Okay, so my previous post got deleted somehow.
So, I took someone's advice, never got the chance to thank them. It worked out
I figured out
wave_length = sample_rate / frequency;
That's pretty streight forward, makes sense to me.
Now, I'm having a problem with audio streams.
I create the stream and then here's how I'm filling it up
| 1 | #define SAMPLE_RATE 22000 |
| 2 | #define FREQUENCY 440.00 |
| 3 | |
| 4 | int i; |
| 5 | unsigned char *stream; |
| 6 | double saw; |
| 7 | double saw_speed; |
| 8 | double wavelength; |
| 9 | double half_wavelength; |
| 10 | AUDIOSTREAM *audio_buffer; |
| 11 | |
| 12 | audio_buffer = play_audio_stream( BUFFER_SIZE, 8, FALSE, |
| 13 | FREQUENCY, 255, 128 ); |
| 14 | wavelength = (SAMPLE_RATE/FREQUENCY); |
| 15 | half_wavelength = wavelength/2; |
| 16 | saw_speed = 255.00/half_wavelength; |
| 17 | |
| 18 | for(;;){ |
| 19 | stream = get_audio_stream_buffer( audio_buffer ); |
| 20 | if ( stream != NULL ){ |
| 21 | for ( i = 0; i < BUFFER_SIZE; i++ ){ |
| 22 | saw += saw_speed; |
| 23 | if ( saw > 255 ){ |
| 24 | saw_speed *= -1; |
| 25 | saw = 255-(saw-255); |
| 26 | } |
| 27 | if ( saw < 0 ){ |
| 28 | saw_speed *=-1; |
| 29 | saw = 0-saw; |
| 30 | } |
| 31 | stream<i> = (unsigned char)saw; |
| 32 | } |
| 33 | free_audio_stream_buffer( audio_buffer ); |
| 34 | } |
| 35 | } |
I'm not sure if the code above compiles and works, it's just a demonstration of what I'm doing. Okay, so...
It plays an A, but it's all choppy as if I'm not fully filling up the audio buffer. But clearly it says "play_audio_stream( BUFFER_SIZE... )" and "for ( i = 0; i < BUFFER_SIZE; i++ )" note usage of BUFFER_SIZE.
Thoughts?
]]>Hmm... Allegro.cc has been acting very strange on me as of late. Failing to post, hiding threads, etc...
Anyhow, it sounds like I'm not filling the buffer up completely. There's a little jitter in the note. The funny thing is, if I play - I think - a 'D', it sounds smooth, and that's it. No idea why.
Thanks again Miran for your help, your advice was perfect despite the small calculation error, I figured it out anyhow. (I seem to remember posting this comment earlier, but it never got posted).
Edit:
I think I may have figured it out. I was resetting the saw on every 'fill'
Thanks guys.
I think I may have figured it out. I was resetting the saw on every 'fill'
Yeah, when you get to the next buffer, you need to continue from whereyou left off the last time.
]]>Perhaps you clicked 'hide thread' by mistake.
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