Adds support for delayed decision

Variable duration option renamed to OPUS_SET_EXPERT_FRAME_DURATION,
with new API.
Also moves up the analysis to avoid having to do int->float conversion
on large buffers.

7 files changed, 394 insertions, 121 deletions

diff --git a/include/opus_defines.h b/include/opus_defines.h
index e9434aab..203144a7 100644
--- a/include/opus_defines.h
+++ b/include/opus_defines.h
@@ -149,8 +149,8 @@ extern "C" {
 #define OPUS_SET_LSB_DEPTH_REQUEST           4036
 #define OPUS_GET_LSB_DEPTH_REQUEST           4037
 #define OPUS_GET_LAST_PACKET_DURATION_REQUEST 4039
-#define OPUS_SET_EXPERT_VARIABLE_DURATION_REQUEST 4040
-#define OPUS_GET_EXPERT_VARIABLE_DURATION_REQUEST 4041
+#define OPUS_SET_EXPERT_FRAME_DURATION_REQUEST 4040
+#define OPUS_GET_EXPERT_FRAME_DURATION_REQUEST 4041
 
 /* Don't use 4045, it's already taken by OPUS_GET_GAIN_REQUEST */
 
@@ -186,6 +186,15 @@ extern "C" {
 #define OPUS_BANDWIDTH_SUPERWIDEBAND         1104 /**<12 kHz bandpass @hideinitializer*/
 #define OPUS_BANDWIDTH_FULLBAND              1105 /**<20 kHz bandpass @hideinitializer*/
 
+#define OPUS_FRAMESIZE_ARG                   5000 /**< Select frame size from the argument (default) */
+#define OPUS_FRAMESIZE_2_5_MS                5001 /**< Use 2.5 ms frames */
+#define OPUS_FRAMESIZE_5_MS                  5002 /**< Use 5 ms frames */
+#define OPUS_FRAMESIZE_10_MS                 5003 /**< Use 10 ms frames */
+#define OPUS_FRAMESIZE_20_MS                 5004 /**< Use 20 ms frames */
+#define OPUS_FRAMESIZE_40_MS                 5005 /**< Use 40 ms frames */
+#define OPUS_FRAMESIZE_60_MS                 5006 /**< Use 60 ms frames */
+#define OPUS_FRAMESIZE_VARIABLE              5010 /**< Optimize the frame size dynamically */
+
 /**@}*/
 
 
@@ -541,7 +550,7 @@ extern "C" {
   * <dt>1</dt><dd>Enable variable duration.</dd>
   * </dl>
   * @hideinitializer */
-#define OPUS_SET_EXPERT_VARIABLE_DURATION(x) OPUS_SET_EXPERT_VARIABLE_DURATION_REQUEST, __opus_check_int(x)
+#define OPUS_SET_EXPERT_FRAME_DURATION(x) OPUS_SET_EXPERT_FRAME_DURATION_REQUEST, __opus_check_int(x)
 /** Gets the encoder's configured use of variable duration frames.
   * @see OPUS_SET_EXPERT_VARIABLE_DURATION
   * @param[out] x <tt>opus_int32 *</tt>: Returns one of the following values:
@@ -550,7 +559,7 @@ extern "C" {
   * <dt>1</dt><dd>variable duration enabled.</dd>
   * </dl>
   * @hideinitializer */
-#define OPUS_GET_EXPERT_VARIABLE_DURATION(x) OPUS_GET_EXPERT_VARIABLE_DURATION_REQUEST, __opus_check_int_ptr(x)
+#define OPUS_GET_EXPERT_FRAME_DURATION(x) OPUS_GET_EXPERT_FRAME_DURATION_REQUEST, __opus_check_int_ptr(x)
 
 /**@}*/
 
diff --git a/src/analysis.c b/src/analysis.c
index 6b07890a..54005d3a 100644
--- a/src/analysis.c
+++ b/src/analysis.c
@@ -139,10 +139,81 @@ static inline float fast_atan2f(float y, float x) {
    }
 }
 
