Moves VBR calculations to a separate function.

Does not change the behaviour of the VBR code in most cases. The only
exception is that the VBR offset is now taken into accound in the base_rate,
which will have a (very minor) impact on CVBR at low rate.

1 files changed, 108 insertions, 84 deletions

diff --git a/celt/celt_encoder.c b/celt/celt_encoder.c
index 21ad4f8b..37697d95 100644
--- a/celt/celt_encoder.c
+++ b/celt/celt_encoder.c
@@ -1111,6 +1111,108 @@ static int run_prefilter(CELTEncoder *st, celt_sig *in, celt_sig *prefilter_mem,
    return pf_on;
 }
 
+static int compute_vbr(const CELTMode *mode, AnalysisInfo *analysis, opus_int32 base_target,
+      int LM, opus_int32 bitrate, int lastCodedBands, int C, int intensity,
+      int constrained_vbr, opus_val16 stereo_saving, int tot_boost,
+      opus_val16 tf_estimate, int pitch_change, opus_val16 maxDepth,
+      int variable_duration, int lfe, int has_surround_mask, opus_val16 surround_masking)
+{
+   /* The target rate in 8th bits per frame */
+   opus_int32 target;
+   int coded_bins;
+   int coded_bands;
+   int tf_calibration;
+   int nbEBands;
+   const opus_int16 *eBands;
+
+   nbEBands = mode->nbEBands;
+   eBands = mode->eBands;
+
+   coded_bands = lastCodedBands ? lastCodedBands : nbEBands;
+   coded_bins = eBands[coded_bands]<<LM;
+   if (C==2)
+      coded_bins += eBands[IMIN(intensity, coded_bands)]<<LM;
+
+   target = base_target;
+
+   /*printf("%f %f %f %f %d %d ", st->analysis.activity, st->analysis.tonality, tf_estimate, st->stereo_saving, tot_boost, coded_bands);*/
+#ifndef FIXED_POINT
+   if (analysis->valid && analysis->activity<.4)
+      target -= (opus_int32)((coded_bins<<BITRES)*(.4f-analysis->activity));
+#endif
+   /* Stereo savings */
+   if (C==2)
+   {
+      int coded_stereo_bands;
+      int coded_stereo_dof;
+      opus_val16 max_frac;
+      coded_stereo_bands = IMIN(intensity, coded_bands);
+      coded_stereo_dof = (eBands[coded_stereo_bands]<<LM)-coded_stereo_bands;
+      /* Maximum fraction of the bits we can save if the signal is mono. */
+      max_frac = DIV32_16(MULT16_16(QCONST16(0.8f, 15), coded_stereo_dof), coded_bins);
+      /*printf("%d %d %d ", coded_stereo_dof, coded_bins, tot_boost);*/
+      target -= (opus_int32)MIN32(MULT16_32_Q15(max_frac,target),
+                      SHR32(MULT16_16(stereo_saving-QCONST16(0.1f,8),(coded_stereo_dof<<BITRES)),8));
+   }
+   /* Boost the rate according to dynalloc (minus the dynalloc average for calibration). */
+   target += tot_boost-(16<<LM);
+   /* Apply transient boost, compensating for average boost. */
+   tf_calibration = variable_duration ? QCONST16(0.02f,14) : QCONST16(0.04f,14);
