isapi: support Hikvision AAC two-way talk

internal/isapi/README.md

@@ -12,3 +12,18 @@ streams:
     - rtsp://admin:password@192.168.1.123:554/Streaming/Channels/101
     - isapi://admin:password@192.168.1.123:80/
 ```
+
+## Codecs
+
+| Camera TwoWayAudio | Support |
+|--------------------|---------|
+| G.711ulaw / G.711alaw | Raw PCMU/PCMA (classic path) |
+| AAC | Length-prefixed ADTS over `/audioData` (`[u32be len][ADTS]`). WebRTC mic (PCMU/PCMA) is transcoded to AAC via `ffmpeg` |
+
+Requires `ffmpeg` on PATH when the camera is set to AAC and the browser sends G.711.
+
+## Notes
+
+- Session: `close` → brief settle → `open` → `PUT .../audioData?sessionId=...`
+- AAC sample rate is read from `audioSamplingRate` (typically 16 kHz)
+- Some firmware lists G.711 in capabilities but rejects `open` while AAC works — leave the camera on AAC

internal/isapi/init.go

@@ -1,13 +1,16 @@
 package isapi
 
 import (
+	"github.com/AlexxIT/go2rtc/internal/app"
 	"github.com/AlexxIT/go2rtc/internal/streams"
 	"github.com/AlexxIT/go2rtc/pkg/core"
-	"github.com/AlexxIT/go2rtc/pkg/isapi"
+	pkg "github.com/AlexxIT/go2rtc/pkg/isapi"
 )
 
 func Init() {
+	pkg.SetLogger(app.GetLogger("isapi"))
+
 	streams.HandleFunc("isapi", func(source string) (core.Producer, error) {
-		return isapi.Dial(source)
+		return pkg.Dial(source)
 	})
 }