Force key frame on PLI

Also make the ReadCloser an Controllable allows to uncouple
the controller implementation from the encoder.
This is not needed for the 2 codec controller already implemented (openh264 and vpx)
but is more future proof in case it required for other codecs.

.gitignore

@@ -13,3 +13,5 @@
 
 scripts/cross
 coverage.txt
+
+.idea

examples/go.sum

@@ -13,6 +13,7 @@ github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4
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@@ -21,6 +22,7 @@ github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrU
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@@ -36,18 +38,19 @@ github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
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@@ -60,6 +63,8 @@ github.com/pion/rtcp v1.2.6 h1:1zvwBbyd0TeEuuWftrd/4d++m+/kZSeiguxU61LFWpo=
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@@ -69,17 +74,14 @@ github.com/pion/srtp/v2 v2.0.2 h1:664iGzVmaY7KYS5M0gleY0DscRo9ReDfTxQrq4UgGoU=
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@@ -90,24 +92,32 @@ github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5
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 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20201224043029-2b0845dc783e/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
@@ -147,5 +161,6 @@ gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWD
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

go.mod

@@ -7,7 +7,9 @@ require (
 	github.com/gen2brain/malgo v0.10.35
 	github.com/google/uuid v1.3.0
 	github.com/kbinani/screenshot v0.0.0-20210720154843-7d3a670d8329
+	github.com/pion/interceptor v0.1.10
 	github.com/pion/logging v0.2.2
+	github.com/pion/rtcp v1.2.9
 	github.com/pion/rtp v1.7.13
 	github.com/pion/webrtc/v3 v3.1.34
 	golang.org/x/image v0.0.0-20220617043117-41969df76e82

ioreader.go

@@ -1,5 +1,7 @@
 package mediadevices
 
+import "github.com/pion/mediadevices/pkg/codec"
+
 type EncodedBuffer struct {
 	Data    []byte
 	Samples uint32
@@ -8,11 +10,13 @@ type EncodedBuffer struct {
 type EncodedReadCloser interface {
 	Read() (EncodedBuffer, func(), error)
 	Close() error
+	codec.Controllable
 }
 
 type encodedReadCloserImpl struct {
-	readFn  func() (EncodedBuffer, func(), error)
-	closeFn func() error
+	readFn       func() (EncodedBuffer, func(), error)
+	closeFn      func() error
+	controllerFn func() codec.EncoderController
 }
 
 func (r *encodedReadCloserImpl) Read() (EncodedBuffer, func(), error) {
@@ -23,9 +27,14 @@ func (r *encodedReadCloserImpl) Close() error {
 	return r.closeFn()
 }
 
+func (r *encodedReadCloserImpl) Controller() codec.EncoderController {
+	return r.controllerFn()
+}
+
 type encodedIOReadCloserImpl struct {
-	readFn  func([]byte) (int, error)
-	closeFn func() error
+	readFn     func([]byte) (int, error)
+	closeFn    func() error
+	controller func() codec.EncoderController
 }
 
 func newEncodedIOReadCloserImpl(reader EncodedReadCloser) *encodedIOReadCloserImpl {
@@ -48,7 +57,8 @@ func newEncodedIOReadCloserImpl(reader EncodedReadCloser) *encodedIOReadCloserIm
 			encoded.Data = encoded.Data[n:]
 			return n, nil
 		},
-		closeFn: reader.Close,
+		closeFn:    reader.Close,
+		controller: reader.Controller,
 	}
 }
 
@@ -59,3 +69,7 @@ func (r *encodedIOReadCloserImpl) Read(b []byte) (int, error) {
 func (r *encodedIOReadCloserImpl) Close() error {
 	return r.closeFn()
 }
+
+func (r *encodedIOReadCloserImpl) Controller() codec.EncoderController {
+	return r.controller()
+}

pkg/codec/codec.go

@@ -112,15 +112,37 @@ type VideoEncoderBuilder interface {
 	BuildVideoEncoder(r video.Reader, p prop.Media) (ReadCloser, error)
 }
 
