ac3enc: allow new coupling coordinates to be sent independently for each

channel.

libavcodec/ac3enc.c

@@ -864,9 +864,9 @@ static void count_frame_bits(AC3EncodeContext *s)
         if (block->cpl_in_use) {
             for (ch = 1; ch <= s->fbw_channels; ch++) {
                 if (block->channel_in_cpl[ch]) {
-                    if (!s->eac3 || block->new_cpl_coords != 2)
+                    if (!s->eac3 || block->new_cpl_coords[ch] != 2)
                         frame_bits++;
-                    if (block->new_cpl_coords) {
+                    if (block->new_cpl_coords[ch]) {
                         frame_bits += 2;
                         frame_bits += (4 + 4) * s->num_cpl_bands;
                     }
@@ -1394,9 +1394,9 @@ static void output_audio_block(AC3EncodeContext *s, int blk)
     if (block->cpl_in_use) {
         for (ch = 1; ch <= s->fbw_channels; ch++) {
             if (block->channel_in_cpl[ch]) {
-                if (!s->eac3 || block->new_cpl_coords != 2)
-                    put_bits(&s->pb, 1, block->new_cpl_coords);
-                if (block->new_cpl_coords) {
+                if (!s->eac3 || block->new_cpl_coords[ch] != 2)
+                    put_bits(&s->pb, 1, block->new_cpl_coords[ch]);
+                if (block->new_cpl_coords[ch]) {
                     put_bits(&s->pb, 2, block->cpl_master_exp[ch]);
                     for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
                         put_bits(&s->pb, 4, block->cpl_coord_exp [ch][bnd]);

libavcodec/ac3enc.h

@@ -123,7 +123,7 @@ typedef struct AC3Block {
     int      cpl_in_use;                        ///< coupling in use for this block     (cplinu)
     uint8_t  channel_in_cpl[AC3_MAX_CHANNELS];  ///< channel in coupling                (chincpl)
     int      num_cpl_channels;                  ///< number of channels in coupling
-    uint8_t  new_cpl_coords;                    ///< send new coupling coordinates      (cplcoe)
+    uint8_t  new_cpl_coords[AC3_MAX_CHANNELS];  ///< send new coupling coordinates      (cplcoe)
     uint8_t  cpl_master_exp[AC3_MAX_CHANNELS];  ///< coupling coord master exponents    (mstrcplco)
     int      new_snr_offsets;                   ///< send new SNR offsets
     int      new_cpl_leak;                      ///< send new coupling leak info

libavcodec/ac3enc_template.c

@@ -206,9 +206,10 @@ static void apply_channel_coupling(AC3EncodeContext *s)
     for (blk = 0; blk < s->num_blocks; blk++) {
         AC3Block *block  = &s->blocks[blk];
         AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
-        int new_coords = 0;
         CoefSumType coord_diff[AC3_MAX_CHANNELS] = {0,};
 
+        memset(block->new_cpl_coords, 0, sizeof(block->new_cpl_coords));
+
         if (block->cpl_in_use) {
             /* calculate coupling coordinates for all blocks and calculate the
                average difference between coordinates in successive blocks */
@@ -233,28 +234,18 @@ static void apply_channel_coupling(AC3EncodeContext *s)
              * using coupling has changed from the previous block, or the
              * coordinate difference from the last block for any channel is
              * greater than a threshold value. */
-            if (blk == 0) {
-                new_coords = 1;
-            } else if (!block0->cpl_in_use) {
-                new_coords = 1;
+            if (blk == 0 || !block0->cpl_in_use) {
+                for (ch = 1; ch <= s->fbw_channels; ch++)
+                    block->new_cpl_coords[ch] = 1;
             } else {
                 for (ch = 1; ch <= s->fbw_channels; ch++) {
-                    if (block->channel_in_cpl[ch] && !block0->channel_in_cpl[ch]) {
-                        new_coords = 1;
-                        break;
-                    }
-                }
-                if (!new_coords) {
-                    for (ch = 1; ch <= s->fbw_channels; ch++) {
-                        if (block->channel_in_cpl[ch] && coord_diff[ch] > 0.04) {
-                            new_coords = 1;
-                            break;
-                        }
+                    if ((block->channel_in_cpl[ch] && !block0->channel_in_cpl[ch]) ||
+                        (block->channel_in_cpl[ch] && coord_diff[ch] > 0.03)) {
+                        block->new_cpl_coords[ch] = 1;
                     }
                 }
             }
         }
-        block->new_cpl_coords = new_coords;
     }
 
