Epic Labs has “open-sourced” a tool to compare visual quality of two synchronized videos, a project lead by Adrián Caballero (@adripanico)
This comparator -a JavaScript library- is a small part of LightFlow video optimizer portal (www.lightflow.media).
Just follow this Epic link: https://github.com/epiclabs-io/epic-video-comparator
The comparator was developed to prove that videos processed through LightFlow, despite the remarkable decrease in bitrate and underlying savings, were not experiencing any quality drop. It enables two videos to be synchronously playbacked and compared frame by frame thanks to the PID controller mechanism over the playback rate of each video. For ABR videos, it is also possible to select the desire quality level to playback. This tool also provides some statistical data such as dropped frames or video start-up time.
Interview with Adrián Caballero, Epic Engineer.
Why did Epic Labs decide to open source this tool?
When LightFlow was introduced to the market there were many demonstrations to clients and partners. In that sessions we could notice that the comparator was very successful and both, prospective customers and partners, felt in love with this particular feature. That’s the reason why we decided to bring it out of the LightFlow ecosystem as a standalone component, and finally bring it to the open source community.
What does this mean to you?
It is really amazing to be part of a company that bet on open source and I feel so proud to be collaborating with the community. It’s giving back what we’ve taken from it. At the end of the day mostly all developers use pieces of software from here and there to build up much bigger and complex solutions. This is a full circle for me, as we have provided a great tool and I’m sure the community will provide useful feedback and improvements. This is not the end of the path, it is just the very beginning.
What will the person who chooses to use this comparator be able to measure?
As well as visual quality using a slider that can be moved from side to side, it also shows buffer length, video start-up time and dropped frames, providing also detailed data for each video in terms of resolution, bitrate, or codec. It’s remarkable that the user can incorporate any statistics considered relevant or not showing anything at all.
What has been the big challenge for you?
When programming for the community you have to bear in mind that any other user must understand your work. I focused in typing clean code and documentation and learning the best way to publish in GitHub and npm. I also learned on how to integrate it with CI platforms to ensure that each new commit is properly tested and deployed as a demo page.
There has been a creative process behind this?
During the development of LightFlow, in every final sprint demo, there were many feedback comments taken in mind when shaping-up this tool. There has been a lot of iterations up to this publication in GitHub. For sure it will change a lot in the future and that is precisely the magic behind software development.
Of course there has been creativity. There is a bit of each one of the people from Epic Labs in this tool and in every solution that we provide, and creativity is the one of the pillars of this company.
