# How to use voxl-logger to sample hires camera?

Source: https://forum.modalai.com/topic/633/how-to-use-voxl-logger-to-sample-hires-camera
Category: Development Drones (https://forum.modalai.com/category/44/development-drones)
Tags: m500
Posted: 2022-01-04 17:16:38 UTC by Matthew Howlett
Replies: 2 · Views: 1237

## Matthew Howlett · 2022-01-04 17:16:38 UTC

Hello,
I am able use the voxl-logger for both the stereo and tracking camera, but for some unknown reason I cannot sample the hires camera. What am I missing here? 

I can provide more information if needed.

Thanks

## Reply by James Strawson (ModalAI staff) · 2022-01-06 00:59:03 UTC

Hi Matthew,

When you try to run voxl-logger with the hires camera it should have given the following error message:

```bash
voxl:/$ voxl-logger --cam hires --samples 1
connected to ch 0 cam server: /run/mpa/hires/
ERROR only support RAW8, RAW16, and FLOAT32 images right now
got NV21 instead
```

The reason these are the only formats currently supported is because it uses opencv to save/load images. OpenCV is quick enough for black and white images, but simply too slow to be practical for large color images.

As an experiment I just made a new branch of voxl-mpa-tools with a slow but functional switch-case for the NV21 images produced by the hires camera. This will work for saving one or two images, but won't be able to keep up with a steady 30fps stream.

Here is the code if you want to try:
https://gitlab.com/voxl-public/modal-pipe-architecture/voxl-mpa-tools/-/commit/633adfdaf8162548d5df4218243a32e06d2ea7b1

Migrating voxl-logger to use a faster image compression library and/or hardware acceleration is in the pipeline but I can't promise a release date for that I'm afraid.

I hope this helps,
James

## Reply by David Smyth · 2022-03-22 14:23:50 UTC

+1 for this functionality if possible. Would it be possible to merge the color branch into dev/master for the next release? If speed is a problem I think it would be acceptable to limit this to lower resolutions as a starting point