MLX90640 紅外熱成像儀測(cè)溫模塊開(kāi)發(fā)筆記（四）

MLX90640 紅外熱成像儀測(cè)溫模塊開(kāi)發(fā)筆記（四）損壞和不良像素的處理 

如前“開(kāi)發(fā)筆記（一）”所說(shuō)，MLX90640 可能存在不超過(guò) 4 個(gè)像素的損壞或者不良像素，在溫度計(jì)算過(guò)程完成后，這些不良像素點(diǎn)會(huì)得到錯(cuò)誤的溫度數(shù)據(jù)，對(duì)于處理這些不良數(shù)據(jù) MLX 也給出了推薦方法和具體的函數(shù)。（其實(shí)就是找相鄰的正常的溫度數(shù)據(jù)取平均來(lái)代替不良數(shù)據(jù)） 

前面開(kāi)發(fā)筆記（一）的內(nèi)容中所說(shuō)的 API 庫(kù)，里面缺少了對(duì)不良像素點(diǎn)的處理函數(shù)，在這里補(bǔ)上。 

int CheckAdjacentPixels(uint16_t pix1, uint16_t pix2)

{

int pixPosDif;

pixPosDif = pix1 - pix2;

if(pixPosDif > -34 && pixPosDif < -30)

{

return -6;

}

if(pixPosDif > -2 && pixPosDif < 2)

{

return -6;

}

if(pixPosDif > 30 && pixPosDif < 34)

{

return -6;

}

return 0;

}

float GetMedian(float *values, int n)

{

float temp;

for(int i=0; i<n-1; i++)

{

for(int j=i+1; j<n; j++)

{

if(values[j] < values[i])

{

temp = values[i]; values[i] = values[j]; values[j] = temp;

}

}

if(n%2==0)

{

return ((values[n/2] + values[n/2 - 1]) / 2.0);

}

else

{

}

return values[n/2];

}

int IsPixelBad(uint16_t pixel,paramsMLX90640 *params)

{

for(int i=0; i<5; i++)

{

if(pixel == params->outlierPixels[i] || pixel == params->brokenPixels[i])

{

return 1;

}

}

return 0;

}

void MLX90640_BadPixelsCorrection(uint16_t *pixels, float *to, int mode, paramsMLX90640

*params)

{

float ap[4]; uint8_t pix; uint8_t line; uint8_t column;

pix = 0;

while(pixels[pix] != 0xFFFF)

{

line = pixels[pix]>>5;

column = pixels[pix] - (line<<5);

if(mode == 1)

{

if(line == 0)

{

if(column == 0)

{

to[pixels[pix]] = to[33];

}

else if(column == 31)

{

}

else

{

}

}

to[pixels[pix]] = to[62];

to[pixels[pix]] = (to[pixels[pix]+31] + to[pixels[pix]+33])/2.0;

else if(line == 23)

{

if(column == 0)

{

to[pixels[pix]] = to[705];

}

else if(column == 31)

{

}

else

{

}

}

to[pixels[pix]] = to[734];

to[pixels[pix]] = (to[pixels[pix]-33] + to[pixels[pix]-31])/2.0;

else if(column == 0)

{

to[pixels[pix]] = (to[pixels[pix]-31] + to[pixels[pix]+33])/2.0;

}

else if(column == 31)

{

}

else

{

to[pixels[pix]] = (to[pixels[pix]-33] + to[pixels[pix]+31])/2.0;

ap[0] = to[pixels[pix]-33];

ap[1] = to[pixels[pix]-31]; ap[2] = to[pixels[pix]+31]; ap[3] = to[pixels[pix]+33];

to[pixels[pix]] = GetMedian(ap,4);

}

else

{

}

if(column == 0)

{

to[pixels[pix]] = to[pixels[pix]+1];

}

else if(column == 1 || column == 30)

{

to[pixels[pix]] = (to[pixels[pix]-1]+to[pixels[pix]+1])/2.0;

}

else if(column == 31)

{

}

else

{

0)

to[pixels[pix]] = to[pixels[pix]-1];

if(IsPixelBad(pixels[pix]-2,params) == 0 && IsPixelBad(pixels[pix]+2,params) ==

{

ap[0] = to[pixels[pix]+1] - to[pixels[pix]+2]; ap[1] = to[pixels[pix]-1] - to[pixels[pix]-2];

if(fabs(ap[0]) > fabs(ap[1]))

{

}

else

{

}

else

{

}

to[pixels[pix]] = to[pixels[pix]-1] + ap[1];

to[pixels[pix]] = to[pixels[pix]+1] + ap[0];

to[pixels[pix]] = (to[pixels[pix]-1]+to[pixels[pix]+1])/2.0;

}

}

}

pix = pix + 1;

}

}

用法很簡(jiǎn)單，在開(kāi)發(fā)筆記（三）MLX90640_CalculateTo(Frame, MLXPars, 0.95, Tr, Temp);之后添加兩行即可。如下（斜體是添加的內(nèi)容）：

……

MLX90640_CalculateTo(Frame, MLXPars, 0.95, Tr, Temp); MLX90640_BadPixelsCorrection(MLXPars.brokenPixels, Temp, 1, MLXPars); MLX90640_BadPixelsCorrection(MLXPars.outlierPixels, Temp, 1, MLXPars);

……

/*

經(jīng)過(guò)上面的處理后，Temp 中的損壞和不良像素點(diǎn)已經(jīng)處理，Temp 數(shù)組中是處理完成后的

768 個(gè)溫度值。

*/

成果展示。