Update demos installation section (#585)

demos/README.md

@@ -2,12 +2,39 @@
 
 ## Technical requirements
 
-- **FFmpeg**
+- **FFmpeg** (FFmpeg6 on Linux, FFmpeg 7 on MacOS)
 - **Gstreamer**
 - NodeJS + npm
 
 Before running demos, install JS dependencies with:
 
+```console
+npm install
+```
+LiveCompositor should run on any computer with modern GPU, but if you want to check detailed requirements, visit [requirements section in docs](https://compositor.live/docs/deployment/requirements).
+
+### MacOS installation guide
+
+1. Install FFmpeg 7
+```console
+brew install ffmpeg
+```
+
+2. Install GStreamer
+
+- Go to GStreamer website, download and open runtime installers (we tested 1.24 release, but should work on the others as well).
+- Check if directory `/Library/Frameworks/GStreamer.framework/Commands/` exists.
+- Add `/Library/Frameworks/GStreamer.framework/Commands/` to `PATH`.
+If you're using `zshrc` add: `export PATH="$PATH:/Library/Frameworks/GStreamer.framework/Commands"` to `~/.zshrc`
+
+3. Install `node`
+
+```console
+brew install node
+```
+
+4. Install JS dependencies
+
 ```console
 npm install
 ```
@@ -43,12 +70,12 @@ This example simulates TV broadcasting scenario.
 It demonstrate how you can combine build-in components with own shaders, customizing LiveCompositor for specific use-case, while utilizing GPU rendering acceleration.
 In this example, green-screen is removed from input stream with use of custom shader. Transformed input stream, background image, logo, and text are combined in output stream.
 
-### 3. Screen stream
+### 3. Live stream
 
 Run this example with:
 
 ```console
-npm run 3-screen_stream
+npm run 3-live_stream
 ```
 
 This example simulates live streaming screen footage with webcam.