-void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info, CELTEncoder *celt_enc, const opus_val16 *x, int len, int C, int lsb_depth)
+void tonality_get_info(TonalityAnalysisState *tonal, AnalysisInfo *info_out, int len)
+{
+#if 1
+   int pos;
+   int curr_lookahead;
+   float psum;
+   int i;
+
+   pos = tonal->read_pos;
+   curr_lookahead = tonal->write_pos-tonal->read_pos;
+   if (curr_lookahead<0)
+      curr_lookahead += DETECT_SIZE;
+
+   if (len > 480 && pos != tonal->write_pos)
+   {
+      pos++;
+      if (pos==DETECT_SIZE)
+         pos=0;
+   }
+   if (pos == tonal->write_pos)
+      pos--;
+   if (pos<0)
+      pos = DETECT_SIZE-1;
+   OPUS_COPY(info_out, &tonal->info[pos], 1);
+   tonal->read_subframe += len/120;
+   while (tonal->read_subframe>=4)
+   {
+      tonal->read_subframe -= 4;
+      tonal->read_pos++;
+   }
+   if (tonal->read_pos>=DETECT_SIZE)
+      tonal->read_pos-=DETECT_SIZE;
+
+   /* Compensate for the delay in the features themselves.
+      FIXME: Need a better estimate the 10 I just made up */
+   curr_lookahead = IMAX(curr_lookahead-10, 0);
+
+   psum=0;
+   for (i=0;i<DETECT_SIZE-curr_lookahead;i++)
+      psum += tonal->pmusic[i];
+   for (;i<DETECT_SIZE;i++)
+      psum += tonal->pspeech[i];
+   /*printf("%f %f\n", psum, info_out->music_prob);*/
+
+   info_out->music_prob = psum;
+#else
+   /* If data not available, return invalid */
+   if (tonal->read_pos==tonal->write_pos)
+   {
+      info_out->valid=0;
+      return;
+   }
+
+   OPUS_COPY(info_out, &tonal->info[tonal->read_pos], 1);
+   tonal->read_subframe += len/480;
+   while (tonal->read_subframe>=4)
+   {
+      tonal->read_subframe -= 4;
+      tonal->read_pos++;
+   }
+   if (tonal->read_pos>=DETECT_SIZE)
+      tonal->read_pos-=DETECT_SIZE;
+   if (tonal->read_pos == tonal->write_pos)
+   {
+      tonal->read_pos = tonal->write_pos-1;
+      if (tonal->read_pos<0)
+         tonal->read_pos=DETECT_SIZE-1;
+      tonal->read_subframe = 3;
+   }
+#endif
+}
+
+void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info_out, const CELTMode *celt_mode, const void *x, int len, int offset, int C, int lsb_depth, downmix_func downmix)
 {
     int i, b;
-    const CELTMode *mode;
     const kiss_fft_state *kfft;
     kiss_fft_cpx in[480], out[480];
     int N = 480, N2=240;
@@ -171,8 +242,7 @@ void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info, CELTEnc
     float maxE = 0;
     float noise_floor;
     int remaining;
-
-    celt_encoder_ctl(celt_enc, CELT_GET_MODE(&mode));
+    AnalysisInfo *info;
 
     tonal->last_transition++;
     alpha = 1.f/IMIN(20, 1+tonal->count);
@@ -181,23 +251,19 @@ void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info, CELTEnc
 
     if (tonal->count<4)
        tonal->music_prob = .5;
-    kfft = mode->mdct.kfft[0];
+    kfft = celt_mode->mdct.kfft[0];
     if (tonal->count==0)
        tonal->mem_fill = 240;
-    if (C==1)
-    {
-       for (i=0;i<IMIN(len, ANALYSIS_BUF_SIZE-tonal->mem_fill);i++)
-          tonal->inmem[i+tonal->mem_fill] = x[i];
-    } else {
-       for (i=0;i<IMIN(len, ANALYSIS_BUF_SIZE-tonal->mem_fill);i++)
-          tonal->inmem[i+tonal->mem_fill] = x[2*i]+x[2*i+1];
-    }
+    downmix(x, &tonal->inmem[tonal->mem_fill], IMIN(len, ANALYSIS_BUF_SIZE-tonal->mem_fill), offset, C);
     if (tonal->mem_fill+len < ANALYSIS_BUF_SIZE)
     {
        tonal->mem_fill += len;
        /* Don't have enough to update the analysis */
        return;
     }
+    info = &tonal->info[tonal->write_pos++];
+    if (tonal->write_pos>=DETECT_SIZE)
+       tonal->write_pos-=DETECT_SIZE;
 
     for (i=0;i<N2;i++)
     {
@@ -209,15 +275,7 @@ void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info, CELTEnc
     }
     OPUS_MOVE(tonal->inmem, tonal->inmem+ANALYSIS_BUF_SIZE-240, 240);
     remaining = len - (ANALYSIS_BUF_SIZE-tonal->mem_fill);
-    if (C==1)
-    {
-       for (i=0;i<remaining;i++)
-          tonal->inmem[240+i] = x[ANALYSIS_BUF_SIZE-tonal->mem_fill+i];
-    } else {
-       for (i=0;i<remaining;i++)
-          tonal->inmem[240+i] = x[2*(ANALYSIS_BUF_SIZE-tonal->mem_fill+i)]
-                              + x[2*(ANALYSIS_BUF_SIZE-tonal->mem_fill+i)+1];
-    }
+    downmix(x, &tonal->inmem[240], remaining, offset+ANALYSIS_BUF_SIZE-tonal->mem_fill, C);
     tonal->mem_fill = 240 + remaining;
     opus_fft(kfft, in, out);
 
