2 * This file is part of the libsigrok project.
4 * Copyright (C) 2015 Uwe Hermann <uwe@hermann-uwe.de>
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 2 of the License, or
9 * (at your option) any later version.
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.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
23 #include <libsigrok/libsigrok.h>
24 #include "libsigrok-internal.h"
26 #define LOG_PREFIX "transform/scale"
29 struct sr_rational factor;
32 static int init(struct sr_transform *t, GHashTable *options)
36 if (!t || !t->sdi || !options)
39 t->priv = ctx = g_malloc0(sizeof(struct context));
41 g_variant_get(g_hash_table_lookup(options, "factor"), "(xt)",
42 &ctx->factor.p, &ctx->factor.q);
47 static int receive(const struct sr_transform *t,
48 struct sr_datafeed_packet *packet_in,
49 struct sr_datafeed_packet **packet_out)
52 const struct sr_datafeed_analog_old *analog_old;
53 const struct sr_datafeed_analog *analog;
54 struct sr_channel *ch;
58 int i, num_channels, c;
60 if (!t || !t->sdi || !packet_in || !packet_out)
64 switch (packet_in->type) {
65 case SR_DF_ANALOG_OLD:
66 analog_old = packet_in->payload;
67 fdata = (float *)analog_old->data;
68 num_channels = g_slist_length(analog_old->channels);
69 factor = (float) ctx->factor.p / ctx->factor.q;
70 for (i = 0; i < analog_old->num_samples; i++) {
71 /* For now scale all values in all channels. */
72 for (l = analog_old->channels, c = 0; l; l = l->next, c++) {
75 fdata[i * num_channels + c] *= factor;
80 analog = packet_in->payload;
81 analog->encoding->scale.p *= ctx->factor.p;
82 analog->encoding->scale.q *= ctx->factor.q;
85 sr_spew("Unsupported packet type %d, ignoring.", packet_in->type);
89 /* Return the in-place-modified packet. */
90 *packet_out = packet_in;
95 static int cleanup(struct sr_transform *t)
109 static struct sr_option options[] = {
110 { "factor", "Factor", "Factor by which to scale the analog values", NULL, NULL },
114 static const struct sr_option *get_options(void)
119 /* Default to a scaling factor of 1.0. */
121 options[0].def = g_variant_ref_sink(g_variant_new("(xt)", &p, &q));
126 SR_PRIV struct sr_transform_module transform_scale = {
129 .desc = "Scale analog values by a specified factor",
130 .options = get_options,