+   target += (opus_int32)SHL32(MULT16_32_Q15(tf_estimate-tf_calibration, target),1);
+
+#ifndef FIXED_POINT
+   /* Apply tonality boost */
+   if (analysis->valid) {
+      opus_int32 tonal_target;
+      float tonal;
+
+      /* Tonality boost (compensating for the average). */
+      tonal = MAX16(0.f,analysis->tonality-.15f)-0.09f;
+      tonal_target = target + (opus_int32)((coded_bins<<BITRES)*1.2f*tonal);
+      if (pitch_change)
+         tonal_target +=  (opus_int32)((coded_bins<<BITRES)*.8f);
+      /*printf("%f %f ", st->analysis.tonality, tonal);*/
+      target = tonal_target;
+   }
+#endif
+
+   if (has_surround_mask&&!lfe)
+   {
+      opus_int32 surround_target = target + SHR32(MULT16_16(surround_masking,coded_bins<<BITRES), DB_SHIFT);
+      /*printf("%f %d %d %d %d %d %d ", surround_masking, coded_bins, st->end, st->intensity, surround_target, target, st->bitrate);*/
+      target = IMAX(target/4, surround_target);
+   }
+
+   {
+      opus_int32 floor_depth;
+      int bins;
+      bins = eBands[nbEBands-2]<<LM;
+      /*floor_depth = SHR32(MULT16_16((C*bins<<BITRES),celt_log2(SHL32(MAX16(1,sample_max),13))), DB_SHIFT);*/
+      floor_depth = (opus_int32)SHR32(MULT16_16((C*bins<<BITRES),maxDepth), DB_SHIFT);
+      floor_depth = IMAX(floor_depth, target>>2);
+      target = IMIN(target, floor_depth);
+      /*printf("%f %d\n", maxDepth, floor_depth);*/
+   }
+
+   if ((!has_surround_mask||lfe) && (constrained_vbr || bitrate<64000))
+   {
+      opus_val16 rate_factor;
+#ifdef FIXED_POINT
+      rate_factor = MAX16(0,(bitrate-32000));
+#else
+      rate_factor = MAX16(0,(1.f/32768)*(bitrate-32000));
+#endif
+      if (constrained_vbr)
+         rate_factor = MIN16(rate_factor, QCONST16(0.67f, 15));
+      target = base_target + (opus_int32)MULT16_32_Q15(rate_factor, target-base_target);
+
+   }
+   /* Don't allow more than doubling the rate */
+   target = IMIN(2*base_target, target);
+
+   return target;
+}
+
 int celt_encode_with_ec(CELTEncoder * OPUS_RESTRICT st, const opus_val16 * pcm, int frame_size, unsigned char *compressed, int nbCompressedBytes, ec_enc *enc)
 {
    int i, c, N;
@@ -1628,98 +1730,20 @@ int celt_encode_with_ec(CELTEncoder * OPUS_RESTRICT st, const opus_val16 * pcm,
      /* The target rate in 8th bits per frame */
      opus_int32 target, base_target;
      opus_int32 min_allowed;
-     int coded_bins;
-     int coded_bands;
-     int tf_calibration;
      int lm_diff = mode->maxLM - LM;
-     coded_bands = st->lastCodedBands ? st->lastCodedBands : nbEBands;
-     coded_bins = eBands[coded_bands]<<LM;
-     if (C==2)
-        coded_bins += eBands[IMIN(st->intensity, coded_bands)]<<LM;
 
