diff --git a/src/whisper.cpp b/src/whisper.cpp index 5b6e4b4be48..df60466a57b 100644 --- a/src/whisper.cpp +++ b/src/whisper.cpp @@ -7695,7 +7695,7 @@ int whisper_full_with_state( whisper_exp_compute_token_level_timestamps( *ctx, *state, result_all.size() - 1, params.thold_pt, params.thold_ptsum); - if (params.max_len > 0) { + if (params.max_len > 0 && !ctx->params.dtw_token_timestamps) { n_new = whisper_wrap_segment(*ctx, *state, params.max_len, params.split_on_word); } } @@ -7708,15 +7708,14 @@ int whisper_full_with_state( // FIXME: will timestamp offsets be correct? // [EXPERIMENTAL] Token-level timestamps with DTW { - const int n_segments = state->result_all.size() - n_segments_before; + int n_segments = state->result_all.size() - n_segments_before; if (ctx->params.dtw_token_timestamps && n_segments) { const int n_frames = std::min(std::min(WHISPER_CHUNK_SIZE * 100, seek_delta), seek_end - seek); whisper_exp_compute_token_level_timestamps_dtw( ctx, state, params, result_all.size() - n_segments, n_segments, seek, n_frames, 7, params.n_threads); + if (params.new_segment_callback) { - for (int seg = (int) result_all.size() - n_segments; seg < n_segments; seg++) { - params.new_segment_callback(ctx, state, seg, params.new_segment_callback_user_data); - } + params.new_segment_callback(ctx, state, n_segments, params.new_segment_callback_user_data); } } } @@ -8949,6 +8948,140 @@ static void whisper_exp_compute_token_level_timestamps_dtw( } } + // DTW timestamp refinement constants (in centiseconds, 1 cs = 10ms) + // These values are tuned for natural speech at ~150 WPM + static const int64_t DTW_MIN_TOKEN_DUR = 5; // 50ms absolute minimum + static const int DTW_ONSET_VOWEL = 15; // 150ms for vowels/plosives (anticipate burst) + static const int DTW_ONSET_CONSONANT = 8; // 80ms for other consonants + static const int DTW_DUR_PER_CHAR = 2; // 20ms per character for min duration + static const int DTW_MAX_DUR_PER_CHAR = 15; // 150ms per character for max duration + static const int64_t DTW_MAX_DUR_BASE = 10; // 100ms base max duration + + // vowels + plosives benefit from earlier onset to match perceived speech start + static const char * DTW_ONSET_PHONEMES = "aeiouywbcdgkpqt"; + + // helper: get previous token's end time + auto get_prev_end = [&](size_t seg_idx, int tok_idx) -> int64_t { + auto & seg = state->result_all[seg_idx]; + for (int t2 = tok_idx - 1; t2 >= 0; --t2) { + if (seg.tokens[t2].id < whisper_token_eot(ctx)) { + return seg.tokens[t2].t_dtw; + } + } + if (seg_idx > 0 && !state->result_all[seg_idx - 1].tokens.empty()) { + return state->result_all[seg_idx - 1].tokens.back().t_dtw; + } + return 0; + }; + + // helper: get next token's start time + auto get_next_start = [&](size_t seg_idx, int tok_idx, int64_t fallback) -> int64_t { + auto & seg = state->result_all[seg_idx]; + const int n = seg.tokens.size(); + for (int t2 = tok_idx + 1; t2 < n; ++t2) { + if (seg.tokens[t2].id < whisper_token_eot(ctx)) { + return seg.tokens[t2].t_dtw; + } + } + if (seg_idx + 1 < state->result_all.size()) { + for (const auto & ntok : state->result_all[seg_idx + 1].tokens) { + if (ntok.id < whisper_token_eot(ctx)) { + return ntok.t_dtw; + } + } + } + return fallback; + }; + + // helper: get token text length (excluding leading space) + auto get_text_len = [&](whisper_token id) -> std::pair { + const char * text = whisper_token_to_str(ctx, id); + int len = text ? (int)strlen(text) : 1; + if (len > 0 && text && text[0] == ' ') { text++; len--; } + if (len < 1) len = 1; + return {text, len}; + }; + + // pass 1: onset shift + min duration adjustment + for (size_t i = i_segment; i < i_segment + n_segments; ++i) { + auto & segment = state->result_all[i]; + const int n_tokens = segment.tokens.size(); + + for (int t = 0; t < n_tokens; ++t) { + auto & tok = segment.tokens[t]; + if (tok.id >= whisper_token_eot(ctx)) continue; + + auto text_pair = get_text_len(tok.id); + const char * text = text_pair.first; + int len = text_pair.second; + + // onset shift: move start earlier for vowels/plosives + if (len > 0 && text) { + char c = tolower(text[0]); + int shift = 0; + if (strchr(DTW_ONSET_PHONEMES, c)) { + shift = DTW_ONSET_VOWEL; + } else if (c >= 'a' && c <= 'z') { + shift = DTW_ONSET_CONSONANT; + } + if (shift > 0) { + int64_t prev_end = get_prev_end(i, t); + if (tok.t_dtw - shift > prev_end + 1) { + tok.t_dtw -= shift; + } + } + } + + // min duration: extend backward if too short + int64_t next_start = get_next_start(i, t, segment.t1); + int64_t duration = next_start - tok.t_dtw; + int64_t len_based_min = (int64_t)(len * DTW_DUR_PER_CHAR); + int64_t adaptive_min = (DTW_MIN_TOKEN_DUR > len_based_min) ? DTW_MIN_TOKEN_DUR : len_based_min; + + if (duration >= 0 && duration < adaptive_min) { + int64_t prev_end = get_prev_end(i, t); + int64_t new_start = tok.t_dtw - (adaptive_min - duration); + if (new_start > prev_end + 2) { + tok.t_dtw = new_start; + } + } + } + } + + // pass 2: propagate t_dtw to t0/t1 with max duration cap + for (size_t i = i_segment; i < i_segment + n_segments; ++i) { + auto & segment = state->result_all[i]; + const int n_tokens = segment.tokens.size(); + + for (int t = 0; t < n_tokens; ++t) { + auto & tok = segment.tokens[t]; + if (tok.id >= whisper_token_eot(ctx)) continue; + + tok.t0 = tok.t_dtw; + + auto text_pair2 = get_text_len(tok.id); + int len2 = text_pair2.second; + int64_t next_start = get_next_start(i, t, segment.t1); + int64_t len_based_max = (int64_t)(len2 * DTW_MAX_DUR_PER_CHAR); + int64_t max_dur = (DTW_MAX_DUR_BASE > len_based_max) ? DTW_MAX_DUR_BASE : len_based_max; + + int64_t min_t1 = tok.t0 + DTW_MIN_TOKEN_DUR; + int64_t raw_t1 = (next_start > min_t1) ? next_start : min_t1; + tok.t1 = (raw_t1 - tok.t0 > max_dur) ? tok.t0 + max_dur : raw_t1; + } + + // sync segment boundaries with token bounds + int64_t first_t0 = -1, last_t1 = -1; + for (int t = 0; t < n_tokens; ++t) { + const auto & tok = segment.tokens[t]; + if (tok.id >= whisper_token_eot(ctx)) continue; + if (first_t0 < 0) first_t0 = tok.t0; + last_t1 = tok.t1; + } + if (first_t0 >= 0) segment.t0 = first_t0; + if (last_t1 >= 0) segment.t1 = last_t1; + } + // Print DTW timestamps /*for (size_t i = i_segment; i < i_segment + n_segments; ++i) { auto & segment = state->result_all[i];