Commit 653f9d84 authored by Paul B Mahol's avatar Paul B Mahol

avfilter: add spectrumsynth filter

Signed-off-by: 's avatarPaul B Mahol <onemda@gmail.com>
parent cc538e9d
...@@ -52,6 +52,7 @@ version <next>: ...@@ -52,6 +52,7 @@ version <next>:
- automatic bitstream filtering - automatic bitstream filtering
- showspectrumpic filter - showspectrumpic filter
- libstagefright support removed - libstagefright support removed
- spectrumsynth filter
version 2.8: version 2.8:
......
...@@ -2903,6 +2903,8 @@ showspectrumpic_filter_deps="avcodec" ...@@ -2903,6 +2903,8 @@ showspectrumpic_filter_deps="avcodec"
showspectrumpic_filter_select="fft" showspectrumpic_filter_select="fft"
sofalizer_filter_deps="netcdf avcodec" sofalizer_filter_deps="netcdf avcodec"
sofalizer_filter_select="fft" sofalizer_filter_select="fft"
spectrumsynth_filter_deps="avcodec"
spectrumsynth_filter_select="fft"
spp_filter_deps="gpl avcodec" spp_filter_deps="gpl avcodec"
spp_filter_select="fft idctdsp fdctdsp me_cmp pixblockdsp" spp_filter_select="fft idctdsp fdctdsp me_cmp pixblockdsp"
stereo3d_filter_deps="gpl" stereo3d_filter_deps="gpl"
...@@ -6081,6 +6083,7 @@ enabled sofalizer_filter && prepend avfilter_deps "avcodec" ...@@ -6081,6 +6083,7 @@ enabled sofalizer_filter && prepend avfilter_deps "avcodec"
enabled showfreqs_filter && prepend avfilter_deps "avcodec" enabled showfreqs_filter && prepend avfilter_deps "avcodec"
enabled showspectrum_filter && prepend avfilter_deps "avcodec" enabled showspectrum_filter && prepend avfilter_deps "avcodec"
enabled smartblur_filter && prepend avfilter_deps "swscale" enabled smartblur_filter && prepend avfilter_deps "swscale"
enabled spectrumsynth_filter && prepend avfilter_deps "avcodec"
enabled subtitles_filter && prepend avfilter_deps "avformat avcodec" enabled subtitles_filter && prepend avfilter_deps "avformat avcodec"
enabled uspp_filter && prepend avfilter_deps "avcodec" enabled uspp_filter && prepend avfilter_deps "avcodec"
......
...@@ -14578,6 +14578,7 @@ Default is @code{combined}. ...@@ -14578,6 +14578,7 @@ Default is @code{combined}.
@end table @end table
@anchor{showspectrum}
@section showspectrum @section showspectrum
Convert input audio to a video output, representing the audio frequency Convert input audio to a video output, representing the audio frequency
...@@ -15003,6 +15004,68 @@ ffmpeg -i audio.mp3 -filter_complex "showwavespic,colorchannelmixer=rr=66/255:gg ...@@ -15003,6 +15004,68 @@ ffmpeg -i audio.mp3 -filter_complex "showwavespic,colorchannelmixer=rr=66/255:gg
@end example @end example
@end itemize @end itemize
@section spectrumsynth
Sythesize audio from 2 input video spectrums, first input stream represents
magnitude across time and second represents phase across time.
The filter will transform from frequency domain as displayed in videos back
to time domain as presented in audio output.
This filter is primarly created for reversing processed @ref{showspectrum}
filter outputs, but can synthesize sound from other spectrograms too.
But in such case results are going to be poor if the phase data is not
available, because in such cases phase data need to be recreated, usually
its just recreated from random noise.
For best results use gray only output (@code{channel} color mode in
@ref{showspectrum} filter) and @code{log} scale for magnitude video and
@code{lin} scale for phase video. To produce phase, for 2nd video, use
@code{data} option. Inputs videos should generally use @code{fullframe}
slide mode as that saves resources needed for decoding video.
The filter accepts the following options:
@table @option
@item sample_rate
Specify sample rate of output audio, the sample rate of audio from which
spectrum was generated may differ.
@item channels
Set number of channels represented in input video spectrums.
