]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * This file is part of the libsigrok project. | |
3 | * | |
4 | * Copyright (C) 2013 Bert Vermeulen <bert@biot.com> | |
5 | * | |
6 | * This program is free software: you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation, either version 3 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program. If not, see <http://www.gnu.org/licenses/>. | |
18 | */ | |
19 | ||
20 | #include <sys/types.h> | |
21 | #include <sys/stat.h> | |
22 | #include <unistd.h> | |
23 | #include <fcntl.h> | |
24 | #include <ctype.h> | |
25 | #include <string.h> | |
26 | #include "libsigrok.h" | |
27 | #include "libsigrok-internal.h" | |
28 | ||
29 | #define LOG_PREFIX "input/wav" | |
30 | ||
31 | /* How many bytes at a time to process and send to the session bus. */ | |
32 | #define CHUNK_SIZE 4096 | |
33 | /* Expect to find the "data" chunk within this offset from the start. */ | |
34 | #define MAX_DATA_CHUNK_OFFSET 256 | |
35 | ||
36 | #define WAVE_FORMAT_PCM 1 | |
37 | #define WAVE_FORMAT_IEEE_FLOAT 3 | |
38 | ||
39 | struct context { | |
40 | uint64_t samplerate; | |
41 | int samplesize; | |
42 | int num_channels; | |
43 | int unitsize; | |
44 | int fmt_code; | |
45 | }; | |
46 | ||
47 | static int get_wav_header(const char *filename, char *buf) | |
48 | { | |
49 | struct stat st; | |
50 | int fd, l; | |
51 | ||
52 | l = strlen(filename); | |
53 | if (l <= 4 || strcasecmp(filename + l - 4, ".wav")) | |
54 | return SR_ERR; | |
55 | ||
56 | if (stat(filename, &st) == -1) | |
57 | return SR_ERR; | |
58 | if (st.st_size <= 45) | |
59 | /* Minimum size of header + 1 8-bit mono PCM sample. */ | |
60 | return SR_ERR; | |
61 | ||
62 | if ((fd = open(filename, O_RDONLY)) == -1) | |
63 | return SR_ERR; | |
64 | ||
65 | l = read(fd, buf, 40); | |
66 | close(fd); | |
67 | if (l != 40) | |
68 | return SR_ERR; | |
69 | ||
70 | return SR_OK; | |
71 | } | |
72 | ||
73 | static int format_match(const char *filename) | |
74 | { | |
75 | char buf[40]; | |
76 | uint16_t fmt_code; | |
77 | ||
78 | if (get_wav_header(filename, buf) != SR_OK) | |
79 | return FALSE; | |
80 | ||
81 | if (strncmp(buf, "RIFF", 4)) | |
82 | return FALSE; | |
83 | if (strncmp(buf + 8, "WAVE", 4)) | |
84 | return FALSE; | |
85 | if (strncmp(buf + 12, "fmt ", 4)) | |
86 | return FALSE; | |
87 | fmt_code = GUINT16_FROM_LE(*(uint16_t *)(buf + 20)); | |
88 | if (fmt_code != WAVE_FORMAT_PCM | |
89 | && fmt_code != WAVE_FORMAT_IEEE_FLOAT) | |
90 | return FALSE; | |
91 | ||
92 | return TRUE; | |
93 | } | |
94 | ||
95 | static int init(struct sr_input *in, const char *filename) | |
96 | { | |
97 | struct sr_channel *ch; | |
98 | struct context *ctx; | |
99 | char buf[40], channelname[8]; | |
100 | int i; | |
101 | ||
102 | if (get_wav_header(filename, buf) != SR_OK) | |
103 | return SR_ERR; | |
104 | ||
105 | if (!(ctx = g_try_malloc0(sizeof(struct context)))) | |
106 | return SR_ERR_MALLOC; | |
107 | ||
108 | /* Create a virtual device. */ | |
109 | in->sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, NULL, NULL, NULL); | |
110 | in->sdi->priv = ctx; | |
111 | ||
112 | ctx->fmt_code = GUINT16_FROM_LE(*(uint16_t *)(buf + 20)); | |
113 | ctx->samplerate = GUINT32_FROM_LE(*(uint32_t *)(buf + 24)); | |
114 | ctx->samplesize = GUINT16_FROM_LE(*(uint16_t *)(buf + 32)); | |
115 | ctx->num_channels = GUINT16_FROM_LE(*(uint16_t *)(buf + 22)); | |
116 | ctx->unitsize = ctx->samplesize / ctx->num_channels; | |
117 | ||
118 | if (ctx->fmt_code == WAVE_FORMAT_PCM) { | |
119 | if (ctx->samplesize != 1 && ctx->samplesize != 2 | |
120 | && ctx->samplesize != 4) { | |
121 | sr_err("only 8, 16 or 32 bits per sample supported."); | |
122 | return SR_ERR; | |
123 | } | |
124 | } else { | |
125 | /* WAVE_FORMAT_IEEE_FLOAT */ | |
126 | if (ctx->samplesize / ctx->num_channels != 4) { | |
127 | sr_err("only 32-bit floats supported."); | |
128 | return SR_ERR; | |
129 | } | |
130 | } | |
131 | ||
132 | for (i = 0; i < ctx->num_channels; i++) { | |
133 | snprintf(channelname, 8, "CH%d", i + 1); | |
134 | ch = sr_channel_new(i, SR_CHANNEL_ANALOG, TRUE, channelname); | |
135 | in->sdi->channels = g_slist_append(in->sdi->channels, ch); | |