@@ -450,13 +508,49 @@ void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info, CELTEnc
        tau = .00005f;
        beta = .1f;
        max_certainty = .01f+1.f/(20.f+.5f*tonal->last_transition);
+       max_certainty = 0;
        p0 = (1-tonal->music_prob)*(1-tau) +    tonal->music_prob *tau;
        p1 =    tonal->music_prob *(1-tau) + (1-tonal->music_prob)*tau;
        p0 *= (float)pow(1-frame_prob, beta);
        p1 *= (float)pow(frame_prob, beta);
        tonal->music_prob = MAX16(max_certainty, MIN16(1-max_certainty, p1/(p0+p1)));
        info->music_prob = tonal->music_prob;
-       /*printf("%f %f\n", frame_prob, info->music_prob);*/
+       info->music_prob = frame_prob;
+
+       float psum=1e-20;
+       float speech0 = (float)pow(1-frame_prob, beta);
+       float music0  = (float)pow(frame_prob, beta);
+       if (tonal->count==1)
+       {
+          tonal->pspeech[0]=.5;
+          tonal->pmusic [0]=.5;
+       }
+       float s0, m0;
+       s0 = tonal->pspeech[0] + tonal->pspeech[1];
+       m0 = tonal->pmusic [0] + tonal->pmusic [1];
+       tonal->pspeech[0] = s0*(1-tau)*speech0;
+       tonal->pmusic [0] = m0*(1-tau)*music0;
+       for (i=1;i<DETECT_SIZE-1;i++)
+       {
+          tonal->pspeech[i] = tonal->pspeech[i+1]*speech0;
+          tonal->pmusic [i] = tonal->pmusic [i+1]*music0;
+       }
+       tonal->pspeech[DETECT_SIZE-1] = m0*tau*speech0;
+       tonal->pmusic [DETECT_SIZE-1] = s0*tau*music0;
+
+       for (i=0;i<DETECT_SIZE;i++)
+          psum += tonal->pspeech[i] + tonal->pmusic[i];
+       psum = 1.f/psum;
+       for (i=0;i<DETECT_SIZE;i++)
+       {
+          tonal->pspeech[i] *= psum;
+          tonal->pmusic [i] *= psum;
+       }
+       psum = tonal->pmusic[0];
+       for (i=1;i<DETECT_SIZE;i++)
+          psum += tonal->pspeech[i];
+
+       /*printf("%f %f %f\n", frame_prob, info->music_prob, psum);*/
     }
     if (tonal->last_music != (tonal->music_prob>.5f))
        tonal->last_transition=0;
@@ -484,4 +578,48 @@ void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info, CELTEnc
     /*printf("%d %d\n", info->bandwidth, info->opus_bandwidth);*/
     info->noisiness = frame_noisiness;
     info->valid = 1;
+    if (info_out!=NULL)
+       OPUS_COPY(info_out, info, 1);
+}
+
+int run_analysis(TonalityAnalysisState *analysis, const CELTMode *celt_mode, const void *pcm,
+                        const void *analysis_pcm, int frame_size, int variable_duration, int C, opus_int32 Fs, int bitrate_bps,
+                        int delay_compensation, int lsb_depth, downmix_func downmix, AnalysisInfo *analysis_info)
+{
+   int offset;
+   int pcm_len;
+
+   /* Avoid overflow/wrap-around of the analysis buffer */
+   frame_size = IMIN((DETECT_SIZE-5)*Fs/100, frame_size);
+
+   pcm_len = frame_size - analysis->analysis_offset;
+   offset = 0;
+   do {
+      tonality_analysis(analysis, NULL, celt_mode, analysis_pcm, IMIN(480, pcm_len), offset, C, lsb_depth, downmix);
+      offset += 480;
+      pcm_len -= 480;
+   } while (pcm_len>0);
+   analysis->analysis_offset = frame_size;
+
+   if (variable_duration == OPUS_FRAMESIZE_VARIABLE && frame_size >= Fs/200)
+   {
+      int LM = 3;
+      LM = optimize_framesize(pcm, frame_size, C, Fs, bitrate_bps,
+            analysis->prev_tonality, analysis->subframe_mem, delay_compensation, downmix);
+      while ((Fs/400<<LM)>frame_size)
+         LM--;
+      frame_size = (Fs/400<<LM);
+   } else {
+      frame_size = frame_size_select(frame_size, variable_duration, Fs);
+   }
+   if (frame_size<0)
+      return -1;
+   analysis->analysis_offset -= frame_size;
+
+   /* Only perform analysis up to 20-ms frames. Longer ones will be split if
+      they're in CELT-only mode. */
+   analysis_info->valid = 0;
+   tonality_get_info(analysis, analysis_info, frame_size);
+
+   return frame_size;
 }
diff --git a/src/analysis.h b/src/analysis.h
index 6f3689da..37a8bf40 100644
--- a/src/analysis.h
+++ b/src/analysis.h
@@ -28,10 +28,16 @@
 #ifndef ANALYSIS_H
 #define ANALYSIS_H
 
