5e58212dacee5daacad0209805ef2591684f9855
[paraslash.git] / amp_filter.c
1 /*
2 * Copyright (C) 2009 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file amp_filter.c Paraslash's amplify filter. */
8
9 #include <regex.h>
10 #include <stdbool.h>
11
12 #include "para.h"
13 #include "amp_filter.cmdline.h"
14 #include "list.h"
15 #include "sched.h"
16 #include "ggo.h"
17 #include "buffer_tree.h"
18 #include "filter.h"
19 #include "string.h"
20 #include "error.h"
21
22 /** The size of the output data buffer. */
23 #define AMP_CHUNK_SIZE 40960
24
25 extern char *stat_item_values[NUM_STAT_ITEMS];
26
27 /** Data specific to the amplify filter. */
28 struct private_amp_data {
29 /** Points to the configuration data for this instance of this filter. */
30 struct amp_filter_args_info *conf;
31 /** Amplification factor. */
32 unsigned amp;
33 };
34
35 static void amp_close(struct filter_node *fn)
36 {
37 free(fn->private_data);
38 free(fn->buf);
39 }
40
41 static int amp_parse_config(int argc, char **argv, void **config)
42 {
43 struct amp_filter_args_info *amp_conf = para_calloc(sizeof(*amp_conf));
44 int ret = -E_AMP_SYNTAX;
45
46 if (amp_cmdline_parser(argc, argv, amp_conf))
47 goto err;
48 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
49 if (amp_conf->amp_arg < 0)
50 goto err;
51 *config = amp_conf;
52 return 1;
53 err:
54 free(amp_conf);
55 return ret;
56 }
57
58 static void amp_open(struct filter_node *fn)
59 {
60 struct private_amp_data *pad = para_calloc(sizeof(*pad));
61
62 pad->conf = fn->conf;
63 fn->private_data = pad;
64 fn->min_iqs = 2;
65 if (!pad->conf->amp_given && stat_item_values[SI_AMPLIFICATION])
66 sscanf(stat_item_values[SI_AMPLIFICATION], "%u", &pad->amp);
67 else
68 pad->amp = pad->conf->amp_arg;
69 fn->bufsize = AMP_CHUNK_SIZE;
70 fn->buf = para_malloc(fn->bufsize);
71 PARA_NOTICE_LOG("amplification: %u (scaling factor: %1.2f)\n",
72 pad->amp, pad->amp / 64.0 + 1.0);
73 }
74
75 static void amp_post_select(__a_unused struct sched *s, struct task *t)
76 {
77 struct filter_node *fn = container_of(t, struct filter_node, task);
78 struct private_amp_data *pad = fn->private_data;
79 struct btr_node *btrn = fn->btrn;
80 int ret, factor = 64 + pad->amp;
81 size_t i, in_bytes, len;
82 int16_t *in, *out;
83 bool inplace = btr_inplace_ok(btrn);
84
85 if (pad->amp == 0) { /* no amplification */
86 t->error = -E_AMP_ZERO_AMP;
87 btr_splice_out_node(btrn);
88 return;
89 }
90 next_buffer:
91 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
92 if (ret < 0)
93 goto err;
94 if (ret == 0)
95 return;
96 btr_merge(btrn, fn->min_iqs);
97 in_bytes = btr_next_buffer(btrn, (char **)&in);
98 len = in_bytes / 2;
99 if (len == 0) { /* eof and in_bytes == 1 */
100 ret = -E_AMP_EOF;
101 goto err;
102 }
103
104 if (inplace)
105 out = in;
106 else
107 out = para_malloc(len * 2);
108
109 for (i = 0; i < len; i++) {
110 int x = (in[i] * factor) >> 6;
111
112 out[i] = x;
113 if (out[i] != x) /* overflow, clip */
114 out[i] = (x >= 0)? 32767 : -32768;
115 }
116
117 if (inplace)
118 btr_pushdown_one(btrn);
119 else {
120 btr_consume(btrn, len * 2);
121 btr_add_output((char *)out, len * 2, btrn);
122 }
123 t->error = 0;
124 goto next_buffer;
125 err:
126 assert(ret < 0);
127 t->error = ret;
128 btr_remove_node(btrn);
129 }
130
131 static void amp_free_config(void *conf)
132 {
133 amp_cmdline_parser_free(conf);
134 }
135
136 /**
137 * The init function of the amplify filter.
138 *
139 * \param f Pointer to the struct to initialize.
140 */
141 void amp_filter_init(struct filter *f)
142 {
143 struct amp_filter_args_info dummy;
144
145 amp_cmdline_parser_init(&dummy);
146 f->open = amp_open;
147 f->close = amp_close;
148 f->pre_select = generic_filter_pre_select;
149 f->post_select = amp_post_select;
150 f->parse_config = amp_parse_config;
151 f->free_config = amp_free_config;
152 f->help = (struct ggo_help) {
153 .short_help = amp_filter_args_info_help,
154 .detailed_help = amp_filter_args_info_detailed_help
155 };
156 }