31 lines
1.4 KiB
Markdown
31 lines
1.4 KiB
Markdown
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# Demo 2: Comparing two images
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The [comparison demo](demos/compare.py) outputs the predicted similarity
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score of two faces by computing the squared L2 distance between
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their representations.
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A lower score indicates two faces are more likely of the same person.
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Since the representations are on the unit hypersphere, the
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scores range from 0 (the same picture) to 4.0.
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The following distances between images of John Lennon and
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Eric Clapton were generated with
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`./demos/compare.py images/examples/{lennon*,clapton*}`.
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| Lennon 1 | Lennon 2 | Clapton 1 | Clapton 2 |
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|---|---|---|---|
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| <img src='../../images/examples/lennon-1.jpg' width='200px'></img> | <img src='../../images/examples/lennon-2.jpg' width='200px'></img> | <img src='../../images/examples/clapton-1.jpg' width='200px'></img> | <img src='../../images/examples/clapton-2.jpg' width='200px'></img> |
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The following table shows that a distance threshold of `0.5` would
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distinguish these two people.
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In practice, further experimentation should be done on the distance threshold.
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On our LFW experiments, the mean threshold across multiple
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experiments is 0.71 ± 0.027,
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see [accuracies.txt](evaluation/lfw.nn4.v1.epoch-177/accuracies.txt).
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| Image 1 | Image 2 | Distance |
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| Lennon 1 | Lennon 2 | 0.310 |
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| Lennon 1 | Clapton 1 | 1.241 |
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| Lennon 1 | Clapton 2 | 1.056 |
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| Lennon 2 | Clapton 1 | 1.386 |
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| Lennon 2 | Clapton 2 | 1.073 |
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| Clapton 1 | Clapton 2 | 0.259 |
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