X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fac3dsp.c;h=98c73573cb2ea56d44cad85885b9813d63349041;hb=195c123cc87bb46efbadb48b2f756ae49bdb6774;hp=77250a351bc647d533abc4763d6c8e4016a96170;hpb=6d9f52b2cd760eacf6cc6b7d694b0b00d991f1de;p=ffmpeg

diff --git a/libavcodec/ac3dsp.c b/libavcodec/ac3dsp.c
index 77250a351bc..98c73573cb2 100644
--- a/libavcodec/ac3dsp.c
+++ b/libavcodec/ac3dsp.c
@@ -19,6 +19,7 @@
  * 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"
@@ -127,6 +128,47 @@ static void ac3_bit_alloc_calc_bap_c(int16_t *mask, int16_t *psd,
     } while (end > ff_ac3_band_start_tab[band++]);
 }
 
+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;
+    }
+}
+
 av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
 {
     c->ac3_exponent_min = ac3_exponent_min_c;
@@ -135,6 +177,9 @@ av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
     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;
 
     if (ARCH_ARM)
         ff_ac3dsp_init_arm(c, bit_exact);