Skip to content

feature: Add lc3_encoder_disable_ltpf #72

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
asoulier merged 2 commits into from
Mar 4, 2025
Merged

feature: Add lc3_encoder_disable_ltpf #72

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
0e3a3d4
fix: Typo in the lc3_frame_block_bytes function implementation
anonymix007 Mar 2, 2025
7ce21db
feature: Add lc3_encoder_disable_ltpf
anonymix007 Feb 28, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 11 additions & 0 deletions include/lc3.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -355,6 +355,17 @@ LC3_EXPORT lc3_encoder_t lc3_hr_setup_encoder(
LC3_EXPORT lc3_encoder_t lc3_setup_encoder(
int dt_us, int sr_hz, int sr_pcm_hz, void *mem);

/**
* Disable LTPF analysis
* encoder Handle of the encoder
*
* LTPF analysis is known to take a lot of CPU time and work quite bad on
* synthetic signals such as sine waves, so it might be beneficial to
* disable it in such cases.
*/
LC3_EXPORT void lc3_encoder_disable_ltpf(
lc3_encoder_t encoder);

/**
* Encode a frame
* encoder Handle of the encoder
Expand Down
5 changes: 5 additions & 0 deletions include/lc3_cpp.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -137,6 +137,11 @@ class Encoder : public Base<struct lc3_encoder> {
}
}

void DisableLTPF() {
for (auto &s : states)
lc3_encoder_disable_ltpf(s.get());
}

~Encoder() override = default;

// Reset encoder state
Expand Down
2 changes: 2 additions & 0 deletions include/lc3_private.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -113,6 +113,8 @@ typedef struct lc3_spec_analysis {
} lc3_spec_analysis_t;

struct lc3_encoder {
bool ltpf_bypass;

enum lc3_dt dt;
enum lc3_srate sr, sr_pcm;

Expand Down
12 changes: 9 additions & 3 deletions src/lc3.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -122,7 +122,7 @@ LC3_EXPORT int lc3_hr_frame_block_bytes(
nchannels * lc3_max_frame_bytes(dt, sr) );
}

LC3_EXPORT int lc3_frame_bock_bytes(int dt_us, int nchannels, int bitrate)
LC3_EXPORT int lc3_frame_block_bytes(int dt_us, int nchannels, int bitrate)
{
return lc3_hr_frame_block_bytes(false, dt_us, 8000, nchannels, bitrate);
}
Expand Down Expand Up @@ -301,7 +301,7 @@ static void analyze(struct lc3_encoder *encoder,

bool att = lc3_attdet_run(dt, sr_pcm, nbytes, &encoder->attdet, xt);

side->pitch_present =
side->pitch_present = !encoder->ltpf_bypass &&
lc3_ltpf_analyse(dt, sr_pcm, &encoder->ltpf, xt, &side->ltpf);

memmove(xt - nt, xt + (ns-nt), nt * sizeof(*xt));
Expand All @@ -313,7 +313,7 @@ static void analyze(struct lc3_encoder *encoder,
lc3_mdct_forward(dt, sr_pcm, sr, xs, xd, xf);

bool nn_flag = lc3_energy_compute(dt, sr, xf, e);
if (nn_flag)
if (nn_flag || encoder->ltpf_bypass)
lc3_ltpf_disable(&side->ltpf);

side->bw = lc3_bwdet_run(dt, sr, e);
Expand Down Expand Up @@ -424,6 +424,12 @@ LC3_EXPORT struct lc3_encoder *lc3_setup_encoder(
return lc3_hr_setup_encoder(false, dt_us, sr_hz, sr_pcm_hz, mem);
}

LC3_EXPORT void lc3_encoder_disable_ltpf(
struct lc3_encoder *encoder)
{
encoder->ltpf_bypass = true;
}

/**
* Encode a frame
*/
Expand Down
Loading