2 * Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file resample_filter.c A sample rate converter based on libsamplerate. */
10 #include <samplerate.h>
13 #include "filter_cmd.lsg.h"
18 #include "buffer_tree.h"
21 #include "check_wav.h"
23 #define U32_OPTVAL(_opt, _lpr) (FILTER_CMD_OPT_UINT32_VAL(RESAMPLE, _opt, _lpr))
24 #define OPT_GIVEN(_opt, _lpr) (FILTER_CMD_OPT_GIVEN(RESAMPLE, _opt, _lpr))
26 /* effective values, may differ from config arg */
27 struct resample_context {
29 int source_sample_rate;
32 struct check_wav_context *cwc;
35 static int resample_execute(struct btr_node *btrn, const char *cmd, char **result)
37 struct filter_node *fn = btr_context(btrn);
38 struct resample_context *ctx = fn->private_data;
39 uint32_t dsr = U32_OPTVAL(DEST_SAMPLE_RATE, fn->lpr);
40 return decoder_execute(cmd, dsr, ctx->channels, result);
43 static void resample_close(struct filter_node *fn)
45 struct resample_context *ctx = fn->private_data;
49 check_wav_shutdown(ctx->cwc);
51 src_delete(ctx->src_state);
53 fn->private_data = NULL;
56 static void resample_open(struct filter_node *fn)
58 struct resample_context *ctx = para_calloc(sizeof(*ctx));
59 struct btr_node *btrn = fn->btrn;
62 fn->private_data = ctx;
64 LLS_COPY_WAV_PARMS(&wp, LSG_FILTER_CMD_RESAMPLE, fn->lpr);
65 ctx->cwc = check_wav_init(btr_parent(btrn), btrn, &wp, NULL);
66 btr_log_tree(btr_parent(btr_parent(btrn)), LL_INFO);
69 static void resample_pre_select(struct sched *s, void *context)
71 struct filter_node *fn = context;
72 struct resample_context *ctx = fn->private_data;
73 int ret = btr_node_status(fn->btrn, fn->min_iqs, BTR_NT_INTERNAL);
76 return sched_min_delay(s);
77 check_wav_pre_select(s, ctx->cwc);
80 static int get_btr_val(const char *what, struct btr_node *btrn)
84 int ret = btr_exec_up(btr_parent(btrn), what, &buf);
87 PARA_NOTICE_LOG("btr exec for \"%s\" failed\n", what);
90 ret = para_atoi32(buf, &val);
92 return ret < 0? ret : val;
95 static int resample_set_params(struct filter_node *fn)
98 struct resample_context *ctx = fn->private_data;
99 struct btr_node *btrn = fn->btrn;
100 struct lls_parse_result *lpr = fn->lpr;
102 ctx->channels = U32_OPTVAL(CHANNELS, lpr);
103 if (!OPT_GIVEN(CHANNELS, lpr)) {
104 ret = get_btr_val("channels", btrn);
108 ctx->source_sample_rate = U32_OPTVAL(SAMPLE_RATE, lpr);
109 if (!OPT_GIVEN(SAMPLE_RATE, lpr)) {
110 ret = get_btr_val("sample_rate", btrn);
112 ctx->source_sample_rate = ret;
114 /* reject all sample formats except 16 bit signed, little endian */
115 ret = get_btr_val("sample_format", btrn);
116 if (ret >= 0 && ret != SF_S16_LE) {
117 const char * const sample_formats[] = {SAMPLE_FORMATS};
118 PARA_ERROR_LOG("unsupported sample format: %s\n",
119 sample_formats[ret]);
120 return -ERRNO_TO_PARA_ERROR(EINVAL);
122 ctx->ratio = U32_OPTVAL(DEST_SAMPLE_RATE, lpr)
123 / (float)ctx->source_sample_rate;
127 static int resample_init(struct filter_node *fn)
129 int ret, converter = *(int *)fn->conf;
130 struct resample_context *ctx = fn->private_data;
132 ret = resample_set_params(fn);
135 ctx->src_state = src_new(converter, U32_OPTVAL(CHANNELS, fn->lpr), &ret);
136 if (!ctx->src_state) {
137 PARA_ERROR_LOG("%s\n", src_strerror(ret));
138 return -E_LIBSAMPLERATE;
140 fn->min_iqs = 2 * ctx->channels;
144 /* returns number of input frames used */
145 static int resample_frames(int16_t *in, size_t num_frames, bool have_more,
146 struct resample_context *ctx, int16_t **result,
147 size_t *result_frames)
149 int ret, num_samples, out_samples;
153 data.src_ratio = ctx->ratio;
154 data.end_of_input = !have_more;
