avfilter: add SOFAlizer audio filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Changelog

@@ -44,6 +44,7 @@ version <next>:
 - mips32r5 option has been removed
 - mips64r6 option has been removed
 - DXVA2-accelerated VP9 decoding
+- SOFAlizer: virtual binaural acoustics filter
 
 
 version 2.8:

configure

@@ -279,6 +279,7 @@ External library support:
   --disable-lzma           disable lzma [autodetect]
   --enable-decklink        enable Blackmagic DeckLink I/O support [no]
   --enable-mmal            enable decoding via MMAL [no]
+  --enable-netcdf          enable NetCDF, needed for sofalizer filter [no]
   --enable-nvenc           enable NVIDIA NVENC support [no]
   --enable-openal          enable OpenAL 1.1 capture support [no]
   --enable-opencl          enable OpenCL code
@@ -1503,6 +1504,7 @@ EXTERNAL_LIBRARY_LIST="
     libzvbi
     lzma
     mmal
+    netcdf
     nvenc
     openal
     opencl
@@ -2890,6 +2892,7 @@ showfreqs_filter_deps="avcodec"
 showfreqs_filter_select="fft"
 showspectrum_filter_deps="avcodec"
 showspectrum_filter_select="rdft"
+sofalizer_filter_deps="netcdf"
 spp_filter_deps="gpl avcodec"
 spp_filter_select="fft idctdsp fdctdsp me_cmp pixblockdsp"
 stereo3d_filter_deps="gpl"
@@ -5494,6 +5497,7 @@ enabled mmal              && { check_lib interface/mmal/mmal.h mmal_port_connect
                                     check_lib interface/mmal/mmal.h mmal_port_connect ; }
                                 check_lib interface/mmal/mmal.h mmal_port_connect ; } ||
                                die "ERROR: mmal not found"; }
+enabled netcdf            && require_pkg_config netcdf netcdf.h nc_inq_libvers
 enabled nvenc             && { check_header nvEncodeAPI.h || die "ERROR: nvEncodeAPI.h not found."; } &&
                              { check_cpp_condition nvEncodeAPI.h "NVENCAPI_MAJOR_VERSION >= 5" ||
                                die "ERROR: NVENC API version 4 or older is not supported"; } &&

doc/filters.texi

@@ -2889,6 +2889,35 @@ silenceremove=1:5:0.02
 @end example
 @end itemize
 
+@section sofalizer
+
+SOFAlizer uses head-related transfer functions (HRTFs) to create virtual
+loudspeakers around the user for binaural listening via headphones (audio
+formats up to 9 channels supported).
+The HRTFs are stored in SOFA files (see www.sofacoustics.org for a database).
+SOFAlizer is developed at the Acoustics Research Institute (ARI) of the
+Austrian Academy of Sciences.
+
+The filter accepts the following options:
+
+@table @option
+@item sofa
+Set the SOFA file used for rendering.
+
+@item gain
+Set gain applied to audio. Value is in dB. Default is 0.
+
+@item rotation
+Set rotation of virtual loudspeakers in deg. Default is 0.
+
+@item elevation
+Set elevation of virtual speakers in deg. Default is 0.
+
+@item radius
+Set distance in meters between loudspeakers and the listener with near-field
+HRTFs. Default is 1.
+@end table
+
 @section stereotools
 
 This filter has some handy utilities to manage stereo signals, for converting

libavfilter/Makefile

@@ -87,6 +87,7 @@ OBJS-$(CONFIG_SIDECHAINCOMPRESS_FILTER)      += af_sidechaincompress.o
 OBJS-$(CONFIG_SIDECHAINGATE_FILTER)          += af_agate.o
 OBJS-$(CONFIG_SILENCEDETECT_FILTER)          += af_silencedetect.o
 OBJS-$(CONFIG_SILENCEREMOVE_FILTER)          += af_silenceremove.o
+OBJS-$(CONFIG_SOFALIZER_FILTER)              += af_sofalizer.o
 OBJS-$(CONFIG_STEREOTOOLS_FILTER)            += af_stereotools.o
 OBJS-$(CONFIG_STEREOWIDEN_FILTER)            += af_stereowiden.o
 OBJS-$(CONFIG_TREBLE_FILTER)                 += af_biquads.o

libavfilter/allfilters.c

@@ -109,6 +109,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(SIDECHAINGATE,  sidechaingate,  af);
     REGISTER_FILTER(SILENCEDETECT,  silencedetect,  af);
     REGISTER_FILTER(SILENCEREMOVE,  silenceremove,  af);
+    REGISTER_FILTER(SOFALIZER,      sofalizer,      af);
     REGISTER_FILTER(STEREOTOOLS,    stereotools,    af);
     REGISTER_FILTER(STEREOWIDEN,    stereowiden,    af);
     REGISTER_FILTER(TREBLE,         treble,         af);

libavfilter/formats.c

@@ -289,6 +289,17 @@ AVFilterFormats *ff_make_format_list(const int *fmts)
     return formats;
 }
 
+AVFilterChannelLayouts *ff_make_formatu64_list(const uint64_t *fmts)
+{
+    MAKE_FORMAT_LIST(AVFilterChannelLayouts,
+                     channel_layouts, nb_channel_layouts);
+    if (count)
+        memcpy(formats->channel_layouts, fmts,
+               sizeof(*formats->channel_layouts) * count);
+
+    return formats;
+}
+
 AVFilterChannelLayouts *avfilter_make_format64_list(const int64_t *fmts)
 {
     MAKE_FORMAT_LIST(AVFilterChannelLayouts,

libavfilter/formats.h

@@ -141,6 +141,9 @@ AVFilterChannelLayouts *ff_all_channel_counts(void);
 av_warn_unused_result
 AVFilterChannelLayouts *avfilter_make_format64_list(const int64_t *fmts);
 
+av_warn_unused_result
+AVFilterChannelLayouts *ff_make_formatu64_list(const uint64_t *fmts);
+
 
 /**
  * A helper for query_formats() which sets all links to the same list of channel

libavfilter/version.h

@@ -30,7 +30,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   6
-#define LIBAVFILTER_VERSION_MINOR  20
+#define LIBAVFILTER_VERSION_MINOR  21
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \