Everything started from the desire to develop a mobile application, for both iOS and Android, that permits video processing similar to Adobe Premiere Pro. The purpose of the app is creating video compositions of other videos and images based on predefined templates. The MyBlender application is a delivery vehicle of a complex underlying publishing platform called ThemeMaker. This web-based creative tool, end-to-end content and user management system allows non-technical graphical artists to create stunning-looking Themes in only a few hours without any prior coding knowledge. Usually, custom creative treatments take months to program. One of the most important features is the fact that Themes can be published to the MyBlender app installed on devices without requiring it to be updated in the app store. This feature permits the timely publication of specific event-based and seasonal themes. More details on MyBlender’s features and unique selling proposal can be found here.

MyBlender’s Video Processing Engine

The most critical feature of the mobile application was the video processing core, which not only needed to support a multitude of effects, but also minimise the composition time. If you would like to read more about our video processing core please follow this article on our blog.

In order to make this possible, extensive knowledge about GPU, shaders, threading, etc was required. There are over 15 different filters that can be applied independently and each filter was designed to be customisable. Filters may require 1, 2 or 3 inputs and will provide a single output.

A major feature of the video processing core is the fact that new effects can be added with very little effort because HyperSense developed a plug-and-play modular system.

Effects available to be added to individual images, entire or specific parts of videos were made available by a custom video core processor that included:

• alpha;
• black and white;
• blur;
• color overlay;
• color invert;
• zoom;
• scale;
• transitions;
• sepia effects;
• saturation;
• gamma;
• edge highlighting;
• edge blur;
• contrast.

Handling multiple videos required a set of transitions, some of which were based on individual filters. Transitions available to be applied by the processing core include:

• crossfade;
• blur;
• white flash;
• movement;
• scale in and out.

MyBlender also offers the option of using complex transitions that require auxiliary media files, such as:

• overlays;
• chroma keying;
• trackmatte.

These effects can be used for both transitions and individual files, based on the timing of the effect.

The video processing core’s audio module permitted the manipulation of video sound volume as well as the control over sound mixing when dealing with several overlapping audio sources.

To make it more user-friendly and overcome the design limits, the core functionality is made available through a series of themes. One downside of these themes is the limitation of the engine processing capability. For example, the video processing core is capable of generating videos of any length, however, MyBlender was released with video outputs limited to 6 and 15 seconds.

MyBlender’s themes also control:

• The number of videos or photos that the user can select, MyBlender offers themes for 1-6 media sources;
• the effects that can be applied and the order in which they are applied: – background;
• effects;
• transitions;
• overlays;
• chroma keys;
• trackmattes.
• sound sources and volumes: – background music;
• user sources;
• theme sounds.

MyBlender and it’s video processing core can handle both landscape and portrait selected inputs. In order to accommodate for portrait and landscape sources, the themes contain specific rules for each orientation. This is a critical function for overlays, motions and an overall aesthetic feel of the exported video composition. 

All outputs are exported in landscape orientation, at 30 FPS. The frame rate was added to optimise the processing time. The orientation limit was a feature requested by the theme and not a limit of the video processing engine.

MyBlender is able to process videos faster than the time needed to play them, therefore, once the user has selected the image and video source, the preview rendering starts instantaneously. For example, for a 6 second export MyBlender requires only 3 seconds to export the video on an iPhone 5S.

MyBlender’s Web ThemeMaker

The ThemeMaker tool defines the overall creative look of any content combination and manages the creative assets such as graphics, video backgrounds, music and sound effects associated with the Theme. ThemeMaker also delivers them over-the-air to the mobile application via a proprietary compression algorithm that limits the size of the Theme assets. Themes include a Theme icon and three interstitial screens. They can be branded for a sponsor and linked to commerce opportunities such as ticket sales, music in the iTunes or Play store or other mobile web pages integrated seamlessly into the MyBlender application.

The video designer creates templates using the web platform called ThemeMaker and publishes them in order to synchronise the device. The mobile applications are optimised not only from the process duration perspective, but the device limitations and particularities are also taken into account. The application needs to handle a creation process with up to 6 user inputs, images or videos, as well as the template resources. Templates support chroma effects, track matte, background images and videos and custom text overlays. Also, different sounds and audio mix composition controls are available.