* add chart header
* get all signal val from logs
* loop in selected range
* clear list before append
* automatically zoom on yaxis
* cleanup
* sync charts
* fix event_begin_sec
* set the color of rubber
* add TODO
* sync slider with charts
* keep video aspect ratio
* sync plot buttons
* reduce flickers
* cleanup
* refactor detail view
* clear counters
* more
use qcamera