+/**
+ * Allocates and initializes a mediacontrol_RGBPicture object.
+ *
+ * @param i_width: picture width
+ * @param i_height: picture width
+ * @param i_chroma: picture chroma
+ * @param l_date: picture timestamp
+ * @param p_data: pointer to the data. The data will be directly used, not copied.
+ * @param i_datasize: data size in bytes
+ *
+ * @return the new object, or NULL on error.
+ */