2 ** Copyright (C) 2003-2009 Erik de Castro Lopo <erikd@mega-nerd.com>
4 ** This program is free software; you can redistribute it and/or modify
5 ** it under the terms of the GNU Lesser General Public License as published by
6 ** the Free Software Foundation; either version 2.1 of the License, or
7 ** (at your option) any later version.
9 ** This program is distributed in the hope that it will be useful,
10 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
11 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 ** GNU Lesser General Public License for more details.
14 ** You should have received a copy of the GNU Lesser General Public License
15 ** along with this program; if not, write to the Free Software
16 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 /*============================================================================
28 ** Rule number 1 is to only apply dither when going from a larger bitwidth
29 ** to a smaller bitwidth. This can happen on both read and write.
31 ** Need to apply dither on all conversions marked X below.
36 ** | short int float double
37 ** --------+-----------------------------------------------
39 ** u 16 bit | none X X X
40 ** t 24 bit | none X X X
41 ** p 32 bit | none none X X
42 ** u float | none none none none
43 ** t double | none none none none
48 ** O | 8 bit 16 bit 24 bit 32 bit float double
49 ** u --------+-------------------------------------------------
50 ** t short | none none X X X X
51 ** p int | none none none X X X
52 ** u float | none none none none none none
53 ** t double | none none none none none none
56 #define SFE_DITHER_BAD_PTR 666
57 #define SFE_DITHER_BAD_TYPE 667
60 { int read_short_dither_bits, read_int_dither_bits ;
61 int write_short_dither_bits, write_int_dither_bits ;
62 double read_float_dither_scale, read_double_dither_bits ;
63 double write_float_dither_scale, write_double_dither_bits ;
65 sf_count_t (*read_short) (SF_PRIVATE *psf, short *ptr, sf_count_t len) ;
66 sf_count_t (*read_int) (SF_PRIVATE *psf, int *ptr, sf_count_t len) ;
67 sf_count_t (*read_float) (SF_PRIVATE *psf, float *ptr, sf_count_t len) ;
68 sf_count_t (*read_double) (SF_PRIVATE *psf, double *ptr, sf_count_t len) ;
70 sf_count_t (*write_short) (SF_PRIVATE *psf, const short *ptr, sf_count_t len) ;
71 sf_count_t (*write_int) (SF_PRIVATE *psf, const int *ptr, sf_count_t len) ;
72 sf_count_t (*write_float) (SF_PRIVATE *psf, const float *ptr, sf_count_t len) ;
73 sf_count_t (*write_double) (SF_PRIVATE *psf, const double *ptr, sf_count_t len) ;
75 double buffer [SF_BUFFER_LEN / sizeof (double)] ;
78 static sf_count_t dither_read_short (SF_PRIVATE *psf, short *ptr, sf_count_t len) ;
79 static sf_count_t dither_read_int (SF_PRIVATE *psf, int *ptr, sf_count_t len) ;
81 static sf_count_t dither_write_short (SF_PRIVATE *psf, const short *ptr, sf_count_t len) ;
82 static sf_count_t dither_write_int (SF_PRIVATE *psf, const int *ptr, sf_count_t len) ;
83 static sf_count_t dither_write_float (SF_PRIVATE *psf, const float *ptr, sf_count_t len) ;
84 static sf_count_t dither_write_double (SF_PRIVATE *psf, const double *ptr, sf_count_t len) ;
87 dither_init (SF_PRIVATE *psf, int mode)
88 { DITHER_DATA *pdither ;
90 pdither = psf->dither ; /* This may be NULL. */
92 /* Turn off dither on read. */
93 if (mode == SFM_READ && psf->read_dither.type == SFD_NO_DITHER)
94 { if (pdither == NULL)
95 return 0 ; /* Dither is already off, so just return. */
97 if (pdither->read_short)
98 psf->read_short = pdither->read_short ;
99 if (pdither->read_int)
100 psf->read_int = pdither->read_int ;
101 if (pdither->read_float)
102 psf->read_float = pdither->read_float ;
103 if (pdither->read_double)
104 psf->read_double = pdither->read_double ;
108 /* Turn off dither on write. */
109 if (mode == SFM_WRITE && psf->write_dither.type == SFD_NO_DITHER)
110 { if (pdither == NULL)
111 return 0 ; /* Dither is already off, so just return. */
113 if (pdither->write_short)
114 psf->write_short = pdither->write_short ;
115 if (pdither->write_int)
116 psf->write_int = pdither->write_int ;
117 if (pdither->write_float)
118 psf->write_float = pdither->write_float ;
119 if (pdither->write_double)
120 psf->write_double = pdither->write_double ;
124 /* Turn on dither on read if asked. */
125 if (mode == SFM_READ && psf->read_dither.type != 0)
126 { if (pdither == NULL)
127 pdither = psf->dither = calloc (1, sizeof (DITHER_DATA)) ;
129 return SFE_MALLOC_FAILED ;
131 switch (SF_CODEC (psf->sf.format))
132 { case SF_FORMAT_DOUBLE :
133 case SF_FORMAT_FLOAT :
134 pdither->read_int = psf->read_int ;
135 psf->read_int = dither_read_int ;
138 case SF_FORMAT_PCM_32 :
139 case SF_FORMAT_PCM_24 :
140 case SF_FORMAT_PCM_16 :
141 case SF_FORMAT_PCM_S8 :
142 case SF_FORMAT_PCM_U8 :
143 pdither->read_short = psf->read_short ;
144 psf->read_short = dither_read_short ;
151 /* Turn on dither on write if asked. */
152 if (mode == SFM_WRITE && psf->write_dither.type != 0)
153 { if (pdither == NULL)
154 pdither = psf->dither = calloc (1, sizeof (DITHER_DATA)) ;
156 return SFE_MALLOC_FAILED ;
158 switch (SF_CODEC (psf->sf.format))
159 { case SF_FORMAT_DOUBLE :
160 case SF_FORMAT_FLOAT :
161 pdither->write_int = psf->write_int ;
162 psf->write_int = dither_write_int ;
165 case SF_FORMAT_PCM_32 :
166 case SF_FORMAT_PCM_24 :
167 case SF_FORMAT_PCM_16 :
168 case SF_FORMAT_PCM_S8 :
169 case SF_FORMAT_PCM_U8 :
175 pdither->write_short = psf->write_short ;
176 psf->write_short = dither_write_short ;
178 pdither->write_int = psf->write_int ;
179 psf->write_int = dither_write_int ;
181 pdither->write_float = psf->write_float ;
182 psf->write_float = dither_write_float ;
184 pdither->write_double = psf->write_double ;
185 psf->write_double = dither_write_double ;
191 /*==============================================================================
194 static void dither_short (const short *in, short *out, int frames, int channels) ;
195 static void dither_int (const int *in, int *out, int frames, int channels) ;
197 static void dither_float (const float *in, float *out, int frames, int channels) ;
198 static void dither_double (const double *in, double *out, int frames, int channels) ;
201 dither_read_short (SF_PRIVATE * UNUSED (psf), short * UNUSED (ptr), sf_count_t len)
204 } /* dither_read_short */
207 dither_read_int (SF_PRIVATE * UNUSED (psf), int * UNUSED (ptr), sf_count_t len)
210 } /* dither_read_int */
212 /*------------------------------------------------------------------------------
216 dither_write_short (SF_PRIVATE *psf, const short *ptr, sf_count_t len)
217 { DITHER_DATA *pdither ;
218 int bufferlen, writecount, thiswrite ;
219 sf_count_t total = 0 ;
221 if ((pdither = psf->dither) == NULL)
222 { psf->error = SFE_DITHER_BAD_PTR ;
226 switch (SF_CODEC (psf->sf.format))
227 { case SF_FORMAT_PCM_S8 :
228 case SF_FORMAT_PCM_U8 :
229 case SF_FORMAT_DPCM_8 :
233 return pdither->write_short (psf, ptr, len) ;
236 bufferlen = sizeof (pdither->buffer) / sizeof (short) ;
239 { writecount = (len >= bufferlen) ? bufferlen : (int) len ;
240 writecount /= psf->sf.channels ;
241 writecount *= psf->sf.channels ;
243 dither_short (ptr, (short*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ;
245 thiswrite = pdither->write_short (psf, (short*) pdither->buffer, writecount) ;
248 if (thiswrite < writecount)
253 } /* dither_write_short */
256 dither_write_int (SF_PRIVATE *psf, const int *ptr, sf_count_t len)
257 { DITHER_DATA *pdither ;
258 int bufferlen, writecount, thiswrite ;
259 sf_count_t total = 0 ;
261 if ((pdither = psf->dither) == NULL)
262 { psf->error = SFE_DITHER_BAD_PTR ;
266 switch (SF_CODEC (psf->sf.format))
267 { case SF_FORMAT_PCM_S8 :
268 case SF_FORMAT_PCM_U8 :
269 case SF_FORMAT_PCM_16 :
270 case SF_FORMAT_PCM_24 :
273 case SF_FORMAT_DPCM_8 :
274 case SF_FORMAT_DPCM_16 :
278 return pdither->write_int (psf, ptr, len) ;
282 bufferlen = sizeof (pdither->buffer) / sizeof (int) ;
285 { writecount = (len >= bufferlen) ? bufferlen : (int) len ;
286 writecount /= psf->sf.channels ;
287 writecount *= psf->sf.channels ;
289 dither_int (ptr, (int*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ;
291 thiswrite = pdither->write_int (psf, (int*) pdither->buffer, writecount) ;
294 if (thiswrite < writecount)
299 } /* dither_write_int */
302 dither_write_float (SF_PRIVATE *psf, const float *ptr, sf_count_t len)
303 { DITHER_DATA *pdither ;
304 int bufferlen, writecount, thiswrite ;
305 sf_count_t total = 0 ;
307 if ((pdither = psf->dither) == NULL)
308 { psf->error = SFE_DITHER_BAD_PTR ;
