avfilter/formats: allow unknown channel layouts by default

Since the default in the libav fork is to only allow known layouts, making
unknown layouts allowed by default here can be a security risk for filters
directly merged from libav. However, usually it is simple to detect such cases,
use of av_get_channel_layout_nb_channels is a good indicator, so I suggest we
change this regardless.

See http://ffmpeg.org/pipermail/ffmpeg-devel/2016-November/203204.html.

This patch indirectly adds unknown channel layout support for filters where
query_formats is not specified:

abench
afifo
ainterleave
anullsink
apad
aperms
arealtime
aselect
asendcmd
asetnsamples
asetpts
asettb
ashowinfo
azmq

It introduces a query_formats callback for the asyncts filter, which only
supports known channel layouts since it is using libavresample.

And it removes .query_formats callback from filters where it was only there to
support unknown layouts, as this is now the default:

aloop
ametadata
anull
asidedata
asplit
atrim

Acked-by: Nicolas George <george@nsup.org>
Signed-off-by: Marton Balint <cus@passwd.hu>

1 files changed, 3 insertions, 3 deletions

diff --git a/libavfilter/formats.c b/libavfilter/formats.c
index 20f45e33cc..840780d562 100644
--- a/libavfilter/formats.c
+++ b/libavfilter/formats.c
@@ -596,12 +596,12 @@ static int default_query_formats_common(AVFilterContext *ctx,
 
 int ff_default_query_formats(AVFilterContext *ctx)
 {
-    return default_query_formats_common(ctx, ff_all_channel_layouts);
+    return default_query_formats_common(ctx, ff_all_channel_counts);
 }
 
-int ff_query_formats_all(AVFilterContext *ctx)
+int ff_query_formats_all_layouts(AVFilterContext *ctx)
 {
-    return default_query_formats_common(ctx, ff_all_channel_counts);
+    return default_query_formats_common(ctx, ff_all_channel_layouts);
 }
 
 /* internal functions for parsing audio format arguments */