示例#1
0
		private static void TestFFT(string title, kiss_fft_cpx<float>[] timeDomain, kiss_fft_cpx<float>[] frequencyDomain)
		{
			System.Console.WriteLine(title);
			{ // FFT
				KissFFT<float> kissFft = new KissFFT<float>(timeDomain.Length, false, new FloatArithmetic());

				kissFft.kiss_fft(new Array<kiss_fft_cpx<float>>(timeDomain), new Array<kiss_fft_cpx<float>>(frequencyDomain));

				for (int i = 0; i < frequencyDomain.Length; ++i)
				{
					frequencyDomain[i].r /= (float) frequencyDomain.Length;
					frequencyDomain[i].i /= (float) frequencyDomain.Length;
				}

				System.Console.Write("Offset = {0} + {1} * i\n", frequencyDomain[0].r, frequencyDomain[0].i);
				for (int i = 1; i < frequencyDomain.Length / 2 + 1; ++i)
				{
					System.Console.Write("f({0}): {1} + {2} * i, ", i, frequencyDomain[i].r * 2.0f, frequencyDomain[i].i * 2.0f);
					PrintEuler(frequencyDomain[i].r * 2.0f, frequencyDomain[i].i * 2.0f);
					System.Console.WriteLine();
				}
			}
			{ // inverse FFT
				kiss_fft_cpx<float>[] inverted = new kiss_fft_cpx<float>[frequencyDomain.Length];

				KissFFT<float> kissFft = new KissFFT<float>(frequencyDomain.Length, true, new FloatArithmetic());

				kissFft.kiss_fft(new Array<kiss_fft_cpx<float>>(frequencyDomain), new Array<kiss_fft_cpx<float>>(inverted));

				for (int i = 0; i < frequencyDomain.Length; ++i)
				{
					const float treshold = 0.00001f;
					if (!(Math.Abs(timeDomain[i].r - inverted[i].r) < treshold && Math.Abs(timeDomain[i].i - inverted[i].i) < treshold))
					{
						System.Console.Write("{0} ({1}, {2}) != ({3}, {4})\n", i, timeDomain[i].r, timeDomain[i].i, inverted[i].r, inverted[i].i);
					}
				}
				System.Console.WriteLine();
			}
		}
示例#2
0
        private static void TestFFT(string title, kiss_fft_cpx <float>[] timeDomain, kiss_fft_cpx <float>[] frequencyDomain)
        {
            System.Console.WriteLine(title);
            {             // FFT
                KissFFT <float> kissFft = new KissFFT <float>(timeDomain.Length, false, new FloatArithmetic());

                kissFft.kiss_fft(new Array <kiss_fft_cpx <float> >(timeDomain), new Array <kiss_fft_cpx <float> >(frequencyDomain));

                for (int i = 0; i < frequencyDomain.Length; ++i)
                {
                    frequencyDomain[i].r /= (float)frequencyDomain.Length;
                    frequencyDomain[i].i /= (float)frequencyDomain.Length;
                }

                System.Console.Write("Offset = {0} + {1} * i\n", frequencyDomain[0].r, frequencyDomain[0].i);
                for (int i = 1; i < frequencyDomain.Length / 2 + 1; ++i)
                {
                    System.Console.Write("f({0}): {1} + {2} * i, ", i, frequencyDomain[i].r * 2.0f, frequencyDomain[i].i * 2.0f);
                    PrintEuler(frequencyDomain[i].r * 2.0f, frequencyDomain[i].i * 2.0f);
                    System.Console.WriteLine();
                }
            }
            {             // inverse FFT
                kiss_fft_cpx <float>[] inverted = new kiss_fft_cpx <float> [frequencyDomain.Length];

