baseparse: Add missing annotations

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1392>

subprojects/gstreamer/libs/gst/base/gstbaseparse.c

@@ -1058,7 +1058,7 @@ gst_base_parse_parse_frame (GstBaseParse * parse, GstBaseParseFrame * frame)
  * @src_format: #GstFormat describing the source format.
  * @src_value: Source value to be converted.
  * @dest_format: #GstFormat defining the converted format.
- * @dest_value: Pointer where the conversion result will be put.
+ * @dest_value: (out): Pointer where the conversion result will be put.
  *
  * Converts using configured "convert" vmethod in #GstBaseParse class.
  *

subprojects/gstreamer/libs/gst/base/gstbaseparse.h

@@ -242,6 +242,21 @@ struct _GstBaseParseClass {
   gboolean      (*set_sink_caps)      (GstBaseParse * parse,
                                        GstCaps      * caps);
 
+  /**
+   * GstBaseParseClass::handle_frame:
+   * @skipsize: (out):
+   *
+   * Parses the input data into valid frames as defined by subclass
+   * which should be passed to gst_base_parse_finish_frame().
+   * The frame's input buffer is guaranteed writable,
+   * whereas the input frame ownership is held by caller
+   * (so subclass should make a copy if it needs to hang on).
+   * Input buffer (data) is provided by baseclass with as much
+   * metadata set as possible by baseclass according to upstream
+   * information and/or subclass settings,
+   * though subclass may still set buffer timestamp and duration
+   * if desired.
+   */
   GstFlowReturn (*handle_frame)       (GstBaseParse      * parse,
                                        GstBaseParseFrame * frame,
                                        gint              * skipsize);