plugin: Add clapper GStreamer plugin

Add new GStreamer plugin that consists of multiple elements for Clapper video player. The main difference is that unlike the old one, this does not operate using `GtkGLArea` anymore, but processes and displays `GdkTextures` directly through `GtkPicture` widget. Also this one is installed like any other GStreamer plugin, thus can be used via `gst-launch-1.0` binary or even used by other GTK4 apps if they wish to integrate it. This commit adds new video sink that uses a new kind of memory as input, called `ClapperGdkMemory`. With it comes a simple dedicated memory allocator, buffer pool and a `clapperimport` element that converts system mapped memory frames into `GdkTextures` that are later passed in our `ClapperGdkMemory` for the sink to display.
2025-08-29 23:32:04 +02:00 · 2022-03-05 09:16:10 +01:00
parent f771e0320c
commit 0061e133f9
21 changed files with 2976 additions and 37 deletions
--- a/lib/gst/plugin/gstclapperbaseimport.c
+++ b/lib/gst/plugin/gstclapperbaseimport.c
@@ -0,0 +1,374 @@
+/*
+ * Copyright (C) 2022 Rafał Dzięgiel <rafostar.github@gmail.com>
+ *
+ * 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 St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstclapperbaseimport.h"
+#include "gstclappergdkmemory.h"
+#include "gstclappergdkbufferpool.h"
+
+#define GST_CAT_DEFAULT gst_clapper_base_import_debug
+GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
+
+#define parent_class gst_clapper_base_import_parent_class
+G_DEFINE_TYPE (GstClapperBaseImport, gst_clapper_base_import, GST_TYPE_BASE_TRANSFORM);
+
+static void
+gst_clapper_base_import_init (GstClapperBaseImport *self)
+{
+  g_mutex_init (&self->lock);
+
+  gst_video_info_init (&self->in_info);
+  gst_video_info_init (&self->out_info);
+}
+
+static void
+gst_clapper_base_import_finalize (GObject *object)
+{
+  GstClapperBaseImport *self = GST_CLAPPER_BASE_IMPORT_CAST (object);
+
+  GST_TRACE ("Finalize");
+  g_mutex_clear (&self->lock);
+
+  GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (object));
+}
+
+static GstStateChangeReturn
+gst_clapper_base_import_change_state (GstElement *element, GstStateChange transition)
+{
+  GST_DEBUG_OBJECT (element, "Changing state: %s => %s",
+      gst_element_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),
+      gst_element_state_get_name (GST_STATE_TRANSITION_NEXT (transition)));
+
+  return GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+}
+
+static gboolean
+gst_clapper_base_import_start (GstBaseTransform *bt)
+{
+  GST_INFO_OBJECT (bt, "Start");
+
+  return TRUE;
+}
+
+static gboolean
+gst_clapper_base_import_stop (GstBaseTransform *bt)
+{
+  GST_INFO_OBJECT (bt, "Stop");
+
+  return TRUE;
+}
+
+static GstCaps *
+gst_clapper_base_import_transform_caps (GstBaseTransform *bt,
+    GstPadDirection direction, GstCaps *caps, GstCaps *filter)
+{
+  GstCaps *result, *tmp;
+
+  tmp = (direction == GST_PAD_SINK)
+      ? gst_pad_get_pad_template_caps (GST_BASE_TRANSFORM_SRC_PAD (bt))
+      : gst_pad_get_pad_template_caps (GST_BASE_TRANSFORM_SINK_PAD (bt));
+
+  if (filter) {
+    GST_DEBUG ("Intersecting with filter caps: %" GST_PTR_FORMAT, filter);
+    result = gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);
+    gst_caps_unref (tmp);
+  } else {
+    result = tmp;
+  }
+  GST_DEBUG ("Returning %s caps: %" GST_PTR_FORMAT,
+      (direction == GST_PAD_SINK) ? "src" : "sink", result);
+
+  return result;
+}
+
+static gboolean
+_structure_filter_cb (GQuark field_id, GValue *value,
+    G_GNUC_UNUSED gpointer user_data)
+{
+  const gchar *str = g_quark_to_string (field_id);
+
+  if (!strcmp (str, "format")
+      || !strcmp (str, "width")
+      || !strcmp (str, "height")
+      || !strcmp (str, "pixel-aspect-ratio")
+      || !strcmp (str, "framerate"))
+    return TRUE;
+
+  return FALSE;
+}
+
+static GstCaps *
+gst_clapper_base_import_fixate_caps (GstBaseTransform *bt,
+    GstPadDirection direction, GstCaps *caps, GstCaps *othercaps)
+{
+  GstCaps *fixated;
+
+  fixated = (!gst_caps_is_any (caps))
