Since this function adds a standalone filter to a filter graph and we do
not support creating such filters, there is no reason for this function
to exist.
Since we do not support "standalone" filters not attached to an
AVFilterGraph, we should not have a public function to create such
filters. In addition that function is horribly named, the action it does
cannot be possibly described as "opening" a filter.
The warning is:
libavfilter/avfiltergraph.c: In function ‘avfilter_graph_config’:
libavfilter/avfiltergraph.c:528:9: warning: ‘best_idx’ may be used uninitialized in this function [-Wuninitialized]
libavfilter/avfiltergraph.c:479:13: note: ‘best_idx’ was declared here
Initialize it to an invalid value and add an assert that it's properly
set later.
Allow substitution of channel pairs in the input for nearby channel pairs in
the output in order to get a closer match. Also weigh LFE channel mismatch
differently to favor matching the same layout without LFE over one less
channel with LFE.
The warning silenced was:
libavfilter/avfiltergraph.c: In function ‘avfilter_graph_config’:
libavfilter/avfiltergraph.c:500:13: warning: ‘best_idx’ may be used uninitialized in this function [-Wuninitialized]
Current code, with a filterchain such as
(input - yuv411) -> (scale - any) -> (sink - any)
will result in yuv420 being chosen for the second link, which is clearly
not right.
This commit attempts to improve in the following way:
repeat until convergence:
loop over all filters
find input link with exactly one format
force this format on all output links of the same type (if possible)
Make avfilter_graph_free() free not only the internal structures, but
also the allocated graph, and set the graph pointer to NULL for
increased safety.
Simplify usage.
Signed-off-by: Mans Rullgard <mans@mansr.com>
ff_avfilter_graph_check_validity()
ff_avfilter_graph_config_links()
ff_avfilter_graph_config_formats()
and move their declaration to internal.h. These functions are never
used in application code, so it is better to consider them internal
functions, this can be changed later if necessary. Simplify API.
Originally committed as revision 25737 to svn://svn.ffmpeg.org/ffmpeg/trunk