312 switch (SF_CODEC (psf->sf.format))
313 { case SF_FORMAT_PCM_S8 :
314 case SF_FORMAT_PCM_U8 :
315 case SF_FORMAT_PCM_16 :
316 case SF_FORMAT_PCM_24 :
319 case SF_FORMAT_DPCM_8 :
320 case SF_FORMAT_DPCM_16 :
324 return pdither->write_float (psf, ptr, len) ;
327 bufferlen = sizeof (pdither->buffer) / sizeof (float) ;
330 { writecount = (len >= bufferlen) ? bufferlen : (float) len ;
331 writecount /= psf->sf.channels ;
332 writecount *= psf->sf.channels ;
334 dither_float (ptr, (float*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ;
336 thiswrite = pdither->write_float (psf, (float*) pdither->buffer, writecount) ;
339 if (thiswrite < writecount)
344 } /* dither_write_float */
347 dither_write_double (SF_PRIVATE *psf, const double *ptr, sf_count_t len)
348 { DITHER_DATA *pdither ;
349 int bufferlen, writecount, thiswrite ;
350 sf_count_t total = 0 ;
352 if ((pdither = psf->dither) == NULL)
353 { psf->error = SFE_DITHER_BAD_PTR ;
357 switch (SF_CODEC (psf->sf.format))
358 { case SF_FORMAT_PCM_S8 :
359 case SF_FORMAT_PCM_U8 :
360 case SF_FORMAT_PCM_16 :
361 case SF_FORMAT_PCM_24 :
364 case SF_FORMAT_DPCM_8 :
365 case SF_FORMAT_DPCM_16 :
369 return pdither->write_double (psf, ptr, len) ;
373 bufferlen = sizeof (pdither->buffer) / sizeof (double) ;
376 { writecount = (len >= bufferlen) ? bufferlen : (double) len ;
377 writecount /= psf->sf.channels ;
378 writecount *= psf->sf.channels ;
380 dither_double (ptr, (double*) pdither->buffer, writecount / psf->sf.channels, psf->sf.channels) ;
382 thiswrite = pdither->write_double (psf, (double*) pdither->buffer, writecount) ;
385 if (thiswrite < writecount)
390 } /* dither_write_double */
392 /*==============================================================================
396 dither_short (const short *in, short *out, int frames, int channels)
399 for (ch = 0 ; ch < channels ; ch++)
400 for (k = ch ; k < channels * frames ; k += channels)
406 dither_int (const int *in, int *out, int frames, int channels)
409 for (ch = 0 ; ch < channels ; ch++)
410 for (k = ch ; k < channels * frames ; k += channels)
416 dither_float (const float *in, float *out, int frames, int channels)
419 for (ch = 0 ; ch < channels ; ch++)
420 for (k = ch ; k < channels * frames ; k += channels)
426 dither_double (const double *in, double *out, int frames, int channels)
429 for (ch = 0 ; ch < channels ; ch++)
430 for (k = ch ; k < channels * frames ; k += channels)
433 } /* dither_double */
435 /*==============================================================================
440 ** Not made public because this (maybe) requires storage of state information.
442 ** Also maybe need separate state info for each channel!!!!
446 DO_NOT_USE_sf_dither_short (const SF_DITHER_INFO *dither, const short *in, short *out, int frames, int channels)
450 return SFE_DITHER_BAD_PTR ;
452 switch (dither->type & SFD_TYPEMASK)
454 case SFD_TRIANGULAR_PDF :
455 for (ch = 0 ; ch < channels ; ch++)
456 for (k = ch ; k < channels * frames ; k += channels)
461 return SFE_DITHER_BAD_TYPE ;
465 } /* DO_NOT_USE_sf_dither_short */
468 DO_NOT_USE_sf_dither_int (const SF_DITHER_INFO *dither, const int *in, int *out, int frames, int channels)
472 return SFE_DITHER_BAD_PTR ;
474 switch (dither->type & SFD_TYPEMASK)
476 case SFD_TRIANGULAR_PDF :
477 for (ch = 0 ; ch < channels ; ch++)
478 for (k = ch ; k < channels * frames ; k += channels)
483 return SFE_DITHER_BAD_TYPE ;
487 } /* DO_NOT_USE_sf_dither_int */
490 DO_NOT_USE_sf_dither_float (const SF_DITHER_INFO *dither, const float *in, float *out, int frames, int channels)
494 return SFE_DITHER_BAD_PTR ;
496 switch (dither->type & SFD_TYPEMASK)
498 case SFD_TRIANGULAR_PDF :
499 for (ch = 0 ; ch < channels ; ch++)
500 for (k = ch ; k < channels * frames ; k += channels)
505 return SFE_DITHER_BAD_TYPE ;
509 } /* DO_NOT_USE_sf_dither_float */
512 DO_NOT_USE_sf_dither_double (const SF_DITHER_INFO *dither, const double *in, double *out, int frames, int channels)
516 return SFE_DITHER_BAD_PTR ;
518 switch (dither->type & SFD_TYPEMASK)
520 case SFD_TRIANGULAR_PDF :
521 for (ch = 0 ; ch < channels ; ch++)
522 for (k = ch ; k < channels * frames ; k += channels)
527 return SFE_DITHER_BAD_TYPE ;
531 } /* DO_NOT_USE_sf_dither_double */