     /* calculate final coupling coordinates, taking into account reusing of
@@ -262,8 +253,7 @@ static void apply_channel_coupling(AC3EncodeContext *s)
     for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
         blk = 0;
         while (blk < s->num_blocks) {
-            int blk1;
-            CoefSumType energy_cpl;
+            int av_uninit(blk1);
             AC3Block *block  = &s->blocks[blk];
 
             if (!block->cpl_in_use) {
@@ -271,23 +261,18 @@ static void apply_channel_coupling(AC3EncodeContext *s)
                 continue;
             }
 
-            energy_cpl = energy[blk][CPL_CH][bnd];
-            blk1 = blk+1;
-            while (!s->blocks[blk1].new_cpl_coords && blk1 < s->num_blocks) {
-                if (s->blocks[blk1].cpl_in_use)
-                    energy_cpl += energy[blk1][CPL_CH][bnd];
-                blk1++;
-            }
-
             for (ch = 1; ch <= s->fbw_channels; ch++) {
-                CoefType energy_ch;
+                CoefSumType energy_ch, energy_cpl;
                 if (!block->channel_in_cpl[ch])
                     continue;
+                energy_cpl = energy[blk][CPL_CH][bnd];
                 energy_ch = energy[blk][ch][bnd];
                 blk1 = blk+1;
-                while (!s->blocks[blk1].new_cpl_coords && blk1 < s->num_blocks) {
-                    if (s->blocks[blk1].cpl_in_use)
+                while (!s->blocks[blk1].new_cpl_coords[ch] && blk1 < s->num_blocks) {
+                    if (s->blocks[blk1].cpl_in_use) {
+                        energy_cpl += energy[blk1][CPL_CH][bnd];
                         energy_ch += energy[blk1][ch][bnd];
+                    }
                     blk1++;
                 }
                 cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
@@ -299,7 +284,7 @@ static void apply_channel_coupling(AC3EncodeContext *s)
     /* calculate exponents/mantissas for coupling coordinates */
     for (blk = 0; blk < s->num_blocks; blk++) {
         AC3Block *block = &s->blocks[blk];
-        if (!block->cpl_in_use || !block->new_cpl_coords)
+        if (!block->cpl_in_use)
             continue;
 
         clip_coefficients(&s->dsp, cpl_coords[blk][1], s->fbw_channels * 16);
@@ -313,6 +298,9 @@ static void apply_channel_coupling(AC3EncodeContext *s)
         for (ch = 1; ch <= s->fbw_channels; ch++) {
             int bnd, min_exp, max_exp, master_exp;
 
+            if (!block->new_cpl_coords[ch])
+                continue;
+
             /* determine master exponent */
             min_exp = max_exp = block->cpl_coord_exp[ch][0];
             for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {

libavcodec/eac3enc.c

@@ -99,7 +99,7 @@ void ff_eac3_set_cpl_states(AC3EncodeContext *s)
         for (ch = 1; ch <= s->fbw_channels; ch++) {
             if (block->channel_in_cpl[ch]) {
                 if (first_cpl_coords[ch]) {
-                    block->new_cpl_coords = 2;
+                    block->new_cpl_coords[ch] = 2;
                     first_cpl_coords[ch]  = 0;
                 }
             } else {