@@ -2576,6 +2576,13 @@ logarithmic (in octave scale where 20 Hz is 0) frequency, linear gain

 @item loglog

 logarithmic frequency, logarithmic gain

 @end table

+

+@item dumpfile

+Set file for dumping, suitable for gnuplot.

+

+@item dumpscale

+Set scale for dumpfile. Acceptable values are same with scale option.

+Default is linlog.

 @end table

 @subsection Examples

@@ -65,6 +65,7 @@ typedef struct {

 typedef struct {

     const AVClass *class;

+    RDFTContext   *analysis_rdft;

     RDFTContext   *analysis_irdft;

     RDFTContext   *rdft;

     RDFTContext   *irdft;

@@ -72,6 +73,7 @@ typedef struct {

     int           rdft_len;

     float         *analysis_buf;

+    float         *dump_buf;

     float         *kernel_tmp_buf;

     float         *kernel_buf;

     float         *conv_buf;

@@ -93,6 +95,8 @@ typedef struct {

     int           multi;

     int           zero_phase;

     int           scale;

+    char          *dumpfile;

+    int           dumpscale;

     int           nb_gain_entry;

     int           gain_entry_err;

@@ -126,6 +130,8 @@ static const AVOption firequalizer_options[] = {

         { "linlog", "linear-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LINLOG }, 0, 0, FLAGS, "scale" },

         { "loglin", "logarithmic-freq linear-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLIN }, 0, 0, FLAGS, "scale" },

         { "loglog", "logarithmic-freq logarithmic-gain", 0, AV_OPT_TYPE_CONST, { .i64 = SCALE_LOGLOG }, 0, 0, FLAGS, "scale" },

+    { "dumpfile", "set dump file", OFFSET(dumpfile), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, FLAGS },

+    { "dumpscale", "set dump scale", OFFSET(dumpscale), AV_OPT_TYPE_INT, { .i64 = SCALE_LINLOG }, 0, NB_SCALE-1, FLAGS, "scale" },

     { NULL }

 };

@@ -133,12 +139,14 @@ AVFILTER_DEFINE_CLASS(firequalizer);

 static void common_uninit(FIREqualizerContext *s)

 {

+    av_rdft_end(s->analysis_rdft);

     av_rdft_end(s->analysis_irdft);

     av_rdft_end(s->rdft);

     av_rdft_end(s->irdft);

-    s->analysis_irdft = s->rdft = s->irdft = NULL;

+    s->analysis_rdft = s->analysis_irdft = s->rdft = s->irdft = NULL;

     av_freep(&s->analysis_buf);

+    av_freep(&s->dump_buf);

     av_freep(&s->kernel_tmp_buf);

     av_freep(&s->kernel_buf);

     av_freep(&s->conv_buf);

@@ -223,6 +231,53 @@ static void fast_convolute(FIREqualizerContext *s, const float *kernel_buf, floa

     }

 }

+static void dump_fir(AVFilterContext *ctx, FILE *fp, int ch)

+{

+    FIREqualizerContext *s = ctx->priv;

+    int rate = ctx->inputs[0]->sample_rate;

+    int xlog = s->dumpscale == SCALE_LOGLIN || s->dumpscale == SCALE_LOGLOG;

+    int ylog = s->dumpscale == SCALE_LINLOG || s->dumpscale == SCALE_LOGLOG;

+    int x;

+    int center = s->fir_len / 2;

+    double delay = s->zero_phase ? 0.0 : (double) center / rate;

+    double vx, ya, yb;

+

+    s->analysis_buf[0] *= s->rdft_len/2;

+    for (x = 1; x <= center; x++) {

+        s->analysis_buf[x] *= s->rdft_len/2;

+        s->analysis_buf[s->analysis_rdft_len - x] *= s->rdft_len/2;

+    }

+

+    if (ch)

+        fprintf(fp, "\n\n");

+

+    fprintf(fp, "# time[%d] (time amplitude)\n", ch);

+

+    for (x = center; x > 0; x--)

+        fprintf(fp, "%15.10f %15.10f\n", delay - (double) x / rate, (double) s->analysis_buf[s->analysis_rdft_len - x]);

+

+    for (x = 0; x <= center; x++)

+        fprintf(fp, "%15.10f %15.10f\n", delay + (double)x / rate , (double) s->analysis_buf[x]);

+

+    av_rdft_calc(s->analysis_rdft, s->analysis_buf);

+

+    fprintf(fp, "\n\n# freq[%d] (frequency desired_gain actual_gain)\n", ch);

+

+    for (x = 0; x <= s->analysis_rdft_len/2; x++) {

+        int i = (x == s->analysis_rdft_len/2) ? 1 : 2 * x;

+        vx = (double)x * rate / s->analysis_rdft_len;

+        if (xlog)

+            vx = log2(0.05*vx);

+        ya = s->dump_buf[i];

+        yb = s->analysis_buf[i];

+        if (ylog) {

+            ya = 20.0 * log10(fabs(ya));

+            yb = 20.0 * log10(fabs(yb));

+        }

+        fprintf(fp, "%17.10f %17.10f %17.10f\n", vx, ya, yb);

