34 lines
752 B
Plaintext
34 lines
752 B
Plaintext
using Printf
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mutable struct VLQ
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quant::Vector{UInt8}
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end
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function VLQ(n::T) where T <: Integer
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quant = UInt8.(digits(n, 128))
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@inbounds for i in 2:length(quant) quant[i] |= 0x80 end
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VLQ(reverse(quant))
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end
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import Base.UInt64
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function Base.UInt64(vlq::VLQ)
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quant = reverse(vlq.quant)
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n = shift!(quant)
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p = one(UInt64)
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for i in quant
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p *= 0x80
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n += p * ( i & 0x7f)
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end
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return n
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end
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const test = [0x00200000, 0x001fffff, 0x00000000, 0x0000007f,
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0x00000080, 0x00002000, 0x00003fff, 0x00004000,
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0x08000000, 0x0fffffff]
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for i in test
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vlq = VLQ(i)
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j = UInt(vlq)
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@printf "0x%-8x => [%-25s] => 0x%x\n" i join(("0x" * hex(r, 2) for r in vlq.quant), ", ") j
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end
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