Load metadata from video files and expose via RNA

The MovieSequence and MovieClip classes now have a metadata() function
that exposes the `IDProperty *` holding the video metadata.

Part of: https://developer.blender.org/D2273

Reviewed by: @campbellbarton

3 files changed, 85 insertions, 1 deletions

diff --git a/source/blender/makesrna/intern/rna_ID.c b/source/blender/makesrna/intern/rna_ID.c
index a9e34247cbd..bc2c26c2b2b 100644
--- a/source/blender/makesrna/intern/rna_ID.c
+++ b/source/blender/makesrna/intern/rna_ID.c
@@ -754,6 +754,14 @@ static PointerRNA rna_IDPreview_get(PointerRNA *ptr)
 	return rna_pointer_inherit_refine(ptr, &RNA_ImagePreview, prv_img);
 }
 
+static IDProperty *rna_IDPropertyWrapPtr_idprops(PointerRNA *ptr, bool UNUSED(create))
+{
+	if (ptr == NULL) {
+		return NULL;
+	}
+	return ptr->data;
+}
+
 #else
 
 static void rna_def_ID_properties(BlenderRNA *brna)
@@ -1105,6 +1113,20 @@ static void rna_def_library(BlenderRNA *brna)
 	RNA_def_function_flag(func, FUNC_USE_REPORTS | FUNC_USE_CONTEXT);
 	RNA_def_function_ui_description(func, "Reload this library and all its linked data-blocks");
 }
+
+/**
+ * \attention This is separate from the above. It allows for RNA functions to
+ * return an IDProperty *. See MovieClip.metadata for a usage example.
+ **/
+static void rna_def_idproperty_wrap_ptr(BlenderRNA *brna)
+{
+	StructRNA *srna;
+
+	srna = RNA_def_struct(brna, "IDPropertyWrapPtr", NULL);
+	RNA_def_struct_idprops_func(srna, "rna_IDPropertyWrapPtr_idprops");
+	RNA_def_struct_flag(srna, STRUCT_NO_DATABLOCK_IDPROPERTIES);
+}
+
 void RNA_def_ID(BlenderRNA *brna)
 {
 	StructRNA *srna;
@@ -1122,6 +1144,7 @@ void RNA_def_ID(BlenderRNA *brna)
 	rna_def_ID_properties(brna);
 	rna_def_ID_materials(brna);
 	rna_def_library(brna);
+	rna_def_idproperty_wrap_ptr(brna);
 }
 
 #endif
diff --git a/source/blender/makesrna/intern/rna_movieclip.c b/source/blender/makesrna/intern/rna_movieclip.c
index fb743f5236d..d63f3fe76f8 100644
--- a/source/blender/makesrna/intern/rna_movieclip.c
+++ b/source/blender/makesrna/intern/rna_movieclip.c
@@ -33,6 +33,7 @@
 #include "DNA_movieclip_types.h"
 #include "DNA_scene_types.h"
 
+#include "RNA_access.h"
 #include "RNA_define.h"
 
 #include "rna_internal.h"
@@ -44,6 +45,7 @@
 
 #include "IMB_imbuf_types.h"
 #include "IMB_imbuf.h"
+#include "IMB_metadata.h"
 
 #ifdef RNA_RUNTIME
 
@@ -103,6 +105,22 @@ static void rna_MovieClipUser_proxy_render_settings_update(Main *UNUSED(bmain),
 	}
 }
 
+static PointerRNA rna_MovieClip_metadata_get(MovieClip *clip)
+{
+	if (clip == NULL || clip->anim == NULL) {
+		return PointerRNA_NULL;
+	}
+
+	IDProperty *metadata = IMB_anim_load_metadata(clip->anim);
+	if (metadata == NULL) {
+		return PointerRNA_NULL;
+	}
+
+	PointerRNA ptr;
+	RNA_pointer_create(NULL, &RNA_IDPropertyWrapPtr, metadata, &ptr);
+	return ptr;
+}
+
 #else
 
 static void rna_def_movieclip_proxy(BlenderRNA *brna)
@@ -257,6 +275,8 @@ static void rna_def_movieclip(BlenderRNA *brna)
 {
 	StructRNA *srna;
 	PropertyRNA *prop;
+	FunctionRNA *func;
+	PropertyRNA *parm;
 
 	static const EnumPropertyItem clip_source_items[] = {
 		{MCLIP_SRC_SEQUENCE, "SEQUENCE", 0, "Image Sequence", "Multiple image files, as a sequence"},
@@ -348,6 +368,14 @@ static void rna_def_movieclip(BlenderRNA *brna)
 	RNA_def_property_struct_type(prop, "ColorManagedInputColorspaceSettings");
 	RNA_def_property_ui_text(prop, "Color Space Settings", "Input color space settings");
 
