klv: add klv library, klvinject and klvinspect elements

Create as a separate library until gst-plugins-base MR124 is merged into tag
2020-02-06 13:33:56 -05:00
parent 1502c7fa9c
commit ec20592591
14 changed files with 533 additions and 15 deletions
--- a/gst/klv/gstklvinspect.c
+++ b/gst/klv/gstklvinspect.c
@@ -0,0 +1,124 @@
+/* GStreamer
+ * Copyright (C) 2016 William Manley <will@williammanley.net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Suite 500,
+ * Boston, MA 02110-1335, USA.
+ */
+/**
+ * SECTION:element-gstklvinspect
+ *
+ * The klvinspect element inspects KLV metadata on passing buffers.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch -v fakesrc ! klvinspect ! fakesink
+ * ]|
+ * FIXME Describe what the pipeline does.
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <gst/base/gstbasetransform.h>
+#include "gstklvinspect.h"
+#include "klv.h"
+
+GST_DEBUG_CATEGORY_STATIC (gst_klvinspect_debug_category);
+#define GST_CAT_DEFAULT gst_klvinspect_debug_category
+
+/* prototypes */
+static GstFlowReturn gst_klvinspect_transform_ip (GstBaseTransform * trans,
+    GstBuffer * buf);
+
+enum
+{
+  PROP_0
+};
+
+/* pad templates */
+
+#define SRC_CAPS "ANY"
+#define SINK_CAPS "ANY"
+
+
+/* class initialization */
+
+G_DEFINE_TYPE_WITH_CODE (GstKlvInspect, gst_klvinspect, GST_TYPE_BASE_TRANSFORM,
+    GST_DEBUG_CATEGORY_INIT (gst_klvinspect_debug_category, "klvinspect", 0,
+        "debug category for klvinspect element"));
+
+static void
+gst_klvinspect_class_init (GstKlvInspectClass * klass)
+{
+  GstBaseTransformClass *base_transform_class =
+      GST_BASE_TRANSFORM_CLASS (klass);
+
+  /* Setting up pads and setting metadata should be moved to
+     base_class_init if you intend to subclass this class. */
+  gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
+      gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
+          gst_caps_from_string (SRC_CAPS)));
+  gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
+      gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
+          gst_caps_from_string (SINK_CAPS)));
+
+  gst_element_class_set_static_metadata (GST_ELEMENT_CLASS (klass),
+      "Inspect KLV", "Filter", "Inspect KLV metadata",
+      "Joshua M. Doe <oss@nvl.army.mil>");
+
+  base_transform_class->transform_ip =
+      GST_DEBUG_FUNCPTR (gst_klvinspect_transform_ip);
+
+  base_transform_class->passthrough_on_same_caps = TRUE;
+  base_transform_class->transform_ip_on_passthrough = TRUE;
+}
+
+static void
+gst_klvinspect_init (GstKlvInspect * filt)
+{
+}
+
+static void
+gst_klvinspect_dispose (GstKlvInspect * filt)
+{
+}
+
+static GstFlowReturn
+gst_klvinspect_transform_ip (GstBaseTransform * trans, GstBuffer * buf)
+{
+  GstKlvInspect *filt = GST_KLVINSPECT (trans);
+  GstKLVMeta *klv_meta;
+  gpointer iter = NULL;
+  gint n_klv_meta_found = 0;
+
+  while ((klv_meta = (GstKLVMeta *) gst_buffer_iterate_meta_filtered (buf,
+              &iter, GST_KLV_META_API_TYPE))) {
+    gsize klv_size;
+    const guint8 *klv_data;
+    klv_data = gst_klv_meta_get_data (klv_meta, &klv_size);
+    if (klv_data) {
+      GST_MEMDUMP_OBJECT (filt, "KLV data", klv_data, (guint) klv_size);
+      ++n_klv_meta_found;
+    }
+  }
+
+  GST_LOG_OBJECT (filt, "Found %d KLV meta", n_klv_meta_found);
+
+  return GST_FLOW_OK;
+}