* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <string.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#define LOG_PREFIX "output/wav"
+/* Minimum/maximum number of samples per channel to put in a data chunk */
+#define MIN_DATA_CHUNK_SAMPLES 10
+
+struct out_context {
+ gboolean header_done;
+ uint64_t samplerate;
+ int num_channels;
+ GSList *channels;
+ int chanbuf_size;
+ int *chanbuf_used;
+ uint8_t **chanbuf;
+};
+
+static int realloc_chanbufs(const struct sr_output *o, int size)
+{
+ struct out_context *outc;
+ int i;
+
+ outc = o->priv;
+ for (i = 0; i < outc->num_channels; i++) {
+ if (!(outc->chanbuf[i] = g_try_realloc(outc->chanbuf[i], sizeof(float) * size))) {
+ sr_err("Unable to allocate enough output buffer memory.");
+ return SR_ERR;
+ }
+ outc->chanbuf_used[i] = 0;
+ }
+ outc->chanbuf_size = size;
+
+ return SR_OK;
+}
+
+static int flush_chanbufs(const struct sr_output *o, GString *out)
+{
+ struct out_context *outc;
+ int size, i, j;
+ char *buf, **bufp;
+
+ outc = o->priv;
+
+ /* Any one of them will do. */
+ size = outc->chanbuf_used[0];
+ if (!(buf = g_try_malloc(4 * size * outc->num_channels))) {
+ sr_err("Unable to allocate enough interleaved output buffer memory.");
+ return SR_ERR;
+ }
+ bufp = g_malloc(sizeof(char *) * outc->num_channels);
+ for (i = 0; i < outc->num_channels; i++)
+ bufp[i] = buf + i * 4;
+
+ for (i = 0; i < size * 4; i += 4) {
+ for (j = 0; j < outc->num_channels; j++) {
+ memcpy(bufp[j], outc->chanbuf[j] + i, 4);
+ bufp[j] += outc->num_channels * 4;
+ }
+ }
+ g_string_append_len(out, buf, 4 * size * outc->num_channels);
+ g_free(bufp);
+ g_free(buf);
+
+ for (i = 0; i < outc->num_channels; i++)
+ outc->chanbuf_used[i] = 0;
+
+ return SR_OK;
+}
+
static int init(struct sr_output *o, GHashTable *options)
{
- (void)o;
+ struct out_context *outc;
+ struct sr_channel *ch;
+ GSList *l;
+
(void)options;
+ outc = g_malloc0(sizeof(struct out_context));
+ o->priv = outc;
+
+ for (l = o->sdi->channels; l; l = l->next) {
+ ch = l->data;
+ if (ch->type != SR_CHANNEL_ANALOG)
+ continue;
+ if (!ch->enabled)
+ continue;
+ outc->channels = g_slist_append(outc->channels, ch);
+ outc->num_channels++;
+ }
+
+ outc->chanbuf = g_malloc0(sizeof(float *) * outc->num_channels);
+ outc->chanbuf_used = g_malloc0(sizeof(int) * outc->num_channels);
+
+ /* Start off the interleaved buffer with 100 samples/channel. */
+ realloc_chanbufs(o, 100);
+
return SR_OK;
}
+static void add_data_chunk(const struct sr_output *o, GString *gs)
+{
+ struct out_context *outc;
+ char tmp[4];
+
+ outc = o->priv;
+ g_string_append(gs, "fmt ");
+ /* Remaining chunk size */
+ WL32(tmp, 0x12);
+ g_string_append_len(gs, tmp, 4);
+ /* Format code 3 = IEEE float */
+ WL16(tmp, 0x0003);
+ g_string_append_len(gs, tmp, 2);
+ /* Number of channels */
+ WL16(tmp, outc->num_channels);
+ g_string_append_len(gs, tmp, 2);
+ /* Samplerate */
+ WL32(tmp, outc->samplerate);
+ g_string_append_len(gs, tmp, 4);
+ /* Byterate, using 32-bit floats. */
+ WL32(tmp, outc->samplerate * outc->num_channels * 4);
+ g_string_append_len(gs, tmp, 4);
+ /* Blockalign */
+ WL16(tmp, outc->num_channels * 4);
+ g_string_append_len(gs, tmp, 2);
+ /* Bits per sample */
+ WL16(tmp, 32);
+ g_string_append_len(gs, tmp, 2);
+ WL16(tmp, 0);
+ g_string_append_len(gs, tmp, 2);
+
+ g_string_append(gs, "data");
+ /* Data chunk size, max it out. */
+ WL32(tmp, 0xffffffff);
+ g_string_append_len(gs, tmp, 4);
+}
+
+static GString *gen_header(const struct sr_output *o)
+{
+ struct out_context *outc;
+ GVariant *gvar;
+ GString *header;
+ char tmp[4];
+
+ outc = o->priv;
+ if (outc->samplerate == 0) {
+ if (sr_config_get(o->sdi->driver, o->sdi, NULL, SR_CONF_SAMPLERATE,
+ &gvar) == SR_OK) {
+ outc->samplerate = g_variant_get_uint64(gvar);
+ g_variant_unref(gvar);
+ }
+ }
+
+ header = g_string_sized_new(512);
+ g_string_append(header, "RIFF");
+ /* Total size. Max out the field. */
+ WL32(tmp, 0xffffffff);
+ g_string_append_len(header, tmp, 4);
+ g_string_append(header, "WAVE");
+ add_data_chunk(o, header);
+
+ return header;
+}
+
+/*
+ * Stores the float in little-endian BINARY32 IEEE-754 2008 format.
