diff options
| author | povaddict <povaddict@users.sourceforge.net> | 2010-02-10 02:16:44 +0300 |
|---|---|---|
| committer | povaddict <povaddict@users.sourceforge.net> | 2010-02-10 02:16:44 +0300 |
| commit | 726a91b12a7524e45e7a901c9e4883af5b1bffe6 (patch) | |
| tree | f5d25e3b2e84c92f4901280c73d5d3d7e6c3cd19 /src/filters/transform/MPCVideoDec/ffmpeg/libavcodec/ac3.c | |
| parent | 02183f6e47ad4ea1057de9950482f291f2ae4290 (diff) | |
Rename several directories to use MixedCase instead of lowercase.
They now mostly match the case used in #includes,
and they're consistent with the names of the .h files they contain.
git-svn-id: https://mpc-hc.svn.sourceforge.net/svnroot/mpc-hc/trunk@1648 10f7b99b-c216-0410-bff0-8a66a9350fd8
Diffstat (limited to 'src/filters/transform/MPCVideoDec/ffmpeg/libavcodec/ac3.c')
| -rw-r--r-- | src/filters/transform/MPCVideoDec/ffmpeg/libavcodec/ac3.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/src/filters/transform/MPCVideoDec/ffmpeg/libavcodec/ac3.c b/src/filters/transform/MPCVideoDec/ffmpeg/libavcodec/ac3.c new file mode 100644 index 000000000..255ec9081 --- /dev/null +++ b/src/filters/transform/MPCVideoDec/ffmpeg/libavcodec/ac3.c @@ -0,0 +1,281 @@ +/*
+ * Common code between the AC-3 encoder and decoder
+ * Copyright (c) 2000 Fabrice Bellard
+ *
+ * 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
+ */
+
+/**
+ * @file libavcodec/ac3.c
+ * Common code between the AC-3 encoder and decoder.
+ */
+
+#include "avcodec.h"
+#include "ac3.h"
+#include "get_bits.h"
+
+#if CONFIG_HARDCODED_TABLES
+
+/**
+ * Starting frequency coefficient bin for each critical band.
+ */
+static const uint8_t band_start_tab[51] = {
+ 0, 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, 31,
+ 34, 37, 40, 43, 46, 49, 55, 61, 67, 73,
+ 79, 85, 97, 109, 121, 133, 157, 181, 205, 229, 253
+};
+
+/**
+ * Maps each frequency coefficient bin to the critical band that contains it.
+ */
+static const uint8_t bin_to_band_tab[253] = {
+ 0,
+ 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, 28, 28, 29, 29, 29, 30, 30, 30,
+ 31, 31, 31, 32, 32, 32, 33, 33, 33, 34, 34, 34,
+ 35, 35, 35, 35, 35, 35, 36, 36, 36, 36, 36, 36,
+ 37, 37, 37, 37, 37, 37, 38, 38, 38, 38, 38, 38,
+ 39, 39, 39, 39, 39, 39, 40, 40, 40, 40, 40, 40,
+ 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41,
+ 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42,
+ 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43,
+ 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44,
+ 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45,
+ 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45, 45,
+ 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46,
+ 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46, 46,
+ 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47,
+ 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47, 47,
+ 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
+ 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
+ 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49,
+ 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49
+};
+
+#else /* CONFIG_HARDCODED_TABLES */
+static uint8_t band_start_tab[51];
+static uint8_t bin_to_band_tab[253];
+#endif
+
+static inline int calc_lowcomp1(int a, int b0, int b1, int c)
+{
+ if ((b0 + 256) == b1) {
+ a = c;
+ } else if (b0 > b1) {
+ a = FFMAX(a - 64, 0);
+ }
+ return a;
+}
+
+static inline int calc_lowcomp(int a, int b0, int b1, int bin)
+{
+ if (bin < 7) {
+ return calc_lowcomp1(a, b0, b1, 384);
+ } else if (bin < 20) {
+ return calc_lowcomp1(a, b0, b1, 320);
+ } else {
+ return FFMAX(a - 128, 0);
+ }
+}
+
+void ff_ac3_bit_alloc_calc_psd(int8_t *exp, int start, int end, int16_t *psd,
+ int16_t *band_psd)
+{
+ int bin, band;
+
+ /* exponent mapping to PSD */
+ for (bin = start; bin < end; bin++) {
+ psd[bin]=(3072 - (exp[bin] << 7));
+ }
+
+ /* PSD integration */
+ bin = start;
+ band = bin_to_band_tab[start];
+ do {
+ int v = psd[bin++];
+ int band_end = FFMIN(band_start_tab[band+1], end);
+ for (; bin < band_end; bin++) {
+ int max = FFMAX(v, psd[bin]);
+ /* logadd */
+ int adr = FFMIN(max - ((v + psd[bin] + 1) >> 1), 255);
+ v = max + ff_ac3_log_add_tab[adr];
+ }
+ band_psd[band++] = v;
+ } while (end > band_start_tab[band]);
+}
+
+int ff_ac3_bit_alloc_calc_mask(AC3BitAllocParameters *s, int16_t *band_psd,
+ int start, int end, int fast_gain, int is_lfe,
+ int dba_mode, int dba_nsegs, uint8_t *dba_offsets,
+ uint8_t *dba_lengths, uint8_t *dba_values,
+ int16_t *mask)
+{
+ int16_t excite[50]; /* excitation */
+ int band;
+ int band_start, band_end, begin, end1;
+ int lowcomp, fastleak, slowleak;
+
+ /* excitation function */
+ band_start = bin_to_band_tab[start];
+ band_end = bin_to_band_tab[end-1] + 1;
+
+ if (band_start == 0) {
+ lowcomp = 0;
+ lowcomp = calc_lowcomp1(lowcomp, band_psd[0], band_psd[1], 384);
+ excite[0] = band_psd[0] - fast_gain - lowcomp;
+ lowcomp = calc_lowcomp1(lowcomp, band_psd[1], band_psd[2], 384);
+ excite[1] = band_psd[1] - fast_gain - lowcomp;
+ begin = 7;
+ for (band = 2; band < 7; band++) {
+ if (!(is_lfe && band == 6))
+ lowcomp = calc_lowcomp1(lowcomp, band_psd[band], band_psd[band+1], 384);
+ fastleak = band_psd[band] - fast_gain;
+ slowleak = band_psd[band] - s->slow_gain;
+ excite[band] = fastleak - lowcomp;
+ if (!(is_lfe && band == 6)) {
+ if (band_psd[band] <= band_psd[band+1]) {
+ begin = band + 1;
+ break;
+ }
+ }
+ }
+
+ end1 = FFMIN(band_end, 22);
+ for (band = begin; band < end1; band++) {
+ if (!(is_lfe && band == 6))
+ lowcomp = calc_lowcomp(lowcomp, band_psd[band], band_psd[band+1], band);
+ fastleak = FFMAX(fastleak - s->fast_decay, band_psd[band] - fast_gain);
+ slowleak = FFMAX(slowleak - s->slow_decay, band_psd[band] - s->slow_gain);
+ excite[band] = FFMAX(fastleak - lowcomp, slowleak);
+ }
+ begin = 22;
+ } else {
+ /* coupling channel */
+ begin = band_start;
+ fastleak = (s->cpl_fast_leak << 8) + 768;
+ slowleak = (s->cpl_slow_leak << 8) + 768;
+ }
+
+ for (band = begin; band < band_end; band++) {
+ fastleak = FFMAX(fastleak - s->fast_decay, band_psd[band] - fast_gain);
+ slowleak = FFMAX(slowleak - s->slow_decay, band_psd[band] - s->slow_gain);
+ excite[band] = FFMAX(fastleak, slowleak);
+ }
+
+ /* compute masking curve */
+
+ for (band = band_start; band < band_end; band++) {
+ int tmp = s->db_per_bit - band_psd[band];
+ if (tmp > 0) {
+ excite[band] += tmp >> 2;
+ }
+ mask[band] = FFMAX(ff_ac3_hearing_threshold_tab[band >> s->sr_shift][s->sr_code], excite[band]);
+ }
+
+ /* delta bit allocation */
+
+ if (dba_mode == DBA_REUSE || dba_mode == DBA_NEW) {
+ int i, seg, delta;
+ if (dba_nsegs >= 8)
+ return -1;
+ band = 0;
+ for (seg = 0; seg < dba_nsegs; seg++) {
+ band += dba_offsets[seg];
+ if (band >= 50 || dba_lengths[seg] > 50-band)
+ return -1;
+ if (dba_values[seg] >= 4) {
+ delta = (dba_values[seg] - 3) << 7;
+ } else {
+ delta = (dba_values[seg] - 4) << 7;
+ }
+ for (i = 0; i < dba_lengths[seg]; i++) {
+ mask[band++] += delta;
+ }
+ }
+ }
+ return 0;
+}
+
+void ff_ac3_bit_alloc_calc_bap(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;
+
+ /* special case, if snr offset is -960, set all bap's to zero */
+ if (snr_offset == -960) {
+ memset(bap, 0, 256);
+ return;
+ }
+
+ bin = start;
+ band = bin_to_band_tab[start];
+ do {
+ int m = (FFMAX(mask[band] - snr_offset - floor, 0) & 0x1FE0) + floor;
+ int band_end = FFMIN(band_start_tab[band+1], end);
+ for (; bin < band_end; bin++) {
+ int address = av_clip((psd[bin] - m) >> 5, 0, 63);
+ bap[bin] = bap_tab[address];
+ }
+ } while (end > band_start_tab[band++]);
+}
+
+/* AC-3 bit allocation. The algorithm is the one described in the AC-3
+ spec. */
+void ac3_parametric_bit_allocation(AC3BitAllocParameters *s, uint8_t *bap,
+ int8_t *exp, int start, int end,
+ int snr_offset, int fast_gain, int is_lfe,
+ int dba_mode, int dba_nsegs,
+ uint8_t *dba_offsets, uint8_t *dba_lengths,
+ uint8_t *dba_values)
+{
+ int16_t psd[256]; /* scaled exponents */
+ int16_t band_psd[50]; /* interpolated exponents */
+ int16_t mask[50]; /* masking value */
+
+ ff_ac3_bit_alloc_calc_psd(exp, start, end, psd, band_psd);
+
+ ff_ac3_bit_alloc_calc_mask(s, band_psd, start, end, fast_gain, is_lfe,
+ dba_mode, dba_nsegs, dba_offsets, dba_lengths,
+ dba_values, mask);
+
+ ff_ac3_bit_alloc_calc_bap(mask, psd, start, end, snr_offset, s->floor,
+ ff_ac3_bap_tab, bap);
+}
+
+/**
+ * Initializes some tables.
+ * note: This function must remain thread safe because it is called by the
+ * AVParser init code.
+ */
+av_cold void ac3_common_init(void)
+{
+#if !CONFIG_HARDCODED_TABLES
+ /* compute bndtab and masktab from bandsz */
+ int bin = 0, band;
+ for (band = 0; band < 50; band++) {
+ int band_end = bin + ff_ac3_critical_band_size_tab[band];
+ band_start_tab[band] = bin;
+ while (bin < band_end)
+ bin_to_band_tab[bin++] = band;
+ }
+ band_start_tab[50] = bin;
+#endif /* !CONFIG_HARDCODED_TABLES */
+}
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