+#include "celt.h"
+#include "opus_private.h"
+
 #define NB_FRAMES 8
 #define NB_TBANDS 18
 #define NB_TOT_BANDS 21
 #define ANALYSIS_BUF_SIZE 720 /* 15 ms at 48 kHz */
+
+#define DETECT_SIZE 200
+
 typedef struct {
    float angle[240];
    float d_angle[240];
@@ -55,9 +61,23 @@ typedef struct {
    int last_transition;
    int count;
    int opus_bandwidth;
+   opus_val32   subframe_mem[3];
+   int analysis_offset;
+   float pspeech[DETECT_SIZE];
+   float pmusic[DETECT_SIZE];
+   int write_pos;
+   int read_pos;
+   int read_subframe;
+   AnalysisInfo info[DETECT_SIZE];
 } TonalityAnalysisState;
 
 void tonality_analysis(TonalityAnalysisState *tonal, AnalysisInfo *info,
-     CELTEncoder *celt_enc, const opus_val16 *x, int len, int C, int lsb_depth);
+     const CELTMode *celt_mode, const void *x, int len, int offset, int C, int lsb_depth, downmix_func downmix);
+
+void tonality_get_info(TonalityAnalysisState *tonal, AnalysisInfo *info_out, int len);
+
+int run_analysis(TonalityAnalysisState *analysis, const CELTMode *celt_mode, const void *pcm,
+                        const void *analysis_pcm, int frame_size, int variable_duration, int C, opus_int32 Fs, int bitrate_bps,
+                        int delay_compensation, int lsb_depth, downmix_func downmix, AnalysisInfo *analysis_info);
 
 #endif
diff --git a/src/opus_demo.c b/src/opus_demo.c
index 6538aad6..a0acb0cd 100644
--- a/src/opus_demo.c
+++ b/src/opus_demo.c
@@ -244,7 +244,8 @@ int main(int argc, char *argv[])
     int mode_switch_time = 48000;
     int nb_encoded;
     int remaining=0;
-    int variable_duration=0;
+    int variable_duration=OPUS_FRAMESIZE_ARG;
+    int delayed_decision=0;
 
     if (argc < 5 )
     {
@@ -313,7 +314,7 @@ int main(int argc, char *argv[])
     forcechannels = OPUS_AUTO;
     use_dtx = 0;
     packet_loss_perc = 0;
-    max_frame_size = 960*6;
+    max_frame_size = 2*48000;
     curr_read=0;
 
     while( args < argc - 2 ) {
@@ -383,7 +384,11 @@ int main(int argc, char *argv[])
             args++;
         } else if( strcmp( argv[ args ], "-variable-duration" ) == 0 ) {
             check_encoder_option(decode_only, "-variable-duration");
-            variable_duration = 1;
+            variable_duration = OPUS_FRAMESIZE_VARIABLE;
+            args++;
+        } else if( strcmp( argv[ args ], "-delayed-decision" ) == 0 ) {
+            check_encoder_option(decode_only, "-delayed-decision");
+            delayed_decision = 1;
             args++;
         } else if( strcmp( argv[ args ], "-dtx") == 0 ) {
             check_encoder_option(decode_only, "-dtx");
@@ -510,7 +515,7 @@ int main(int argc, char *argv[])
 
        opus_encoder_ctl(enc, OPUS_GET_LOOKAHEAD(&skip));
        opus_encoder_ctl(enc, OPUS_SET_LSB_DEPTH(16));
-       opus_encoder_ctl(enc, OPUS_SET_EXPERT_VARIABLE_DURATION(variable_duration));
+       opus_encoder_ctl(enc, OPUS_SET_EXPERT_FRAME_DURATION(variable_duration));
     }
     if (!encode_only)
     {
@@ -566,6 +571,26 @@ int main(int argc, char *argv[])
     if ( use_inbandfec ) {
         data[1] = (unsigned char*)calloc(max_payload_bytes,sizeof(char));
     }
+    if(delayed_decision)
+    {
+       if (variable_duration!=OPUS_FRAMESIZE_VARIABLE)
+       {
+          if (frame_size==sampling_rate/400)
+             variable_duration = OPUS_FRAMESIZE_2_5_MS;
+          else if (frame_size==sampling_rate/200)
+             variable_duration = OPUS_FRAMESIZE_5_MS;
+          else if (frame_size==sampling_rate/100)
+             variable_duration = OPUS_FRAMESIZE_10_MS;
+          else if (frame_size==sampling_rate/50)
+             variable_duration = OPUS_FRAMESIZE_20_MS;
+          else if (frame_size==sampling_rate/25)
+             variable_duration = OPUS_FRAMESIZE_40_MS;
+          else
+             variable_duration = OPUS_FRAMESIZE_60_MS;
+          opus_encoder_ctl(enc, OPUS_SET_EXPERT_FRAME_DURATION(variable_duration));
+       }
+       frame_size = 2*48000;
+    }
     while (!stop)
     {
         if (delayed_celt)
diff --git a/src/opus_encoder.c b/src/opus_encoder.c
index 19778a40..3cee88b3 100644
--- a/src/opus_encoder.c
+++ b/src/opus_encoder.c
@@ -89,9 +89,9 @@ struct OpusEncoder {
     int          first;
     opus_val16   delay_buffer[MAX_ENCODER_BUFFER*2];
 #ifndef FIXED_POINT
-    opus_val32   subframe_mem[3];
     TonalityAnalysisState analysis;
-    int                   detected_bandwidth;
+    int          detected_bandwidth;
+    int          analysis_offset;
 #endif
     opus_uint32  rangeFinal;
 };
@@ -215,6 +215,7 @@ int opus_encoder_init(OpusEncoder* st, opus_int32 Fs, int channels, int applicat
     st->voice_ratio = -1;
     st->encoder_buffer = st->Fs/100;
     st->lsb_depth = 24;
+    st->variable_duration = OPUS_FRAMESIZE_ARG;
 