-// ReadCloser is an io.ReadCloser with methods for rate limiting: SetBitRate and ForceKeyFrame
+// ReadCloser is an io.ReadCloser with a controller
 type ReadCloser interface {
 	Read() (b []byte, release func(), err error)
 	Close() error
+	Controllable
+}
+
+// EncoderController is the interface allowing to control the encoder behaviour after it's initialisation.
+// It will possibly have common control method in the future.
+// A controller can have optional methods represented by *Controller interfaces
+type EncoderController interface{}
+
+// Controllable is a interface representing a encoder which can be controlled
+// after it's initialisation with an EncoderController
+type Controllable interface {
+	Controller() EncoderController
+}
+
+// KeyFrameController is a interface representing an encoder that can be forced to produce key frame on demand
+type KeyFrameController interface {
+	EncoderController
+	// ForceKeyFrame forces the next frame to be a keyframe, aka intra-frame.
+	ForceKeyFrame() error
+}
+
+// BitRateController is a interface representing an encoder which can have a variable bit rate
+type BitRateController interface {
+	EncoderController
 	// SetBitRate sets current target bitrate, lower bitrate means smaller data will be transmitted
 	// but this also means that the quality will also be lower.
 	SetBitRate(int) error
-	// ForceKeyFrame forces the next frame to be a keyframe, aka intra-frame.
-	ForceKeyFrame() error
 }
 
 // BaseParams represents an codec's encoding properties

pkg/codec/mmal/mmal.go

@@ -91,12 +91,8 @@ func (e *encoder) Read() ([]byte, func(), error) {
 	return encoded, func() {}, err
 }
 
-func (e *encoder) SetBitRate(b int) error {
-	panic("SetBitRate is not implemented")
-}
-
-func (e *encoder) ForceKeyFrame() error {
-	panic("ForceKeyFrame is not implemented")
+func (e *encoder) Controller() codec.EncoderController {
+	return e
 }
 
 func (e *encoder) Close() error {

pkg/codec/mmal/mmal_test.go

@@ -4,6 +4,7 @@ import (
 	"image"
 	"testing"
 
+	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/codec/internal/codectest"
 	"github.com/pion/mediadevices/pkg/frame"
 	"github.com/pion/mediadevices/pkg/prop"
@@ -44,3 +45,21 @@ func TestEncoder(t *testing.T) {
 		})
 	})
 }
+
+func TestShouldImplementBitRateControl(t *testing.T) {
+	t.SkipNow() // TODO: Implement bit rate control
+
+	e := &encoder{}
+	if _, ok := e.Controller().(codec.BitRateController); !ok {
+		t.Error()
+	}
+}
+
+func TestShouldImplementKeyFrameControl(t *testing.T) {
+	t.SkipNow() // TODO: Implement key frame control
+
+	e := &encoder{}
+	if _, ok := e.Controller().(codec.KeyFrameController); !ok {
+		t.Error()
+	}
+}

pkg/codec/openh264/openh264.go

@@ -90,15 +90,15 @@ func (e *encoder) Read() ([]byte, func(), error) {
 	return encoded, func() {}, nil
 }
 
-func (e *encoder) SetBitRate(b int) error {
-	panic("SetBitRate is not implemented")
-}
-
 func (e *encoder) ForceKeyFrame() error {
 	e.engine.force_key_frame = C.int(1)
 	return nil
 }
 
+func (e *encoder) Controller() codec.EncoderController {
+	return e
+}
+
 func (e *encoder) Close() error {
 	e.mu.Lock()
 	defer e.mu.Unlock()

pkg/codec/openh264/openh264_test.go

@@ -4,11 +4,28 @@ import (
 	"image"
 	"testing"
 
+	"github.com/pion/mediadevices/pkg/codec"
 	"github.com/pion/mediadevices/pkg/codec/internal/codectest"
 	"github.com/pion/mediadevices/pkg/frame"
 	"github.com/pion/mediadevices/pkg/prop"
 )
 
+func TestShouldImplementBitRateControl(t *testing.T) {
+	t.SkipNow() // TODO: Implement bit rate control
+
+	e := &encoder{}
+	if _, ok := e.Controller().(codec.BitRateController); !ok {
+		t.Error()
+	}
+}
+
+func TestShouldImplementKeyFrameControl(t *testing.T) {
+	e := &encoder{}
+	if _, ok := e.Controller().(codec.KeyFrameController); !ok {
+		t.Error()
+	}
+}
+
 func TestEncoder(t *testing.T) {
 	t.Run("SimpleRead", func(t *testing.T) {
 		p, err := NewParams()

pkg/codec/opus/opus.go

@@ -121,8 +121,8 @@ func (e *encoder) SetBitRate(bitRate int) error {
 	return nil
 }
 
-func (e *encoder) ForceKeyFrame() error {
-	panic("ForceKeyFrame is not implemented")
+func (e *encoder) Controller() codec.EncoderController {
+	return e
 }
 
 func (e *encoder) Close() error {