156 data.input_frames = num_frames;
157 num_samples = num_frames * ctx->channels;
158 data.output_frames = num_frames * ctx->ratio + 1;
159 out_samples = data.output_frames * ctx->channels;
161 data.data_in = para_malloc(num_samples * sizeof(float));
162 src_short_to_float_array(in, data.data_in, num_samples);
163 data.data_out = para_malloc(out_samples * sizeof(float));
164 ret = src_process(ctx->src_state, &data);
167 PARA_ERROR_LOG("%s\n", src_strerror(ret));
169 return -E_LIBSAMPLERATE;
171 out_samples = data.output_frames_gen * ctx->channels;
172 out = para_malloc(out_samples * sizeof(short));
173 src_float_to_short_array(data.data_out, out, out_samples);
176 *result_frames = data.output_frames_gen;
177 return data.input_frames_used;
180 static int resample_post_select(__a_unused struct sched *s, void *context)
183 struct filter_node *fn = context;
184 struct resample_context *ctx = fn->private_data;
185 struct btr_node *btrn = fn->btrn;
187 size_t in_bytes, num_frames;
190 ret = check_wav_post_select(ctx->cwc);
193 ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
196 if (!ctx->src_state) {
197 ret = resample_init(fn);
201 if (ctx->source_sample_rate == U32_OPTVAL(DEST_SAMPLE_RATE, fn->lpr)) {
203 * No resampling necessary. We do not splice ourselves out
204 * though, since our children might want to ask us through the
205 * btr exec mechanism for the destination samplerate and the
211 btr_merge(btrn, fn->min_iqs);
212 in_bytes = btr_next_buffer(btrn, (char **)&in);
213 ret = -E_RESAMPLE_EOF;
214 num_frames = in_bytes / 2 / ctx->channels;
217 have_more = !btr_no_parent(btrn) ||
218 btr_next_buffer_omit(btrn, in_bytes, NULL) > 0;
219 ret = resample_frames(in, num_frames, have_more, ctx, &out, &num_frames);
222 btr_consume(btrn, ret * 2 * ctx->channels);
223 btr_add_output((char *)out, num_frames * 2 * ctx->channels, btrn);
227 btr_remove_node(&fn->btrn);
228 /* This releases the check_wav btr node */
229 check_wav_post_select(ctx->cwc);
234 static void *resample_setup(const struct lls_parse_result *lpr)
236 int given, *converter;
237 const char *converter_arg;
241 u32 = U32_OPTVAL(CHANNELS, lpr);
242 given = OPT_GIVEN(CHANNELS, lpr);
243 if (u32 == 0 && given) {
244 PARA_EMERG_LOG("fatal: zero channels?!\n");
247 u32 = U32_OPTVAL(SAMPLE_RATE, lpr);
248 given = OPT_GIVEN(SAMPLE_RATE, lpr);
249 if (u32 == 0 && given) {
250 PARA_EMERG_LOG("fatal: input sample rate can not be 0\n");
253 u32 = U32_OPTVAL(DEST_SAMPLE_RATE, lpr);
254 given = OPT_GIVEN(DEST_SAMPLE_RATE, lpr);
255 if (u32 == 0 && given) {
256 PARA_EMERG_LOG("fatal: destination sample rate can not be 0\n");
259 converter = para_malloc(sizeof(int));
260 converter_arg = FILTER_CMD_OPT_STRING_VAL(RESAMPLE, CONVERTER, lpr);
261 if (!strcmp(converter_arg, "best"))
262 *converter = SRC_SINC_BEST_QUALITY;
263 else if (!strcmp(converter_arg, "medium"))
264 *converter = SRC_SINC_MEDIUM_QUALITY;
265 else if (!strcmp(converter_arg, "fastest"))
266 *converter = SRC_SINC_FASTEST;
267 else if (!strcmp(converter_arg, "zero_order_hold"))
268 *converter = SRC_ZERO_ORDER_HOLD;
269 else if (!strcmp(converter_arg, "linear"))
270 *converter = SRC_LINEAR;
272 PARA_EMERG_LOG("invalid converter type: %s\n", converter_arg);
278 static void resample_teardown(__a_unused const struct lls_parse_result *lpr,
284 const struct filter lsg_filter_cmd_com_resample_user_data = {
285 .setup = resample_setup,
286 .open = resample_open,
287 .pre_select = resample_pre_select,
288 .post_select = resample_post_select,
289 .close = resample_close,
290 .teardown = resample_teardown,
291 .execute = resample_execute