136 | } | |
137 | ||
138 | return SR_OK; | |
139 | } | |
140 | ||
141 | static int find_data_chunk(uint8_t *buf, int initial_offset) | |
142 | { | |
143 | int offset, i; | |
144 | ||
145 | offset = initial_offset; | |
146 | while(offset < MAX_DATA_CHUNK_OFFSET) { | |
147 | if (!memcmp(buf + offset, "data", 4)) | |
148 | /* Skip into the samples. */ | |
149 | return offset + 8; | |
150 | for (i = 0; i < 4; i++) { | |
151 | if (!isalpha(buf[offset + i]) | |
152 | && !isascii(buf[offset + i]) | |
153 | && !isblank(buf[offset + i])) | |
154 | /* Doesn't look like a chunk ID. */ | |
155 | return -1; | |
156 | } | |
157 | /* Skip past this chunk. */ | |
158 | offset += 8 + GUINT32_FROM_LE(*(uint32_t *)(buf + offset + 4)); | |
159 | } | |
160 | ||
161 | return offset; | |
162 | } | |
163 | ||
164 | static int loadfile(struct sr_input *in, const char *filename) | |
165 | { | |
166 | struct sr_datafeed_packet packet; | |
167 | struct sr_datafeed_meta meta; | |
168 | struct sr_datafeed_analog analog; | |
169 | struct sr_config *src; | |
170 | struct context *ctx; | |
171 | float fdata[CHUNK_SIZE]; | |
172 | uint64_t sample; | |
173 | int offset, chunk_samples, samplenum, fd, l, i; | |
174 | uint8_t buf[CHUNK_SIZE], *s, *d; | |
175 | ||
176 | ctx = in->sdi->priv; | |
177 | ||
178 | /* Send header packet to the session bus. */ | |
179 | std_session_send_df_header(in->sdi, LOG_PREFIX); | |
180 | ||
181 | /* Send the samplerate. */ | |
182 | packet.type = SR_DF_META; | |
183 | packet.payload = &meta; | |
184 | src = sr_config_new(SR_CONF_SAMPLERATE, | |
185 | g_variant_new_uint64(ctx->samplerate)); | |
186 | meta.config = g_slist_append(NULL, src); | |
187 | sr_session_send(in->sdi, &packet); | |
188 | sr_config_free(src); | |
189 | ||
190 | if ((fd = open(filename, O_RDONLY)) == -1) | |
191 | return SR_ERR; | |
192 | if (read(fd, buf, MAX_DATA_CHUNK_OFFSET) < MAX_DATA_CHUNK_OFFSET) | |
193 | return -1; | |
194 | ||
195 | /* Skip past size of 'fmt ' chunk. */ | |
196 | i = 20 + GUINT32_FROM_LE(*(uint32_t *)(buf + 16)); | |
197 | offset = find_data_chunk(buf, i); | |
198 | if (offset < 0) { | |
199 | sr_err("Couldn't find data chunk."); | |
200 | return SR_ERR; | |
201 | } | |
202 | if (lseek(fd, offset, SEEK_SET) == -1) | |
203 | return SR_ERR; | |
204 | ||
205 | memset(fdata, 0, CHUNK_SIZE); | |
206 | while (TRUE) { | |
207 | if ((l = read(fd, buf, CHUNK_SIZE)) < 1) | |
208 | break; | |
209 | chunk_samples = l / ctx->num_channels / ctx->unitsize; | |
210 | s = buf; | |
211 | d = (uint8_t *)fdata; | |
212 | for (samplenum = 0; samplenum < chunk_samples * ctx->num_channels; samplenum++) { | |
213 | if (ctx->fmt_code == WAVE_FORMAT_PCM) { | |
214 | sample = 0; | |
215 | memcpy(&sample, s, ctx->unitsize); | |
216 | switch (ctx->samplesize) { | |
217 | case 1: | |
218 | /* 8-bit PCM samples are unsigned. */ | |
219 | fdata[samplenum] = (uint8_t)sample / 255.0; | |
220 | break; | |
221 | case 2: | |
222 | fdata[samplenum] = GINT16_FROM_LE(sample) / 32767.0; | |
223 | break; | |
224 | case 4: | |
225 | fdata[samplenum] = GINT32_FROM_LE(sample) / 65535.0; | |
226 | break; | |
227 | } | |
228 | } else { | |
229 | /* BINARY32 float */ | |
230 | #ifdef WORDS_BIGENDIAN | |
231 | for (i = 0; i < ctx->unitsize; i++) | |
232 | d[i] = s[ctx->unitsize - i]; | |
233 | #else | |
234 | memcpy(d, s, ctx->unitsize); | |
235 | #endif | |
236 | } | |
237 | s += ctx->unitsize; | |
238 | d += ctx->unitsize; | |
239 | ||
240 | } | |
241 | packet.type = SR_DF_ANALOG; | |
242 | packet.payload = &analog; | |
243 | analog.channels = in->sdi->channels; | |
244 | analog.num_samples = chunk_samples; | |
245 | analog.mq = 0; | |
246 | analog.unit = 0; | |
247 | analog.data = fdata; | |
248 | sr_session_send(in->sdi, &packet); | |
249 | } | |
250 | ||
251 | close(fd); | |
252 | packet.type = SR_DF_END; | |
253 | sr_session_send(in->sdi, &packet); | |
254 | ||
255 | return SR_OK; | |
256 | } | |
257 | ||
258 | ||
259 | SR_PRIV struct sr_input_format input_wav = { | |
260 | .id = "wav", | |
261 | .description = "WAV file", | |
262 | .format_match = format_match, | |
263 | .init = init, | |
264 | .loadfile = loadfile, | |
265 | }; | |
266 |