to.  If a format is
not in the source, and we have to translation path to it, it is not offered in
the list of acceptable destination formats.
(fixes issue #8231)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@46330 65c4cc65-6c06-0410-ace0-fbb531ad65f3