audiovisualizers: add a spacescope element

Add another element that maps left/right channel to x,y coordinates.

1 files changed, 131 insertions, 0 deletions

diff --git a/gst/audiovisualizers/gstspacescope.c b/gst/audiovisualizers/gstspacescope.c
new file mode 100644
index 000000000..b1405e5fe
--- /dev/null
+++ b/gst/audiovisualizers/gstspacescope.c
@@ -0,0 +1,131 @@
+/* GStreamer
+ * Copyright (C) <2011> Stefan Kost <ensonic@users.sf.net>
+ *
+ * gstspacescope.c: simple stereo visualizer
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+/**
+ * SECTION:element-spacescope
+ * @see_also: goom
+ *
+ * Spacescope is a simple audio visualisation element. It maps the left and
+ * right channel to x and y coordinates.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch audiotestsrc ! audioconvert ! spacescope ! ximagesink
+ * ]|
+ * </refsect2>
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstspacescope.h"
+
+static GstStaticPadTemplate gst_space_scope_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_xRGB_HOST_ENDIAN)
+    );
+
+static GstStaticPadTemplate gst_space_scope_sink_template =
+GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_AUDIO_INT_STANDARD_PAD_TEMPLATE_CAPS)
+    );
+
+
+GST_DEBUG_CATEGORY_STATIC (space_scope_debug);
+#define GST_CAT_DEFAULT space_scope_debug
+
+static gboolean gst_space_scope_setup (GstBaseAudioVisualizer * scope);
+static gboolean gst_space_scope_render (GstBaseAudioVisualizer * scope,
+    GstBuffer * audio, GstBuffer * video);
+
+
+GST_BOILERPLATE (GstSpaceScope, gst_space_scope, GstBaseAudioVisualizer,
+    GST_TYPE_BASE_AUDIO_VISUALIZER);
+
+static void
+gst_space_scope_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_set_details_simple (element_class, "Stereo visualizer",
+      "Visualization",
+      "Simple stereo visualizer", "Stefan Kost <ensonic@users.sf.net>");
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_space_scope_src_template));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_space_scope_sink_template));
+}
+
+static void
+gst_space_scope_class_init (GstSpaceScopeClass * g_class)
+{
+  /*GObjectClass *gobject_class = (GObjectClass *) g_class; */
+  GstBaseAudioVisualizerClass *scope_class =
+      (GstBaseAudioVisualizerClass *) g_class;
+
+  scope_class->render = GST_DEBUG_FUNCPTR (gst_space_scope_render);
+}
+
+static void
+gst_space_scope_init (GstSpaceScope * scope, GstSpaceScopeClass * g_class)
+{
+  /* do nothing */
+}
+
+static gboolean
+gst_space_scope_render (GstBaseAudioVisualizer * scope, GstBuffer * audio,
+    GstBuffer * video)
+{
+  guint32 *vdata = (guint32 *) GST_BUFFER_DATA (video);
+  gint16 *adata = (gint16 *) GST_BUFFER_DATA (audio);
+  guint i, s, x, y, off, ox, oy;
+  guint num_samples;
+  gfloat dx, dy;
+  guint w = scope->width;
+
+  /* draw dots 1st channel x, 2nd channel y */
+  num_samples = GST_BUFFER_SIZE (audio) / (scope->channels * sizeof (gint16));
+  dx = scope->width / 65536.0;
+  ox = scope->width / 2;
+  dy = scope->height / 65536.0;
+  oy = scope->height / 2;
+  s = 0;
+  for (i = 0; i < num_samples; i++) {
+    x = (guint) (ox + (gfloat) adata[s++] * dx);
+    y = (guint) (oy + (gfloat) adata[s++] * dy);
+    off = (y * w) + x;
+    vdata[off] = 0x00FFFFFF;
+  }
+  return TRUE;
+}
+
+gboolean
+gst_space_scope_plugin_init (GstPlugin * plugin)
+{
+  GST_DEBUG_CATEGORY_INIT (space_scope_debug, "spacescope", 0, "spacescope");
+
+  return gst_element_register (plugin, "spacescope", GST_RANK_NONE,
+      GST_TYPE_SPACE_SCOPE);
+}