Converting Binary files to ASCII
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Hello everyone,
I am not sure how to convert a Binary file into ASCII file by using matlab. I have seen other similar questions about this in this page but I am not sure about the format of my binary file. It contains points from a disparity map of an image. I have also tried using the tutorials from Matlab, but still I get a wrong result.I attach some binary files so that someone can help
This is the matlab tutorial i was talking about:
A = fread(fileID)
A = fread(fileID,sizeA)
A = fread(fileID,sizeA,precision)
A = fread(fileID,sizeA,precision,skip)
A = fread(fileID,sizeA,precision,skip,machinefmt)
[A,count] = fread(___)
Please, any help would be appreciated.
Thanks in advance
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dpb
2019년 3월 21일
[MM Answer moved to comment...dpb]
This is the only thing the creator said:
Additionally we provide the velodyne point clouds for point-cloud-based methods. To save space, all scans have been stored as Nx4 float matrix into a binary file using the following code:
stream = fopen (dst_file.c_str(),"wb");
fwrite(data,sizeof(float),4*num,stream);
fclose(stream);
Here, data contains 4*num values, where the first 3 values correspond to x,y and z, and the last value is the reflectance information. All scans are stored row-aligned, meaning that the first 4 values correspond to the first measurement. Since each scan might potentially have a different number of points, this must be determined from the file size when reading the file, where 1e6 is a good enough upper bound on the number of values:
// allocate 4 MB buffer (only ~130*4*4 KB are needed)
int32_t num = 1000000;
float *data = (float*)malloc(num*sizeof(float));
// pointers
float *px = data+0;
float *py = data+1;
float *pz = data+2;
float *pr = data+3;
// load point cloud
FILE *stream;
stream = fopen (currFilenameBinary.c_str(),"rb");
num = fread(data,sizeof(float),num,stream)/4;
for (int32_t i=0; i<num; i++) {
point_cloud.points.push_back(tPoint(*px,*py,*pz,*pr));
px+=4; py+=4; pz+=4; pr+=4;
}
fclose(stream);
x,y and y are stored in metric (m) Velodyne coordinates.
답변 (1개)
dpb
2019년 3월 21일
OK, that's all you should need...
fid=fopen('yourfile.ext','r');
data=fread(fid,[inf,4],'single');
fid=fclose(fid);
should return you a Nx4 data array of the x,y,z and reflectance values for each of N measurements.
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