P2AMP - Wav Player with FFT Spectrum analyzer
MXX
Posts: 22
Dear All,
I would like to share with you a small project I worked on during Xmas holidays.
It's a simple wav player (Winamp Style) running on the P2 Thing + LCD 4.3" (480x272) display with a nice FFT real-time spectrum analyzer.
It includes:
- Paletted display driver to save hub memory (130 KB vs 390 KB with 256 colors 8 bit palette)
- Different Fonts directly loaded from simple bitmap images
- Wav player based on @Rayman code with some additions (like interactive volume control etc ..)
- FFT for spectrum analyzer including windowing (hanning, hammin, flat-top, rectangular etc ..) and all related calculations for graphical representation of the spectrum.
I implemented my own FFT working on 16 bit signed samples (to save some memory) on a 4096 samples window updated every 1024 samples (audio @ 44.1 kHz 16 bit stereo).
4096 samples window at 44.1 kHz allows a good resolution at lower frequencies (approx 11 Hz).
This works on 4 cogs: main program, FFT, wav player and LCD.
Credits @Rayman for the player and LCD driver.
I can share details if interested.
Comments
"interested"
are you kidding? that's brilliant.
Looking forward to seeing the code.
Dave
Nice!
Nice one!
(Also I think I forgot to thank you for the cookies - came on time this year)
Thanks Dave,
here is the whole source code, it compiles with FlexProp.
FFT object also woks with propeller tool / PNut.
Runs on our P2 board (The P2 Thing), can be adapted to run on other boards too by defining the correct pins.
Enjoy!
Very pretty. I wonder if the output screen could be easily ported to be run over a VGA or DVI output...? Pure doubling gives 960x544 which could fit within an XGA formatted output and look even better if resolution was correspondingly increased a bit vertically and horizontally to 512x384. Might need some changes to your driver or if it's just palettized it could use my video driver in palette mode. A 512x384 video mode only needs 192kB in 8 bit palette mode so it should all fit in the hub RAM.