     /* Delay compensation of 4 ms (2.5 ms for SILK's extra look-ahead 
        + 1.5 ms for SILK resamplers and stereo prediction) */
@@ -665,28 +666,28 @@ static int transient_viterbi(const float *E, const float *E_1, int N, int frame_
    return best_state;
 }
 
-void downmix_float(const void *_x, float *sub, int subframe, int i, int C)
+void downmix_float(const void *_x, float *sub, int subframe, int offset, int C)
 {
    const float *x;
    int c, j;
    x = (const float *)_x;
    for (j=0;j<subframe;j++)
-      sub[j] = x[(subframe*i+j)*C];
+      sub[j] = x[(j+offset)*C];
    for (c=1;c<C;c++)
       for (j=0;j<subframe;j++)
-         sub[j] += x[(subframe*i+j)*C+c];
+         sub[j] += x[(j+offset)*C+c];
 }
 
-void downmix_int(const void *_x, float *sub, int subframe, int i, int C)
+void downmix_int(const void *_x, float *sub, int subframe, int offset, int C)
 {
    const opus_int16 *x;
    int c, j;
    x = (const opus_int16 *)_x;
    for (j=0;j<subframe;j++)
-      sub[j] = x[(subframe*i+j)*C];
+      sub[j] = x[(j+offset)*C];
    for (c=1;c<C;c++)
       for (j=0;j<subframe;j++)
-         sub[j] += x[(subframe*i+j)*C+c];
+         sub[j] += x[(j+offset)*C+c];
 }
 
 int optimize_framesize(const opus_val16 *x, int len, int C, opus_int32 Fs,
@@ -732,7 +733,7 @@ int optimize_framesize(const opus_val16 *x, int len, int C, opus_int32 Fs,
       int j;
       tmp=EPSILON;
 
-      downmix(x, sub, subframe, i, C);
+      downmix(x, sub, subframe, i*subframe, C);
       if (i==0)
          memx = sub[0];
       for (j=0;j<subframe;j++)
@@ -759,10 +760,36 @@ int optimize_framesize(const opus_val16 *x, int len, int C, opus_int32 Fs,
    }
    return bestLM;
 }
+
 #endif
 
+opus_int32 frame_size_select(opus_int32 frame_size, int variable_duration, opus_int32 Fs)
+{
+   int new_size;
+   if (frame_size<Fs/400)
+      return -1;
+   if (variable_duration == OPUS_FRAMESIZE_ARG)
+      new_size = frame_size;
+   else if (variable_duration == OPUS_FRAMESIZE_VARIABLE)
+      new_size = Fs/50;
+   else if (variable_duration >= OPUS_FRAMESIZE_2_5_MS && variable_duration <= OPUS_FRAMESIZE_60_MS)
+      new_size = IMAX(3*Fs/50, (Fs/400)<<(variable_duration-OPUS_FRAMESIZE_2_5_MS));
+   else
+      return -1;
+   if (new_size>frame_size)
+      return -1;
+   if (400*new_size!=Fs && 200*new_size!=Fs && 100*new_size!=Fs &&
+            50*new_size!=Fs && 25*new_size!=Fs && 50*new_size!=3*Fs)
+      return -1;
+   return new_size;
+}
+
 opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_size,
-                unsigned char *data, opus_int32 out_data_bytes, int lsb_depth)
+                unsigned char *data, opus_int32 out_data_bytes, int lsb_depth
+#ifndef FIXED_POINT
+                , AnalysisInfo *analysis_info
+#endif
+                )
 {
     void *silk_enc;
     CELTEncoder *celt_enc;
@@ -790,11 +817,6 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_
     opus_val16 HB_gain;
     opus_int32 max_data_bytes; /* Max number of bytes we're allowed to use */
     int total_buffer;
-    int perform_analysis=0;
-    int orig_frame_size;
-#ifndef FIXED_POINT
-    AnalysisInfo analysis_info;
-#endif
     VARDECL(opus_val16, tmp_prefill);
 
