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zstd_compression_format.md: "Little-endian" instead of "Little endian"

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inikep 2016-07-25 12:47:02 +02:00
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zstd_compression_format.md
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@ -106,7 +106,7 @@ The structure of a single Zstandard frame is following:
__`Magic_Number`__ __`Magic_Number`__
4 Bytes, Little endian format. 4 Bytes, Little-endian format.
Value : 0xFD2FB527 Value : 0xFD2FB527
__`Frame_Header`__ __`Frame_Header`__
@ -178,7 +178,7 @@ The `Value` can be converted to `Field_Size` that is number of bytes used by `Fr
| ---------- | --- | --- | --- | --- | | ---------- | --- | --- | --- | --- |
|`Field_Size`| 0-1 | 2 | 4 | 8 | |`Field_Size`| 0-1 | 2 | 4 | 8 |
The meaning of `Value` equal 0 depends on `Single_Segment_flag` : The meaning of `Value` equal to `0` depends on `Single_Segment_flag` :
it either means `0` (size not provided) _if_ the `Window_Descriptor` byte is present, it either means `0` (size not provided) _if_ the `Window_Descriptor` byte is present,
or `1` (frame content size <= 255 bytes) otherwise. or `1` (frame content size <= 255 bytes) otherwise.
@ -297,20 +297,20 @@ the following ranges are reserved for future use and should not be used :
### `Frame_Content_Size` ### `Frame_Content_Size`
This is the original (uncompressed) size. This is the original (uncompressed) size. This information is optional.
This information is optional, and only present if `Single_Segment_flag` is set. The `Field_Size` is provided according to value of `Frame_Content_Size_flag`.
Content size is provided using 1, 2, 4 or 8 bytes according to `Frame_Content_Size_flag`. The `Field_Size` can be equal to 0 (not present), 1, 2, 4 or 8 bytes.
Format is Little endian. Format is Little-endian.
| Field Size | Range | | `Field_Size` | Range |
| ---------- | ---------- | | ------------ | ---------- |
| 1 | 0 - 255 | | 1 | 0 - 255 |
| 2 | 256 - 65791| | 2 | 256 - 65791|
| 4 | 0 - 2^32-1 | | 4 | 0 - 2^32-1 |
| 8 | 0 - 2^64-1 | | 8 | 0 - 2^64-1 |
When field size is 1, 4 or 8 bytes, the value is read directly. When `Field_Size` is 1, 4 or 8 bytes, the value is read directly.
When field size is 2, _the offset of 256 is added_. When `Field_Size` is 2, _the offset of 256 is added_.
It's allowed to represent a small size (for example `18`) using any compatible variant. It's allowed to represent a small size (for example `18`) using any compatible variant.
In order to preserve decoder from unreasonable memory requirement, In order to preserve decoder from unreasonable memory requirement,
@ -389,7 +389,7 @@ Skippable frames defined in this specification are compatible with [LZ4] ones.
__`Magic_Number`__ __`Magic_Number`__
4 Bytes, Little endian format. 4 Bytes, Little-endian format.
Value : 0x184D2A5X, which means any value from 0x184D2A50 to 0x184D2A5F. Value : 0x184D2A5X, which means any value from 0x184D2A50 to 0x184D2A5F.
All 16 values are valid to identify a skippable frame. All 16 values are valid to identify a skippable frame.
@ -397,7 +397,7 @@ __`Frame_Size`__
This is the size, in bytes, of the following `User_Data` This is the size, in bytes, of the following `User_Data`
(without including the magic number nor the size field itself). (without including the magic number nor the size field itself).
This field is represented using 4 Bytes, Little endian format, unsigned 32-bits. This field is represented using 4 Bytes, Little-endian format, unsigned 32-bits.
This means `User_Data` can’t be bigger than (2^32-1) bytes. This means `User_Data` can’t be bigger than (2^32-1) bytes.
__`User_Data`__ __`User_Data`__
@ -662,7 +662,7 @@ Regenerated size of each stream can be calculated by `(totalSize+3)/4`,
except for last one, which can be up to 3 bytes smaller, to reach `totalSize`. except for last one, which can be up to 3 bytes smaller, to reach `totalSize`.
Compressed size is provided explicitly : in the 4-streams variant, Compressed size is provided explicitly : in the 4-streams variant,
bitstreams are preceded by 3 unsigned Little Endian 16-bits values. bitstreams are preceded by 3 unsigned Little-Endian 16-bits values.
Each value represents the compressed size of one stream, in order. Each value represents the compressed size of one stream, in order.
The last stream size is deducted from total compressed size The last stream size is deducted from total compressed size
and from previously decoded stream sizes : and from previously decoded stream sizes :
@ -1127,9 +1127,9 @@ __Pre-requisites__ : a dictionary has a known length,
| Header | DictID | Stats | Content | | Header | DictID | Stats | Content |
| ------ | ------ | ----- | ------- | | ------ | ------ | ----- | ------- |
__Header__ : 4 bytes ID, value 0xEC30A437, Little Endian format __Header__ : 4 bytes ID, value 0xEC30A437, Little-Endian format
__Dict_ID__ : 4 bytes, stored in Little Endian format. __Dict_ID__ : 4 bytes, stored in Little-Endian format.
DictID can be any value, except 0 (which means no DictID). DictID can be any value, except 0 (which means no DictID).
It's used by decoders to check if they use the correct dictionary. It's used by decoders to check if they use the correct dictionary.
_Reserved ranges :_ _Reserved ranges :_
@ -1146,7 +1146,7 @@ __Stats__ : Entropy tables, following the same format as a [compressed blocks].
Huffman tables for literals, FSE table for offset, Huffman tables for literals, FSE table for offset,
FSE table for matchLenth, and FSE table for litLength. FSE table for matchLenth, and FSE table for litLength.
It's finally followed by 3 offset values, populating recent offsets, It's finally followed by 3 offset values, populating recent offsets,
stored in order, 4-bytes little endian each, for a total of 12 bytes. stored in order, 4-bytes little-endian each, for a total of 12 bytes.
__Content__ : Where the actual dictionary content is. __Content__ : Where the actual dictionary content is.
Content size depends on Dictionary size. Content size depends on Dictionary size.