2 * Copyright (C) 2015 Tim Mayberry <mojofunk@gmail.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 #include "ardour/dsp_load_calculator.h"
24 DSPLoadCalculator::set_stop_timestamp_us(uint64_t stop_timestamp_us)
26 // We could only bother with calculations if a certain amount of time
27 // has passed, or the Raw DSP value is > X% different than last calc
28 // which would mean consistent overhead for small values of m_max_time_us
30 m_stop_timestamp_us = stop_timestamp_us;
33 if (elapsed_time_us() > m_max_time_us) {
36 load = elapsed_time_us() / (float)m_max_time_us;
39 assert(m_value_history.write_space() >= 1);
41 // push raw load value onto history
42 m_value_history.write(&load, 1);
44 // if load is under 80% use an average of past values
45 if (elapsed_time_us() < ((m_max_time_us * 80) / 100)) {
47 RingBuffer<float>::rw_vector vec;
48 m_value_history.get_read_vector(&vec);
49 uint32_t values_read = 0;
50 float dsp_accumulator = 0.0f;
52 // iterate through the read vectors accumulating the dsp load
53 for (unsigned int i = 0; i < vec.len[0]; ++i) {
54 dsp_accumulator += vec.buf[0][i];
58 for (unsigned int i = 0; i < vec.len[1]; ++i) {
59 dsp_accumulator += vec.buf[1][i];
63 load = dsp_accumulator / (float)values_read;
65 const float alpha = 0.2f * (m_max_time_us * 1e-6f);
66 m_dsp_load = m_dsp_load + alpha * (load - m_dsp_load) + 1e-12;
69 // Use raw load value otherwise 100% may never be indicated because of
74 if (m_value_history.read_space() >= m_num_values) {
75 // "remove" the oldest value
76 m_value_history.increment_read_idx(1);