making act segmenter

1 files changed, 263 insertions, 0 deletions

diff --git a/ffmpeg/libavcodec/ac3dsp.c b/ffmpeg/libavcodec/ac3dsp.c
new file mode 100644
index 0000000..6df3a68
--- /dev/null
+++ b/ffmpeg/libavcodec/ac3dsp.c
@@ -0,0 +1,263 @@
+/*
+ * AC-3 DSP utils
+ * Copyright (c) 2011 Justin Ruggles
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/avassert.h"
+#include "avcodec.h"
+#include "ac3.h"
+#include "ac3dsp.h"
+#include "mathops.h"
+
+static void ac3_exponent_min_c(uint8_t *exp, int num_reuse_blocks, int nb_coefs)
+{
+    int blk, i;
+
+    if (!num_reuse_blocks)
+        return;
+
+    for (i = 0; i < nb_coefs; i++) {
+        uint8_t min_exp = *exp;
+        uint8_t *exp1 = exp + 256;
+        for (blk = 0; blk < num_reuse_blocks; blk++) {
+            uint8_t next_exp = *exp1;
+            if (next_exp < min_exp)
+                min_exp = next_exp;
+            exp1 += 256;
+        }
+        *exp++ = min_exp;
+    }
+}
+
+static int ac3_max_msb_abs_int16_c(const int16_t *src, int len)
+{
+    int i, v = 0;
+    for (i = 0; i < len; i++)
+        v |= abs(src[i]);
+    return v;
+}
+
+static void ac3_lshift_int16_c(int16_t *src, unsigned int len,
+                               unsigned int shift)
+{
+    uint32_t *src32 = (uint32_t *)src;
+    const uint32_t mask = ~(((1 << shift) - 1) << 16);
+    int i;
+    len >>= 1;
+    for (i = 0; i < len; i += 8) {
+        src32[i  ] = (src32[i  ] << shift) & mask;
+        src32[i+1] = (src32[i+1] << shift) & mask;
+        src32[i+2] = (src32[i+2] << shift) & mask;
+        src32[i+3] = (src32[i+3] << shift) & mask;
+        src32[i+4] = (src32[i+4] << shift) & mask;
+        src32[i+5] = (src32[i+5] << shift) & mask;
+        src32[i+6] = (src32[i+6] << shift) & mask;
+        src32[i+7] = (src32[i+7] << shift) & mask;
+    }
+}
+
+static void ac3_rshift_int32_c(int32_t *src, unsigned int len,
+                               unsigned int shift)
+{
+    do {
+        *src++ >>= shift;
+        *src++ >>= shift;
+        *src++ >>= shift;
+        *src++ >>= shift;
+        *src++ >>= shift;
+        *src++ >>= shift;
+        *src++ >>= shift;
+        *src++ >>= shift;
+        len -= 8;
+    } while (len > 0);
+}
+
+static void float_to_fixed24_c(int32_t *dst, const float *src, unsigned int len)
+{
+    const float scale = 1 << 24;
+    do {
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        *dst++ = lrintf(*src++ * scale);
+        len -= 8;
+    } while (len > 0);
+}
+
+static void ac3_bit_alloc_calc_bap_c(int16_t *mask, int16_t *psd,
+                                     int start, int end,
+                                     int snr_offset, int floor,
+                                     const uint8_t *bap_tab, uint8_t *bap)
+{
+    int bin, band, band_end;
+
+    /* special case, if snr offset is -960, set all bap's to zero */
+    if (snr_offset == -960) {
+        memset(bap, 0, AC3_MAX_COEFS);
+        return;
+    }
+
+    bin  = start;
+    band = ff_ac3_bin_to_band_tab[start];
+    do {
+        int m = (FFMAX(mask[band] - snr_offset - floor, 0) & 0x1FE0) + floor;
+        band_end = ff_ac3_band_start_tab[++band];
+        band_end = FFMIN(band_end, end);
+
+        for (; bin < band_end; bin++) {
+            int address = av_clip((psd[bin] - m) >> 5, 0, 63);
+            bap[bin] = bap_tab[address];
+        }
+    } while (end > band_end);
+}
+
+static void ac3_update_bap_counts_c(uint16_t mant_cnt[16], uint8_t *bap,
+                                    int len)
+{
+    while (len-- > 0)
+        mant_cnt[bap[len]]++;
+}
+
+DECLARE_ALIGNED(16, const uint16_t, ff_ac3_bap_bits)[16] = {
+    0,  0,  0,  3,  0,  4,  5,  6,  7,  8,  9, 10, 11, 12, 14, 16
+};
+
+static int ac3_compute_mantissa_size_c(uint16_t mant_cnt[6][16])
+{
+    int blk, bap;
+    int bits = 0;
+
+    for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+        // bap=1 : 3 mantissas in 5 bits
+        bits += (mant_cnt[blk][1] / 3) * 5;
+        // bap=2 : 3 mantissas in 7 bits
+        // bap=4 : 2 mantissas in 7 bits
+        bits += ((mant_cnt[blk][2] / 3) + (mant_cnt[blk][4] >> 1)) * 7;
+        // bap=3 : 1 mantissa in 3 bits
+        bits += mant_cnt[blk][3] * 3;
+        // bap=5 to 15 : get bits per mantissa from table
+        for (bap = 5; bap < 16; bap++)
+            bits += mant_cnt[blk][bap] * ff_ac3_bap_bits[bap];
+    }
+    return bits;
+}
+
+static void ac3_extract_exponents_c(uint8_t *exp, int32_t *coef, int nb_coefs)
+{
+    int i;
+
+    for (i = 0; i < nb_coefs; i++) {
+        int v = abs(coef[i]);
+        exp[i] = v ? 23 - av_log2(v) : 24;
+    }
+}
+
+static void ac3_sum_square_butterfly_int32_c(int64_t sum[4],
+                                             const int32_t *coef0,
+                                             const int32_t *coef1,
+                                             int len)
+{
+    int i;
+
+    sum[0] = sum[1] = sum[2] = sum[3] = 0;
+
+    for (i = 0; i < len; i++) {
+        int lt = coef0[i];
+        int rt = coef1[i];
+        int md = lt + rt;
+        int sd = lt - rt;
+        MAC64(sum[0], lt, lt);
+        MAC64(sum[1], rt, rt);
+        MAC64(sum[2], md, md);
+        MAC64(sum[3], sd, sd);
+    }
+}
+
+static void ac3_sum_square_butterfly_float_c(float sum[4],
+                                             const float *coef0,
+                                             const float *coef1,
+                                             int len)
+{
+    int i;
+
+    sum[0] = sum[1] = sum[2] = sum[3] = 0;
+
+    for (i = 0; i < len; i++) {
+        float lt = coef0[i];
+        float rt = coef1[i];
+        float md = lt + rt;
+        float sd = lt - rt;
+        sum[0] += lt * lt;
+        sum[1] += rt * rt;
+        sum[2] += md * md;
+        sum[3] += sd * sd;
+    }
+}
+
+static void ac3_downmix_c(float **samples, float (*matrix)[2],
+                          int out_ch, int in_ch, int len)
+{
+    int i, j;
+    float v0, v1;
+    if (out_ch == 2) {
+        for (i = 0; i < len; i++) {
+            v0 = v1 = 0.0f;
+            for (j = 0; j < in_ch; j++) {
+                v0 += samples[j][i] * matrix[j][0];
+                v1 += samples[j][i] * matrix[j][1];
+            }
+            samples[0][i] = v0;
+            samples[1][i] = v1;
+        }
+    } else if (out_ch == 1) {
+        for (i = 0; i < len; i++) {
+            v0 = 0.0f;
+            for (j = 0; j < in_ch; j++)
+                v0 += samples[j][i] * matrix[j][0];
+            samples[0][i] = v0;
+        }
+    }
+}
+
+av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
+{
+    c->ac3_exponent_min = ac3_exponent_min_c;
+    c->ac3_max_msb_abs_int16 = ac3_max_msb_abs_int16_c;
+    c->ac3_lshift_int16 = ac3_lshift_int16_c;
+    c->ac3_rshift_int32 = ac3_rshift_int32_c;
+    c->float_to_fixed24 = float_to_fixed24_c;
+    c->bit_alloc_calc_bap = ac3_bit_alloc_calc_bap_c;
+    c->update_bap_counts = ac3_update_bap_counts_c;
+    c->compute_mantissa_size = ac3_compute_mantissa_size_c;
+    c->extract_exponents = ac3_extract_exponents_c;
+    c->sum_square_butterfly_int32 = ac3_sum_square_butterfly_int32_c;
+    c->sum_square_butterfly_float = ac3_sum_square_butterfly_float_c;
+    c->downmix = ac3_downmix_c;
+
+    if (ARCH_ARM)
+        ff_ac3dsp_init_arm(c, bit_exact);
+    if (ARCH_X86)
+        ff_ac3dsp_init_x86(c, bit_exact);
+    if (ARCH_MIPS)
+        ff_ac3dsp_init_mips(c, bit_exact);
+}