/* Copy function for baseband data that does a partial
* corner turn (or transpose) based on nchan. In this case
* out should point to the beginning of the data buffer.
* block_pkt_idx is the seq number of this packet relative
* to the beginning of the block. packets_per_block
* is the total number of packets per data block (all channels).
*/
void guppi_udp_packet_data_copy_transpose(char *databuf, int nchan,
unsigned block_pkt_idx, unsigned packets_per_block,
const struct guppi_udp_packet *p) {
const unsigned chan_per_packet = nchan;
const size_t bytes_per_sample = 4;
const unsigned samp_per_packet = guppi_udp_packet_datasize(p->packet_size)
/ bytes_per_sample / chan_per_packet;
const unsigned samp_per_block = packets_per_block * samp_per_packet;
char *iptr, *optr;
unsigned isamp,ichan;
iptr = guppi_udp_packet_data(p);
for (isamp=0; isamp<samp_per_packet; isamp++) {
optr = databuf + bytes_per_sample * (block_pkt_idx*samp_per_packet
+ isamp);
for (ichan=0; ichan<chan_per_packet; ichan++) {
memcpy(optr, iptr, bytes_per_sample);
iptr += bytes_per_sample;
optr += bytes_per_sample*samp_per_block;
}
}
#if 0
// Old version...
const unsigned pkt_idx = block_pkt_idx / nchan;
const unsigned ichan = block_pkt_idx % nchan;
const unsigned offset = ichan * packets_per_block / nchan + pkt_idx;
memcpy(databuf + offset*guppi_udp_packet_datasize(p->packet_size),
guppi_udp_packet_data(p),
guppi_udp_packet_datasize(p->packet_size));
#endif
}
/* Copy the data portion of a guppi udp packet to the given output
* address. This function takes care of expanding out the
* "missing" channels in 1SFA packets.
*/
void guppi_udp_packet_data_copy(char *out, const struct guppi_udp_packet *p) {
if (p->packet_size==PACKET_SIZE_1SFA_OLD) {
/* Expand out, leaving space for missing data. So far only
* need to deal with 4k-channel case of 2 spectra per packet.
* May need to be updated in the future if 1SFA works with
* different numbers of channels.
*
* TODO: Update 5/12/2009, newer 1SFA modes always will have full
* data contents, and the old 4k ones never really worked, so
* this code can probably be deleted.
*/
const size_t pad = 16;
const size_t spec_data_size = 4096 - 2*pad;
memset(out, 0, pad);
memcpy(out + pad, guppi_udp_packet_data(p), spec_data_size);
memset(out + pad + spec_data_size, 0, 2*pad);
memcpy(out + pad + spec_data_size + pad + pad,
guppi_udp_packet_data(p) + spec_data_size,
spec_data_size);
memset(out + pad + spec_data_size + pad
+ pad + spec_data_size, 0, pad);
} else {
/* Packet has full data, just do a memcpy */
memcpy(out, guppi_udp_packet_data(p),
guppi_udp_packet_datasize(p->packet_size));
}
}
