2 * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file wav_filter.c A filter that inserts a wave header. */
17 #include "buffer_tree.h"
20 #include "portable_io.h"
22 /** size of the output buffer */
23 #define WAV_OUTBUF_SIZE 81920
24 /** a wav header is always 44 bytes */
25 #define WAV_HEADER_LEN 44
26 /** always write 16 bit header */
29 static void make_wav_header(unsigned int channels, unsigned int samplerate,
33 unsigned int size = 0x7fffffff;
34 int bytespersec = channels * samplerate * BITS / 8;
35 int align = channels * BITS / 8;
37 PARA_DEBUG_LOG("writing wave header: %d channels, %d KHz\n", channels, samplerate);
38 memset(headbuf, 0, WAV_HEADER_LEN);
39 memcpy(headbuf, "RIFF", 4);
40 write_u32(headbuf + 4, size - 8);
41 memcpy(headbuf + 8, "WAVE", 4);
42 memcpy(headbuf + 12, "fmt ", 4);
43 write_u32(headbuf + 16, 16); /* 16 + extra format bytes (zero) */
44 write_u16(headbuf + 20, 1); /* format (1 == PCM/uncompressed) */
45 write_u16(headbuf + 22, channels);
46 write_u32(headbuf + 24, samplerate);
47 write_u32(headbuf + 28, bytespersec);
48 write_u16(headbuf + 32, align); /* number of bytes per sample slice */
49 write_u16(headbuf + 34, BITS); /* significant bits per sample */
50 memcpy(headbuf + 36, "data", 4); /* chunk ID */
51 write_u32(headbuf + 40, size - 44); /* chunk size */
54 static ssize_t wav_convert(char *inbuf, size_t len, struct filter_node *fn)
57 int *bof = fn->private_data;
62 if (!fn->fc->channels || !fn->fc->samplerate) {
63 PARA_ERROR_LOG("%s\n", para_strerror(E_WAV_BAD_FC));
66 make_wav_header(fn->fc->channels, fn->fc->samplerate, fn->buf);
67 fn->loaded = WAV_HEADER_LEN;
71 copy = PARA_MIN(len, fn->bufsize - fn->loaded);
72 memmove(fn->buf + fn->loaded, inbuf, copy);
74 // PARA_DEBUG_LOG("len = %d, copy = %d\n", len, copy);
78 static void wav_close(struct filter_node *fn)
82 free(fn->private_data);
83 fn->private_data = NULL;
86 static void wav_open(struct filter_node *fn)
90 fn->bufsize = WAV_OUTBUF_SIZE;
91 fn->buf = para_malloc(fn->bufsize);
92 fn->private_data = para_malloc(sizeof(int));
93 bof = fn->private_data;
96 PARA_INFO_LOG("wav filter node: %p, output buffer: %p, loaded: %zd\n",
97 fn, fn->buf, fn->loaded);
100 static void wav_pre_select(struct sched *s, struct task *t)
102 struct filter_node *fn = container_of(t, struct filter_node, task);
103 size_t iqs = btr_get_input_queue_size(fn->btrn);
108 s->timeout.tv_sec = 0;
109 s->timeout.tv_usec = 1;
112 static void wav_post_select(__a_unused struct sched *s, struct task *t)
114 struct filter_node *fn = container_of(t, struct filter_node, task);
115 struct btr_node *btrn = fn->btrn;
116 size_t iqs = btr_get_input_queue_size(btrn);
125 if (btr_no_parent(btrn))
129 ret = btr_exec_up(btrn, "samplerate", &buf);
134 ret = para_atoi32(buf, &rate);
138 ret = btr_exec_up(btrn, "channels", &buf);
143 ret = para_atoi32(buf, &ch);
147 header = para_malloc(WAV_HEADER_LEN);
148 make_wav_header(ch, rate, header);
149 btr_add_output(header, WAV_HEADER_LEN, btrn);
150 ret = -E_WAV_SUCCESS;
153 if (ret == -E_WAV_SUCCESS)
154 btr_splice_out_node(btrn);
156 btr_remove_node(btrn);
157 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
162 * the init function of the wav filter
164 * \param f struct to initialize
166 void wav_filter_init(struct filter *f)
168 f->convert = wav_convert;
169 f->close = wav_close;
171 f->pre_select = wav_pre_select;
172 f->post_select = wav_post_select;