Child index out of range

[francescofugazzi]

I'm getting this error when running the script

File "E:\instant-ngp\instatest\scripts\agi2nerf.py", line 117, in
p2 = float(calibration[8].text)
IndexError: child index out of range

This is the first part of my camera.xml

<?xml version="1.0" encoding="UTF-8"?>
<document version="1.5.0">
  <chunk label="Chunk 1" enabled="true">
    <sensors next_id="1">
      <sensor id="0" label="unknown" type="frame">
        <resolution width="2160" height="3840"/>
        <property name="layer_index" value="0"/>
        <bands>
          <band label="Red"/>
          <band label="Green"/>
          <band label="Blue"/>
        </bands>
        <data_type>uint8</data_type>
        <calibration type="frame" class="adjusted">
          <resolution width="2160" height="3840"/>
          <f>3183.0178924306147</f>
          <cx>-3.0191925037205407</cx>
          <cy>12.686446764725096</cy>
          <k1>0.063641885377290805</k1>
          <k2>-0.071023441493781495</k2>
          <p1>-0.00066411558984484957</p1>
          <p2>0.00010212604713778139</p2>
        </calibration>
        <covariance>
          <params>f cx cy k1 k2 p1 p2</params>
          <coeffs>4.1246824410526330e-02 1.3776612207456870e-03 -4.2411697298901437e-02 3.9313934678412929e-06 5.1613719565122260e-06 3.7981705742701592e-07 -2.9472749628554441e-06 1.3776612207456870e-03 1.1165396229370850e-01 -6.6260286477075336e-04 -1.0713637960316206e-06 1.1724380451499228e-06 1.3390395933655887e-05 -3.5979429998066325e-07 -4.2411697298901437e-02 -6.6260286477075336e-04 1.5522734082239464e-01 -9.1994667509820920e-06 -2.6694619398151444e-06 -5.7232391216941584e-07 1.2638657326310680e-05 3.9313934678412929e-06 -1.0713637960316206e-06 -9.1994667509820920e-06 1.8435970633465647e-08 -3.2760959388177222e-08 -1.4119818296228413e-12 -5.1504711251021114e-10 5.1613719565122260e-06 1.1724380451499228e-06 -2.6694619398151444e-06 -3.2760959388177222e-08 7.2144288085468655e-08 -4.5890939388192768e-11 -3.3191860613579288e-10 3.7981705742701592e-07 1.3390395933655887e-05 -5.7232391216941584e-07 -1.4119818296228413e-12 -4.5890939388192768e-11 1.8001366517951657e-09 -7.3755948430424168e-11 -2.9472749628554441e-06 -3.5979429998066325e-07 1.2638657326310680e-05 -5.1504711251021114e-10 -3.3191860613579288e-10 -7.3755948430424168e-11 1.3159310546254461e-09</coeffs>
        </covariance>
      </sensor>
    </sensors>
    <components next_id="1" active_id="0">
      <component id="0" label="Component 1">
        <region>
          <center>4.2977201944667870e-01 1.7502952481358156e+00 -5.0967459918202662e+00</center>
          <size>5.7349717330932620e+01 2.9160322952270505e+01 2.2148103713989258e+01</size>
          <R>-4.2651881859495350e-01 -3.1558976947696127e-01 8.4763482395772505e-01 8.9233607291355810e-01 -2.9986785270389826e-01 3.3736568274197981e-01 1.4770927649127080e-01 9.0026794251280085e-01 4.0951141781663902e-01</R>
        </region>
        <partition>
          <camera_ids>0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99</camera_ids>
        </partition>
      </component>
    </components>
    <cameras next_id="100" next_group_id="0">
      <camera id="0" sensor_id="0" component_id="0" label="frame0000">
        <transform>6.6159962375703119e-01 -8.5504944701918273e-02 7.4496633633747211e-01 -2.1656220275301973e+01 -1.5662539868020420e-01 -9.8732166525167608e-01 2.5776225730780811e-02 -4.4206577200835371e+00 7.3331740899341891e-01 -1.3373419067754888e-01 -6.6660388831074180e-01 1.2121529258735372e+01 0 0 0 1</transform>
      </camera>
      <camera id="1" sensor_id="0" component_id="0" label="frame0001">
        <transform>6.8946094121357437e-01 -7.6902871731454520e-02 7.2022882395829457e-01 -2.0820557600907911e+01 -1.4003034579829973e-01 -9.8974074949144719e-01 2.8368134441959958e-02 -4.4201067110215693e+00 7.1065822502557530e-01 -1.2041261194560963e-01 -6.9315632442323927e-01 1.2306224779598960e+01 0 0 0 1</transform>
        <rotation_covariance>9.4240934718966737e-11 -3.3469162716744908e-11 7.2126630848199150e-11 -3.3469162716744914e-11 2.6820691786248343e-10 -2.2300135151498894e-10 7.2126630848199137e-11 -2.2300135151498889e-10 7.4342025435068256e-10</rotation_covariance>
        <location_covariance>4.3269853815255404e-06 -4.7583491511762746e-08 8.8558589241920762e-07 -4.7583491511762746e-08 3.0072993779693618e-08 2.7626120814449582e-08 8.8558589241920762e-07 2.7626120814449582e-08 2.6487925057985070e-07</location_covariance>
      </camera>

[EnricoAhlers]

Hi, sorry for the late answer. Your k3 calibration parameter is missing. It's a radial distortion coefficient for correcting the camera lens distortion. Judging by the resolution of your camera and the missing info about the camera in your XML, I'd guess that you're using digitally created images (e.g. screenshots). You might want to see if you can get that k3 info somewhere. If not, just fill it in with some value. I'm not sure about the impact of that but it's worth trying it out.

[francescofugazzi]

Hi. Thanks for the answer. I managed to solve it by changing the indexes as after writing to you I noticed i was missing the k3 index. hey were frames extracted from a video.

[xrstack]

File "Z:\instant-ngp\scripts\agi2nerf.py", line 117, in <module> p1 = float(calibration[7].text) IndexError: child index out of range

Similar issue as above, except my issue is with a p1 value. I actually have all the various values generated by agisoft (though I'm posing flat video without EXIF as well) -- any idea what's up?

<calibration type="frame" class="adjusted"> <resolution width="2048" height="1152"/> <f>1451.3117496072034</f> <k1>-0.0030940813211349713</k1> <k2>-0.006699597662989859</k2> <k3>0.0082003735322349457</k3> <p1>-0.00093562244250298325</p1> <p2>0.00093194704430539033</p2> </calibration>

[senas8]

Hi im getting an error when running: instant-ngp\data\nerf\example$ python agi2nerf.py --xml_in ./example.xml
" line 5, in
import cv2
ModuleNotFoundError: No module named 'cv2'"