      /* Don't attempt to use more than 510 kb/s, even for frames smaller than 20 ms.
         The CELT allocator will just not be able to use more than that anyway. */
      nbCompressedBytes = IMIN(nbCompressedBytes,1275>>(3-LM));
-     target = vbr_rate - ((40*C+20)<<BITRES);
-     base_target = target;
+     base_target = vbr_rate - ((40*C+20)<<BITRES);
 
      if (st->constrained_vbr)
-        target += (st->vbr_offset>>lm_diff);
-
-     /*printf("%f %f %f %f %d %d ", st->analysis.activity, st->analysis.tonality, tf_estimate, st->stereo_saving, tot_boost, coded_bands);*/
-#ifndef FIXED_POINT
-     if (st->analysis.valid && st->analysis.activity<.4)
-        target -= (opus_int32)((coded_bins<<BITRES)*(.4f-st->analysis.activity));
-#endif
-     /* Stereo savings */
-     if (C==2)
-     {
-        int coded_stereo_bands;
-        int coded_stereo_dof;
-        opus_val16 max_frac;
-        coded_stereo_bands = IMIN(st->intensity, coded_bands);
-        coded_stereo_dof = (eBands[coded_stereo_bands]<<LM)-coded_stereo_bands;
-        /* Maximum fraction of the bits we can save if the signal is mono. */
-        max_frac = DIV32_16(MULT16_16(QCONST16(0.8f, 15), coded_stereo_dof), coded_bins);
-        /*printf("%d %d %d ", coded_stereo_dof, coded_bins, tot_boost);*/
-        target -= (opus_int32)MIN32(MULT16_32_Q15(max_frac,target),
-                        SHR32(MULT16_16(st->stereo_saving-QCONST16(0.1f,8),(coded_stereo_dof<<BITRES)),8));
-     }
-     /* Boost the rate according to dynalloc (minus the dynalloc average for calibration). */
-     target += tot_boost-(16<<LM);
-     /* Apply transient boost, compensating for average boost. */
-     tf_calibration = st->variable_duration ? QCONST16(0.02f,14) : QCONST16(0.04f,14);
-     target += (opus_int32)SHL32(MULT16_32_Q15(tf_estimate-tf_calibration, target),1);
-
-#ifndef FIXED_POINT
-     /* Apply tonality boost */
-     if (st->analysis.valid) {
-        opus_int32 tonal_target;
-        float tonal;
-
-        /* Tonality boost (compensating for the average). */
-        tonal = MAX16(0.f,st->analysis.tonality-.15f)-0.09f;
-        tonal_target = target + (opus_int32)((coded_bins<<BITRES)*1.2f*tonal);
-        if (pitch_change)
-           tonal_target +=  (opus_int32)((coded_bins<<BITRES)*.8f);
-        /*printf("%f %f ", st->analysis.tonality, tonal);*/
-        target = tonal_target;
-     }
-#endif
-
-     if (st->energy_mask&&!st->lfe)
-     {
-        opus_int32 surround_target = target + SHR32(MULT16_16(surround_masking,coded_bins<<BITRES), DB_SHIFT);
-        /*printf("%f %d %d %d %d %d %d ", surround_masking, coded_bins, st->end, st->intensity, surround_target, target, st->bitrate);*/
-        target = IMAX(target/4, surround_target);
-     }
-
-     {
-        opus_int32 floor_depth;
-        int bins;
-        bins = eBands[nbEBands-2]<<LM;
-        /*floor_depth = SHR32(MULT16_16((C*bins<<BITRES),celt_log2(SHL32(MAX16(1,sample_max),13))), DB_SHIFT);*/
-        floor_depth = (opus_int32)SHR32(MULT16_16((C*bins<<BITRES),maxDepth), DB_SHIFT);
-        floor_depth = IMAX(floor_depth, target>>2);
-        target = IMIN(target, floor_depth);
-        /*printf("%f %d\n", maxDepth, floor_depth);*/
-     }
+        base_target += (st->vbr_offset>>lm_diff);
 
-     if ((!st->energy_mask||st->lfe) && (st->constrained_vbr || st->bitrate<64000))
-     {
-        opus_val16 rate_factor;
-#ifdef FIXED_POINT
-        rate_factor = MAX16(0,(st->bitrate-32000));
-#else
-        rate_factor = MAX16(0,(1.f/32768)*(st->bitrate-32000));
-#endif
-        if (st->constrained_vbr)
-           rate_factor = MIN16(rate_factor, QCONST16(0.67f, 15));
-        target = base_target + (opus_int32)MULT16_32_Q15(rate_factor, target-base_target);
-
-     }
-     /* Don't allow more than doubling the rate */
-     target = IMIN(2*base_target, target);
+     target = compute_vbr(mode, &st->analysis, base_target, LM, st->bitrate,
+           st->lastCodedBands, C, st->intensity, st->constrained_vbr,
+           st->stereo_saving, tot_boost, tf_estimate, pitch_change, maxDepth,
+           st->variable_duration, st->lfe, st->energy_mask!=NULL, surround_masking);
 
      /* The current offset is removed from the target and the space used
         so far is added*/