mirror of
https://github.com/tildearrow/furnace.git
synced 2024-12-03 09:47:26 +00:00
78 lines
2.8 KiB
C
78 lines
2.8 KiB
C
/** \file
|
|
Sample buffer that resamples from input clock rate to output sample rate */
|
|
|
|
/* blip_buf $vers */
|
|
#ifndef BLIP_BUF_H
|
|
#define BLIP_BUF_H
|
|
|
|
// MODIFIED by tildearrow:
|
|
// - add option to disable high-pass filter
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/** First parameter of most functions is blip_t*, or const blip_t* if nothing
|
|
is changed. */
|
|
typedef struct blip_t blip_t;
|
|
|
|
/** Creates new buffer that can hold at most sample_count samples. Sets rates
|
|
so that there are blip_max_ratio clocks per sample. Returns pointer to new
|
|
buffer, or NULL if insufficient memory. */
|
|
blip_t* blip_new( int sample_count );
|
|
|
|
/** (tildearrow) sets whether to enable high-pass filter. */
|
|
void blip_set_dc( blip_t*, unsigned char enable );
|
|
|
|
/** Sets approximate input clock rate and output sample rate. For every
|
|
clock_rate input clocks, approximately sample_rate samples are generated. */
|
|
void blip_set_rates( blip_t*, double clock_rate, double sample_rate );
|
|
|
|
enum { /** Maximum clock_rate/sample_rate ratio. For a given sample_rate,
|
|
clock_rate must not be greater than sample_rate*blip_max_ratio. */
|
|
blip_max_ratio = 1 << 20 };
|
|
|
|
/** Clears entire buffer. Afterwards, blip_samples_avail() == 0. */
|
|
void blip_clear( blip_t* );
|
|
|
|
/** Adds positive/negative delta into buffer at specified clock time. */
|
|
void blip_add_delta( blip_t*, unsigned int clock_time, int delta );
|
|
|
|
/** Same as blip_add_delta(), but uses faster, lower-quality synthesis. */
|
|
void blip_add_delta_fast( blip_t*, unsigned int clock_time, int delta );
|
|
|
|
/** Length of time frame, in clocks, needed to make sample_count additional
|
|
samples available. */
|
|
int blip_clocks_needed( const blip_t*, int sample_count );
|
|
|
|
enum { /** Maximum number of samples that can be generated from one time frame. */
|
|
blip_max_frame = 4000 };
|
|
|
|
/** Makes input clocks before clock_duration available for reading as output
|
|
samples. Also begins new time frame at clock_duration, so that clock time 0 in
|
|
the new time frame specifies the same clock as clock_duration in the old time
|
|
frame specified. Deltas can have been added slightly past clock_duration (up to
|
|
however many clocks there are in two output samples). */
|
|
void blip_end_frame( blip_t*, unsigned int clock_duration );
|
|
|
|
/** Number of buffered samples available for reading. */
|
|
int blip_samples_avail( const blip_t* );
|
|
|
|
/** Reads and removes at most 'count' samples and writes them to 'out'. If
|
|
'stereo' is true, writes output to every other element of 'out', allowing easy
|
|
interleaving of two buffers into a stereo sample stream. Outputs 16-bit signed
|
|
samples. Returns number of samples actually read. */
|
|
int blip_read_samples( blip_t*, short out [], int count, int stereo );
|
|
|
|
/** Frees buffer. No effect if NULL is passed. */
|
|
void blip_delete( blip_t* );
|
|
|
|
|
|
/* Deprecated */
|
|
typedef blip_t blip_buffer_t;
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif
|