+ */
+static void float_to_le(uint8_t *buf, float value)
+{
+ char *old;
+
+ old = (char *)&value;
+#ifdef WORDS_BIGENDIAN
+ buf[0] = old[3];
+ buf[1] = old[2];
+ buf[2] = old[1];
+ buf[3] = old[0];
+#else
+ buf[0] = old[0];
+ buf[1] = old[1];
+ buf[2] = old[2];
+ buf[3] = old[3];
+#endif
+}
+
+/*
+ * Returns the number of samples used in the current channel buffers,
+ * or -1 if they're not all the same.
+ */
+static int check_chanbuf_size(const struct sr_output *o)
+{
+ struct out_context *outc;
+ int size, i;
+
+ outc = o->priv;
+ size = 0;
+ for (i = 0; i < outc->num_channels; i++) {
+ if (size == 0) {
+ if (outc->chanbuf_used[i] == 0) {
+ /* Nothing in all the buffers yet. */
+ size = -1;
+ break;
+ } else
+ /* New high water mark. */
+ size = outc->chanbuf_used[i];
+ } else if (outc->chanbuf_used[i] != size) {
+ /* All channel buffers are not equally full yet. */
+ size = -1;
+ break;
+ }
+ }
+
+ return size;
+}
static int receive(const struct sr_output *o, const struct sr_datafeed_packet *packet,
GString **out)
{
- (void)o;
- (void)packet;
- (void)out;
+ struct out_context *outc;
+ const struct sr_datafeed_meta *meta;
+ const struct sr_datafeed_analog *analog;
+ const struct sr_config *src;
+ struct sr_channel *ch;
+ GSList *l;
+ int num_channels, size, *chan_idx, idx, i, j;
+ uint8_t *buf;
+
+ *out = NULL;
+ if (!o || !o->sdi || !(outc = o->priv))
+ return SR_ERR_ARG;
+
+ switch (packet->type) {
+ case SR_DF_META:
+ meta = packet->payload;
+ for (l = meta->config; l; l = l->next) {
+ src = l->data;
+ if (src->key != SR_CONF_SAMPLERATE)
+ continue;
+ outc->samplerate = g_variant_get_uint64(src->data);
+ }
+ break;
+ case SR_DF_ANALOG:
+ if (!outc->header_done) {
+ *out = gen_header(o);
+ outc->header_done = TRUE;
+ } else
+ *out = g_string_sized_new(512);
+
+ analog = packet->payload;
+ if (analog->num_samples == 0)
+ return SR_OK;
+
+ num_channels = g_slist_length(analog->channels);
+ if (num_channels > outc->num_channels) {
+ sr_err("Packet has %d channels, but only %d were enabled.",
+ num_channels, outc->num_channels);
+ return SR_ERR;
+ }
+
+ if (analog->num_samples > outc->chanbuf_size) {
+ if (realloc_chanbufs(o, analog->num_samples) != SR_OK)
+ return SR_ERR_MALLOC;
+ }
+
+ /* Index the channels in this packet, so we can interleave quicker. */
+ chan_idx = g_malloc(sizeof(int) * outc->num_channels);
+ for (i = 0; i < num_channels; i++) {
+ ch = g_slist_nth_data(analog->channels, i);
+ chan_idx[i] = g_slist_index(outc->channels, ch);
+ }
+
+ for (i = 0; i < analog->num_samples; i++) {
+ for (j = 0; j < num_channels; j++) {
+ idx = chan_idx[j];
+ buf = outc->chanbuf[idx] + outc->chanbuf_used[idx]++ * 4;
+ float_to_le(buf, analog->data[i + j]);
+ }
+ }
+ g_free(chan_idx);
+
+ size = check_chanbuf_size(o);
+ if (size > MIN_DATA_CHUNK_SAMPLES)
+ if (flush_chanbufs(o, *out) != SR_OK)
+ return SR_ERR;
+ break;
+ case SR_DF_END:
+ size = check_chanbuf_size(o);
+ if (size > 0) {
+ *out = g_string_sized_new(4 * size * outc->num_channels);
+ if (flush_chanbufs(o, *out) != SR_OK)
+ return SR_ERR;
+ }
+ break;
+ }
return SR_OK;
}
static int cleanup(struct sr_output *o)
{
- (void)o;
+ struct out_context *outc;
+ int i;
+
+ outc = o->priv;
+ g_slist_free(outc->channels);
+ for (i = 0; i < outc->num_channels; i++)
+ g_free(outc->chanbuf[i]);
+ g_free(outc->chanbuf_used);
+ g_free(outc->chanbuf);
+ g_free(outc);
+ o->priv = NULL;
return SR_OK;
}
SR_PRIV struct sr_output_module output_wav = {
.id = "wav",
.name = "WAV",
- .desc = "WAVE PCM sound module",
+ .desc = "WAVE file format",
.init = init,
.receive = receive,
.cleanup = cleanup,
projects / libsigrok.git / commitdiff