diff options
Diffstat (limited to 'mpeglib/lib/util/audio/audioIO_BeOS.cpp')
| -rw-r--r-- | mpeglib/lib/util/audio/audioIO_BeOS.cpp | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/mpeglib/lib/util/audio/audioIO_BeOS.cpp b/mpeglib/lib/util/audio/audioIO_BeOS.cpp new file mode 100644 index 00000000..ae4cf5a1 --- /dev/null +++ b/mpeglib/lib/util/audio/audioIO_BeOS.cpp @@ -0,0 +1,227 @@ +// +// BeOS code for amp-0.7.4, (C) 1997 Andy Lo A Foe +// + + +#include <MediaKit.h> +#include <KernelKit.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "transform.h" +#include "audioIO.h" +#include "audio.h" + +// Define the streambuf size here. streambuf is used +// as a simple fit buffer. + +#define STREAMBUF_SIZE (32*1152) + +long bytes_in_streambuf; + +// streambuf definition and base indicator + +BSubscriber *the_sub; +BDACStream *the_stream; + +sem_id ok_to_read; +sem_id ok_to_write; + + +char streambuf[STREAMBUF_SIZE]; +char *readbase; + +static int au_vol = 100; + +// Define our own printout function since we are +// first writing in the streambuf (not needed, I think, +// but I don't know if the DACStream accepts a buffer +// size of 1152. Try it... + +void printout(void) +{ +if (A_WRITE_TO_FILE) { +#ifndef NO_BYTE_SWAPPING +int i,j; +short *ptr; + + if (nch==2) { + ptr=(short*)stereo_samples; + i=j=32 * 18 * 2; + } else { + ptr=(short*)mono_samples; + i=j=32 * 18; + } + + for (;i>=0;--i) + ptr[i] = ptr[i] << 8 | ptr[i] >> 8; +#endif + + if (nch==2) + fwrite(stereo_samples,1,sizeof stereo_samples,out_file); + else + fwrite(mono_samples,1,sizeof mono_samples,out_file); +} + + + if (A_AUDIO_PLAY) { + static char au_buf[STREAMBUF_SIZE]; + static int au_ptr =0, avail = 0; + static int num_smp; + static char *readbase = &au_buf[0]; + + // Write amount of samples to copy somewhere + num_smp = (nch == 2 ? sizeof stereo_samples : sizeof mono_samples); + + // Copy samples in the fit buffer + memcpy(au_buf+au_ptr,(nch == 2 ? (char *)stereo_samples : (char *)mono_samples), + num_smp); + + // Increase fit buffer pointer and available sample count + au_ptr+=num_smp; + avail+=num_smp; + + if (avail >= 4096) { // Are there enough smps to feed the stream? + audioWrite((char*)readbase,4096); // Feed it! + readbase+=4096; // Increase readbase + avail-=4096; // Decrease avail smps count + if (au_ptr == STREAMBUF_SIZE) { // At end of fit buffer? + au_ptr=0; // Reset all pointers + readbase=&au_buf[0]; + } + } + } + +} + + +// Fake Buffer functions, just to keep the sources clean, +// buffer.c should not be included in the link process... + +int AUDIO_BUFFER_SIZE; + +int +audioBufferOpen(int frequency, int stereo, int volume) +{ + audioOpen(frequency, stereo, volume); +} + + +inline void +audioBufferWrite(char *buf,int bytes) +{ + audioWrite(buf, bytes); +} + + +void +audioBufferClose() +{ + audioClose(); +} + + +int audioRead(char *buffer, int count) +{ + //printf("acquiring ok_to_read (%d bytes)\n", count); + if (acquire_sem(ok_to_read)==B_NO_ERROR) { + for (register int i=0; i < count;i++) { + *(buffer++)+=*(readbase++); + } + bytes_in_streambuf-=count; + + if (bytes_in_streambuf <= 0) { + release_sem(ok_to_write); + bytes_in_streambuf = 0; + } else { + release_sem(ok_to_read); + } + } + return (0); +} + + +bool stream_func(void *arg, char *buf, size_t count, void *header) +{ + audioRead(buf, count); + return TRUE; +} + +void audioOpen() { + readbase = &streambuf[0]; + + bytes_in_streambuf = 0; + + the_sub = new BSubscriber("amp DAC writer"); + the_stream = new BDACStream(); + + the_sub->Subscribe(the_stream); + + the_stream->SetSamplingRate(frequency); + + // Create semaphores + ok_to_read = create_sem(0, "read sem"); + ok_to_write = create_sem(1, "write sem"); + +} + +void audioInit(int sampleSize,int frequency, int stereo) +{ + + // Initialize the streambuf + bytes_in_streambuf = 0; + memset(&streambuf, 0, STREAMBUF_SIZE); + + + // Enter the stream + the_sub->EnterStream(NULL, TRUE, NULL, stream_func, NULL, TRUE); +} + + +void audioSetVolume(int volume) +{ + if (volume > 128) // This allows for a modest volume boost + volume = 128; + au_vol = volume; +} + + +void audioClose() +{ + the_sub->ExitStream(TRUE); + the_sub->Unsubscribe(); + + delete_sem(ok_to_read); + delete_sem(ok_to_write); + + delete the_sub; + delete the_stream; +} + + +// audioWrite is called from the player thread + +int audioWrite(char *buffer, int count) +{ + //printf("acquiring ok_to_write (%d bytes)\n", count); + if(acquire_sem(ok_to_write)==B_NO_ERROR) + { + memcpy(&streambuf, buffer, count); + + if (au_vol != 100) { // Handle volume scaling here + short *b=(short *)&streambuf; + for (int i=0; i < count/2; i++) { + int v=((int)b[i]*au_vol)/100; + b[i]=(v>32767) ? 32767 : ((v<-32768) ? -32768 : v); + } + } + + bytes_in_streambuf = count; + readbase = &streambuf[0]; + + release_sem(ok_to_read); + } + return 0; +} + |