A mobile video editing app that syncronizes transitions/cuts with background tracks' beats. Developed with Flutter and FFMPEG.
A video editing project, that includes several clips and audio tracks. Editable and exportable to a video file.
A music file with a fixed BPM value. Currently has to start on the first beat of a bar. To work best, should also have a 4/4 or 2/4 time signature.
A clip is a portion of a video file that is included in a project. Clips have a duration measured in beats, that translates to a number of seconds depending on the Audio Track that is played in the background of the clip. The exported project will be the sequence of its clips, with Audio Tracks' sound synced due to the beat-based durations of the clips.
Holds user preferences and the paths and names of each user-created project.
This project is a Flutter application.
A few resources to get you started if this is your first Flutter project:
For help getting started with Flutter, view our online documentation, which offers tutorials, samples, guidance on mobile development, and a full API reference.
Before running with flutter run, please make sure the serializeable models have been generated with flutter pub run build_runner [watch]. Otherwise, there will be compilation errors.
The architecture is MVC-based and split into controller, model, redux and view folders:
controllercontains the most logic intensive tasks, such as: building FFMPEG arguments for previewing and exporting a project; saving and loading projects and app preferences.modelcontains the main models covered in the Key Concepts section of this readmereduxcontains redux-specific models/states, actions and reducersviewcontains the UI of the app
Under the controller/ffmpeg_build/ffmpeg_abstraction folder, there are many "stream" classes. These help and abstract ffmpeg arguments creation. For example:
OutputToFileStream(
'output.mp4',
ConcatenateFilterStream([
SourceFileStream(FileInput('input1.mp4')),
SourceFileStream(FileInput('input2.mp4'))
])
)
will concatenate files input1.mp4 and input2.mp4 and output to output.mp4.
As a more complex example, here is a simplified diagram for the FFMPEG arguments that allow project preview:
