main : add some comments for the word-level timestamp algorithm

This commit is contained in:
Georgi Gerganov 2022-11-01 22:35:21 +02:00
parent 0729da9a3b
commit 6fb98370ba
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@ -321,124 +321,125 @@ bool output_srt(struct whisper_context * ctx, const char * fname, const whisper_
}
// word-level timestamps (experimental)
// TODO: probably still has bugs, needs refactoring, etc..
// TODO: auto threshold
// TODO: make ffmpeg output optional
// TODO: extra pass to detect unused speech and assign to tokens
// TODO: font parameter adjustments
// TODO: move to whisper.h/whisper.cpp and add parameter to select max line-length of subtitles
bool output_wts(struct whisper_context * ctx, const char * fname, const char * fname_inp, const whisper_params & params, const std::vector<float> & pcmf32) {
if (params.output_wts) {
std::vector<float> pcm_avg(pcmf32.size(), 0);
std::vector<float> pcm_avg(pcmf32.size(), 0);
// average the fabs of the signal
{
const int hw = 32;
// average the fabs of the signal
{
const int hw = 32;
for (int i = 0; i < pcmf32.size(); i++) {
float sum = 0;
for (int j = -hw; j <= hw; j++) {
if (i + j >= 0 && i + j < pcmf32.size()) {
sum += fabs(pcmf32[i + j]);
}
for (int i = 0; i < pcmf32.size(); i++) {
float sum = 0;
for (int j = -hw; j <= hw; j++) {
if (i + j >= 0 && i + j < pcmf32.size()) {
sum += fabs(pcmf32[i + j]);
}
pcm_avg[i] = sum/(2*hw + 1);
}
pcm_avg[i] = sum/(2*hw + 1);
}
}
struct token_info {
int64_t t0 = -1;
int64_t t1 = -1;
int64_t tt0 = -1;
int64_t tt1 = -1;
whisper_token id;
whisper_token tid;
float p = 0.0f;
float pt = 0.0f;
float ptsum = 0.0f;
std::string text;
float vlen = 0.0f; // voice length of this token
};
int64_t t_beg = 0;
int64_t t_last = 0;
whisper_token tid_last = 0;
std::ofstream fout(fname);
fprintf(stderr, "%s: saving output to '%s'\n", __func__, fname);
fout << "!/bin/bash" << "\n";
fout << "\n";
fout << "ffmpeg -i " << fname_inp << " -f lavfi -i color=size=1200x120:duration=" << float(pcmf32.size() + 1000)/WHISPER_SAMPLE_RATE << ":rate=25:color=black -vf \"";
bool is_first = true;
for (int i = 0; i < whisper_full_n_segments(ctx); i++) {
const int64_t t0 = whisper_full_get_segment_t0(ctx, i);
const int64_t t1 = whisper_full_get_segment_t1(ctx, i);
const char *text = whisper_full_get_segment_text(ctx, i);
const int s0 = std::max(0, (int) (t0*WHISPER_SAMPLE_RATE/100));
const int s1 = std::min((int) pcmf32.size(), (int) (t1*WHISPER_SAMPLE_RATE/100));
const int n = whisper_full_n_tokens(ctx, i);
std::vector<token_info> tokens(n);
if (n <= 1) {
continue;
}
for (int j = 0; j < n; ++j) {
struct whisper_token_data token = whisper_full_get_token_data(ctx, i, j);
if (j == 0) {
if (token.id == whisper_token_beg(ctx)) {
tokens[j ].t0 = t0;
tokens[j ].t1 = t0;
tokens[j + 1].t0 = t0;
t_beg = t0;
t_last = t0;
tid_last = whisper_token_beg(ctx);
} else {
tokens[j ].t0 = t_last;
}
}
const int64_t tt = t_beg + 2*(token.tid - whisper_token_beg(ctx));
tokens[j].id = token.id;
tokens[j].tid = token.tid;
tokens[j].p = token.p;
tokens[j].pt = token.pt;
tokens[j].ptsum = token.ptsum;
tokens[j].text = whisper_token_to_str(ctx, token.id);
tokens[j].vlen = voice_length(tokens[j].text);
if (token.pt > params.word_thold && token.ptsum > 0.01 && token.tid > tid_last && tt <= t1) {
if (j > 0) {
tokens[j - 1].t1 = tt;
}
tokens[j].t0 = tt;
tid_last = token.tid;
}
}
struct token_info {
int64_t t0 = -1;
int64_t t1 = -1;
tokens[n - 2].t1 = t1;
tokens[n - 1].t0 = t1;
tokens[n - 1].t1 = t1;
int64_t tt0 = -1;
int64_t tt1 = -1;
whisper_token id;
whisper_token tid;
float p = 0.0f;
float pt = 0.0f;
float ptsum = 0.0f;
std::string text;
float vlen = 0.0f; // voice length of this token
};
int64_t t_beg = 0;
int64_t t_last = 0;
whisper_token tid_last = 0;
std::ofstream fout(fname);
fprintf(stderr, "%s: saving output to '%s'\n", __func__, fname);
fout << "!/bin/bash" << "\n";
fout << "\n";
fout << "ffmpeg -i " << fname_inp << " -f lavfi -i color=size=1200x120:duration=" << float(pcmf32.size() + 1000)/WHISPER_SAMPLE_RATE << ":rate=25:color=black -vf \"";
bool is_first = true;
for (int i = 0; i < whisper_full_n_segments(ctx); i++) {
const int64_t t0 = whisper_full_get_segment_t0(ctx, i);
const int64_t t1 = whisper_full_get_segment_t1(ctx, i);
const char *text = whisper_full_get_segment_text(ctx, i);
const int s0 = std::max(0, (int) (t0*WHISPER_SAMPLE_RATE/100));
const int s1 = std::min((int) pcmf32.size(), (int) (t1*WHISPER_SAMPLE_RATE/100));
const int n = whisper_full_n_tokens(ctx, i);
std::vector<token_info> tokens(n);
if (n <= 1) {
continue;
}
for (int j = 0; j < n; ++j) {
struct whisper_token_data token = whisper_full_get_token_data(ctx, i, j);
if (j == 0) {
if (token.id == whisper_token_beg(ctx)) {
tokens[j ].t0 = t0;
tokens[j ].t1 = t0;
tokens[j + 1].t0 = t0;
t_beg = t0;
t_last = t0;
tid_last = whisper_token_beg(ctx);
} else {
tokens[j ].t0 = t_last;
}
}
const int64_t tt = t_beg + 2*(token.tid - whisper_token_beg(ctx));
tokens[j].id = token.id;
tokens[j].tid = token.tid;
tokens[j].p = token.p;
tokens[j].pt = token.pt;
tokens[j].ptsum = token.ptsum;
tokens[j].text = whisper_token_to_str(ctx, token.id);
//tokens[j].vlen = tokens[j].pt;
tokens[j].vlen = voice_length(tokens[j].text);
if (token.pt > params.word_thold && token.ptsum > 0.01 && token.tid > tid_last && tt <= t1) {
if (j > 0) {
tokens[j - 1].t1 = tt;
}
tokens[j].t0 = tt;
tid_last = token.tid;
}
}
tokens[n - 2].t1 = t1;
tokens[n - 1].t0 = t1;
tokens[n - 1].t1 = t1;
t_last = t1;
t_last = t1;
// find intervals of tokens with unknown timestamps
// fill the timestamps by proportionally splitting the interval based on the token voice lengths
{
int p0 = 0;
int p1 = 0;
while (true) {
@ -460,10 +461,9 @@ bool output_wts(struct whisper_context * ctx, const char * fname, const char * f
const double dt = tokens[p1].t1 - tokens[p0].t0;
// split the time proportionally to the voice length
for (int j = p0 + 1; j <= p1; j++) {
const double ct = tokens[j - 1].t0 + dt*tokens[j - 1].vlen/psum;
//const double ct = tokens[j - 1].t0 + (dt*(j - p0))/(p1 - p0 + 1);
//const double ct = tokens[p0].t0 + (dt*(j - p0))/(p1 - p0 + 1);
tokens[j - 1].t1 = ct;
tokens[j ].t0 = ct;
@ -476,95 +476,100 @@ bool output_wts(struct whisper_context * ctx, const char * fname, const char * f
break;
}
}
}
for (int j = 0; j < n - 1; j++) {
if (tokens[j].t1 < 0) {
tokens[j + 1].t0 = tokens[j].t1;
}
if (j > 0) {
if (tokens[j - 1].t1 > tokens[j].t0) {
tokens[j].t0 = tokens[j - 1].t1;
tokens[j].t1 = std::max(tokens[j].t0, tokens[j].t1);
}
}
tokens[j].tt0 = tokens[j].t0;
tokens[j].tt1 = tokens[j].t1;
// fix up (just in case)
for (int j = 0; j < n - 1; j++) {
if (tokens[j].t1 < 0) {
tokens[j + 1].t0 = tokens[j].t1;
}
// VAD
{
const int hw = WHISPER_SAMPLE_RATE/8;
if (j > 0) {
if (tokens[j - 1].t1 > tokens[j].t0) {
tokens[j].t0 = tokens[j - 1].t1;
tokens[j].t1 = std::max(tokens[j].t0, tokens[j].t1);
}
}
for (int j = 0; j < n; j++) {
if (tokens[j].id >= whisper_token_eot(ctx)) {
continue;
}
tokens[j].tt0 = tokens[j].t0;
tokens[j].tt1 = tokens[j].t1;
}
const int64_t t0 = tokens[j].t0;
const int64_t t1 = tokens[j].t1;
// VAD
// expand or contract tokens based on voice activity
{
const int hw = WHISPER_SAMPLE_RATE/8;
int s0 = std::max(0, (int) (t0*WHISPER_SAMPLE_RATE/100));
int s1 = std::min((int) pcmf32.size() - 1, (int) (t1*WHISPER_SAMPLE_RATE/100));
for (int j = 0; j < n; j++) {
if (tokens[j].id >= whisper_token_eot(ctx)) {
continue;
}
const int ss0 = std::max(0, (int) (t0*WHISPER_SAMPLE_RATE/100) - hw);
const int ss1 = std::min((int) pcmf32.size() - 1, (int) (t1*WHISPER_SAMPLE_RATE/100) + hw);
const int64_t t0 = tokens[j].t0;
const int64_t t1 = tokens[j].t1;
const int n = ss1 - ss0;
int s0 = std::max(0, (int) (t0*WHISPER_SAMPLE_RATE/100));
int s1 = std::min((int) pcmf32.size() - 1, (int) (t1*WHISPER_SAMPLE_RATE/100));
float sum = 0.0f;
const int ss0 = std::max(0, (int) (t0*WHISPER_SAMPLE_RATE/100) - hw);
const int ss1 = std::min((int) pcmf32.size() - 1, (int) (t1*WHISPER_SAMPLE_RATE/100) + hw);
for (int k = ss0; k < ss1; k++) {
sum += pcm_avg[k];
}
const int n = ss1 - ss0;
const float thold = 0.5*sum/n;
float sum = 0.0f;
{
int k = s0;
if (pcm_avg[k] > thold && j > 0) {
while (k > 0 && pcm_avg[k] > thold) {
k--;
}
tokens[j].t0 = (int64_t) (100*k/WHISPER_SAMPLE_RATE);
if (tokens[j].t0 < tokens[j - 1].t1) {
tokens[j].t0 = tokens[j - 1].t1;
} else {
s0 = k;
}
for (int k = ss0; k < ss1; k++) {
sum += pcm_avg[k];
}
const float thold = 0.5*sum/n;
{
int k = s0;
if (pcm_avg[k] > thold && j > 0) {
while (k > 0 && pcm_avg[k] > thold) {
k--;
}
tokens[j].t0 = (int64_t) (100*k/WHISPER_SAMPLE_RATE);
if (tokens[j].t0 < tokens[j - 1].t1) {
tokens[j].t0 = tokens[j - 1].t1;
} else {
while (pcm_avg[k] < thold && k < s1) {
k++;
}
s0 = k;
tokens[j].t0 = 100*k/WHISPER_SAMPLE_RATE;
}
} else {
while (pcm_avg[k] < thold && k < s1) {
k++;
}
s0 = k;
tokens[j].t0 = 100*k/WHISPER_SAMPLE_RATE;
}
}
{
int k = s1;
if (pcm_avg[k] > thold) {
while (k < (int) pcmf32.size() - 1 && pcm_avg[k] > thold) {
k++;
}
tokens[j].t1 = 100*k/WHISPER_SAMPLE_RATE;
if (j < n - 1 && tokens[j].t1 > tokens[j + 1].t0) {
tokens[j].t1 = tokens[j + 1].t0;
} else {
s1 = k;
}
} else {
while (pcm_avg[k] < thold && k > s0) {
k--;
}
s1 = k;
tokens[j].t1 = 100*k/WHISPER_SAMPLE_RATE;
{
int k = s1;
if (pcm_avg[k] > thold) {
while (k < (int) pcmf32.size() - 1 && pcm_avg[k] > thold) {
k++;
}
tokens[j].t1 = 100*k/WHISPER_SAMPLE_RATE;
if (j < n - 1 && tokens[j].t1 > tokens[j + 1].t0) {
tokens[j].t1 = tokens[j + 1].t0;
} else {
s1 = k;
}
} else {
while (pcm_avg[k] < thold && k > s0) {
k--;
}
s1 = k;
tokens[j].t1 = 100*k/WHISPER_SAMPLE_RATE;
}
}
}
}
// fixed token expand (optional)
{
const int t_expand = 0;
for (int j = 0; j < n; j++) {
@ -575,119 +580,122 @@ bool output_wts(struct whisper_context * ctx, const char * fname, const char * f
tokens[j].t1 = tokens[j].t1 + t_expand;
}
}
}
for (int j = 0; j < n; ++j) {
const auto & token = tokens[j];
const auto tt = token.pt > params.word_thold && token.ptsum > 0.01 ? whisper_token_to_str(ctx, token.tid) : "[?]";
printf("%s: %10s %6.3f %6.3f %6.3f %6.3f %5d %5d '%s'\n", __func__,
tt, token.p, token.pt, token.ptsum, token.vlen, (int) token.t0, (int) token.t1, token.text.c_str());
// debug info
// TODO: toggle via parameter
for (int j = 0; j < n; ++j) {
const auto & token = tokens[j];
const auto tt = token.pt > params.word_thold && token.ptsum > 0.01 ? whisper_token_to_str(ctx, token.tid) : "[?]";
printf("%s: %10s %6.3f %6.3f %6.3f %6.3f %5d %5d '%s'\n", __func__,
tt, token.p, token.pt, token.ptsum, token.vlen, (int) token.t0, (int) token.t1, token.text.c_str());
if (tokens[j].id >= whisper_token_eot(ctx)) {
continue;
}
//printf("[%s --> %s] %s\n", to_timestamp(token.t0).c_str(), to_timestamp(token.t1).c_str(), whisper_token_to_str(ctx, token.id));
//fout << "# " << to_timestamp(token.t0) << " --> " << to_timestamp(token.t1) << " " << whisper_token_to_str(ctx, token.id) << "\n";
if (tokens[j].id >= whisper_token_eot(ctx)) {
continue;
}
static const int line_wrap = 60;
static const char * font = "/System/Library/Fonts/Supplemental/Courier New Bold.ttf";
//printf("[%s --> %s] %s\n", to_timestamp(token.t0).c_str(), to_timestamp(token.t1).c_str(), whisper_token_to_str(ctx, token.id));
if (!is_first) {
fout << ",";
//fout << "# " << to_timestamp(token.t0) << " --> " << to_timestamp(token.t1) << " " << whisper_token_to_str(ctx, token.id) << "\n";
}
// TODO: become parameters
static const int line_wrap = 60;
static const char * font = "/System/Library/Fonts/Supplemental/Courier New Bold.ttf";
if (!is_first) {
fout << ",";
}
// background text
fout << "drawtext=fontfile='" << font << "':fontsize=24:fontcolor=gray:x=(w-text_w)/2:y=h/2:text='':enable='between(t," << t0/100.0 << "," << t0/100.0 << ")'";
is_first = false;
for (int j = 0; j < n; ++j) {
const auto & token = tokens[j];
if (tokens[j].id >= whisper_token_eot(ctx)) {
continue;
}
// background text
fout << "drawtext=fontfile='" << font << "':fontsize=24:fontcolor=gray:x=(w-text_w)/2:y=h/2:text='':enable='between(t," << t0/100.0 << "," << t0/100.0 << ")'";
std::string txt_bg;
std::string txt_fg; // highlight token
std::string txt_ul; // underline
is_first = false;
txt_bg = "> ";
txt_fg = "> ";
txt_ul = "\\ \\ ";
for (int j = 0; j < n; ++j) {
const auto & token = tokens[j];
{
int ncnt = 0;
for (int k = 0; k < n; ++k) {
const auto & token2 = tokens[k];
if (tokens[j].id >= whisper_token_eot(ctx)) {
continue;
}
if (tokens[k].id >= whisper_token_eot(ctx)) {
continue;
}
std::string txt_bg;
std::string txt_fg; // highlight token
std::string txt_ul; // underline
const std::string txt = whisper_token_to_str(ctx, token2.id);
txt_bg = "> ";
txt_fg = "> ";
txt_ul = "\\ \\ ";
txt_bg += txt;
{
int ncnt = 0;
for (int k = 0; k < n; ++k) {
const auto & token2 = tokens[k];
if (tokens[k].id >= whisper_token_eot(ctx)) {
continue;
if (k == j) {
for (int l = 0; l < (int) txt.size(); ++l) {
txt_fg += txt[l];
txt_ul += "_";
}
const std::string txt = whisper_token_to_str(ctx, token2.id);
txt_bg += txt;
if (k == j) {
for (int l = 0; l < (int) txt.size(); ++l) {
txt_fg += txt[l];
txt_ul += "_";
}
txt_fg += "|";
} else {
for (int l = 0; l < (int) txt.size(); ++l) {
txt_fg += "\\ ";
txt_ul += "\\ ";
}
}
ncnt += txt.size();
if (ncnt > line_wrap) {
if (k < j) {
txt_bg = "> ";
txt_fg = "> ";
txt_ul = "\\ \\ ";
ncnt = 0;
} else {
break;
}
txt_fg += "|";
} else {
for (int l = 0; l < (int) txt.size(); ++l) {
txt_fg += "\\ ";
txt_ul += "\\ ";
}
}
::replace_all(txt_bg, "'", "");
::replace_all(txt_bg, "\"", "\\\"");
::replace_all(txt_fg, "'", "");
::replace_all(txt_fg, "\"", "\\\"");
ncnt += txt.size();
if (ncnt > line_wrap) {
if (k < j) {
txt_bg = "> ";
txt_fg = "> ";
txt_ul = "\\ \\ ";
ncnt = 0;
} else {
break;
}
}
}
// background text
fout << ",drawtext=fontfile='" << font << "':fontsize=24:fontcolor=gray:x=(w-text_w)/2:y=h/2:text='" << txt_bg << "':enable='between(t," << token.tt0/100.0 << "," << token.tt1/100.0 << ")'";
// foreground text
fout << ",drawtext=fontfile='" << font << "':fontsize=24:fontcolor=lightgreen:x=(w-text_w)/2+8:y=h/2:text='" << txt_fg << "':enable='between(t," << token.t0/100.0 << "," << token.t1/100.0 << ")'";
// underline
fout << ",drawtext=fontfile='" << font << "':fontsize=24:fontcolor=lightgreen:x=(w-text_w)/2+8:y=h/2+16:text='" << txt_ul << "':enable='between(t," << token.t0/100.0 << "," << token.t1/100.0 << ")'";
::replace_all(txt_bg, "'", "");
::replace_all(txt_bg, "\"", "\\\"");
::replace_all(txt_fg, "'", "");
::replace_all(txt_fg, "\"", "\\\"");
}
// background text
fout << ",drawtext=fontfile='" << font << "':fontsize=24:fontcolor=gray:x=(w-text_w)/2:y=h/2:text='" << txt_bg << "':enable='between(t," << token.tt0/100.0 << "," << token.tt1/100.0 << ")'";
// foreground text
fout << ",drawtext=fontfile='" << font << "':fontsize=24:fontcolor=lightgreen:x=(w-text_w)/2+8:y=h/2:text='" << txt_fg << "':enable='between(t," << token.t0/100.0 << "," << token.t1/100.0 << ")'";
// underline
fout << ",drawtext=fontfile='" << font << "':fontsize=24:fontcolor=lightgreen:x=(w-text_w)/2+8:y=h/2+16:text='" << txt_ul << "':enable='between(t," << token.t0/100.0 << "," << token.t1/100.0 << ")'";
}
fout << "\" -c:v libx264 -pix_fmt yuv420p -y " << fname_inp << ".mp4" << "\n";
fout << "\n\n";
fout << "echo \"Your video has been saved to " << fname_inp << ".mp4\"" << "\n";
fout << "\n";
fout << "echo \" ffplay " << fname_inp << ".mp4\"\n";
fout << "\n";
fout.close();
fprintf(stderr, "%s: run 'source %s' to generate karaoke video\n", __func__, fname);
}
fout << "\" -c:v libx264 -pix_fmt yuv420p -y " << fname_inp << ".mp4" << "\n";
fout << "\n\n";
fout << "echo \"Your video has been saved to " << fname_inp << ".mp4\"" << "\n";
fout << "\n";
fout << "echo \" ffplay " << fname_inp << ".mp4\"\n";
fout << "\n";
fout.close();
fprintf(stderr, "%s: run 'source %s' to generate karaoke video\n", __func__, fname);
return true;
}