     ALLOC_STACK;
@@ -820,38 +842,15 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_
 
     lsb_depth = IMIN(lsb_depth, st->lsb_depth);
 
-    orig_frame_size = IMIN(frame_size,st->Fs/50);
-    if (st->variable_duration)
-    {
-       int LM = 3;
-#ifndef FIXED_POINT
-       LM = optimize_framesize(pcm, frame_size, st->channels, st->Fs, st->bitrate_bps,
-             st->analysis.prev_tonality, st->subframe_mem, delay_compensation, downmix_float);
-#endif
-       while ((st->Fs/400<<LM)>frame_size)
-          LM--;
-       frame_size = (st->Fs/400<<LM);
-    }
+    st->voice_ratio = -1;
+
 #ifndef FIXED_POINT
-    /* Only perform analysis up to 20-ms frames. Longer ones will be split if
-       they're in CELT-only mode. */
-    analysis_info.valid = 0;
-    perform_analysis = st->silk_mode.complexity >= 7 && st->Fs==48000;
-    if (!perform_analysis)
-    {
-       st->voice_ratio = -1;
-       st->detected_bandwidth = 0;
-    } else if (frame_size <= st->Fs/50)
+    st->detected_bandwidth = 0;
+    if (analysis_info->valid)
     {
-       tonality_analysis(&st->analysis, &analysis_info, celt_enc, pcm, IMIN(480, frame_size), st->channels, lsb_depth);
-       if (frame_size > st->Fs/100)
-          tonality_analysis(&st->analysis, &analysis_info, celt_enc, pcm+(st->Fs/100)*st->channels, 480, st->channels, lsb_depth);
-       if (analysis_info.valid)
-       {
-          if (st->signal_type == OPUS_AUTO)
-             st->voice_ratio = (int)floor(.5+100*(1-analysis_info.music_prob));
-          st->detected_bandwidth = analysis_info.opus_bandwidth;
-       }
+       if (st->signal_type == OPUS_AUTO)
+          st->voice_ratio = (int)floor(.5+100*(1-analysis_info->music_prob));
+       st->detected_bandwidth = analysis_info->opus_bandwidth;
     }
 #endif
 
@@ -1161,7 +1160,11 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_
           /* When switching from SILK/Hybrid to CELT, only ask for a switch at the last frame */
           if (to_celt && i==nb_frames-1)
              st->user_forced_mode = MODE_CELT_ONLY;
-          tmp_len = opus_encode_native(st, pcm+i*(st->channels*st->Fs/50), st->Fs/50, tmp_data+i*bytes_per_frame, bytes_per_frame, lsb_depth);
+          tmp_len = opus_encode_native(st, pcm+i*(st->channels*st->Fs/50), st->Fs/50, tmp_data+i*bytes_per_frame, bytes_per_frame, lsb_depth
+#ifndef FIXED_POINT
+                , analysis_info
+#endif
+                );
           if (tmp_len<0)
           {
              RESTORE_STACK;
@@ -1187,16 +1190,6 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_
        RESTORE_STACK;
        return ret;
     }
-#ifndef FIXED_POINT
-    /* Perform analysis for 40-60 ms frames */
-    if (perform_analysis && frame_size > st->Fs/50)
-    {
-       int nb_analysis = frame_size/(st->Fs/100);
-       for (i=0;i<nb_analysis;i++)
-          tonality_analysis(&st->analysis, &analysis_info, celt_enc, pcm+i*(st->Fs/100)*st->channels, 480, st->channels, lsb_depth);
-       st->voice_ratio = (int)floor(.5+100*(1-analysis_info.music_prob));
-    }
-#endif
     curr_bandwidth = st->bandwidth;
 
     /* Chooses the appropriate mode for speech
@@ -1446,11 +1439,11 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_
             {
                 opus_int32 bonus=0;
 #ifndef FIXED_POINT
-                if (st->variable_duration && orig_frame_size != frame_size)
+                if (st->variable_duration==OPUS_FRAMESIZE_VARIABLE && frame_size != st->Fs/50)
                 {
-                   bonus = (40*st->stream_channels+40)*(48000/frame_size-48000/orig_frame_size);
-                   if (analysis_info.valid)
-                      bonus = bonus*(1.f+.5*analysis_info.tonality);
+                   bonus = (40*st->stream_channels+40)*(st->Fs/frame_size-50);
+                   if (analysis_info->valid)
+                      bonus = bonus*(1.f+.5*analysis_info->tonality);
                 }
 #endif
                 celt_encoder_ctl(celt_enc, OPUS_SET_VBR(1));
@@ -1587,8 +1580,7 @@ opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_
         if (ec_tell(&enc) <= 8*nb_compr_bytes)
         {
 #ifndef FIXED_POINT
-           if (perform_analysis)
-              celt_encoder_ctl(celt_enc, CELT_SET_ANALYSIS(&analysis_info));
+           celt_encoder_ctl(celt_enc, CELT_SET_ANALYSIS(analysis_info));
 #endif
            ret = celt_encode_with_ec(celt_enc, pcm_buf, frame_size, NULL, nb_compr_bytes, &enc);
            if (ret < 0)
@@ -1688,6 +1680,7 @@ opus_int32 opus_encode_float(OpusEncoder *st, const float *pcm, int frame_size,
    VARDECL(opus_int16, in);
    ALLOC_STACK;
 
