sharpetronics/zstd
1
0
Fork 0
mirror of https://github.com/facebook/zstd.git synced 2025-10-04 00:02:33 -04:00
Code Issues Projects Releases Wiki Activity

added ascending order example

Browse Source
This commit is contained in:
Yann Collet 2024-10-09 01:06:24 -07:00
parent 3b343dcfb1
commit 3e7c66acd1
1 changed files with 7 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
doc/zstd_compression_format.md
View File

@ -1400,7 +1400,7 @@ It is possible to transform weights into `Number_of_Bits`, using this formula:
```
Number_of_Bits = (Weight>0) ? Max_Number_of_Bits + 1 - Weight : 0
```
In order to determine which prefix is assigned to each Symbol,
In order to determine which prefix code is assigned to each Symbol,
Symbols are first sorted by `Weight`, then by natural sequential order.
Symbols with a `Weight` of zero are removed.
Then, starting from lowest `Weight` (hence highest `Number_of_Bits`),
@ -1416,11 +1416,12 @@ Let's assume the following list of weights has been decoded:
Sorted by weight and then natural sequential order,
it gives the following prefix codes distribution:
| Literal | D | E | F | C | B | A |
| ---------------- | --- | ---- | ---- | --- | --- | --- |
| `Weight` | 0 | 1 | 1 | 2 | 3 | 4 |
| `Number_of_Bits` | 0 | 4 | 4 | 3 | 2 | 1 |
| prefix code | N/A | 0000 | 0001 | 001 | 01 | 1 |
| Literal | D | E | F | C | B | A |
| ---------------- | --- | ---- | ---- | ---- | ---- | ---- |
| `Weight` | 0 | 1 | 1 | 2 | 3 | 4 |
| `Number_of_Bits` | 0 | 4 | 4 | 3 | 2 | 1 |
| prefix code | N/A | 0000 | 0001 | 001 | 01 | 1 |
| ascending order | N/A | 0000 | 0001 | 001x | 01xx | 1xxx |
### Huffman-coded Streams