DATV demod: updated documentation

plugins/channelrx/demoddatv/readme.md

@@ -114,13 +114,13 @@ Gauge that shows percentage of buffer queue length
 
 ![DATV Demodulator plugin video GUI](../../../doc/img/DATVDemod_pluginVideo.png)
 
-<h5>B.2b.1: Image thumbnail</h4>
+<h5>B.2b.1: Image</h5>
 
-Use full screen button (5) to switch to full screen video
+The decoded video is displayed here
 
-<h5>B.2b.2: Stream information</h4>
+<h5>B.2b.2: Stream information</h5>
 
-<h5>B.2b.3: Stream decoding status</h4>
+<h5>B.2b.3: Stream decoding status</h5>
 
 These non clickable checkboxes report the decoding status (checked when OK):
 
@@ -129,8 +129,29 @@ These non clickable checkboxes report the decoding status (checked when OK):
   - video: video data detected
   - decoding: video being decoded
 
-<h5>B.2b.4: Play/pause video playback</h4>
+<h5>B.2b.4: Video mute</h5>
 
-<h5>B.2b.4: Full screen mode</h4>
+Toggle button to pause/run video decoding. This also indicates the video status:
+
+  - Grey (no color): there is no video stream
+  - Green: a video stream is present and successfully decoded
+  - Red: a video stream is present but decoding fails
+
+<h5>B.2b.5: Audio mute</h5>
+
+Toggle button to pause/run audio decoding. This also indicates the audio status:
+
+  - Grey (no color): there is no audio stream
+  - Green: an audio stream is present and successfully decoded
+  - Red: an audio stream is present but decoding fails
+
+In addition right clicking on the button will give you access to the audio device selection dialog
+
+<h5>B.2b.6: Audio volume</h5>
+
+Show the audio volume on a 0 to 100 scale. The actual coefficient applied to the audio samples follows a logarithmic rule where 0 corresponds to 0.01, 50 to 0.1 and 100 to 1.0
+
+<h5>B.2b.7: Audio volume control</h5>
+
+Use this slider to control the value (0 to 100) of the audio volume.
 
-Click on this button to see video in full screen mode then click anywhere on the screen to exit full screen mode