New codename for 0.4.
[paraslash.git] / wav_filter.c
1 /*
2 * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file wav_filter.c A filter that inserts a wave header. */
8
9 #include "para.h"
10 #include "error.h"
11
12 #include "list.h"
13 #include "sched.h"
14 #include "ggo.h"
15 #include "filter.h"
16 #include "string.h"
17 #include "portable_io.h"
18
19 /** size of the output buffer */
20 #define WAV_OUTBUF_SIZE 81920
21 /** a wav header is always 44 bytes */
22 #define WAV_HEADER_LEN 44
23 /** always write 16 bit header */
24 #define BITS 16
25
26 static void make_wav_header(unsigned int channels, unsigned int samplerate,
27 struct filter_node *fn)
28 {
29
30 char *headbuf = fn->buf;
31 unsigned int size = 0x7fffffff;
32 int bytespersec = channels * samplerate * BITS / 8;
33 int align = channels * BITS / 8;
34
35 PARA_DEBUG_LOG("writing wave header: %d channels, %d KHz\n", channels, samplerate);
36 memset(headbuf, 0, WAV_HEADER_LEN);
37 memcpy(headbuf, "RIFF", 4);
38 write_u32(headbuf + 4, size - 8);
39 memcpy(headbuf + 8, "WAVE", 4);
40 memcpy(headbuf + 12, "fmt ", 4);
41 write_u32(headbuf + 16, 16); /* 16 + extra format bytes (zero) */
42 write_u16(headbuf + 20, 1); /* format (1 == PCM/uncompressed) */
43 write_u16(headbuf + 22, channels);
44 write_u32(headbuf + 24, samplerate);
45 write_u32(headbuf + 28, bytespersec);
46 write_u16(headbuf + 32, align); /* number of bytes per sample slice */
47 write_u16(headbuf + 34, BITS); /* significant bits per sample */
48 memcpy(headbuf + 36, "data", 4); /* chunk ID */
49 write_u32(headbuf + 40, size - 44); /* chunk size */
50 }
51
52 static ssize_t wav_convert(char *inbuf, size_t len, struct filter_node *fn)
53 {
54 size_t copy;
55 int *bof = fn->private_data;
56
57 if (*bof) {
58 if (!len)
59 return 0;
60 if (!fn->fc->channels || !fn->fc->samplerate) {
61 PARA_ERROR_LOG("%s\n", para_strerror(E_WAV_BAD_FC));
62 return -E_WAV_BAD_FC;
63 }
64 make_wav_header(fn->fc->channels, fn->fc->samplerate, fn);
65 fn->loaded = WAV_HEADER_LEN;
66 *bof = 0;
67 // return 0;
68 }
69 copy = PARA_MIN(len, fn->bufsize - fn->loaded);
70 memmove(fn->buf + fn->loaded, inbuf, copy);
71 fn->loaded += copy;
72 // PARA_DEBUG_LOG("len = %d, copy = %d\n", len, copy);
73 return copy;
74 }
75
76 static void wav_close(struct filter_node *fn)
77 {
78 free(fn->buf);
79 fn->buf = NULL;
80 free(fn->private_data);
81 fn->private_data = NULL;
82 }
83
84 static void wav_open(struct filter_node *fn)
85 {
86 int *bof;
87
88 fn->bufsize = WAV_OUTBUF_SIZE;
89 fn->buf = para_malloc(fn->bufsize);
90 fn->private_data = para_malloc(sizeof(int));
91 bof = fn->private_data;
92 fn->loaded = 0;
93 *bof = 1;
94 PARA_INFO_LOG("wav filter node: %p, output buffer: %p, loaded: %zd\n",
95 fn, fn->buf, fn->loaded);
96 }
97
98 /**
99 * the init function of the wav filter
100 *
101 * \param f struct to initialize
102 */
103 void wav_filter_init(struct filter *f)
104 {
105 f->convert = wav_convert;
106 f->close = wav_close;
107 f->open = wav_open;
108 }