Depth map filenames

[jamesfisher-geo]

Is your feature request related to a problem? Please describe. A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Hello, I am working on an application to measure off RGB images by utilizing their respective depth maps.

I am running a slightly modified build of OpenDroneMap and calling DensifyPointCloud with the following: \"C:\\ODM\\SuperBuild\\install\\bin\\OpenMVS\\DensifyPointCloud\" "scene.mvs" --resolution-level 3 --min-resolution 1024 --max-resolution 8192 --max-threads 16 --number-views-fuse 2 -w "depthmap-directory" -v 4"

This exports the depth maps as .png with the following format depthXXXX.png. Where XXXX is the ID of the image assigned by OpenMVS.

My problem is that I want to work with these depth maps outside of OpenMVS but have no way of connecting the output depth map depthXXXX.png with the associated RGB image (e.g. DJI_1234.jpg).

Describe the solution you'd like

I am wondering if someone could point me in the right direction to modify the code to preserve the original filenames when exporting depth maps to .png.

Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

Alternatively, if someone could provide more information on how image IDs are assigned; and if there is a way to parse .dmap files in Python to extract the source image filename.

Thank you.

[cdcseacave]

the depth-map PNGs are only colored versions of the depth-maps, not the actual depth values you should use the DMAP files instead by using the Interface.h; they also contain the ID of the image it corresponds to

[jamesfisher-geo]

Thank you for the clarification and for the great software package. My updated goal is now to make an executable that will read in a .dmap file and output the raw depth arrays.

It looks like this can be done with the HeaderDepthDataRaw struct and ExportDepthDataRaw function from Interface.h and Depthmap.cpp, respectively.

However, I am a confused on how to call ExportDepthDataRaw as the inputs are (const String& fileName, const String& imageFileName, const IIndexArr& IDs, const cv::Size& imageSize, const KMatrix& K, const RMatrix& R, const CMatrix& C, Depth dMin, Depth dMax, const DepthMap& depthMap, const NormalMap& normalMap, const ConfidenceMap& confMap) Rather than just the .dmap file.

Any guidance here would be much appreciated.

[cdcseacave]

sure, check how it is called in other parts of OpenMVS

[JyothiKalyan]

#include <iostream>
#include <vector>
#include<iostream>
#include<fstream>

using namespace std;

struct HeaderDepthDataRaw {
    enum {
        HAS_DEPTH = (1<<0),
        HAS_NORMAL = (1<<1),
        HAS_CONF = (1<<2),
    };
    uint16_t name; // file type
    uint8_t type; // content type
    uint8_t padding; // reserve
    uint32_t imageWidth, imageHeight; // image resolution
    uint32_t depthWidth, depthHeight; // depth-map resolution
    float dMin, dMax; // depth range for this view

    inline HeaderDepthDataRaw() : name(0), type(0), padding(0) {}
    static uint16_t HeaderDepthDataRawName() { return *reinterpret_cast<const uint16_t*>("DR"); }
};

int main()
{

    FILE *f = fopen("..//floor33//opensfm//undistorted//openmvs//depthmaps//depth0000.dmap", "rb");
    HeaderDepthDataRaw header;
    fread(&header, sizeof(HeaderDepthDataRaw), 1, f);
    uint16_t nFileNameSize;
    fread(&nFileNameSize, sizeof(uint16_t), 1, f);
    std::cout << nFileNameSize << std::endl;
    string imageFileName;
    imageFileName.resize(nFileNameSize);
    fread(&imageFileName[0u], sizeof(char), nFileNameSize, f);
    imageFileName.resize(nFileNameSize);

    size_t found = imageFileName.find("DT_VID");
    string short_name = imageFileName.substr(found, imageFileName.length()-found);
    short_name = short_name.replace(short_name.length()-3,3,"csv");
    std::cout << short_name  << std::endl;

    fread(&imageFileName[0u], sizeof(char), nFileNameSize, f);

    float depthMap[header.depthHeight][header.depthWidth] ;
    fread(depthMap, sizeof(float),header.depthHeight * header.depthWidth , f);

    ofstream fw(short_name, std::ofstream::out);

    if (fw.is_open())
    {
        //store array contents to text file
        for (int i = 0; i < header.depthHeight; i++) {
            for(int k = 0; k< header.depthWidth; k++){
                fw << depthMap[i][k] << ",";
    }
    fw <<  "\n";

  }

}

    fw.close();

}

[trand2k]

