Adds crop_to_roi config option

Adds crop_to_roi config option which if True, and an roi is configured, will crop the image to the roi before processing with Deepstack. This may improve accuracy since only the roi is considered in processing

Credit @wizmo2 via #27

Save files with microseconds in timestamp

Prevent condition where multiple files written in a second interval will overwrite one another

Fix device_state_attributes warnings

Merge pull request #261 from covid10/master

Fix for device_state_attributes warnings

Remove unused const

to prevent an issue in next HA release

PR #256

Bumps pillow dependency

Merge pull request #244 from robmarkcole/dependabot/pip/pillow-8.2.0

Bump pillow from 8.1.1 to 8.2.0

Optionally save png files

Adds a new config arg save_file_format which can optionally be png to save images as png format instead of the default jpg. png files have less compression so the text annotations are easier to read.

Note that the optional arg always_save_latest_jpg is now renamed to always_save_latest_file since this can be either a jpg or png now

ref #224

Adds the Summary back

Adds the Summary back, which was removed in v4.0

Adds save smaller jpg and always save latest options

This minor release has not breaking changes and adds two new features.

1. Smaller images can now be saved using the scale config variable, this should save some disk space for people with many high resolution cameras. Thanks @jodur for contributing this in #201

2. It is useful to see the last image processed by Deepstack even if there were no targets detected. This is now possible by configuring always_save_latest_jpg: True. PR #204

Please keep the feature requests coming :-)

Allow setting a confidence per target

Previously all targets had to use the same confidence threshold for detections. This was very limiting, as some classes are detected more easily by Deepstack than others. In this release you can now configure a confidence per target, and also for types of target. An example of the new config is below:

    targets:
      - target: vehicle
        confidence: 60
      - target: car
        confidence: 40

Here we are saying 'alert me about any vehicle with confidence above 60%, but I particularly care about cars (which is a type of vehicle) so alert me about any car above 40%'.

Note this is a breaking change only if you have configured targets, and you will need to update your config. If you have not configured targets your config is unaffected.

Allow setting object_type as target

Allow setting object_type as target, example config in readme