File size: 3,344 Bytes
2517be1 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 | #pragma once
#include "ggml.h"
#include "clip-model.h"
#include <cstdint>
#include <vector>
#include <string>
#define MTMD_INTERNAL_HEADER
struct mtmd_audio_mel {
int n_len;
int n_len_org;
int n_mel;
std::vector<float> data;
};
struct mtmd_audio_mel_filters {
int32_t n_mel;
int32_t n_fft;
std::vector<float> data;
};
// cache for audio processing, each processor instance owns its own cache
struct mtmd_audio_cache {
std::vector<float> sin_vals;
std::vector<float> cos_vals;
std::vector<float> hann_window;
mtmd_audio_mel_filters filters;
void fill_sin_cos_table(int n);
void fill_hann_window(int length, bool periodic);
// Build mel filterbank matrix [n_mel × n_fft_bins] at runtime.
// n_fft_bins must be (N_fft / 2 + 1). Example: if N_fft=512 -> n_fft_bins=257.
void fill_mel_filterbank_matrix(int n_mel,
int n_fft,
int sample_rate, // e.g. 16000
float fmin = 0.0f, // e.g. 0.0
float fmax = -1.0f, // e.g. sr/2; pass -1 for auto
bool slaney_area_norm = true,
float scale = 1.0f // optional extra scaling
);
};
struct mtmd_audio_preprocessor {
const clip_hparams & hparams;
mtmd_audio_preprocessor(const clip_ctx * ctx): hparams(*clip_get_hparams(ctx)) {}
virtual ~mtmd_audio_preprocessor() = default;
virtual void initialize() = 0; // NOT thread-safe
virtual bool preprocess(const float * samples, size_t n_samples, std::vector<mtmd_audio_mel> & output) = 0;
};
struct mtmd_audio_preprocessor_whisper : mtmd_audio_preprocessor {
mtmd_audio_preprocessor_whisper(const clip_ctx * ctx) : mtmd_audio_preprocessor(ctx) {}
void initialize() override;
bool preprocess(const float * samples, size_t n_samples, std::vector<mtmd_audio_mel> & output) override;
private:
mtmd_audio_cache cache;
};
struct mtmd_audio_preprocessor_conformer : mtmd_audio_preprocessor {
mtmd_audio_preprocessor_conformer(const clip_ctx * ctx) : mtmd_audio_preprocessor(ctx) {}
void initialize() override;
bool preprocess(const float * samples, size_t n_samples, std::vector<mtmd_audio_mel> & output) override;
private:
mtmd_audio_cache cache;
};
//
// streaming ISTFT - converts spectrogram frames back to audio one frame at a time
//
struct mtmd_audio_streaming_istft {
mtmd_audio_streaming_istft(int n_fft, int hop_length);
// reset streaming state
void reset();
// process a single STFT frame (streaming)
// frame_spectrum: [n_fft_bins x 2] interleaved real/imag
// returns: up to hop_length samples
std::vector<float> process_frame(const float * frame_spectrum);
// flush remaining samples at end of stream
std::vector<float> flush();
private:
int n_fft;
int hop_length;
int n_fft_bins;
// Own cache for output processing
mtmd_audio_cache cache;
// Streaming state
std::vector<float> overlap_buffer;
std::vector<float> window_sum_buffer;
int padding_to_remove;
// Working buffers for IFFT
std::vector<float> ifft_in;
std::vector<float> ifft_out;
};
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