45
the key frames. e frame numbers for Bellour’s key frames and frame set boundaries were selected
using visual comparison between the photographs from Bellour’s article and the extracted frames.
Frame sets were composed of all the frames between successively identied key frames and tagged
using Bellour’s numbering convention. Bellour grouped frame sets into higherlevel groups. e
frame sets were arranged into higher level groups using Bellour’s description.
2.4.10 RESULTS
Due to the dierences in precision between Bellour’s analysis and the structural analysis, we be-
lieved that visual analysis would be the most appropriate option for the task at hand. Bellour’s
analysis began with shot number 3 of the segment and continued to shot 84. Bellour includes two
groups of shots that have little bearing on his analysis of the sequence: Melanie’s acquisition and
boarding of the boat (3–12) and Melanie’s arrival at the dock following her trip and the gull strike
(84a–84f ). ese sets do not play into Bellour’s analysis and appear to function only to demarcate
the segment within the larger document—the entire lm of e Birds.
Detection of key frames and frame sets. Figure 2.9 shows the absolute value of the dier-
ence between the Gini value of a particular frame of the Bodega Bay sequence of e Birds and
the previous frame. e mean dierence between frames for all frames in the sequence is 0.003826,
which is represented on the graph by the green (lower) horizontal line. e mean dierence be-
tween frames identied as key frames by Bellour was 0.075678. e dierence values fall into a
bimodal distribution. e dierence values of key frames and the proceeding frame were an order of
magnitude higher than the dierence values between frames that were not identied as key frames.
Figure 2.10 shows the Gini coecients for each frame broken down into individual frame sets as
identied by Bellour. Within shots, the Gini coecients remain stable for most shots and trend in
a linear manner. Notable exceptions to this pattern include the group of frame sets that make up
Bellour’s “hinge” sequence (25–43); the gull strike (77); and Melanie’s arrival at the dock following
the gull strike (84a–84f ).
Analysis of frame sets. Figure 2.10 shows the Gini coecients of each frame of the segment
broken down by shot number, presenting the ow of the color distributions across the time of the
lm sequence. We might construct a tact map by overlayering indicators for some of the key el-
ements mapped by the data in Figure 2.10, as in Figure 2.11. Once Melanie is actually underway
on her trip to the Brenner house, we have almost uninterrupted alternation. We are presented with
Melanie in the boat, then the Brenner house as she sees it—Bellour’s shots 15–22. en we are
presented with Melanie paddling the boat and seeing the dock—23–24; then walking on the dock
and seeing the barn—25–31. at is, shots 15–31 present Melanie, what she sees, Melanie, what
she sees, and so on. e latter portion is more distinct in the graph, though the entire sequence of
shots clearly shows alternation.
2.4 STORY FOUR: FUNCTIONAL ONTOLOGY