From d70a3ed3433d7f5edec118e6c0c943a3500730bb Mon Sep 17 00:00:00 2001
From: Cedric Verstraeten <cedric@verstraeten.io>
Date: Tue, 21 Feb 2023 22:44:56 +0100
Subject: [PATCH] do not reload decoder if same settings

---
 machinery/src/capture/IPCamera.go    | 12 ++++++++++
 machinery/src/components/Kerberos.go | 36 ++++++++++++++++++++++------
 machinery/src/models/Camera.go       | 14 +++++++++++
 3 files changed, 55 insertions(+), 7 deletions(-)
 create mode 100644 machinery/src/models/Camera.go

diff --git a/machinery/src/capture/IPCamera.go b/machinery/src/capture/IPCamera.go
index 587ac86..fb39cb1 100644
--- a/machinery/src/capture/IPCamera.go
+++ b/machinery/src/capture/IPCamera.go
@@ -25,6 +25,18 @@ func OpenRTSP(url string) (av.DemuxCloser, []av.CodecData, error) {
 	return nil, []av.CodecData{}, err
 }
 
+func GetVideoStream(streams []av.CodecData) (av.CodecData, error) {
+	var videoStream av.CodecData
+	for _, stream := range streams {
+		if stream.Type().IsAudio() {
+			//astream := stream.(av.AudioCodecData)
+		} else if stream.Type().IsVideo() {
+			videoStream = stream
+		}
+	}
+	return videoStream, nil
+}
+
 func GetVideoDecoder(decoder *ffmpeg.VideoDecoder, streams []av.CodecData) {
 	// Load video codec
 	var vstream av.VideoCodecData
diff --git a/machinery/src/components/Kerberos.go b/machinery/src/components/Kerberos.go
index 0aeba90..9b67b03 100644
--- a/machinery/src/components/Kerberos.go
+++ b/machinery/src/components/Kerberos.go
@@ -61,13 +61,14 @@ func Bootstrap(configuration *models.Configuration, communication *models.Commun
 	// Create some global variables
 	decoder := &ffmpeg.VideoDecoder{}
 	subDecoder := &ffmpeg.VideoDecoder{}
+	cameraSettings := &models.Camera{}
 
 	// Run the agent and fire up all the other
 	// goroutines which do image capture, motion detection, onvif, etc.
 
 	for {
 		// This will blocking until receiving a signal to be restarted, reconfigured, stopped, etc.
-		status := RunAgent(configuration, communication, uptimeStart, decoder, subDecoder)
+		status := RunAgent(configuration, communication, uptimeStart, cameraSettings, decoder, subDecoder)
 		if status == "stop" {
 			break
 		}
@@ -77,7 +78,7 @@ func Bootstrap(configuration *models.Configuration, communication *models.Commun
 	log.Log.Debug("Bootstrap: finished")
 }
 
-func RunAgent(configuration *models.Configuration, communication *models.Communication, uptimeStart time.Time, decoder *ffmpeg.VideoDecoder, subDecoder *ffmpeg.VideoDecoder) string {
+func RunAgent(configuration *models.Configuration, communication *models.Communication, uptimeStart time.Time, cameraSettings *models.Camera, decoder *ffmpeg.VideoDecoder, subDecoder *ffmpeg.VideoDecoder) string {
 	log.Log.Debug("RunAgent: started")
 
 	config := configuration.Config
@@ -113,12 +114,33 @@ func RunAgent(configuration *models.Configuration, communication *models.Communi
 			}
 		}
 
-		// At some routines we will need to decode the image.
-		// Make sure its properly locked as we only have a single decoder.
-		capture.GetVideoDecoder(decoder, streams)
+		// We will initialise the camera settings object
+		// so we can check if the camera settings have changed, and we need
+		// to reload the decoders.
+		videoStream, _ := capture.GetVideoStream(streams)
+		num, denum := videoStream.(av.VideoCodecData).Framerate()
+		width := videoStream.(av.VideoCodecData).Width()
+		height := videoStream.(av.VideoCodecData).Height()
+
+		if cameraSettings.RTSP != rtspUrl || cameraSettings.SubRTSP != subRtspUrl || cameraSettings.Width != width || cameraSettings.Height != height || cameraSettings.Num != num || cameraSettings.Denum != denum || cameraSettings.Codec != videoStream.(av.VideoCodecData).Type() {
+			// At some routines we will need to decode the image.
+			// Make sure its properly locked as we only have a single decoder.
+			log.Log.Info("RunAgent: camera settings changed, reloading decoder")
+			capture.GetVideoDecoder(decoder, streams)
+			if subStreamEnabled {
+				capture.GetVideoDecoder(subDecoder, subStreams)
+			}
 
-		if subStreamEnabled {
-			capture.GetVideoDecoder(subDecoder, subStreams)
+			cameraSettings.RTSP = rtspUrl
+			cameraSettings.SubRTSP = subRtspUrl
+			cameraSettings.Width = width
+			cameraSettings.Height = height
+			cameraSettings.Framerate = float64(num) / float64(denum)
+			cameraSettings.Num = num
+			cameraSettings.Denum = denum
+			cameraSettings.Codec = videoStream.(av.VideoCodecData).Type()
+		} else {
+			log.Log.Info("RunAgent: camera settings did not change, keeping decoder")
 		}
 
 		communication.Decoder = decoder
diff --git a/machinery/src/models/Camera.go b/machinery/src/models/Camera.go
new file mode 100644
index 0000000..a7c2fbd
--- /dev/null
+++ b/machinery/src/models/Camera.go
@@ -0,0 +1,14 @@
+package models
+
+import "github.com/kerberos-io/joy4/av"
+
+type Camera struct {
+	Width     int
+	Height    int
+	Num       int
+	Denum     int
+	Framerate float64
+	RTSP      string
+	SubRTSP   string
+	Codec     av.CodecType
+}