av/filter/basic.go

63 lines
1.8 KiB
Go

// +build !circleci
/*
DESCRIPTION
A filter that detects motion and discards frames without motion. The
filter uses a Mixture of Gaussians method (MoG) to determine what is
background and what is foreground.
AUTHORS
Scott Barnard <scott@ausocean.org>
LICENSE
mog.go is Copyright (C) 2019 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package filter
import (
"io"
)
// MOGFilter is a filter that provides basic motion detection. MoG is short for
// Mixture of Gaussians method.
type BasicFilter struct {
dst io.WriteCloser
}
// NewMOGFilter returns a pointer to a new MOGFilter struct.
func NewBasicFilter(dst io.WriteCloser) *BasicFilter {
return &BasicFilter{dst}
}
// Implements io.Closer.
// Close frees resources used by gocv, because it has to be done manually, due to
// it using c-go.
func (m *BasicFilter) Close() error {
return nil
}
// Implements io.Writer.
// Write applies the motion filter to the video stream. Only frames with motion
// are written to the destination encoder, frames without are discarded.
func (m *BasicFilter) Write(f []byte) (int, error) {
//decode MJPEG
//for all frames find difference in this frame from last frames
return m.dst.Write(f)
}