+      ? gst_caps_fixate (gst_caps_ref (caps))
+      : gst_caps_copy (caps);
+
+  if (direction == GST_PAD_SINK) {
+    guint i, n = gst_caps_get_size (fixated);
+
+    for (i = 0; i < n; i++) {
+      GstCapsFeatures *features;
+      GstStructure *structure;
+      gboolean had_overlay_comp;
+
+      features = gst_caps_get_features (fixated, i);
+      had_overlay_comp = gst_caps_features_contains (features,
+          GST_CAPS_FEATURE_META_GST_VIDEO_OVERLAY_COMPOSITION);
+
+      features = gst_caps_features_new (GST_CAPS_FEATURE_CLAPPER_GDK_MEMORY, NULL);
+      if (had_overlay_comp)
+        gst_caps_features_add (features, GST_CAPS_FEATURE_META_GST_VIDEO_OVERLAY_COMPOSITION);
+
+      gst_caps_set_features (fixated, i, features);
+
+      /* Remove fields that do not apply to our memory */
+      if ((structure = gst_caps_get_structure (fixated, i))) {
+        gst_structure_filter_and_map_in_place (structure,
+            (GstStructureFilterMapFunc) _structure_filter_cb, NULL);
+      }
+    }
+  }
+  GST_DEBUG ("Fixated %s caps: %" GST_PTR_FORMAT,
+      (direction == GST_PAD_SRC) ? "sink" : "src", fixated);
+
+  return fixated;
+}
+
+static gboolean
+gst_clapper_base_import_set_caps (GstBaseTransform *bt,
+    GstCaps *incaps, GstCaps *outcaps)
+{
+  GstClapperBaseImport *self = GST_CLAPPER_BASE_IMPORT_CAST (bt);
+  gboolean has_sink_info, has_src_info;
+
+  if ((has_sink_info = gst_video_info_from_caps (&self->in_info, incaps)))
+    GST_INFO_OBJECT (self, "Set sink caps: %" GST_PTR_FORMAT, incaps);
+  if ((has_src_info = gst_video_info_from_caps (&self->out_info, outcaps)))
+    GST_INFO_OBJECT (self, "Set src caps: %" GST_PTR_FORMAT, outcaps);
+
+  return (has_sink_info && has_src_info);
+}
+
+static gboolean
+gst_clapper_base_import_import_propose_allocation (GstBaseTransform *bt,
+    GstQuery *decide_query, GstQuery *query)
+{
+  GstClapperBaseImport *self = GST_CLAPPER_BASE_IMPORT_CAST (bt);
+  GstClapperBaseImportClass *bi_class = GST_CLAPPER_BASE_IMPORT_GET_CLASS (self);
+  GstBufferPool *pool = NULL;
+  GstCaps *caps;
+  GstVideoInfo info;
+  guint size;
+  gboolean need_pool;
+
+  if (!GST_BASE_TRANSFORM_CLASS (parent_class)->propose_allocation (bt,
+      decide_query, query))
+    return FALSE;
+
+  /* Passthrough, nothing to do */
+  if (!decide_query)
+    return TRUE;
+
+  gst_query_parse_allocation (query, &caps, &need_pool);
+
+  if (!caps) {
+    GST_DEBUG_OBJECT (self, "No caps specified");
+    return FALSE;
+  }
+
+  if (!gst_video_info_from_caps (&info, caps)) {
+    GST_DEBUG_OBJECT (self, "Invalid caps specified");
+    return FALSE;
+  }
+
+  /* Normal size of a frame */
+  size = GST_VIDEO_INFO_SIZE (&info);
+
+  if (need_pool) {
+    GstStructure *config = NULL;
+
+    GST_DEBUG_OBJECT (self, "Need to create upstream pool");
+    pool = bi_class->create_upstream_pool (self, &config);
+
+    if (pool) {
+      /* If we did not get config, use default one */
+      if (!config)
+        config = gst_buffer_pool_get_config (pool);
+
+      gst_buffer_pool_config_set_params (config, caps, size, 2, 0);
+
+      if (!gst_buffer_pool_set_config (pool, config)) {
+        gst_object_unref (pool);
+
+        GST_DEBUG_OBJECT (self, "Failed to set config");
+        return FALSE;
+      }
+    } else if (config) {
+      GST_WARNING_OBJECT (self, "Got pool config without a pool to apply it!");
+      gst_structure_free (config);
+    }
+  }
+
+  gst_query_add_allocation_pool (query, pool, size, 2, 0);
+  if (pool)
+    gst_object_unref (pool);
+
+  gst_query_add_allocation_meta (query,
+      GST_VIDEO_OVERLAY_COMPOSITION_META_API_TYPE, NULL);
+  gst_query_add_allocation_meta (query, GST_VIDEO_META_API_TYPE, NULL);
+
+  return TRUE;
+}
+
+static gboolean
+gst_clapper_base_import_decide_allocation (GstBaseTransform *bt, GstQuery *query)
+{
+  GstClapperBaseImport *self = GST_CLAPPER_BASE_IMPORT_CAST (bt);
+  GstBufferPool *pool = NULL;
+  GstCaps *caps;
+  GstVideoInfo info;
+  guint size = 0, min = 0, max = 0;
+  gboolean update_pool, need_pool = TRUE;
