PCA for Compression is somehow tricky!

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Chapter 8

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249

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### Question

Hi Geron, and thank you very much for your great book.
I think the "PCA for Compression" section is somehow tricky. Generally, PCA cannot be used for every image compression, since the original data is required for the decompression phase i.e. the compression/decompression kernel of PCA is dependent to the original data. It can be used for a group of similar images, but I think you'd better mention this issue for the readers. This way, they will know why PCA is not used in general image compression methods like JPEG, ... .