+   frame_size = frame_size_select(frame_size, st->variable_duration, st->Fs);
    if(frame_size<0)
    {
       RESTORE_STACK;
@@ -1707,6 +1700,12 @@ opus_int32 opus_encode_float(OpusEncoder *st, const float *pcm, int frame_size,
 opus_int32 opus_encode(OpusEncoder *st, const opus_int16 *pcm, int frame_size,
                 unsigned char *data, opus_int32 out_data_bytes)
 {
+   frame_size = frame_size_select(frame_size, st->variable_duration, st->Fs);
+   if(frame_size<0)
+   {
+      RESTORE_STACK;
+      return OPUS_BAD_ARG;
+   }
    return opus_encode_native(st, pcm, frame_size, data, out_data_bytes, 16);
 }
 
@@ -1715,21 +1714,74 @@ opus_int32 opus_encode(OpusEncoder *st, const opus_int16 *pcm, int frame_size,
       unsigned char *data, opus_int32 max_data_bytes)
 {
    int i, ret;
+   const CELTMode *celt_mode;
+   int delay_compensation;
+   int lsb_depth;
    VARDECL(float, in);
+   AnalysisInfo analysis_info;
    ALLOC_STACK;
 
+   opus_encoder_ctl(st, CELT_GET_MODE(&celt_mode));
+   if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
+      delay_compensation = 0;
+   else
+      delay_compensation = st->delay_compensation;
+
+   lsb_depth = IMIN(16, st->lsb_depth);
+
+   analysis_info.valid = 0;
+   if (st->silk_mode.complexity >= 7 && st->Fs==48000)
+   {
+      frame_size = run_analysis(&st->analysis, celt_mode, pcm, pcm+st->channels*st->analysis.analysis_offset,
+            frame_size, st->variable_duration, st->channels, st->Fs, st->bitrate_bps, delay_compensation, lsb_depth, downmix_int, &analysis_info);
+   } else {
+      frame_size = frame_size_select(frame_size, st->variable_duration, st->Fs);
+   }
+   if(frame_size<0)
+   {
+      RESTORE_STACK;
+      return OPUS_BAD_ARG;
+   }
+
    ALLOC(in, frame_size*st->channels, float);
 
    for (i=0;i<frame_size*st->channels;i++)
       in[i] = (1.0f/32768)*pcm[i];
-   ret = opus_encode_native(st, in, frame_size, data, max_data_bytes, 16);
+   ret = opus_encode_native(st, in, frame_size, data, max_data_bytes, 16, &analysis_info);
    RESTORE_STACK;
    return ret;
 }
 opus_int32 opus_encode_float(OpusEncoder *st, const float *pcm, int frame_size,
                       unsigned char *data, opus_int32 out_data_bytes)
 {
-   return opus_encode_native(st, pcm, frame_size, data, out_data_bytes, 24);
+   const CELTMode *celt_mode;
+   int delay_compensation;
+   int lsb_depth;
+   AnalysisInfo analysis_info;
+
+   opus_encoder_ctl(st, CELT_GET_MODE(&celt_mode));
+   if (st->application == OPUS_APPLICATION_RESTRICTED_LOWDELAY)
+      delay_compensation = 0;
+   else
+      delay_compensation = st->delay_compensation;
+
+   lsb_depth = IMIN(24, st->lsb_depth);
+
+   analysis_info.valid = 0;
+   if (st->silk_mode.complexity >= 7 && st->Fs==48000)
+   {
+      frame_size = run_analysis(&st->analysis, celt_mode, pcm, pcm+st->channels*st->analysis.analysis_offset,
+            frame_size, st->variable_duration, st->channels, st->Fs, st->bitrate_bps, delay_compensation, lsb_depth, downmix_float, &analysis_info);
+   } else {
+      frame_size = frame_size_select(frame_size, st->variable_duration, st->Fs);
+   }
+   if(frame_size<0)
+   {
+      RESTORE_STACK;
+      return OPUS_BAD_ARG;
+   }
+
+   return opus_encode_native(st, pcm, frame_size, data, out_data_bytes, 24, &analysis_info);
 