+	/* metadata */
+	func = RNA_def_function(srna, "metadata", "rna_MovieClip_metadata_get");
+	RNA_def_function_ui_description(func, "Retrieve metadata of the movie file");
+	/* return type */
+	parm = RNA_def_pointer(func, "metadata", "IDPropertyWrapPtr", "", "Dict-like object containing the metadata");
+	RNA_def_parameter_flags(parm, 0, PARM_RNAPTR);
+	RNA_def_function_return(func, parm);
+
 	rna_def_animdata_common(srna);
 }
 
diff --git a/source/blender/makesrna/intern/rna_sequencer.c b/source/blender/makesrna/intern/rna_sequencer.c
index 81c05433e66..33621af69af 100644
--- a/source/blender/makesrna/intern/rna_sequencer.c
+++ b/source/blender/makesrna/intern/rna_sequencer.c
@@ -41,6 +41,8 @@
 #include "BKE_sequencer.h"
 #include "BKE_sound.h"
 
+#include "IMB_metadata.h"
+
 #include "MEM_guardedalloc.h"
 
 #include "RNA_access.h"
@@ -587,6 +589,27 @@ static IDProperty *rna_Sequence_idprops(PointerRNA *ptr, bool create)
 	return seq->prop;
 }
 
+static PointerRNA rna_MovieSequence_metadata_get(Sequence *seq)
+{
+	if (seq == NULL || seq->anims.first == NULL) {
+		return PointerRNA_NULL;
+	}
+
+	StripAnim *sanim = seq->anims.first;
+	if (sanim->anim == NULL) {
+		return PointerRNA_NULL;
+	}
+
+	IDProperty *metadata = IMB_anim_load_metadata(sanim->anim);
+	if (metadata == NULL) {
+		return PointerRNA_NULL;
+	}
+
+	PointerRNA ptr;
+	RNA_pointer_create(NULL, &RNA_IDPropertyWrapPtr, metadata, &ptr);
+	return ptr;
+}
+
 static PointerRNA rna_SequenceEditor_meta_stack_get(CollectionPropertyIterator *iter)
 {
 	ListBaseIterator *internal = &iter->internal.listbase;
@@ -1963,7 +1986,9 @@ static void rna_def_movie(BlenderRNA *brna)
 {
 	StructRNA *srna;
 	PropertyRNA *prop;
-	
+	FunctionRNA *func;
+	PropertyRNA *parm;
+
 	srna = RNA_def_struct(brna, "MovieSequence", "Sequence");
 	RNA_def_struct_ui_text(srna, "Movie Sequence", "Sequence strip to load a video");
 	RNA_def_struct_sdna(srna, "Sequence");
@@ -1995,6 +2020,14 @@ static void rna_def_movie(BlenderRNA *brna)
 	                              "rna_Sequence_filepath_set");
 	RNA_def_property_update(prop, NC_SCENE | ND_SEQUENCER, "rna_Sequence_filepath_update");
 
+	/* metadata */
+	func = RNA_def_function(srna, "metadata", "rna_MovieSequence_metadata_get");
+	RNA_def_function_ui_description(func, "Retrieve metadata of the movie file");
+	/* return type */
+	parm = RNA_def_pointer(func, "metadata", "IDPropertyWrapPtr", "", "Dict-like object containing the metadata");
+	RNA_def_parameter_flags(parm, 0, PARM_RNAPTR);
+	RNA_def_function_return(func, parm);
+
 	/* multiview */
 	prop = RNA_def_property(srna, "use_multiview", PROP_BOOLEAN, PROP_NONE);
 	RNA_def_property_boolean_sdna(prop, NULL, "flag", SEQ_USE_VIEWS);