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-rw-r--r--src/pcm_dither.c93
1 files changed, 0 insertions, 93 deletions
diff --git a/src/pcm_dither.c b/src/pcm_dither.c
deleted file mode 100644
index 4811946c..00000000
--- a/src/pcm_dither.c
+++ /dev/null
@@ -1,93 +0,0 @@
-/*
- * Copyright (C) 2003-2011 The Music Player Daemon Project
- * http://www.musicpd.org
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- */
-
-#include "config.h"
-#include "pcm_dither.h"
-#include "pcm_prng.h"
-
-static int16_t
-pcm_dither_sample_24_to_16(int32_t sample, struct pcm_dither *dither)
-{
- int32_t output, rnd;
-
- enum {
- from_bits = 24,
- to_bits = 16,
- scale_bits = from_bits - to_bits,
- round = 1 << (scale_bits - 1),
- mask = (1 << scale_bits) - 1,
- ONE = 1 << (from_bits - 1),
- MIN = -ONE,
- MAX = ONE - 1
- };
-
- sample += dither->error[0] - dither->error[1] + dither->error[2];
-
- dither->error[2] = dither->error[1];
- dither->error[1] = dither->error[0] / 2;
-
- /* round */
- output = sample + round;
-
- rnd = pcm_prng(dither->random);
- output += (rnd & mask) - (dither->random & mask);
-
- dither->random = rnd;
-
- /* clip */
- if (output > MAX) {
- output = MAX;
-
- if (sample > MAX)
- sample = MAX;
- } else if (output < MIN) {
- output = MIN;
-
- if (sample < MIN)
- sample = MIN;
- }
-
- output &= ~mask;
-
- dither->error[0] = sample - output;
-
- return (int16_t)(output >> scale_bits);
-}
-
-void
-pcm_dither_24_to_16(struct pcm_dither *dither,
- int16_t *dest, const int32_t *src, const int32_t *src_end)
-{
- while (src < src_end)
- *dest++ = pcm_dither_sample_24_to_16(*src++, dither);
-}
-
-static int16_t
-pcm_dither_sample_32_to_16(int32_t sample, struct pcm_dither *dither)
-{
- return pcm_dither_sample_24_to_16(sample >> 8, dither);
-}
-
-void
-pcm_dither_32_to_16(struct pcm_dither *dither,
- int16_t *dest, const int32_t *src, const int32_t *src_end)
-{
- while (src < src_end)
- *dest++ = pcm_dither_sample_32_to_16(*src++, dither);
-}