Add option to export to CSV via sleap-convert and API

[eberrigan]

It would be convenient to be able to export predictions stored in .SLP files to .CSV (see linked discussion).

Enhancement plan

1. Add csv as an option for the --format flag in the sleap-convert CLI here:

sleap/sleap/io/convert.py

Lines 67 to 75 in 2d24296

	parser.add_argument(
	"--format",
	default="slp",
	help="Output format. Default ('slp') is SLEAP dataset; "
	"'analysis' results in analysis.h5 file; "
	"'analysis.nix' results in an analysis nix file;"
	"'h5' or 'json' results in SLEAP dataset "
	"with specified file format.",
	)

2. If csv format is requested, use csv=True in the sleap-convert CLI entrypoint function:

sleap/sleap/io/convert.py

Lines 165 to 172 in 2d24296

	write_analysis(
	labels,
	output_path=output_path,
	labels_path=args.input_path,
	all_frames=True,
	video=video,
	)

3. The CSV writing is already handled through the IO format backends, so we can just route it through by adding csv as an option in the actual analysis exporting writer:

sleap/sleap/io/convert.py

Lines 177 to 181 in 2d24296

	elif args.format in ("slp", "h5", "json"):
	output_path = f"{args.input_path}.{args.format}"
	print(f"Output SLEAP dataset: {output_path}")
	Labels.save_file(labels, output_path)

Discussed in #1629

^{Originally posted by talmo December 7, 2023}
In #1438, we added a feature to export tracks to CSV format from the GUI.

It would be great to be able to do that via the sleap-export CLI and the Labels.export() API.

For sleap-export, we just need to add CSV as a target format and pass in csv=True in the export call here.

For Labels.export(), we probably want to extend what's going on here.

We should also be sure to support the new functionality being added in #1624.

Relevant: #1627

[roaldarbol]

Any idea when you're cutting a new release? This feature would be great to have without having to build from source. :-)

[talmo]

Soon™ :)