[FFmpeg-devel] [PATCH]libavfilter/asrc_atone.c : generate algorithmic music

[Ashutosh Pradhan]

On Tue, Jun 30, 2020 at 8:40 PM Thilo Borgmann <thilo.borgmann at mail.de>
wrote:

> Am 30.06.20 um 16:09 schrieb Ashutosh Pradhan:
> > On Mon, Jun 29, 2020 at 6:53 PM Moritz Barsnick <barsnick at gmx.net>
> wrote:
> >
> >> On Thu, Jun 25, 2020 at 21:15:06 +0530, Ashutosh Pradhan wrote:
> >>> Generate algorithmic riff music. Changed to activate api.
> >>
> >> This commit doesn't change to activate API, as it introduces this
> >> filter. So that sentence doesn't belong here.
> >>
> >>>  - Real War KVAG muxer
> >>> -
> >>> +- atone filter
> >>
> >> Don't remove the empty line.
> >>
> >>>    --enable-libflite        enable flite (voice synthesis) support via
> >> libflite [no]
> >>> +  --enable-libfluidsynth   enable libfluidsynth support for fluidsynth
> >> [no]
> >>
> >> "for fluidsynth"?. Perhaps "for atone source".
> >>
> > Will change to above.
> >
> >>
> >>>  atempo_filter_select="rdft"
> >>> +atone_filter_deps="libfluidsynth"
> >>
> >>> + at item sfont
> >>> +Specify the location of soundfont file. Default value is
> >>> +"/usr/share/sounds/sf2/FluidR3_GM.sf2"(for linux).
> >>
> >> For Linux - and elsewhere?
> >> It will be the same path on all Unixes, but meaningless under Windows,
> >> I guess.
> >>
> > Yes.
> > Windows doesn't have the recommended Fluid_R3 General Midi SoundFont
> file.
> > So one has to enter the path every time.
> >
> >>
> >>> +++ b/libavfilter/Makefile
> >>> @@ -152,6 +152,7 @@ OBJS-$(CONFIG_FLITE_FILTER)                  +=
> >> asrc_flite.o
> >>>  OBJS-$(CONFIG_HILBERT_FILTER)                += asrc_hilbert.o
> >>>  OBJS-$(CONFIG_SINC_FILTER)                   += asrc_sinc.o
> >>>  OBJS-$(CONFIG_SINE_FILTER)                   += asrc_sine.o
> >>> +OBJS-$(CONFIG_ATONE_FILTER)                  += asrc_atone.o
> >>
> >> I believe the audio sources are meant to be sorted alphabetically (by
> >> CONFIG_*).
> >>
> >>> --- a/libavfilter/allfilters.c
> >>> +++ b/libavfilter/allfilters.c
> >>> @@ -146,6 +146,7 @@ extern AVFilter ff_asrc_flite;
> >>>  extern AVFilter ff_asrc_hilbert;
> >>>  extern AVFilter ff_asrc_sinc;
> >>>  extern AVFilter ff_asrc_sine;
> >>> +extern AVFilter ff_asrc_atone;
> >>
> >> Same here.
> >>
> >>> +#include <float.h>
> >>
> >>> +    s->beat_dur = 60000/s->beats_pm;
> >>> +    /*get change interval in frames/sec*/
> >>> +    s->changerate = (4*s->beat_dur)*s->sample_rate/s->nb_samples;
> >>> +    if (s->changerate<1.0)
> >>> +        s->changerate = 1.0;
> >>
> >> Please leave single spaces around the operators such as '/', '*', '<'.
> >>
> >>> +    s->numriffs = sizeof(riff)/(NPR* sizeof(int));
> >>
> >> Same here.
> >>
> >>> +    for (int i = 0; i < s->numriffs*NPR ; i++)
> >>
> >> And here.
> >>
> >>> +    if (s->framecount == INT_MAX)
> >>> +       s->framecount = 0;
> >>
> >> Indentation.
> >>
> >>> +    for (int i = 0; i <
> >> sizeof(GM_instrument_list)/sizeof(GM_instrument_list[0]); i++)
> >>
> >> Use macro FF_ARRAY_ELEMS
> >>
> >>> +        if (strcmp(GM_instrument_list[i], instrument) == 0)
> >>> +            return i;
> >>> +
> >>> +    return 0;
> >>> +}
> >>
> >> If this doesn't match any string, it returns 0. It also returns 0 if it
> >> matches "Acoustic-Grand". Is that correct? (In find_percussion_track(),
> >> you return i instead.)
> >>
> > I didn't want to output an error incase the instrument did not match. I
> > forgot to update 0 with the number of the default instrument. I will
> update
> > that.
>
> For that case, you might want to output a warning that the instrument
> could not be matched and the default instrument will be used instead.
>
I will change the code to implement this.

>
> >>
> >>> +static void schedule_noteon(int chan, short key, unsigned int ticks,
> >> int velocity, AtoneContext *s)
> >>> +{
> >>> +   fluid_event_t *ev = new_fluid_event();
> >>
> >> Indentation.
> >>
> >>> +    unsigned rand = av_lfg_get(&s->r)/2;
> >> [...]
> >>> +        riff = rand%s->numriffs;
> >>
> >> Spaces around operators, please.
> >>
> >>> +    if (3*i < numbars)
> >>> +        return (100 - (90*i)/numbars);
> >>> +    else if (3*i > 2*numbars)
> >>> +        return (40 + (90*i)/numbars);
> >>
> >> Same here.
> >>
> >>> +/*Determine the pattern, tempo (to paly as 8th, 16th or 32nd notes)
> and
> >> add the riffs to sequencer
> >>
> >> "play"
> >>
> >>> +Refernce: http://peterlangston.com/Papers/amc.pdf */
> >>
> >> "Reference"
> >>
> >>> +    AVFrame *frame;
> >>> +    int  nb_samples;
> >>           ^^ two spaces, drop one.
> >>
> >>> +    ret = ff_set_common_formats (ctx, formats);
> >>                                   ^ drop the space
> >>
> >>> +typedef struct
> >>> +{
> >>
> >> Bracket on the same line.
> >>
> >>> +Refernce: http://peterlangston.com/Papers/amc.pdf */
> >>
> >> "Reference".
> >>
>
> -Thilo
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".