#include <iostream>
#include <vector>
#include<iostream>
#include<fstream>

using namespace std;

struct HeaderDepthDataRaw {
    enum {
      HAS_DEPTH = (1<<0),
      HAS_NORMAL = (1<<1),
      HAS_CONF = (1<<2),
    };
    uint16_t name; // file type
    uint8_t type; // content type
    uint8_t padding; // reserve
    uint32_t imageWidth, imageHeight; // image resolution
    uint32_t depthWidth, depthHeight; // depth-map resolution
    float dMin, dMax; // depth range for this view

    inline HeaderDepthDataRaw() : name(0), type(0), padding(0) {}
    static uint16_t HeaderDepthDataRawName() { return *reinterpret_cast<const uint16_t*>("DR"); }
};

int main()
{

    FILE *f = fopen("..//floor33//opensfm//undistorted//openmvs//depthmaps//depth0000.dmap", "rb");
    HeaderDepthDataRaw header;
    fread(&header, sizeof(HeaderDepthDataRaw), 1, f);
    uint16_t nFileNameSize;
    fread(&nFileNameSize, sizeof(uint16_t), 1, f);
    std::cout << nFileNameSize << std::endl;
    string imageFileName;
    imageFileName.resize(nFileNameSize);
    fread(&imageFileName[0u], sizeof(char), nFileNameSize, f);
    imageFileName.resize(nFileNameSize);

    size_t found = imageFileName.find("DT_VID");
    string short_name = imageFileName.substr(found, imageFileName.length()-found);
    short_name = short_name.replace(short_name.length()-3,3,"csv");
    std::cout << short_name  << std::endl;

    fread(&imageFileName[0u], sizeof(char), nFileNameSize, f);

    float depthMap[header.depthHeight][header.depthWidth] ;
    fread(depthMap, sizeof(float),header.depthHeight * header.depthWidth , f);

    ofstream fw(short_name, std::ofstream::out);

    if (fw.is_open())
    {
        //store array contents to text file
        for (int i = 0; i < header.depthHeight; i++) {
            for(int k = 0; k< header.depthWidth; k++){
                fw << depthMap[i][k] << ",";
    }
    fw <<  "\n";

  }

}

    fw.close();

}

hello, I use your code to process raw value of depth map. but my matrix have some value 0 and Nan, what is value mean?

[cdcseacave]

you can just include Interface.h file, and use it.

0 value means invalid depth (does not exist an estimate)

[trand2k]

you can just include Interface.h file, and use it.

0 value means invalid depth (does not exist an estimate)

how about nan and -nan value? . Maximun value is 3e+34 and min is -3.4e+34, this value is distance from camera to pixel in real world? in meter or minimeter?

[cdcseacave]

there should not exist any NaN values, that is an error

[trand2k]

how about 3e+34 and -3.4e+34 value

[cdcseacave]

How about them?

On Wed, 10 May 2023 at 14:08 tradinh @.***> wrote:

how about 3e+34 and -3.4e+34 value

— Reply to this email directly, view it on GitHub https://github.com/cdcseacave/openMVS/issues/805#issuecomment-1541964062, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAVMH3WRKOWMBIJYUBAATATXFNZKTANCNFSM5THUJL5Q . You are receiving this because you commented.Message ID: @.***>

[trand2k]

How about them? … On Wed, 10 May 2023 at 14:08 tradinh @.> wrote: how about 3e+34 and -3.4e+34 value — Reply to this email directly, view it on GitHub <#805 (comment)>, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAVMH3WRKOWMBIJYUBAATATXFNZKTANCNFSM5THUJL5Q . You are receiving this because you commented.Message ID: @.>

depth map have 3e+34 and -3.4e+34 value , i dont think this is a bug, you can read my topic in opendronemap community https://community.opendronemap.org/t/convert-dmap-to-png/15431/9?u=trand2k

[cdcseacave]

it might be a bug, it does not seem realistic we can measure depths of 3e+34 from photos; pls debug or share a small dataset that reproduces the issue

[trand2k]

this is my data i gen from -v 4 option https://drive.google.com/drive/folders/1tY4LM90gRRmpyeVOgoX2vzOIwR1SrOWF?usp=sharing I use this code for reading depth image from .dmap file https://github.com/cdcseacave/openMVS/issues/805#issuecomment-1167057197 Please help me explain this value, thank you so much,

[dev111ce]

this is my data i gen from -v 4 option https://drive.google.com/drive/folders/1tY4LM90gRRmpyeVOgoX2vzOIwR1SrOWF?usp=sharing I use this code for reading depth image from .dmap file https://github.com/cdcseacave/openMVS/issues/805#issuecomment-1167057197 Please help me explain this value, thank you so much,

How to generate a depth map with openmvs' -v 4 option, I can't find it