Check failed: max_num_elems > 0 (0 vs. 0)

Describe the bug I’m trying to execute the preprocessing command on the nerfstudio documentation:

ns-process-data video --data {data_path} --output-dir {output_path} --no_gpu

Using no_gpu flag as I do not have a display. Running these on a EC2 instance. AMD64, 20.04 Ubuntu with CUDA 11.6

But the following error appears:

[12:53:19] 🎉 Done converting video to images.                                                       process_data.py:178
[12:53:47] 🎉 Done downscaling images.                                                               process_data.py:322
           🎉 Done extracting COLMAP features.                                                       process_data.py:363
──────────────────────────────────────────────  💀 💀 💀 ERROR 💀 💀 💀  ───────────────────────────────────────────────
Error running command: colmap vocab_tree_matcher --database_path /home/ubuntu/Datasets/Processed/colmap/database.db 
--SiftMatching.use_gpu 0 --VocabTreeMatching.vocab_tree_path /home/ubuntu/.local/share/nerfstudio/vocab_tree.fbow
────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
F20221025 12:53:48.190236 134291 cache.h:132] Check failed: max_num_elems > 0 (0 vs. 0) 
*** Check failure stack trace: ***
    @     0x55602e3a7a00  google::LogMessage::SendToLog()
    @     0x55602e3a3f46  google::LogMessage::Flush()
    @     0x55602e3a819f  google::LogMessageFatal::~LogMessageFatal()
    @     0x55602db72bbd  colmap::LRUCache<>::LRUCache()
    @     0x55602db61dd7  colmap::FeatureMatcherCache::Setup()
    @     0x55602db6de96  colmap::VocabTreeFeatureMatcher::Run()
    @     0x55602dcc7ad1  colmap::Thread::RunFunc()
    @     0x7f0c8a74cde4  (unknown)
    @     0x7f0c8a86a609  start_thread
    @     0x7f0c8a544133  clone
    @              (nil)  (unknown)
Aborted (core dumped)

Reproduce Installed colmap using the vcpkg succesfully. Then, run the command written above to preprocess custom data.

*Expected behavior I expected colmap to run the preprocessing correctly.

Thanks in advance!

[tancik]

Yep, try giving this video a go - https://drive.google.com/file/d/19zEm-CpOjpVObFzGqrxou5ndBjb_fAui/view?usp=sharing

[corbt]

I ran into this issue yesterday as well when running a working nerfstudio Docker image on a new host with a different GPU.

For future readers, it’s worth clarifying that this issue is a generic problem that means that COLMAP wasn’t able to place any images. The actual reason COLMAP failed can vary. You can sometimes get more information by manually running the COLMAP feature extractor from the command line manually and checking the output for errors. In my case I ran colmap feature_extractor --database_path test.db --image_path ./images --ImageReader.single_camera 1 --ImageReader.camera_model OPENCV --SiftExtraction.use_gpu 0, and saw that COLMAP wasn’t able to access my GPU for some reason.