4.6.3 Embedded components

The data in table 5 shows that Office documents are rich in component data, with 18.19% of Word documents and 46.38% of PowerPoint documents having at least one embedded component. Furthermore, the data shows a high diversity of component types, with Word documents having the highest diversity.

Table 6 shows the popularity and average size of component types for Word, PowerPoint, and Excel documents. For all three applications, image components are either the first or second most popular type. Additionally, the average size of image components is among the largest of all types. This evidence further suggests that efforts toward reducing file size should focus on image types.

We observed that for all three applications, the average number of embedded components and the average size of the components increases as documents get bigger. This trend is similar to the one shown in figure 9 and 10 for images, and is consistent with the findings of section 4.2, where the contribution of embedded components to the document size grows significantly as document size increases.

 

Table 5: Embedded components statistics. The table shows the percentage of documents that have at least one embedded components, the number of different component types, the average number of components in a document, and the average and standard deviation of the size of embedded components.

	Application
Statistic	Word	PowerPoint	Excel
% with components	18.19	46.38	1.42
number of component types	55	11	8
average number of components	6.71	9.18	9.05
average component size (KB)	37.62	18.51	26.01
stdev (KB)	141.78	109.33	133.37

 

Table 6: Average size and popularity of component types in Word, PowerPoint, and Excel documents.

	Application
	Word		PowerPoint		Excel
Component	Avg. Size (KB)	% of Occur.	Avg. Size (KB)	% of Occur.	Avg. Size (KB)	% of Occur.
Equation	0.74	51.12	0.81	1.82
Other Image			28.68	38.80	4.99	5.00
Word Picture	80.68	14.81	1.31	0.15	2066.83	1.00
Clip Art	10.38	8.93	5.00	41.12	2.56	15.00
Excel Sheet	153.46	8.53	53.18	5.27
OLE Link	23.80	3.90
Paint Brush	315.75	1.71			17.91	42.00
MS Draw	7.28	1.35
PowerPoint	41.74	0.96
Word			23.28	8.01	28.17	32.00
Graph			3.26	3.86
Sound			3.35	0.02
Other	97.52	8.68	8.72	0.94	2.39	5.00