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@ -100,14 +100,14 @@ function Document:discardChange()
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end
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-- calculate partial digest of the document
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-- since only PDF documents could be modified by koreader by appending data
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-- since only PDF documents could be modified by KOReader by appending data
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-- at the end of the files when highlighting, we use a non-even sampling
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-- algorithm which samples with larger weight at file head and much smaller
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-- weight at file tail, thus reduces the probability that appended data may change
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-- the digest value.
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-- Note that if PDF file size is around 1024, 4096, 16384, 65536, 262144
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-- 1048576, 4194304, 16777216, 67108864, 268435456 or 1073741824, appending data
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-- by highlighting in koreader may change the digest value.
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-- by highlighting in KOReader may change the digest value.
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function Document:fastDigest()
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local md5 = require("ffi/MD5")
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local lshift = bit.lshift
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