add audio support, trying to manage MSD device

http/hw/stream/ffmpeg.go

@@ -13,6 +13,18 @@ import (
 // vp8
 //ffmpeg -re -i /dev/video0 -c:v libvpx -crf 10 -b:v 3M -deadline 1 -g 10 -error-resilient 1 -auto-alt-ref 1 -an -f rtp rtp://127.0.0.1:5004?pkt_size=1200
 
+/*
+arecord -D hw:0,0 -f cd -r 44100 -c 2 | /app/ffmpeg -re -init_hw_device rkmpp=hw -filter_hw_device hw \
+-f wav -thread_queue_size 4096 -i pipe:0 -f v4l2 -i /dev/video0 \
+-vf hwupload,scale_rkrga=h=720:force_original_aspect_ratio=1 \
+-c:v h264_rkmpp -flags +low_delay -b:v 6000000 -framerate 60 -g 10 \
+-map 0:a -c:a aac -b:a 128k -ar 44100 -ac 2 -f rtp rtp://127.0.0.1:5006?pkt_size=1200 \
+-map 1:v -f rtp rtp://127.0.0.1:5004?pkt_size=1200
+
+
+arecord -D hw:0,0 -f cd -r 44100 -c 2 | /app/ffmpeg -re -f wav -i pipe:0 -c:a aac -b:a 128k -ar 44100 -ac 2 -f rtp rtp://127.0.0.1:5006?pkt_size=1200
+*/
+
 // https://jsfiddle.net/z7ms3u5r/
 
 var ffmpeg *FFmpeg
@@ -40,10 +52,28 @@ func (f *FFmpeg) SetFPS(fps int) {
 	f.ChangeArgs(f.FormatArgs())
 }
 
+func (f *FFmpeg) SetResolution(height int) {
+	f.Height = height
+	if f.Height <= 0 {
+		f.Height = 1080
+	}
+
+	f.ChangeArgs(f.FormatArgs())
+}
+
+func (f *FFmpeg) SetGOP(gop int) {
+	f.GOP = gop
+	if f.GOP < 0 {
+		f.GOP = 0
+	}
+
+	f.ChangeArgs(f.FormatArgs())
+}
+
 func InitFFmpeg(path string, args []string) *FFmpeg {
 	ffmpeg = &FFmpeg{
 		ExtProcess: Init(path, args),
-		FFmpeg:     config.Get().FFmpeg,
+		FFmpeg:     config.Get().Video,
 	}
 	return ffmpeg
 }