Matlab中的量化数据

Question

假设我在Matlab中有一些图，如下所示：

x = linspace(0,10,10000);
input= sin(x);

我想把数据量化到一定数量的位。(我从技术上认识到，MATLAB量化了所有的图形。)我试过以下几种方法：

bits = 7;
output =floor(2^bits*input)/2^bits

但是，只有当输入介于0和1之间时，这才有效。我应该做什么？

Answer 1

基于方法#1 bsxfun的“内插式”方案

x = linspace(min(input),max(input),2^bits) %// Setup the quantizied levels 
                                         %// ranging from min to max of the input data
[~,ind1] = min(abs(bsxfun(@minus,input,x.'))) %//' Find the indices of the 
                                              %// levels nearest to the input data
output = x(ind1) %// Get the quantized values

另外，不要使用与内置MATLAB函数名相同的变量名称，在本例中是input。

方法#2 interp1 -

x = linspace(min(input),max(input),2^bits) %// Setup the quantizied levels 
                                         %// ranging from min to max of the input data
output = interp1(x,x,input,'nearest') %// Get quantized values with 1-D interpolation
                                      %// to the nearest quantized levels

例子-

input [Input data] =
    0.8017    1.0533   -0.7489   -0.9363   -1.2691    0.4980    2.7891
bits [No. of bits used for quantization ] =
     2
x [These are 2^bits quantized levels ranging from min to max of input] =
   -1.2691    0.0836    1.4364    2.7891
output [Input data is brought to the nearest quantized levels taken from x] =
    1.4364    1.4364   -1.2691   -1.2691   -1.2691    0.0836    2.7891