+    }

+}

+

 static double entry_func(void *p, double freq, double gain)

 {

     AVFilterContext *ctx = p;

@@ -332,6 +387,7 @@ static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *g

     int ret, k, center, ch;

     int xlog = s->scale == SCALE_LOGLIN || s->scale == SCALE_LOGLOG;

     int ylog = s->scale == SCALE_LINLOG || s->scale == SCALE_LOGLOG;

+    FILE *dump_fp = NULL;

     s->nb_gain_entry = 0;

     s->gain_entry_err = 0;

@@ -352,10 +408,14 @@ static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *g

     if (ret < 0)

         return ret;

+    if (s->dumpfile && (!s->dump_buf || !s->analysis_rdft || !(dump_fp = fopen(s->dumpfile, "w"))))

+        av_log(ctx, AV_LOG_WARNING, "dumping failed.\n");

+

     vars[VAR_CHS] = inlink->channels;

     vars[VAR_CHLAYOUT] = inlink->channel_layout;

     vars[VAR_SR] = inlink->sample_rate;

     for (ch = 0; ch < inlink->channels; ch++) {

+        float *rdft_buf = s->kernel_tmp_buf + ch * s->rdft_len;

         double result;

         vars[VAR_CH] = ch;

         vars[VAR_CHID] = av_channel_layout_extract_channel(inlink->channel_layout, ch);

@@ -380,6 +440,9 @@ static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *g

             s->analysis_buf[2*k+1] = 0.0;

         }

+        if (s->dump_buf)

+            memcpy(s->dump_buf, s->analysis_buf, s->analysis_rdft_len * sizeof(*s->analysis_buf));

+

         av_rdft_calc(s->analysis_irdft, s->analysis_buf);

         center = s->fir_len / 2;

@@ -421,35 +484,36 @@ static int generate_kernel(AVFilterContext *ctx, const char *gain, const char *g

                 av_assert0(0);

             }

             s->analysis_buf[k] *= (2.0/s->analysis_rdft_len) * (2.0/s->rdft_len) * win;

+            if (k)

+                s->analysis_buf[s->analysis_rdft_len - k] = s->analysis_buf[k];

         }

-        for (k = 0; k < center - k; k++) {

-            float tmp = s->analysis_buf[k];

-            s->analysis_buf[k] = s->analysis_buf[center - k];

-            s->analysis_buf[center - k] = tmp;

-        }

-

-        for (k = 1; k <= center; k++)

-            s->analysis_buf[center + k] = s->analysis_buf[center - k];

-

-        memset(s->analysis_buf + s->fir_len, 0, (s->rdft_len - s->fir_len) * sizeof(*s->analysis_buf));

-        av_rdft_calc(s->rdft, s->analysis_buf);

+        memset(s->analysis_buf + center + 1, 0, (s->analysis_rdft_len - s->fir_len) * sizeof(*s->analysis_buf));

+        memcpy(rdft_buf, s->analysis_buf + s->analysis_rdft_len - center, center * sizeof(*s->analysis_buf));

+        memcpy(rdft_buf + center, s->analysis_buf, (s->rdft_len - center) * sizeof(*s->analysis_buf));

+        av_rdft_calc(s->rdft, rdft_buf);

         for (k = 0; k < s->rdft_len; k++) {

-            if (isnan(s->analysis_buf[k]) || isinf(s->analysis_buf[k])) {

+            if (isnan(rdft_buf[k]) || isinf(rdft_buf[k])) {

                 av_log(ctx, AV_LOG_ERROR, "filter kernel contains nan or infinity.\n");

                 av_expr_free(gain_expr);

+                if (dump_fp)

+                    fclose(dump_fp);

                 return AVERROR(EINVAL);

             }

         }

-        memcpy(s->kernel_tmp_buf + ch * s->rdft_len, s->analysis_buf, s->rdft_len * sizeof(*s->analysis_buf));

+        if (dump_fp)

+            dump_fir(ctx, dump_fp, ch);

+

         if (!s->multi)

             break;

     }

     memcpy(s->kernel_buf, s->kernel_tmp_buf, (s->multi ? inlink->channels : 1) * s->rdft_len * sizeof(*s->kernel_buf));

     av_expr_free(gain_expr);

+    if (dump_fp)

+        fclose(dump_fp);

     return 0;

 }

@@ -499,6 +563,11 @@ static int config_input(AVFilterLink *inlink)

     if (!(s->analysis_irdft = av_rdft_init(rdft_bits, IDFT_C2R)))

         return AVERROR(ENOMEM);

+    if (s->dumpfile) {

+        s->analysis_rdft = av_rdft_init(rdft_bits, DFT_R2C);

+        s->dump_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->dump_buf));

+    }

+

     s->analysis_buf = av_malloc_array(s->analysis_rdft_len, sizeof(*s->analysis_buf));

     s->kernel_tmp_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->channels : 1), sizeof(*s->kernel_tmp_buf));

     s->kernel_buf = av_malloc_array(s->rdft_len * (s->multi ? inlink->channels : 1), sizeof(*s->kernel_buf));