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Small fixes to zstd specification 

Update to keep in sync with the RFC.
dev
Nick Terrell 2018-07-10 15:07:36 -07:00
parent 14a92e90fe
commit c1a7defee1
1 changed files with 4 additions and 4 deletions
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doc/zstd_compression_format.md
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@ -488,20 +488,20 @@ For values spanning several bytes, convention is __little-endian__.
__`Size_Format` for `Raw_Literals_Block` and `RLE_Literals_Block`__ :
`Size_Format` uses 1 _or_ 2 bits.
Its value is : `Size_Format = (Header[0]>>2) & 3`
Its value is : `Size_Format = (Literals_Section_Header[0]>>2) & 3`
- `Size_Format` == 00 or 10 : `Size_Format` uses 1 bit.
`Regenerated_Size` uses 5 bits (0-31).
`Literals_Section_Header` uses 1 byte.
`Regenerated_Size = Header[0]>>3`
`Regenerated_Size = Literals_Section_Header[0]>>3`
- `Size_Format` == 01 : `Size_Format` uses 2 bits.
`Regenerated_Size` uses 12 bits (0-4095).
`Literals_Section_Header` uses 2 bytes.
`Regenerated_Size = (Header[0]>>4) + (Header[1]<<4)`
`Regenerated_Size = (Literals_Section_Header[0]>>4) + (Literals_Section_Header[1]<<4)`
- `Size_Format` == 11 : `Size_Format` uses 2 bits.
`Regenerated_Size` uses 20 bits (0-1048575).
`Literals_Section_Header` uses 3 bytes.
`Regenerated_Size = (Header[0]>>4) + (Header[1]<<4) + (Header[2]<<12)`
`Regenerated_Size = (Literals_Section_Header[0]>>4) + (Literals_Section_Header[1]<<4) + (Literals_Section_Header[2]<<12)`
Only Stream1 is present for these cases.
Note : it's allowed to represent a short value (for example `13`)