On 9/24/15, Kyle Swanson <k...@ylo.ph> wrote:
> Sorry, I meant to type (1.0 / s->freq). This is one wavelength.
I inspected what filter produces with constant 0.5 mono input and
found it is repeating after each sample_rate number of samples.
Please do not top post.
>
> On Thu, Sep 24, 2015 at 9:29 AM, Kyle Swanson <k...@ylo.ph> wrote:
>>> s->table = av_malloc_array(inlink->sample_rate, sizeof(*s->table));
>>
>>
>> Just wondering. Is there a reason that the size of s->table is
>> (inlink->sample_rate) and not (1.0 / inlink->sample_rate) ?
>>
>> Thanks!
>> Kyle
>>
>> On Wed, Sep 23, 2015 at 6:16 PM, Kyle Swanson <k...@ylo.ph> wrote:
>>> Looks good. Thanks for the clean-up.
>>>
>>> On Wed, Sep 23, 2015 at 4:22 PM, Paul B Mahol <one...@gmail.com> wrote:
>>>> Signed-off-by: Paul B Mahol <one...@gmail.com>
>>>> ---
>>>> libavfilter/Makefile | 2 +-
>>>> libavfilter/af_tremolo.c | 45
>>>> ++++++++++++++++++++++-----------------------
>>>> 2 files changed, 23 insertions(+), 24 deletions(-)
>>>>
>>>> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
>>>> index 7054275..c70887e 100644
>>>> --- a/libavfilter/Makefile
>>>> +++ b/libavfilter/Makefile
>>>> @@ -85,7 +85,7 @@ OBJS-$(CONFIG_SILENCEREMOVE_FILTER) +=
>>>> af_silenceremove.o
>>>> OBJS-$(CONFIG_STEREOTOOLS_FILTER) += af_stereotools.o
>>>> OBJS-$(CONFIG_STEREOWIDEN_FILTER) += af_stereowiden.o
>>>> OBJS-$(CONFIG_TREBLE_FILTER) += af_biquads.o
>>>> -OBJS-$(CONFIG_TREMOLO_FILTER) += af_tremolo.o
>>>> generate_wave_table.o
>>>> +OBJS-$(CONFIG_TREMOLO_FILTER) += af_tremolo.o
>>>> OBJS-$(CONFIG_VOLUME_FILTER) += af_volume.o
>>>> OBJS-$(CONFIG_VOLUMEDETECT_FILTER) += af_volumedetect.o
>>>>
>>>> diff --git a/libavfilter/af_tremolo.c b/libavfilter/af_tremolo.c
>>>> index 6335401..0ae7a7c 100644
>>>> --- a/libavfilter/af_tremolo.c
>>>> +++ b/libavfilter/af_tremolo.c
>>>> @@ -22,15 +22,13 @@
>>>> #include "avfilter.h"
>>>> #include "internal.h"
>>>> #include "audio.h"
>>>> -#include "generate_wave_table.h"
>>>>
>>>> typedef struct TremoloContext {
>>>> const AVClass *class;
>>>> double freq;
>>>> double depth;
>>>> - double *wave_table;
>>>> - int wave_table_index;
>>>> - int sample_rate;
>>>> + double *table;
>>>> + int index;
>>>> } TremoloContext;
>>>>
>>>> #define OFFSET(x) offsetof(TremoloContext, x)
>>>> @@ -44,20 +42,11 @@ static const AVOption tremolo_options[] = {
>>>>
>>>> AVFILTER_DEFINE_CLASS(tremolo);
>>>>
>>>> -static double trem_env(AVFilterContext *ctx)
>>>> -{
>>>> - TremoloContext *s = ctx->priv;
>>>> - double env = s->wave_table[s->wave_table_index];
>>>> - s->wave_table_index++;
>>>> - if (s->wave_table_index >= s->sample_rate / s->freq)
>>>> - s->wave_table_index = 0;
>>>> - return 1.0 - (s->depth * env);
>>>> -}
>>>> -
>>>> static int filter_frame(AVFilterLink *inlink, AVFrame *in)
>>>> {
>>>> AVFilterContext *ctx = inlink->dst;
>>>> AVFilterLink *outlink = ctx->outputs[0];
>>>> + TremoloContext *s = ctx->priv;
>>>> const double *src = (const double *)in->data[0];
>>>> const int channels = inlink->channels;
>>>> const int nb_samples = in->nb_samples;
>>>> @@ -78,12 +67,13 @@ static int filter_frame(AVFilterLink *inlink,
>>>> AVFrame *in)
>>>> dst = (double *)out->data[0];
>>>>
>>>> for (n = 0; n < nb_samples; n++) {
>>>> - const double env = trem_env(ctx);
>>>> -
>>>> for (c = 0; c < channels; c++)
>>>> - dst[c] = src[c] * env;
>>>> + dst[c] = src[c] * s->table[s->index];
>>>> dst += channels;
>>>> src += channels;
>>>> + s->index++;
>>>> + if (s->index >= inlink->sample_rate)
>>>> + s->index = 0;
>>>> }
>>>>
>>>> if (in != out)
>>>> @@ -125,21 +115,30 @@ static int query_formats(AVFilterContext *ctx)
>>>> static av_cold void uninit(AVFilterContext *ctx)
>>>> {
>>>> TremoloContext *s = ctx->priv;
>>>> - av_freep(&s->wave_table);
>>>> + av_freep(&s->table);
>>>> }
>>>>
>>>> static int config_input(AVFilterLink *inlink)
>>>> {
>>>> AVFilterContext *ctx = inlink->dst;
>>>> TremoloContext *s = ctx->priv;
>>>> + const double offset = 1. - s->depth / 2.;
>>>> + int i;
>>>>
>>>> - s->sample_rate = inlink->sample_rate;
>>>> - s->wave_table = av_malloc_array(s->sample_rate / s->freq,
>>>> sizeof(*s->wave_table));
>>>> - if (!s->wave_table)
>>>> + s->table = av_malloc_array(inlink->sample_rate, sizeof(*s->table));
>>>> + if (!s->table)
>>>> return AVERROR(ENOMEM);
>>>>
>>>> - ff_generate_wave_table(WAVE_SIN, AV_SAMPLE_FMT_DBL, s->wave_table,
>>>> s->sample_rate / s->freq, 0.0, 1.0, 0.0);
>>>> - s->wave_table_index = 0;
>>>> + for (i = 0; i < inlink->sample_rate; i++) {
>>>> + double env = s->freq * i / inlink->sample_rate;
>>>> +
>>>> + env = sin(2 * M_PI * fmod(env + 0.25, 1.0));
>>>> +
>>>> + s->table[i] = env * (1 - fabs(offset)) + offset;
>>>> + }
>>>> +
>>>> + s->index = 0;
>>>> +
>>>> return 0;
>>>> }
>>>>
>>>> --
>>>> 1.9.1
>>>>
>>>> _______________________________________________
>>>> ffmpeg-devel mailing list
>>>> ffmpeg-devel@ffmpeg.org
>>>> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
