* AC-3 DSP utils
* Copyright (c) 2011 Justin Ruggles
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
+#include "ac3.h"
#include "ac3dsp.h"
static void ac3_exponent_min_c(uint8_t *exp, int num_reuse_blocks, int nb_coefs)
}
}
-av_cold void ff_ac3dsp_init(AC3DSPContext *c)
+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;
+
+ /* 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;
+ int band_end = FFMIN(ff_ac3_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 > ff_ac3_band_start_tab[band++]);
+}
+
+static int ac3_compute_mantissa_size_c(int mant_cnt[5], uint8_t *bap,
+ int nb_coefs)
+{
+ int bits, b, i;
+
+ bits = 0;
+ for (i = 0; i < nb_coefs; i++) {
+ b = bap[i];
+ if (b <= 4) {
+ // bap=1 to bap=4 will be counted in compute_mantissa_size_final
+ mant_cnt[b]++;
+ } else if (b <= 13) {
+ // bap=5 to bap=13 use (bap-1) bits
+ bits += b - 1;
+ } else {
+ // bap=14 uses 14 bits and bap=15 uses 16 bits
+ bits += (b == 14) ? 14 : 16;
+ }
+ }
+ return bits;
+}
+
+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->compute_mantissa_size = ac3_compute_mantissa_size_c;
+ if (ARCH_ARM)
+ ff_ac3dsp_init_arm(c, bit_exact);
if (HAVE_MMX)
- ff_ac3dsp_init_x86(c);
+ ff_ac3dsp_init_x86(c, bit_exact);
}
projects / ffmpeg / blobdiff