Added muxer header option

libav/muxer.go

@@ -20,6 +20,7 @@ type Muxer struct {
 	c                    *astikit.Chan
 	formatContext        *astiav.FormatContext
 	eh                   *astiencoder.EventHandler
+	header               map[string]string
 	o                    *sync.Once
 	p                    *pktPool
 	restamper            PktRestamper
@@ -32,6 +33,7 @@ type Muxer struct {
 type MuxerOptions struct {
 	Format     *astiav.OutputFormat
 	FormatName string
+	Header     map[string]string
 	Node       astiencoder.NodeOptions
 	Restamper  PktRestamper
 	URL        string
@@ -47,6 +49,7 @@ func NewMuxer(o MuxerOptions, eh *astiencoder.EventHandler, c *astikit.Closer, s
 	m = &Muxer{
 		c:         astikit.NewChan(astikit.ChanOptions{ProcessAll: true}),
 		eh:        eh,
+		header:    o.Header,
 		o:         &sync.Once{},
 		restamper: o.Restamper,
 	}
@@ -150,9 +153,22 @@ func (m *Muxer) FormatContext() *astiav.FormatContext {
 // Start starts the muxer
 func (m *Muxer) Start(ctx context.Context, t astiencoder.CreateTaskFunc) {
 	m.BaseNode.Start(ctx, t, func(t *astikit.Task) {
+		// Create header dictionary
+		var d *astiav.Dictionary
+		if len(m.header) > 0 {
+			d = astiav.NewDictionary()
+			defer d.Free()
+			for k, v := range m.header {
+				if err := d.Set(k, v, astiav.NewDictionaryFlags()); err != nil {
+					emitError(m, m.eh, err, "setting header dictionary %s=%s", k, v)
+					return
+				}
+			}
+		}
+
 		// Make sure to write header once
 		var err error
-		m.o.Do(func() { err = m.formatContext.WriteHeader(nil) })
+		m.o.Do(func() { err = m.formatContext.WriteHeader(d) })
 		if err != nil {
 			emitError(m, m.eh, err, "writing header")
 			return