audio-converter: make some optimized functions

Make an optimized function that just calls the resampler when possible.
Optimize the resampler transform_size function a little.

gst-libs/gst/audio/audio-converter.c

@@ -513,7 +513,7 @@ do_resample (AudioChain * chain, gpointer user_data)
   gsize in_frames, out_frames;
 
   in = audio_chain_get_samples (chain->prev, &in_frames);
-  out_frames = convert->out_samples;
+  out_frames = convert->out_frames;
   out = (chain->allow_ip ? in : audio_chain_alloc_samples (chain, out_frames));
 
   GST_LOG ("resample %p %p,%" G_GSIZE_FORMAT " %" G_GSIZE_FORMAT, in,
@@ -845,7 +845,6 @@ converter_passthrough (GstAudioConverter * convert,
     for (i = 0; i < chain->blocks; i++)
       gst_audio_format_fill_silence (convert->in.finfo, out[i], samples);
   }
-
   return TRUE;
 }
 
@@ -880,6 +879,17 @@ converter_generic (GstAudioConverter * convert,
   return TRUE;
 }
 
+static gboolean
+converter_resample (GstAudioConverter * convert,
+    GstAudioConverterFlags flags, gpointer in[], gsize in_frames,
+    gpointer out[], gsize out_frames)
+{
+  gst_audio_resampler_resample (convert->resampler, in, in_frames, out,
+      out_frames);
+
+  return TRUE;
+}
+
 /**
  * gst_audio_converter_new: (skip)
  * @flags: extra #GstAudioConverterFlags
@@ -942,10 +952,15 @@ gst_audio_converter_new (GstAudioConverterFlags flags, GstAudioInfo * in_info,
 
   /* optimize */
   if (out_info->finfo->format == in_info->finfo->format
-      && convert->mix_passthrough && convert->resampler == NULL) {
-    GST_INFO
-        ("same formats, no resampler and passthrough mixing -> passthrough");
-    convert->convert = converter_passthrough;
+      && convert->mix_passthrough) {
+    if (convert->resampler == NULL) {
+      GST_INFO
+          ("same formats, no resampler and passthrough mixing -> passthrough");
+      convert->convert = converter_passthrough;
+    } else {
+      GST_INFO ("same formats, and passthrough mixing -> only resampling");
+      convert->convert = converter_resample;
+    }
   } else {
     GST_INFO ("do full conversion");
     convert->convert = converter_generic;

gst-libs/gst/audio/audio-resampler.c

@@ -77,7 +77,6 @@ struct _GstAudioResampler
 
   guint blocks;
   guint inc;
-  gboolean filling;
   gint samp_inc;
   gint samp_frac;
   gint samp_index;
@@ -970,7 +969,6 @@ gst_audio_resampler_update (GstAudioResampler * resampler,
   resampler_calculate_taps (resampler);
   resampler_dump (resampler);
 
-  resampler->filling = TRUE;
   resampler->samp_index = 0;
   resampler->samp_phase = 0;
   resampler->samples_avail = resampler->n_taps / 2 - 1;

gst/audioresample/gstaudioresample.c

@@ -431,61 +431,32 @@ gst_audio_resample_reset_state (GstAudioResample * resample)
 {
 }
 
-static gint
-_gcd (gint a, gint b)
-{
-  while (b != 0) {
-    int temp = a;
-
-    a = b;
-    b = temp % b;
-  }
-
-  return ABS (a);
-}
-
 static gboolean
 gst_audio_resample_transform_size (GstBaseTransform * base,
     GstPadDirection direction, GstCaps * caps, gsize size, GstCaps * othercaps,
     gsize * othersize)
 {
+  GstAudioResample *resample = GST_AUDIO_RESAMPLE (base);
   gboolean ret = TRUE;
-  GstAudioInfo in, out;
-  guint32 ratio_den, ratio_num;
-  gint inrate, outrate, gcd;
   gint bpf;
 
   GST_LOG_OBJECT (base, "asked to transform size %" G_GSIZE_FORMAT
       " in direction %s", size, direction == GST_PAD_SINK ? "SINK" : "SRC");
 
-  /* Get sample width -> bytes_per_samp, channels, inrate, outrate */
-  ret = gst_audio_info_from_caps (&in, caps);
-  ret &= gst_audio_info_from_caps (&out, othercaps);
-  if (G_UNLIKELY (!ret)) {
-    GST_ERROR_OBJECT (base, "Wrong caps");
-    return FALSE;
-  }
   /* Number of samples in either buffer is size / (width*channels) ->
    * calculate the factor */
-  bpf = GST_AUDIO_INFO_BPF (&in);
-  inrate = GST_AUDIO_INFO_RATE (&in);
-  outrate = GST_AUDIO_INFO_RATE (&out);
+  bpf = GST_AUDIO_INFO_BPF (&resample->in);
 
   /* Convert source buffer size to samples */
   size /= bpf;
 
-  /* Simplify the conversion ratio factors */
-  gcd = _gcd (inrate, outrate);
-  ratio_num = inrate / gcd;
-  ratio_den = outrate / gcd;
-
   if (direction == GST_PAD_SINK) {
-    /* asked to convert size of an incoming buffer. Round up the output size */
-    *othersize = gst_util_uint64_scale_int_ceil (size, ratio_den, ratio_num);
+    /* asked to convert size of an incoming buffer */
+    *othersize = gst_audio_converter_get_out_frames (resample->converter, size);
     *othersize *= bpf;
   } else {
-    /* asked to convert size of an outgoing buffer. Round down the input size */
-    *othersize = gst_util_uint64_scale_int (size, ratio_num, ratio_den);
+    /* asked to convert size of an outgoing buffer */
+    *othersize = gst_audio_converter_get_in_frames (resample->converter, size);
     *othersize *= bpf;
   }
 
@@ -810,9 +781,6 @@ gst_audio_resample_process (GstAudioResample * resample, GstBuffer * inbuf,
         gpointer in[1], out[1];
         GstAudioConverterFlags flags;
 
-        out_len =
-            gst_audio_converter_get_out_frames (resample->converter, in_len);
-
         flags = 0;
         if (inbuf_writable)
           flags |= GST_AUDIO_CONVERTER_FLAG_IN_WRITABLE;
@@ -853,7 +821,6 @@ gst_audio_resample_process (GstAudioResample * resample, GstBuffer * inbuf,
   gst_buffer_unmap (outbuf, &out_map);
 
   outsize = out_len * resample->in.bpf;
-  gst_buffer_resize (outbuf, 0, outsize);
 
   GST_LOG_OBJECT (resample,
       "Converted to buffer of %" G_GUINT32_FORMAT