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来源：花匠小妙招时间：2026-02-05 02:06

1,【H264/AVC 句法和语义详解】(五)：Exp-Golomb指数哥伦布编码（理论篇)

https://blog.csdn.net/u011399342/article/details/80472399

公式如下:
其中leadingZeroBits为1前面，0的个数。所以在解码的时候，如果遇到描述子为ue(v)，则可以先数0的个数，数到1为止，其中0的个数即为leadingZeroBits。而公式中的read_bits( leadingZeroBits )，则为从中间1开始，往后顺序数leadingZeroBits个比特位,将这几个比特位所表示的数值返回。

leadingZeroBits = −1

for (b = 0; !b; leadingZeroBits++)

b = read_bits(1)

codeNum = 2^(leadingZeroBits) − 1 + read_bits(leadingZeroBits)

长度=2*leadingZeroBits+1

二进制比特串长度 0阶指数哥伦布解码值

1001 1 0

001 1001 5 5

01 1010 3 2

010 3 1

000 1011 7 10

0001 001 7 8

cpp

运行

利用上述公式，就可以计算出codeNum的值。

x0~x4可表示0或者1

2,Exponential-Golomb decoding http://guoh.org/lifelog/2013/10/exp-golomb-coding/

对于11110001 01100001 01100010 01100010进行哥伦布解码

过程就是读取1位，在这里结果是1，所以会跳出循环，但是leadingZeroBits++还是会执行，所以leadingZeroBits为0，后面read_bits也不会读取数据了。
codeNum = 2^0 – 1 + 0 = 0
也就是说编码为1的属性实际值为0
seq_parameter_set_id = 0 // Exp-Golomb解11110001中的第一个字码1

3,Se(v)

if the syntax element is coded as se(v), the value of the syntax element is derived by invoking the mapping process for signed Exp-Golomb codes as specified in ue(v) with codeNum as the input.

4,Exponential-Golomb coding

https://en.wikipedia.org/wiki/Exponential-Golomb_coding

0阶哥伦布:

To code a number x ≥ 1:

Let

be the highest power of 2 it contains, so

.Write out N zero bits, thenAppend the binary form of (x+1), the binary form of (x+1) is an (N+1)-bit binary number.

An equivalent way to express the same process: To encode any nonnegative integer x using the exp-Golomb code:

Write down x+1 in binaryCount the bits written, subtract one, and write that number of starting zero bits preceding the previous bit string.

k阶哥伦布:

To encode larger numbers in fewer bits (at the expense of using more bits to encode smaller numbers), this can be generalized using a nonnegative integer parameter k. To encode a nonnegative integer x in an order-k exp-Golomb code: