[FFmpeg-devel] [PATCH 1/3] avcodec/aacsbr: Split the env_facs table

Michael Niedermayer michaelni at gmx.at
Thu Nov 19 14:17:50 CET 2015


From: Michael Niedermayer <michael at niedermayer.cc>

This also removes a #ifdef and special case for the fixed point case

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/aacsbr.c          |    6 +++---
 libavcodec/aacsbr_fixed.c    |    6 +++---
 libavcodec/aacsbr_template.c |   42 ++++++++----------------------------------
 3 files changed, 14 insertions(+), 40 deletions(-)

diff --git a/libavcodec/aacsbr.c b/libavcodec/aacsbr.c
index f7c9b22..d1e3a91 100644
--- a/libavcodec/aacsbr.c
+++ b/libavcodec/aacsbr.c
@@ -79,8 +79,8 @@ static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
         float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
         for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
             for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
-                float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
-                float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
+                float temp1 = exp2f(sbr->data[0].env_facs_q[e][k] * alpha + 7.0f);
+                float temp2 = exp2f((pan_offset - sbr->data[1].env_facs_q[e][k]) * alpha);
                 float fac;
                 if (temp1 > 1E20) {
                     av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
@@ -108,7 +108,7 @@ static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
             for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
                 for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++){
                     sbr->data[ch].env_facs[e][k] =
-                        exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
+                        exp2f(alpha * sbr->data[ch].env_facs_q[e][k] + 6.0f);
                     if (sbr->data[ch].env_facs[e][k] > 1E20) {
                         av_log(NULL, AV_LOG_ERROR, "envelope scalefactor overflow in dequant\n");
                         sbr->data[ch].env_facs[e][k] = 1;
diff --git a/libavcodec/aacsbr_fixed.c b/libavcodec/aacsbr_fixed.c
index 6ec39c1..7194b03 100644
--- a/libavcodec/aacsbr_fixed.c
+++ b/libavcodec/aacsbr_fixed.c
@@ -163,7 +163,7 @@ static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
             for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
                 SoftFloat temp1, temp2, fac;
 
-                temp1.exp = sbr->data[0].env_facs[e][k].mant * alpha + 14;
+                temp1.exp = sbr->data[0].env_facs_q[e][k] * alpha + 14;
                 if (temp1.exp & 1)
                   temp1.mant = 759250125;
                 else
@@ -174,7 +174,7 @@ static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
                     temp1 = FLOAT_1;
                 }
 
-                temp2.exp = (pan_offset - sbr->data[1].env_facs[e][k].mant) * alpha;
+                temp2.exp = (pan_offset - sbr->data[1].env_facs_q[e][k]) * alpha;
                 if (temp2.exp & 1)
                   temp2.mant = 759250125;
                 else
@@ -210,7 +210,7 @@ static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
                 for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++){
                     SoftFloat temp1;
 
-                    temp1.exp = alpha * sbr->data[ch].env_facs[e][k].mant + 12;
+                    temp1.exp = alpha * sbr->data[ch].env_facs_q[e][k] + 12;
                     if (temp1.exp & 1)
                         temp1.mant = 759250125;
                     else
diff --git a/libavcodec/aacsbr_template.c b/libavcodec/aacsbr_template.c
index 7772b68..748877d 100644
--- a/libavcodec/aacsbr_template.c
+++ b/libavcodec/aacsbr_template.c
@@ -831,59 +831,33 @@ static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
         }
     }
 
-#if USE_FIXED
     for (i = 0; i < ch_data->bs_num_env; i++) {
         if (ch_data->bs_df_env[i]) {
             // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
             if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
-                    ch_data->env_facs[i + 1][j].mant = ch_data->env_facs[i][j].mant + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
+                    ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
             } else if (ch_data->bs_freq_res[i + 1]) {
                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
                     k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
-                    ch_data->env_facs[i + 1][j].mant = ch_data->env_facs[i][k].mant + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
+                    ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
                 }
             } else {
                 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
                     k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
-                    ch_data->env_facs[i + 1][j].mant = ch_data->env_facs[i][k].mant + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
+                    ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
                 }
             }
         } else {
-            ch_data->env_facs[i + 1][0].mant = delta * get_bits(gb, bits); // bs_env_start_value_balance
+            ch_data->env_facs_q[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
             for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
-                ch_data->env_facs[i + 1][j].mant = ch_data->env_facs[i + 1][j - 1].mant + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
+                ch_data->env_facs_q[i + 1][j] = ch_data->env_facs_q[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
         }
     }
-#else
-    for (i = 0; i < ch_data->bs_num_env; i++) {
-        if (ch_data->bs_df_env[i]) {
-            // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
-            if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
-                for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
-                    ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
-            } else if (ch_data->bs_freq_res[i + 1]) {
-                for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
-                    k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
-                    ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
-                }
-            } else {
-                for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
-                    k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
-                    ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
-                }
-            }
-        } else {
-            ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
-            for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
-                ch_data->env_facs[i + 1][j] = ch_data->env_facs[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
-        }
-    }
-#endif /* USE_FIXED */
 
-    //assign 0th elements of env_facs from last elements
-    memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
-           sizeof(ch_data->env_facs[0]));
+    //assign 0th elements of env_facs_q from last elements
+    memcpy(ch_data->env_facs_q[0], ch_data->env_facs_q[ch_data->bs_num_env],
+           sizeof(ch_data->env_facs_q[0]));
 }
 
 static int read_sbr_noise(AACContext *ac, SpectralBandReplication *sbr, GetBitContext *gb,
-- 
1.7.9.5



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