@item scale
Set scale which was used when generating magnitude input spectrum.
Can be @code{lin} or @code{log}. Default is @code{log}.
@item slide
Set slide which was used when generating inputs spectrums.
Can be @code{replace}, @code{scroll}, @code{fullframe} or @code{rscroll}.
Default is @code{fullframe}.
@item win_func
Set window function used for resynthesis.
@item overlap
Set window overlap. In range @code{[0, 1]}. Default is @code{1},
which means optimal overlap for selected window function will be picked.
@item orientation
Set orientation of input videos. Can be @code{vertical} or @code{horizontal}.
Default is @code{vertical}.
@end table
@subsection Examples
@itemize
@item
First create magnitude and phase videos from audio, assuming audio is stereo with 44100 sample rate,
then resynthesize videos back to audio with spectrumsynth:
@example
ffmpeg -i input.flac -lavfi showspectrum=mode=separate:scale=log:overlap=0.875:color=channel:slide=fullframe:data=magnitude -an -c:v rawvideo magnitude.nut
ffmpeg -i input.flac -lavfi showspectrum=mode=separate:scale=lin:overlap=0.875:color=channel:slide=fullframe:data=phase -an -c:v rawvideo phase.nut
ffmpeg -i magnitude.nut -i phase.nut -lavfi spectrumsynth=channels=2:sample_rate=44100:win_fun=hann:overlap=0.875:slide=fullframe output.flac
@end example
@end itemize
@section split, asplit @section split, asplit
Split input into several identical outputs. Split input into several identical outputs.
......
...@@ -290,6 +290,7 @@ OBJS-$(CONFIG_SHOWSPECTRUMPIC_FILTER) += avf_showspectrum.o window_func.o ...@@ -290,6 +290,7 @@ OBJS-$(CONFIG_SHOWSPECTRUMPIC_FILTER) += avf_showspectrum.o window_func.o
OBJS-$(CONFIG_SHOWVOLUME_FILTER) += avf_showvolume.o OBJS-$(CONFIG_SHOWVOLUME_FILTER) += avf_showvolume.o
OBJS-$(CONFIG_SHOWWAVES_FILTER) += avf_showwaves.o OBJS-$(CONFIG_SHOWWAVES_FILTER) += avf_showwaves.o
OBJS-$(CONFIG_SHOWWAVESPIC_FILTER) += avf_showwaves.o OBJS-$(CONFIG_SHOWWAVESPIC_FILTER) += avf_showwaves.o
OBJS-$(CONFIG_SPECTRUMSYNTH_FILTER) += vaf_spectrumsynth.o window_func.o
# multimedia sources # multimedia sources
OBJS-$(CONFIG_AMOVIE_FILTER) += src_movie.o OBJS-$(CONFIG_AMOVIE_FILTER) += src_movie.o
......
...@@ -310,6 +310,7 @@ void avfilter_register_all(void) ...@@ -310,6 +310,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(SHOWVOLUME, showvolume, avf); REGISTER_FILTER(SHOWVOLUME, showvolume, avf);
REGISTER_FILTER(SHOWWAVES, showwaves, avf); REGISTER_FILTER(SHOWWAVES, showwaves, avf);
REGISTER_FILTER(SHOWWAVESPIC, showwavespic, avf); REGISTER_FILTER(SHOWWAVESPIC, showwavespic, avf);
REGISTER_FILTER(SPECTRUMSYNTH, spectrumsynth, vaf);
/* multimedia sources */ /* multimedia sources */
REGISTER_FILTER(AMOVIE, amovie, avsrc); REGISTER_FILTER(AMOVIE, amovie, avsrc);
......
This diff is collapsed.
...@@ -30,7 +30,7 @@ ...@@ -30,7 +30,7 @@
#include "libavutil/version.h" #include "libavutil/version.h"
#define LIBAVFILTER_VERSION_MAJOR 6 #define LIBAVFILTER_VERSION_MAJOR 6
#define LIBAVFILTER_VERSION_MINOR 23 #define LIBAVFILTER_VERSION_MINOR 24
#define LIBAVFILTER_VERSION_MICRO 100 #define LIBAVFILTER_VERSION_MICRO 100
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \ #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
......
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