DH electronics: HMI frameworks or browser

Graphics Frameworks

As soon as a display is to be used in an embedded device such as our DHMI, the question of the right graphics framework arises. As there are a wide variety of frameworks, we have compared three relevant examples here and highlighted the advantages and disadvantages.

License costs free and open source
Low hardware requirements, GPU usage optional
Existing Yocto integration

Not the same graphical performance as Qt or Flutter

Market leader
GPU is required for good performance.
Existing Yocto integration
Existing user base with support forum

License costs to get decent LTS support

License costs free and open source
Cross-platform portability (Android/Linux/OSX/...)
Large user base
Useful documentation and examples supported by Google

Requires powerful hardware (CPU and GPU)
Yocto integration of meta-flutter is currently not optimal

WebKit vs. Chromium

WPEWebkit is a port of the Webkit browser engine used by Safari and specialized for embedded Linux. Cog is a lightweight Lanucher for WPEWebkit and comes with WPEWebkit. Chromium, on the other hand, is the open-source version of Google Chrome and almost all popular browsers such as Edge, Opera and Brave use Chromium as their base. In the following, we would like to highlight some of the advantages and disadvantages of the two web browsers for embedded systems.

Benefits of WPEWebKit

Optimized for embedded devices with weaker hardware
Very lightweight (less memory required in the final image)
Good integration in Yocto/OpenEmbedded
Compatible with many web frameworks (substructure of Safari)

Disadvantages of WPEWebKit

Only kiosk mode available for Cog without GUI for navigation
Moderate use of multicore

You can find the corresponding Yocto layer from Webkit here

Advantages of Chromium

Chromium based browsers dominate the browser market
Very good compatibility with many web frameworks
Good handling of multicore

Disadvantages of Chromium

Resource-intensive due to lack of optimization for embedded systems

The integration in Yocto/Openembedded and the implementation of updates are complex

You can find the corresponding Yocto layer of Chromium here

Here you can find our DHMI standard products

Name	Purpose	Lifetime	Type	Provider
CookieConsent	Saves your consent to using cookies.	1 year	HTML	Website
fe_typo_user	Assigns your browser to a session on the server. This data influences the content you see and is not evaluated or processed by us.	session	HTTP	Website

Name	Purpose	Lifetime	Type	Provider
_ga	Is used to differentiate between users.	2 years	HTML	Google
_gat	Is used to throttle the polling rate.	1 day	HTML	Google
_gid	Is used to differentiate between users.	1 day	HTML	Google
_ga_--container-id--	Saves the current status of the session.	2 years	HTML	Google
_gac_--property-id--	Is used to evaluate campaigns created with Google Analytics.	3 months	HTML	Google
_gcl_au	Used by Google AdSense for experimenting with advertisement efficiency across websites using their services.	3 months	HTML	Google
AMP_TOKEN	Contains a token that can be used to retrieve a client ID from the AMP Client ID service. Other possible values are opt-out, inflight request, or an error retrieving a client ID from the AMP Client ID service.	1 year	HTML	Google
_dc_gtm_--property-id--	Certain data is only sent to Google Analytics a maximum of once per minute. The cookie has a lifetime of one minute. As long as it is set, certain data transfers are prevented.	2 years	HTML	Google