lavf: fix update_initial_durations() so it handles missing durations with the initial...

[ffmpeg] / doc / faq.texi

diff --git a/doc/faq.texi b/doc/faq.texi
index fb180fbbf1dad4f020818da38de6b941abc35482..5f371a45463ebe7a834657506e222ec8c208cb64 100644 (file)
--- a/doc/faq.texi
+++ b/doc/faq.texi
@@ -292,6 +292,24 @@ The solution is to apply the @option{-profile} option to the video stream only
 by using @url{http://ffmpeg.org/ffmpeg.html#Stream-specifiers-1, Stream specifiers}.
 Appending @code{:v} to it will do exactly that.
 
+@section Using @option{-f lavfi}, audio becomes mono for no apparent reason.
+
+Use @option{-dumpgraph -} to find out exactly where the channel layout is
+lost.
+
+Most likely, it is through @code{auto-inserted aconvert}. Try to understand
+why the converting filter was needed at that place.
+
+Just before the output is a likely place, as @option{-f lavfi} currently
+only support packed S16.
+
+Then insert the correct @code{aconvert} explicitly in the filter graph,
+specifying the exact format.
+
+@example
+aconvert=s16:stereo:packed
+@end example
+
 @chapter Development
 
 @section Are there examples illustrating how to use the FFmpeg libraries, particularly libavcodec and libavformat?
@@ -397,4 +415,16 @@ wrong if it is larger than the average!
 For example, if you have mixed 25 and 30 fps content, then r_frame_rate
 will be 150.
 
+@section Why is @code{make fate} not running all tests?
+
+Make sure you have the fate-suite samples and the @code{SAMPLES} Make variable
+or @code{FATE_SAMPLES} environment variable or the @code{--samples}
+@command{configure} option is set to the right path.
+
+@section Why is @code{make fate} not finding the samples?
+
+Do you happen to have a @code{~} character in the samples path to indicate a
+home directory? The value is used in ways where the shell cannot expand it,
+causing FATE to not find files. Just replace @code{~} by the full path.
+
 @bye