This should fix fate failures of the hecommon test
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Mans Rullgard <mans@mansr.com>

This allows fate to run without errors with or without SAMPLES
being set.
Signed-off-by: Mans Rullgard <mans@mansr.com>

This makes only tests actually using avconv depend on it.
The remaining tests already depend on what they need.
Signed-off-by: Mans Rullgard <mans@mansr.com>

related to b7165426
Error messages and audible artifacts were fixed in that commit.

instead of current "make output file of size less than ss".

Also use it to make MP3 tests more readable (using -fs xxx where xxx is
the requested output size, not something slightly lower).

Originally committed as revision 24884 to svn://svn.ffmpeg.org/ffmpeg/trunk

Originally committed as revision 24881 to svn://svn.ffmpeg.org/ffmpeg/trunk

Originally committed as revision 24880 to svn://svn.ffmpeg.org/ffmpeg/trunk