Merged in mjpeg-output-v4l (pull request #292)

Mjpeg output v4l

Approved-by: Saxon Milton <saxon.milton@gmail.com>

cmd/revid-cli/main.go

@@ -202,6 +202,8 @@ func handleFlags() config.Config {
 		cfg.InputCodec = codecutil.PCM
 	case "ADPCM":
 		cfg.InputCodec = codecutil.ADPCM
+	case "MJPEG":
+		cfg.InputCodec = codecutil.MJPEG
 	default:
 		log.Log(logger.Error, pkg+"bad input codec argument")
 	}

device/webcam/webcam.go

@@ -31,6 +31,7 @@ import (
 	"os/exec"
 	"strings"
 
+	"bitbucket.org/ausocean/av/codec/codecutil"
 	"bitbucket.org/ausocean/av/device"
 	"bitbucket.org/ausocean/av/revid/config"
 	"bitbucket.org/ausocean/utils/logger"
@@ -113,18 +114,31 @@ func (w *Webcam) Set(c config.Config) error {
 // Start will build the required arguments for ffmpeg and then execute the
 // command, piping video output where we can read using the Read method.
 func (w *Webcam) Start() error {
+	br := w.cfg.Bitrate * 1000
+
 	args := []string{
 		"-i", w.cfg.InputPath,
-		"-f", "h264",
 		"-r", fmt.Sprint(w.cfg.FrameRate),
+		"-b:v", fmt.Sprint(br),
+		"-s", fmt.Sprintf("%dx%d", w.cfg.Width, w.cfg.Height),
+	}
+
+	switch w.cfg.InputCodec {
+	default:
+		return fmt.Errorf("revid: invalid input codec: %v", w.cfg.InputCodec)
+	case codecutil.H264:
+		args = append(args,
+			"-f", "h264",
+			"-maxrate", fmt.Sprint(br),
+			"-bufsize", fmt.Sprint(br/2),
+		)
+	case codecutil.MJPEG:
+		args = append(args,
+			"-f", "mjpeg",
+		)
 	}
 
-	br := w.cfg.Bitrate * 1000
 	args = append(args,
-		"-b:v", fmt.Sprint(br),
-		"-maxrate", fmt.Sprint(br),
-		"-bufsize", fmt.Sprint(br/2),
-		"-s", fmt.Sprintf("%dx%d", w.cfg.Width, w.cfg.Height),
 		"-",
 	)
 

revid/revid.go

@@ -191,7 +191,15 @@ func (r *Revid) reset(c config.Config) error {
 					panic("unknown input codec for raspivid input")
 				}
 			case config.InputFile, config.InputV4L:
-				st = mts.EncodeH264
+				switch r.cfg.InputCodec {
+				case codecutil.H264:
+					st = mts.EncodeH264
+				case codecutil.MJPEG:
+					st = mts.EncodeMJPEG
+					encOptions = append(encOptions, mts.PacketBasedPSI(int(r.cfg.MinFrames)))
+				default:
+					panic("unknown input codec for v4l or input file input")
+				}
 			case config.InputRTSP:
 				switch r.cfg.InputCodec {
 				case codecutil.H265:
@@ -329,7 +337,12 @@ func (r *Revid) setupPipeline(mtsEnc func(dst io.WriteCloser, rate float64) (io.
 
 	case config.InputV4L:
 		r.input = webcam.New(r.cfg.Logger)
-		r.lexTo = h264.Lex
+		switch r.cfg.InputCodec {
+		case codecutil.H264:
+			r.lexTo = h264.Lex
+		case codecutil.MJPEG:
+			r.lexTo = mjpeg.Lex
+		}
 
 	case config.InputFile:
 		r.input = file.New()