Introduce the new nonblock API.
[paraslash.git] / compress_filter.c
1 /*
2 * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file compress_filter.c Paraslash's dynamic audio range compressor. */
8
9 /*
10 * Uses ideas of AudioCompress, (C) 2002-2004 M. Hari Nezumi <magenta@trikuare.cx>
11 */
12
13 #include <regex.h>
14 #include <stdbool.h>
15
16 #include "para.h"
17 #include "compress_filter.cmdline.h"
18 #include "list.h"
19 #include "sched.h"
20 #include "ggo.h"
21 #include "buffer_tree.h"
22 #include "filter.h"
23 #include "string.h"
24 #include "error.h"
25
26 /** Data specific to the compress filter. */
27 struct private_compress_data {
28 /** The current multiplier. */
29 unsigned current_gain;
30 /** Points to the configuration data for this instance of the compress filter. */
31 struct compress_filter_args_info *conf;
32 /** Maximal admissible gain. */
33 unsigned max_gain;
34 /** Number of samples already seen. */
35 unsigned num_samples;
36 /** Absolute value of the maximal sample in the current block. */
37 int peak;
38 };
39
40 static void compress_close(struct filter_node *fn)
41 {
42 free(fn->private_data);
43 }
44
45 static void compress_post_select(__a_unused struct sched *s, struct task *t)
46 {
47 struct filter_node *fn = container_of(t, struct filter_node, task);
48 struct private_compress_data *pcd = fn->private_data;
49 struct btr_node *btrn = fn->btrn;
50 bool inplace = btr_inplace_ok(btrn);
51 int ret;
52 char *inbuf;
53 size_t length, i;
54 int16_t *ip, *op;
55 unsigned gain_shift = pcd->conf->inertia_arg + pcd->conf->damp_arg,
56 mask = (1 << pcd->conf->blocksize_arg) - 1;
57
58 //inplace = false;
59 next_buffer:
60 t->error = 0;
61 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
62 if (ret < 0)
63 goto err;
64 if (ret == 0)
65 return;
66 btr_merge(btrn, fn->min_iqs);
67 length = btr_next_buffer(btrn, &inbuf) & ~(size_t)1;
68 if (length == 0) { /* eof and 1 byte available */
69 ret = -E_COMPRESS_EOF;
70 goto err;
71 }
72 ip = (int16_t *)inbuf;
73 if (inplace)
74 op = ip;
75 else
76 op = para_malloc(length);
77 for (i = 0; i < length / 2; i++) {
78 /* be careful in that heat, my dear */
79 int sample = *ip++, adjusted_sample = (PARA_ABS(sample) *
80 pcd->current_gain) >> gain_shift;
81 if (adjusted_sample > 32767) { /* clip */
82 PARA_NOTICE_LOG("clip: sample: %d, adjusted sample: %d\n",
83 sample, adjusted_sample);
84 adjusted_sample = 32767;
85 pcd->current_gain = (3 * pcd->current_gain +
86 (1 << pcd->conf->inertia_arg)) / 4;
87 pcd->peak = 0;
88 } else
89 pcd->peak = PARA_MAX(pcd->peak, adjusted_sample);
90 op[i] = sample >= 0? adjusted_sample : -adjusted_sample;
91 if (++pcd->num_samples & mask)
92 continue;
93 // PARA_DEBUG_LOG("gain: %u, peak: %u\n", pcd->current_gain,
94 // pcd->peak);
95 if (pcd->peak < pcd->conf->target_level_arg) {
96 if (pcd->current_gain < pcd->max_gain)
97 pcd->current_gain++;
98 } else
99 pcd->current_gain = PARA_MAX(pcd->current_gain - 2,
100 1U << pcd->conf->inertia_arg);
101 pcd->peak = 0;
102 }
103 if (inplace)
104 btr_pushdown_one(btrn);
105 else {
106 btr_consume(btrn, length);
107 btr_add_output((char *)op, length, btrn);
108 }
109 goto next_buffer;
110 err:
111 assert(ret < 0);
112 t->error = ret;
113 btr_remove_node(btrn);
114 }
115
116 /** TODO: Add sanity checks */
117 static int compress_parse_config(int argc, char **argv, void **config)
118 {
119 int ret;
120 struct compress_filter_args_info *compress_conf
121 = para_calloc(sizeof(*compress_conf));
122
123 ret = -E_COMPRESS_SYNTAX;
124 if (compress_cmdline_parser(argc, argv, compress_conf))
125 goto err;
126 *config = compress_conf;
127 return 1;
128 err:
129 free(compress_conf);
130 return ret;
131 }
132
133 static void compress_open(struct filter_node *fn)
134 {
135 struct private_compress_data *pcd = para_calloc(
136 sizeof(struct private_compress_data));
137 pcd->conf = fn->conf;
138 fn->private_data = pcd;
139 fn->min_iqs = 2; /* 16 bit audio */
140 pcd->current_gain = 1 << pcd->conf->inertia_arg;
141 pcd->max_gain = 1 << (pcd->conf->inertia_arg + pcd->conf->aggressiveness_arg);
142 }
143
144 static void compress_free_config(void *conf)
145 {
146 compress_cmdline_parser_free(conf);
147 }
148
149 /**
150 * The init function of the compress filter.
151 *
152 * \param f Pointer to the struct to initialize.
153 */
154 void compress_filter_init(struct filter *f)
155 {
156 struct compress_filter_args_info dummy;
157
158 compress_cmdline_parser_init(&dummy);
159 f->open = compress_open;
160 f->close = compress_close;
161 f->pre_select = generic_filter_pre_select;
162 f->post_select = compress_post_select;
163 f->parse_config = compress_parse_config;
164 f->free_config = compress_free_config;
165 f->help = (struct ggo_help) {
166 .short_help = compress_filter_args_info_help,
167 .detailed_help = compress_filter_args_info_detailed_help
168 };
169 }