Setting up a playlist for testing in BTS#

For testing that requires using the Cameras at BTS, a playlist with simulated images is needed. There are several already available playlists, but occasionally, one may desire to either update or create a new one. This document describes how to go about it.

Setting up a playlist for LATISS#

Usually, when we play back images, they are played back from the DAQ 2-day store (named like that for legacy reasons), so they need to be loaded. The one exception to this (currently) is LATISS at BTS. LATISS at BTS has no DAQ, so we emulate it using files on disk. This makes setting up a playlist somewhat different that the other cases.

1. Log into the machine where playlist are stored#

The machine where playlists and images are stored in BTS for latiss is auxtel-fp01.ls.lsst.org. You will need SSH access to this machine.

2. Copy the images needed for the new playlist#

The images for the new playlist need to be in .raw and .meta format. The easiest (and perhaps only) way to generate these files currently is to extract them from the 2-day store at the Summit on auxtel-fp01.cp.lsst.org. Despite its name, a lot of old images are still stored there.

  • ssh into auxtel-fp01.cp.lsst.org.

  • Use store commands to access the store:

    connect lat
ls raw/{image_id} # not do ls raw, as there is too much there
readRaw raw/{image_id} /tmp #this will generate the .raw and .meta files and copy them to /tmp

  • You can move those files to auxtel-fp01.ls.lsst.org via scp. They need to be copied into the directory /data/data/auxtel/playlist-data/emu/.

3. Set up the playlist#

Playlits are plain text files that specify a directory and a list of images. They are in the directory /home/ccs/playlists. Here is an example file:

[ccs@auxtel-fp01 playlists]$ cat default.plist
/data/data/auxtel/playlist-data/
emu
AT_O_20210218_000249
AT_O_20210218_000250
AT_O_20210218_000251
...

To define a new playlist simply create a new file in that directory listing the images you want to use. To verify the playlist was correctly set, you can use ccs-shell commands:

ccs-shell
set target ats-fp #for latiss
listPlaylists

Your new playlist should appear there.

4. Verify that the playlist can be loaded#

To verify that the playlist can actually be used in LOVE, try loading it by running the run_command script with the following configuration:

component: ATCamera #for latiss
cmd: play
parameters:
    playlist: {playlist name}

Once loaded, you should be able to take images using the simulated playlist. See further information on how to do this in Minimal Testing. You can also verify that the correct images were used by visually inspecting them in https://base-lsp.lsst.codes/rubintv/base.