lisyarus/psemek
1
0
Fork 1
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Support frequency resampling for wav audio

Browse source
This commit is contained in:
Nikita Lisitsa 2023-01-10 14:52:43 +03:00
parent 56505ebe85
commit 104d4a92a0
3 changed files with 19 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
libs/audio/include/psemek/audio/detail/resampler.hpp
View file

@ -26,6 +26,8 @@ namespace psemek::audio
return result_;
}
std::vector<float> grab_result();
private:
std::vector<float> result_;
int position_{0};

9
libs/audio/source/detail/resampler.cpp
View file

@ -67,6 +67,15 @@ namespace psemek::audio
last_sample_[1] = samples[samples.size() - 1];
}
std::vector<float> resampler::grab_result()
{
position_ = 0;
position_frac_ = 0.f;
last_sample_[0] = 0.f;
last_sample_[1] = 0.f;
return std::move(result_);
}
void resampler::advance(float delta)
{
position_frac_ += delta;

11
libs/audio/source/track_wav.cpp
View file

@ -1,5 +1,6 @@
#include <psemek/audio/track.hpp>
#include <psemek/audio/constants.hpp>
#include <psemek/audio/detail/resampler.hpp>
#include <psemek/util/to_string.hpp>
#include <psemek/util/at_scope_exit.hpp>
#include <psemek/sdl2/init.hpp>
@ -17,9 +18,6 @@ namespace psemek::audio
if (spec.channels > 2)
throw std::runtime_error(util::to_string("Can't convert audio with ", static_cast<int>(spec.channels), " channels"));
if (spec.freq != audio::frequency)
throw std::runtime_error(util::to_string("Can't convert audio with frequency ", spec.freq));
if (spec.format != AUDIO_S16SYS)
throw std::runtime_error(util::to_string("Can't convert audio with format ", spec.format));
@ -44,6 +42,13 @@ namespace psemek::audio
result[i] = (p[i] * 2.f + 1.f) / 65536.f;
}
if (spec.freq != audio::frequency)
{
audio::resampler resampler(audio::frequency * 1.f / spec.freq);
resampler.feed(result);
result = resampler.grab_result();
}
return result;
}