                KissFFT <float> kissFft = new KissFFT <float>(frequencyDomain.Length, true, new FloatArithmetic());

                kissFft.kiss_fft(new Array <kiss_fft_cpx <float> >(frequencyDomain), new Array <kiss_fft_cpx <float> >(inverted));

                for (int i = 0; i < frequencyDomain.Length; ++i)
                {
                    const float treshold = 0.00001f;
                    if (!(Math.Abs(timeDomain[i].r - inverted[i].r) < treshold && Math.Abs(timeDomain[i].i - inverted[i].i) < treshold))
                    {
                        System.Console.Write("{0} ({1}, {2}) != ({3}, {4})\n", i, timeDomain[i].r, timeDomain[i].i, inverted[i].r, inverted[i].i);
                    }
                }
                System.Console.WriteLine();
            }
        }
示例#3
0
        /// <summary>
        ///
        /// </summary>
        /// <typeparam name="T">The type of signal being handled (either short or float) - changes based on which API is used</typeparam>
        /// <param name="tonal"></param>
        /// <param name="celt_mode"></param>
        /// <param name="x"></param>
        /// <param name="len"></param>
        /// <param name="offset"></param>
        /// <param name="c1"></param>
        /// <param name="c2"></param>
        /// <param name="C"></param>
        /// <param name="lsb_depth"></param>
        /// <param name="downmix"></param>
        internal static void tonality_analysis <T>(TonalityAnalysisState tonal, CeltMode celt_mode, T[] x, int x_ptr, int len, int offset, int c1, int c2, int C, int lsb_depth, Downmix.downmix_func <T> downmix)
        {
            int      i, b;
            FFTState kfft;

            int[] input;
            int[] output;
            int   N = 480, N2 = 240;

            float[] A   = tonal.angle;
            float[] dA  = tonal.d_angle;
            float[] d2A = tonal.d2_angle;
            float[] tonality;
            float[] noisiness;
            float[] band_tonality = new float[OpusConstants.NB_TBANDS];
            float[] logE          = new float[OpusConstants.NB_TBANDS];
            float[] BFCC          = new float[8];
            float[] features      = new float[25];
            float   frame_tonality;
            float   max_frame_tonality;
            /*float tw_sum=0;*/
            float frame_noisiness;
            float pi4   = (float)(M_PI * M_PI * M_PI * M_PI);
            float slope = 0;
            float frame_stationarity;
            float relativeE;

            float[]      frame_probs = new float[2];
            float        alpha, alphaE, alphaE2;
            float        frame_loudness;
            float        bandwidth_mask;
            int          bandwidth = 0;
            float        maxE      = 0;
            float        noise_floor;
            int          remaining;
            AnalysisInfo info; //[porting note] pointer

            tonal.last_transition++;
            alpha   = 1.0f / Inlines.IMIN(20, 1 + tonal.count);
            alphaE  = 1.0f / Inlines.IMIN(50, 1 + tonal.count);
            alphaE2 = 1.0f / Inlines.IMIN(1000, 1 + tonal.count);

            if (tonal.count < 4)
            {
                tonal.music_prob = 0.5f;
            }
            kfft = celt_mode.mdct.kfft[0];
            if (tonal.count == 0)
            {
                tonal.mem_fill = 240;
            }

            downmix(x, x_ptr, tonal.inmem, tonal.mem_fill, Inlines.IMIN(len, OpusConstants.ANALYSIS_BUF_SIZE - tonal.mem_fill), offset, c1, c2, C);

            if (tonal.mem_fill + len < OpusConstants.ANALYSIS_BUF_SIZE)
            {
                tonal.mem_fill += len;
                /* Don't have enough to update the analysis */
                return;
            }

            info = tonal.info[tonal.write_pos++];
            if (tonal.write_pos >= OpusConstants.DETECT_SIZE)
            {
                tonal.write_pos -= OpusConstants.DETECT_SIZE;
            }

            input     = new int[960];
            output    = new int[960];
            tonality  = new float[240];
            noisiness = new float[240];
            for (i = 0; i < N2; i++)
            {
                float w = Tables.analysis_window[i];
                input[2 * i]                 = (int)(w * tonal.inmem[i]);
                input[2 * i + 1]             = (int)(w * tonal.inmem[N2 + i]);
                input[(2 * (N - i - 1))]     = (int)(w * tonal.inmem[N - i - 1]);
                input[(2 * (N - i - 1)) + 1] = (int)(w * tonal.inmem[N + N2 - i - 1]);
            }
            Arrays.MemMoveInt(tonal.inmem, OpusConstants.ANALYSIS_BUF_SIZE - 240, 0, 240);

            remaining = len - (OpusConstants.ANALYSIS_BUF_SIZE - tonal.mem_fill);
            downmix(x, x_ptr, tonal.inmem, 240, remaining, offset + OpusConstants.ANALYSIS_BUF_SIZE - tonal.mem_fill, c1, c2, C);
            tonal.mem_fill = 240 + remaining;

            KissFFT.opus_fft(kfft, input, output);

            for (i = 1; i < N2; i++)
            {
                float X1r, X2r, X1i, X2i;
                float angle, d_angle, d2_angle;
                float angle2, d_angle2, d2_angle2;
                float mod1, mod2, avg_mod;
                X1r = (float)output[2 * i] + output[2 * (N - i)];
                X1i = (float)output[(2 * i) + 1] - output[2 * (N - i) + 1];
                X2r = (float)output[(2 * i) + 1] + output[2 * (N - i) + 1];
                X2i = (float)output[2 * (N - i)] - output[2 * i];

                angle    = (float)(.5f / M_PI) * fast_atan2f(X1i, X1r);
                d_angle  = angle - A[i];
                d2_angle = d_angle - dA[i];

                angle2    = (float)(.5f / M_PI) * fast_atan2f(X2i, X2r);
                d_angle2  = angle2 - angle;
                d2_angle2 = d_angle2 - d_angle;

                mod1         = d2_angle - (float)Math.Floor(0.5f + d2_angle);
                noisiness[i] = Inlines.ABS16(mod1);
                mod1        *= mod1;
                mod1        *= mod1;

                mod2          = d2_angle2 - (float)Math.Floor(0.5f + d2_angle2);
                noisiness[i] += Inlines.ABS16(mod2);
                mod2         *= mod2;
                mod2         *= mod2;

                avg_mod     = .25f * (d2A[i] + 2.0f * mod1 + mod2);
                tonality[i] = 1.0f / (1.0f + 40.0f * 16.0f * pi4 * avg_mod) - .015f;

                A[i]   = angle2;
                dA[i]  = d_angle2;
                d2A[i] = mod2;
            }

            frame_tonality     = 0;
            max_frame_tonality = 0;
            /*tw_sum = 0;*/
            info.activity      = 0;
            frame_noisiness    = 0;
            frame_stationarity = 0;
            if (tonal.count == 0)
            {
                for (b = 0; b < OpusConstants.NB_TBANDS; b++)
                {
                    tonal.lowE[b]  = 1e10f;
                    tonal.highE[b] = -1e10f;
                }
            }
            relativeE      = 0;
            frame_loudness = 0;
            for (b = 0; b < OpusConstants.NB_TBANDS; b++)
            {
                float E = 0, tE = 0, nE = 0;
                float L1, L2;
                float stationarity;
                for (i = Tables.tbands[b]; i < Tables.tbands[b + 1]; i++)
                {
                    float binE = output[2 * i] * (float)output[2 * i] + output[2 * (N - i)] * (float)output[2 * (N - i)]
                                 + output[2 * i + 1] * (float)output[2 * i + 1] + output[2 * (N - i) + 1] * (float)output[2 * (N - i) + 1];
                    /* FIXME: It's probably best to change the BFCC filter initial state instead */
                    binE *= 5.55e-17f;
                    E    += binE;
                    tE   += binE * tonality[i];
                    nE   += binE * 2.0f * (.5f - noisiness[i]);
                }

                tonal.E[tonal.E_count][b] = E;
                frame_noisiness          += nE / (1e-15f + E);

                frame_loudness += (float)Math.Sqrt(E + 1e-10f);
                logE[b]         = (float)Math.Log(E + 1e-10f);
                tonal.lowE[b]   = Inlines.MIN32(logE[b], tonal.lowE[b] + 0.01f);
                tonal.highE[b]  = Inlines.MAX32(logE[b], tonal.highE[b] - 0.1f);
                if (tonal.highE[b] < tonal.lowE[b] + 1.0f)
                {
                    tonal.highE[b] += 0.5f;
                    tonal.lowE[b]  -= 0.5f;
                }
                relativeE += (logE[b] - tonal.lowE[b]) / (1e-15f + tonal.highE[b] - tonal.lowE[b]);

                L1 = L2 = 0;
                for (i = 0; i < OpusConstants.NB_FRAMES; i++)
                {
                    L1 += (float)Math.Sqrt(tonal.E[i][b]);
                    L2 += tonal.E[i][b];
                }

                stationarity        = Inlines.MIN16(0.99f, L1 / (float)Math.Sqrt(1e-15 + OpusConstants.NB_FRAMES * L2));
                stationarity       *= stationarity;
                stationarity       *= stationarity;
                frame_stationarity += stationarity;
                /*band_tonality[b] = tE/(1e-15+E)*/
                band_tonality[b] = Inlines.MAX16(tE / (1e-15f + E), stationarity * tonal.prev_band_tonality[b]);
                frame_tonality  += band_tonality[b];
                if (b >= OpusConstants.NB_TBANDS - OpusConstants.NB_TONAL_SKIP_BANDS)
                {
                    frame_tonality -= band_tonality[b - OpusConstants.NB_TBANDS + OpusConstants.NB_TONAL_SKIP_BANDS];
                }
                max_frame_tonality = Inlines.MAX16(max_frame_tonality, (1.0f + .03f * (b - OpusConstants.NB_TBANDS)) * frame_tonality);
                slope += band_tonality[b] * (b - 8);
                tonal.prev_band_tonality[b] = band_tonality[b];
            }

            bandwidth_mask = 0;
            bandwidth      = 0;
            maxE           = 0;
            noise_floor    = 5.7e-4f / (1 << (Inlines.IMAX(0, lsb_depth - 8)));
            noise_floor   *= 1 << (15 + CeltConstants.SIG_SHIFT);
            noise_floor   *= noise_floor;
            for (b = 0; b < OpusConstants.NB_TOT_BANDS; b++)
            {
                float E = 0;
                int   band_start, band_end;
                /* Keep a margin of 300 Hz for aliasing */
                band_start = Tables.extra_bands[b];
                band_end   = Tables.extra_bands[b + 1];
                for (i = band_start; i < band_end; i++)
                {
                    float binE = output[2 * i] * (float)output[2 * i] + output[2 * (N - i)] * (float)output[2 * (N - i)]
                                 + output[2 * i + 1] * (float)output[2 * i + 1] + output[2 * (N - i) + 1] * (float)output[2 * (N - i) + 1];
                    E += binE;
                }
                maxE           = Inlines.MAX32(maxE, E);
                tonal.meanE[b] = Inlines.MAX32((1 - alphaE2) * tonal.meanE[b], E);
                E = Inlines.MAX32(E, tonal.meanE[b]);
                /* Use a simple follower with 13 dB/Bark slope for spreading function */
                bandwidth_mask = Inlines.MAX32(.05f * bandwidth_mask, E);

                /* Consider the band "active" only if all these conditions are met:
                 * 1) less than 10 dB below the simple follower
                 * 2) less than 90 dB below the peak band (maximal masking possible considering
                 *    both the ATH and the loudness-dependent slope of the spreading function)
                 * 3) above the PCM quantization noise floor
                 */
                if (E > .1 * bandwidth_mask && E * 1e9f > maxE && E > noise_floor * (band_end - band_start))
                {
                    bandwidth = b;
                }
            }
            if (tonal.count <= 2)
            {
                bandwidth = 20;
            }
            frame_loudness   = 20 * (float)Math.Log10(frame_loudness);
            tonal.Etracker   = Inlines.MAX32(tonal.Etracker - .03f, frame_loudness);
            tonal.lowECount *= (1 - alphaE);
            if (frame_loudness < tonal.Etracker - 30)
            {
                tonal.lowECount += alphaE;
            }

            for (i = 0; i < 8; i++)
            {
                float sum = 0;
                for (b = 0; b < 16; b++)
                {
                    sum += Tables.dct_table[i * 16 + b] * logE[b];
                }
                BFCC[i] = sum;
            }

            frame_stationarity /= OpusConstants.NB_TBANDS;
            relativeE          /= OpusConstants.NB_TBANDS;
            if (tonal.count < 10)
            {
                relativeE = 0.5f;
            }
            frame_noisiness    /= OpusConstants.NB_TBANDS;
            info.activity       = frame_noisiness + (1 - frame_noisiness) * relativeE;
            frame_tonality      = (max_frame_tonality / (OpusConstants.NB_TBANDS - OpusConstants.NB_TONAL_SKIP_BANDS));
            frame_tonality      = Inlines.MAX16(frame_tonality, tonal.prev_tonality * .8f);
            tonal.prev_tonality = frame_tonality;

            slope /= 8 * 8;
            info.tonality_slope = slope;

            tonal.E_count = (tonal.E_count + 1) % OpusConstants.NB_FRAMES;
            tonal.count++;
            info.tonality = frame_tonality;

            for (i = 0; i < 4; i++)
            {
                features[i] = -0.12299f * (BFCC[i] + tonal.mem[i + 24]) + 0.49195f * (tonal.mem[i] + tonal.mem[i + 16]) + 0.69693f * tonal.mem[i + 8] - 1.4349f * tonal.cmean[i];
            }

            for (i = 0; i < 4; i++)
            {
                tonal.cmean[i] = (1 - alpha) * tonal.cmean[i] + alpha * BFCC[i];
            }

            for (i = 0; i < 4; i++)
            {
                features[4 + i] = 0.63246f * (BFCC[i] - tonal.mem[i + 24]) + 0.31623f * (tonal.mem[i] - tonal.mem[i + 16]);
            }
            for (i = 0; i < 3; i++)
            {
                features[8 + i] = 0.53452f * (BFCC[i] + tonal.mem[i + 24]) - 0.26726f * (tonal.mem[i] + tonal.mem[i + 16]) - 0.53452f * tonal.mem[i + 8];
            }

            if (tonal.count > 5)
            {
                for (i = 0; i < 9; i++)
                {
                    tonal.std[i] = (1 - alpha) * tonal.std[i] + alpha * features[i] * features[i];
                }
            }

            for (i = 0; i < 8; i++)
            {
                tonal.mem[i + 24] = tonal.mem[i + 16];
                tonal.mem[i + 16] = tonal.mem[i + 8];
                tonal.mem[i + 8]  = tonal.mem[i];
                tonal.mem[i]      = BFCC[i];
            }
            for (i = 0; i < 9; i++)
            {
                features[11 + i] = (float)Math.Sqrt(tonal.std[i]);
            }
            features[20] = info.tonality;
            features[21] = info.activity;
            features[22] = frame_stationarity;
            features[23] = info.tonality_slope;
            features[24] = tonal.lowECount;

            mlp.mlp_process(Tables.net, features, frame_probs);
            frame_probs[0] = .5f * (frame_probs[0] + 1);
            /* Curve fitting between the MLP probability and the actual probability */
            frame_probs[0] = .01f + 1.21f * frame_probs[0] * frame_probs[0] - .23f * (float)Math.Pow(frame_probs[0], 10);
            /* Probability of active audio (as opposed to silence) */
            frame_probs[1] = .5f * frame_probs[1] + .5f;
            /* Consider that silence has a 50-50 probability. */
            frame_probs[0] = frame_probs[1] * frame_probs[0] + (1 - frame_probs[1]) * .5f;

            /*printf("%f %f ", frame_probs[0], frame_probs[1]);*/
            {
                /* Probability of state transition */
                float tau;

                /* Represents independence of the MLP probabilities, where
                 *  beta=1 means fully independent. */
                float beta;
                /* Denormalized probability of speech (p0) and music (p1) after update */
                float p0, p1;
                /* Probabilities for "all speech" and "all music" */
                float s0, m0;
                /* Probability sum for renormalisation */
                float psum;
                /* Instantaneous probability of speech and music, with beta pre-applied. */
                float speech0;
                float music0;

                /* One transition every 3 minutes of active audio */
                tau  = .00005f * frame_probs[1];
                beta = .05f;
                //if (1)
                {
                    /* Adapt beta based on how "unexpected" the new prob is */
                    float p, q;
                    p    = Inlines.MAX16(.05f, Inlines.MIN16(.95f, frame_probs[0]));
                    q    = Inlines.MAX16(.05f, Inlines.MIN16(.95f, tonal.music_prob));
                    beta = .01f + .05f * Inlines.ABS16(p - q) / (p * (1 - q) + q * (1 - p));
                }

                /* p0 and p1 are the probabilities of speech and music at this frame
                 *  using only information from previous frame and applying the
                 *  state transition model */
                p0 = (1 - tonal.music_prob) * (1 - tau) + tonal.music_prob * tau;
                p1 = tonal.music_prob * (1 - tau) + (1 - tonal.music_prob) * tau;

                /* We apply the current probability with exponent beta to work around
                 *  the fact that the probability estimates aren't independent. */
                p0 *= (float)Math.Pow(1 - frame_probs[0], beta);
                p1 *= (float)Math.Pow(frame_probs[0], beta);
                /* Normalise the probabilities to get the Marokv probability of music. */
                tonal.music_prob = p1 / (p0 + p1);
                info.music_prob  = tonal.music_prob;

                /* This chunk of code deals with delayed decision. */
                psum = 1e-20f;
                /* Instantaneous probability of speech and music, with beta pre-applied. */
                speech0 = (float)Math.Pow(1 - frame_probs[0], beta);
                music0  = (float)Math.Pow(frame_probs[0], beta);
                if (tonal.count == 1)
                {
                    tonal.pspeech[0] = 0.5f;
                    tonal.pmusic[0]  = 0.5f;
                }

                /* Updated probability of having only speech (s0) or only music (m0),
                 *  before considering the new observation. */
                s0 = tonal.pspeech[0] + tonal.pspeech[1];
                m0 = tonal.pmusic[0] + tonal.pmusic[1];
                /* Updates s0 and m0 with instantaneous probability. */
                tonal.pspeech[0] = s0 * (1 - tau) * speech0;
                tonal.pmusic[0]  = m0 * (1 - tau) * music0;
                /* Propagate the transition probabilities */
                for (i = 1; i < OpusConstants.DETECT_SIZE - 1; i++)
                {
                    tonal.pspeech[i] = tonal.pspeech[i + 1] * speech0;
                    tonal.pmusic[i]  = tonal.pmusic[i + 1] * music0;
                }
                /* Probability that the latest frame is speech, when all the previous ones were music. */
                tonal.pspeech[OpusConstants.DETECT_SIZE - 1] = m0 * tau * speech0;
                /* Probability that the latest frame is music, when all the previous ones were speech. */
                tonal.pmusic[OpusConstants.DETECT_SIZE - 1] = s0 * tau * music0;

                /* Renormalise probabilities to 1 */
                for (i = 0; i < OpusConstants.DETECT_SIZE; i++)
                {
                    psum += tonal.pspeech[i] + tonal.pmusic[i];
                }
                psum = 1.0f / psum;
                for (i = 0; i < OpusConstants.DETECT_SIZE; i++)
                {
                    tonal.pspeech[i] *= psum;
                    tonal.pmusic[i]  *= psum;
                }
                psum = tonal.pmusic[0];
                for (i = 1; i < OpusConstants.DETECT_SIZE; i++)
                {
                    psum += tonal.pspeech[i];
                }

                /* Estimate our confidence in the speech/music decisions */
                if (frame_probs[1] > .75)
                {
                    if (tonal.music_prob > .9)
                    {
                        float adapt;
                        adapt = 1.0f / (++tonal.music_confidence_count);
                        tonal.music_confidence_count = Inlines.IMIN(tonal.music_confidence_count, 500);
                        tonal.music_confidence      += adapt * Inlines.MAX16(-.2f, frame_probs[0] - tonal.music_confidence);
                    }
                    if (tonal.music_prob < .1)
                    {
                        float adapt;
                        adapt = 1.0f / (++tonal.speech_confidence_count);
                        tonal.speech_confidence_count = Inlines.IMIN(tonal.speech_confidence_count, 500);
                        tonal.speech_confidence      += adapt * Inlines.MIN16(.2f, frame_probs[0] - tonal.speech_confidence);
                    }
                }
                else
                {
                    if (tonal.music_confidence_count == 0)
                    {
                        tonal.music_confidence = .9f;
                    }
                    if (tonal.speech_confidence_count == 0)
                    {
                        tonal.speech_confidence = .1f;
                    }
                }
            }
            if (tonal.last_music != ((tonal.music_prob > .5f) ? 1 : 0))
            {
                tonal.last_transition = 0;
            }
            tonal.last_music = (tonal.music_prob > .5f) ? 1 : 0;

            info.bandwidth = bandwidth;
            info.noisiness = frame_noisiness;
            info.valid     = 1;
        }