Added wav example and updated help output

Author: zeyus

README.md

@@ -66,7 +66,10 @@ python -m bluebox -h
 Output:
 
 ```
-usage: __main__.py [-h] [-l LENGTH] [-p PAUSE] [-a AMPLITUDE] [-s SAMPLE_RATE] [-m MF] [-d] [-b BACKEND] [-r PAD_PAUSE_DURATION] [-f FILE] [-P PIPE] [-S] [-i] [-v] [sequence]
+usage: python3 -m bluebox [-h] [-l LENGTH] [-p PAUSE] [-a AMPLITUDE] [-s SAMPLE_RATE] [-m MF]
+                          [-d] [-b BACKEND] [-o OUTPUT] [-r PAD_PAUSE_DURATION] [-f FILE]
+                          [-P PIPE] [-S] [-i] [-v]
+                          [sequence]
 
 Generate tone sequences.
 
@@ -75,22 +78,21 @@ positional arguments:
 
 options:
   -h, --help            show this help message and exit
-  -l LENGTH, --length LENGTH
-                        The length of each tone in milliseconds.
-  -p PAUSE, --pause PAUSE
-                        The length of the pause between tones in milliseconds.
-  -a AMPLITUDE, --amplitude AMPLITUDE
+  -l, --length LENGTH   The length of each tone in milliseconds.
+  -p, --pause PAUSE     The length of the pause between tones in milliseconds.
+  -a, --amplitude AMPLITUDE
                         The combined amplitude of the waveforms.
-  -s SAMPLE_RATE, --sample-rate SAMPLE_RATE
+  -s, --sample-rate SAMPLE_RATE
                         The sample rate of the waveforms.
-  -m MF, --mf MF        The MF to use e.g. dtmf, mf.
+  -m, --mf MF           The MF to use e.g. dtmf, mf.
   -d, --debug           Enable debug logging.
-  -b BACKEND, --backend BACKEND
-                        The backend to use for playing the waveforms.
-  -r PAD_PAUSE_DURATION, --pad-pause-duration PAD_PAUSE_DURATION
+  -b, --backend BACKEND
+                        The backend to use for playing the waveforms (pyaudio, wav, dummy).
+  -o, --output OUTPUT   Output file path (required for wav backend).
+  -r, --pad-pause-duration PAD_PAUSE_DURATION
                         The duration (ms) of the pause before/after sequence.
-  -f FILE, --file FILE  The file to read the sequence from.
-  -P PIPE, --pipe PIPE  Read the sequence from a pipe.
+  -f, --file FILE       The file to read the sequence from.
+  -P, --pipe PIPE       Read the sequence from a pipe.
   -S, --stdin           Read the sequence from stdin.
   -i, --interactive     Enter interactive mode.
   -v, --version         show program's version number and exit
@@ -114,6 +116,14 @@ uv run python -m bluebox 123456789
 python -m bluebox 123456789
 ```
 
+Write a wav file:
+
+```bash
+uv run python -m bluebox -b wav -o sequence.wav 1234567890
+# or with system python:
+python -m bluebox -b wav -o sequence.wav 1234567890
+```
+
 ### API
 
 You mainly need an `BaseMF` subclass instance and a `Sequencer` instance.
@@ -136,4 +146,6 @@ Same thing for audio backends.
 
 Currently there are two MF implementations (DTMF and MF), and two audio backends (PyAudio and Dummy).
 
+If you want to contribute, make a fork, and a branch. Please make any PR against develop.
+