+
+  gst_query_parse_allocation (query, &caps, NULL);
+
+  if (!caps) {
+    GST_DEBUG_OBJECT (self, "No caps specified");
+    return FALSE;
+  }
+
+  if (!gst_video_info_from_caps (&info, caps)) {
+    GST_DEBUG_OBJECT (self, "Invalid caps specified");
+    return FALSE;
+  }
+
+  if ((update_pool = gst_query_get_n_allocation_pools (query) > 0)) {
+    gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
+    if (pool) {
+      if ((need_pool = !GST_IS_CLAPPER_GDK_BUFFER_POOL (pool)))
+        gst_clear_object (&pool);
+    }
+  } else {
+    size = GST_VIDEO_INFO_SIZE (&info);
+  }
+
+  if (need_pool) {
+    GstStructure *config;
+
+    GST_DEBUG_OBJECT (self, "Creating new downstream pool");
+
+    pool = gst_clapper_gdk_buffer_pool_new ();
+    config = gst_buffer_pool_get_config (pool);
+
+    gst_buffer_pool_config_add_option (config, GST_BUFFER_POOL_OPTION_VIDEO_META);
+    gst_buffer_pool_config_set_params (config, caps, size, min, max);
+
+    if (!gst_buffer_pool_set_config (pool, config)) {
+      gst_object_unref (pool);
+
+      GST_DEBUG_OBJECT (self, "Failed to set config");
+      return FALSE;
+    }
+  }
+
+  if (update_pool)
+    gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
+  else
+    gst_query_add_allocation_pool (query, pool, size, min, max);
+
+  if (pool)
+    gst_object_unref (pool);
+
+  return GST_BASE_TRANSFORM_CLASS (parent_class)->decide_allocation (bt, query);
+}
+
+static GstBufferPool *
+gst_clapper_base_import_create_upstream_pool (GstClapperBaseImport *self, GstStructure **config)
+{
+  GST_FIXME_OBJECT (self, "Need to create upstream buffer pool");
+
+  return NULL;
+}
+
+static void
+gst_clapper_base_import_class_init (GstClapperBaseImportClass *klass)
+{
+  GObjectClass *gobject_class = (GObjectClass *) klass;
+  GstElementClass *gstelement_class = (GstElementClass *) klass;
+  GstBaseTransformClass *gstbasetransform_class = (GstBaseTransformClass *) klass;
+  GstClapperBaseImportClass *bi_class = (GstClapperBaseImportClass *) klass;
+
+  GST_DEBUG_CATEGORY_INIT (GST_CAT_DEFAULT, "clapperbaseimport", 0,
+      "Clapper Base Import");
+
+  gobject_class->finalize = gst_clapper_base_import_finalize;
+
+  gstelement_class->change_state = gst_clapper_base_import_change_state;
+
+  gstbasetransform_class->passthrough_on_same_caps = TRUE;
+  gstbasetransform_class->transform_ip_on_passthrough = FALSE;
+  gstbasetransform_class->start = gst_clapper_base_import_start;
+  gstbasetransform_class->stop = gst_clapper_base_import_stop;
+  gstbasetransform_class->transform_caps = gst_clapper_base_import_transform_caps;
+  gstbasetransform_class->fixate_caps = gst_clapper_base_import_fixate_caps;
+  gstbasetransform_class->set_caps = gst_clapper_base_import_set_caps;
+  gstbasetransform_class->propose_allocation = gst_clapper_base_import_import_propose_allocation;
+  gstbasetransform_class->decide_allocation = gst_clapper_base_import_decide_allocation;
+
+  bi_class->create_upstream_pool = gst_clapper_base_import_create_upstream_pool;
+}
+
+/*
+ * Maps input video frame and output memory from in/out buffers
+ * using flags passed to this method.
+ *
+ * Remember to unmap both using `gst_video_frame_unmap` and
+ * `gst_memory_unmap` when done with the data.
+ */
+gboolean
+gst_clapper_base_import_map_buffers (GstClapperBaseImport *self,
+    GstBuffer *in_buf, GstBuffer *out_buf, GstMapFlags in_flags, GstMapFlags out_flags,
+    GstVideoFrame *frame, GstMapInfo *info, GstMemory **mem)
+{
+  GST_LOG_OBJECT (self, "Transforming from %" GST_PTR_FORMAT
+      " into %" GST_PTR_FORMAT, in_buf, out_buf);
+
+  if (G_UNLIKELY (!gst_video_frame_map (frame, &self->in_info, in_buf, in_flags))) {
+    GST_ERROR_OBJECT (self, "Could not map input buffer for reading");
+    return FALSE;
+  }
+
+  *mem = gst_buffer_peek_memory (out_buf, 0);
+
+  if (G_UNLIKELY (!gst_memory_map (*mem, info, out_flags))) {
+    GST_ERROR_OBJECT (self, "Could not map output memory for writing");
+    gst_video_frame_unmap (frame);
+
+    return FALSE;
+  }
+
+  return TRUE;
+}