How to determine the code in the 13th polyline coding segment of the law a

Hello, I teach you a new way. First, list the table as shown in the image. Then according to the positive and negative of your sampling pulse value, judge the polarity code, the positive value is 1, the negative value is 0, and secondly, according to which interval the sampling pulse value falls in, and then get the paragraph code, for example, in the figure, the pulse value falls in the range of 512-1024, which is in the seventh paragraph, so the paragraph code is 110.

Finally, the pulse value is subtracted by the smallest value of the interval, divided by the corresponding quantization interval, and the decimal point is removed, and then converted into a BCD code, and finally the encoder is obtained.

's output codeset.

First, the polarity code is determined according to the positive and negative values of the sampling pulse value. A positive value is 1 and a negative value is 0. Then, according to which interval the sampled pulse value falls in, the paragraph code is obtained.

For example, if the pulse value falls in the range of 512-1024, it is in the seventh segment, so the paragraph code is 110. Finally, the pulse value is subtracted from the smallest value of the interval, divided by the corresponding quantization interval, and the decimal point is removed, and then converted into BCD code, and finally the output code set of the encoder is obtained.

The first step is to determine the first symbol code according to the polarity of the sample value.

The second step is to determine which of the 8 paragraphs the value is located in according to the sample value, that is, to determine the paragraph code.

The third step is to determine which interval (a total of 16 intervals) in the paragraph determined in the previous step according to the size of the sample value, that is, to determine the intra-paragraph code.

Requirements: Memorize the beginning of the paragraph code in the 13-line code, as well as the quantization interval for each paragraph.

Example: The 13-fold line A law is used to compile the positive code of the base mu, and the normalized 1 is divided into 2048 quantitative units. Set the sample value of the input and output signal x to +1270, and find the code group.

The sampling pulse value x 1270 is known, and the 8-digit codes of the code set are c1c2c3c4c5c6c7c8

Because x>0, c1 1

And because x>1024, and x

The larger the number of Liqiao digits encoded by the A-law 13 polyline encoder, the smaller the error and the lower the channel utilization.

Extension: The principle of the A-law 13 polyline encoder is that in the positive 8 segments and the negative 8 segments, the positive 1 and 2 segments and the negative macro scrambler 1 and 2 segments have the same slope and are combined into one section. Therefore, the original 16-segment line becomes a 13-segment line, so it is also called the A-law 13-segment line.

The 13-bit linear coding is a PCM encoding rule that corresponds to the A-law mask recommended by the ITU standard.

A-law is a compression and decompression algorithm for pulse coding defined by the ITU-T (ITU Telecommunication Standards Bureau) CCITT. Most countries in the world use the A-law compression algorithm. In the United States, the MU law algorithm is used for pulse coding.

If the quantizer overload voltage is 1, which is equivalent to normalizing the input signal, then the logarithmic compression of the a-law I define as when 0 <=x <=1 a, f(x)=(ax) (1+lna) f(x)=(1+lna) when 1 a <=x <=1, f(x)=(1+lnax) (1+lna).

According to the positive and negative of your sampling pulse value, judge the polarity code, the positive value is 1, the negative value is 0, secondly, according to which interval the sampling pulse value falls in, and then get the paragraph code, for example, in the figure, the pulse value falls in the range of 512-1024, which is in the seventh paragraph, so the paragraph code is 110. Finally, the pulse value is subtracted from the minimum value before the front of the range, divided by the corresponding quantization interval, and after the decimal point is removed, Biji Pure converts it into BCD code, and finally obtains the output code set of the encoder. I hope I can help you.

A-law is a compression and decompression algorithm for pulse coding defined by the ITU-T (ITU Telecommunication Standards Bureau) CCITT. Most countries in the world use the A-law compression algorithm. In the United States, the MU law algorithm is used for pulse coding.

If the quantizer overload voltage is 1, which is equivalent to normalizing the input signal, then the logarithmic compression of the a-law I define as when 0 <=x <=1 a, f(x)=(ax) (1+lna) f(x)=(1+lna) when 1 a <=x <=1, f(x)=(1+lnax) (1+lna).

The law of a is to approximate the logarithm with a 13-fold line.

The compliment characteristic is achieved with a polyline, which is different from both a uniformly quantified straight line and a smooth curve with logarithmic companding characteristic. Although in general the use of polylines for compression expansion is non-uniform quantification, it has both non-uniform (different polylines have different slopes) quantification and uniform quantification (within a small range of the same polyline). There are two commonly used digital companding techniques, one is the 13-fold line A-law compand, which is similar to the A-law companding characteristics of A=.

The other is a 15-fold linear compand, whose characteristics are approximately =255. The following will mainly introduce the 13-fold line A-law companding technology, referred to as the 13-fold line method. With regard to the 15-fold line law compaction, readers are invited to read the relevant literature.