 }
 #endif
@@ -1998,15 +2050,13 @@ int opus_encoder_ctl(OpusEncoder *st, int request, ...)
             *value = st->lsb_depth;
         }
         break;
-        case OPUS_SET_EXPERT_VARIABLE_DURATION_REQUEST:
+        case OPUS_SET_EXPERT_FRAME_DURATION_REQUEST:
         {
             opus_int32 value = va_arg(ap, opus_int32);
-            if (value<0 || value>1)
-               goto bad_arg;
             st->variable_duration = value;
         }
         break;
-        case OPUS_GET_EXPERT_VARIABLE_DURATION_REQUEST:
+        case OPUS_GET_EXPERT_FRAME_DURATION_REQUEST:
         {
             opus_int32 *value = va_arg(ap, opus_int32*);
             *value = st->variable_duration;
@@ -2041,6 +2091,15 @@ int opus_encoder_ctl(OpusEncoder *st, int request, ...)
             st->user_forced_mode = value;
         }
         break;
+
+        case CELT_GET_MODE_REQUEST:
+        {
+           const CELTMode ** value = va_arg(ap, const CELTMode**);
+           if (value==0)
+              goto bad_arg;
+           celt_encoder_ctl(celt_enc, CELT_GET_MODE(value));
+        }
+        break;
         default:
             /* fprintf(stderr, "unknown opus_encoder_ctl() request: %d", request);*/
             ret = OPUS_UNIMPLEMENTED;
diff --git a/src/opus_multistream_encoder.c b/src/opus_multistream_encoder.c
index c5fb3669..c6204185 100644
--- a/src/opus_multistream_encoder.c
+++ b/src/opus_multistream_encoder.c
@@ -36,8 +36,10 @@
 #include <stdarg.h>
 #include "float_cast.h"
 #include "os_support.h"
+#include "analysis.h"
 
 struct OpusMSEncoder {
+   TonalityAnalysisState analysis;
    ChannelLayout layout;
    int variable_duration;
    opus_int32 bitrate_bps;
@@ -105,6 +107,7 @@ int opus_multistream_encoder_init(
    st->layout.nb_coupled_streams = coupled_streams;
 
    st->bitrate_bps = OPUS_AUTO;
+   st->variable_duration = OPUS_FRAMESIZE_ARG;
    for (i=0;i<st->layout.nb_channels;i++)
       st->layout.mapping[i] = mapping[i];
    if (!validate_layout(&st->layout) || !validate_encoder_layout(&st->layout))
@@ -187,6 +190,7 @@ static int opus_multistream_encode_native
     int lsb_depth
 #ifndef FIXED_POINT
     , downmix_func downmix
+    , const void *pcm_analysis
 #endif
 )
 {
@@ -202,10 +206,15 @@ static int opus_multistream_encode_native
    int orig_frame_size;
    int coded_channels;
    opus_int32 channel_rate;
+   opus_int32 complexity;
+   AnalysisInfo analysis_info;
+   const CELTMode *celt_mode;
    ALLOC_STACK;
 
    ptr = (char*)st + align(sizeof(OpusMSEncoder));
    opus_encoder_ctl((OpusEncoder*)ptr, OPUS_GET_SAMPLE_RATE(&Fs));
+   opus_encoder_ctl((OpusEncoder*)ptr, OPUS_GET_COMPLEXITY(&complexity));
+   opus_encoder_ctl((OpusEncoder*)ptr, CELT_GET_MODE(&celt_mode));
 
    if (400*frame_size < Fs)
    {
@@ -213,24 +222,24 @@ static int opus_multistream_encode_native
       return OPUS_BAD_ARG;
    }
    orig_frame_size = IMIN(frame_size,Fs/50);
-   if (st->variable_duration)
+#ifndef FIXED_POINT
+   analysis_info.valid = 0;
+   if (complexity >= 7 && Fs==48000)
    {
-      int LM = 3;
-      int channels;
       opus_int32 delay_compensation;
+      int channels;
 
       channels = st->layout.nb_streams + st->layout.nb_coupled_streams;
       opus_encoder_ctl((OpusEncoder*)ptr, OPUS_GET_LOOKAHEAD(&delay_compensation));
       delay_compensation -= Fs/400;
-#ifndef FIXED_POINT
-      LM = optimize_framesize(pcm, frame_size, channels, Fs, st->bitrate_bps,
-            0.f, st->subframe_mem, delay_compensation, downmix);
+
+      frame_size = run_analysis(&st->analysis, celt_mode, pcm, pcm_analysis,
+            frame_size, st->variable_duration, channels, Fs, st->bitrate_bps, delay_compensation, lsb_depth, downmix, &analysis_info);
+   } else
 #endif
-      while ((Fs/400<<LM)>frame_size)
-         LM--;
-      frame_size = (Fs/400<<LM);
+   {
+      frame_size = frame_size_select(frame_size, st->variable_duration, Fs);
    }
-
    /* Validate frame_size before using it to allocate stack space.
       This mirrors the checks in opus_encode[_float](). */
    if (400*frame_size != Fs && 200*frame_size != Fs &&
@@ -262,10 +271,10 @@ static int opus_multistream_encode_native
       channel_rate = st->bitrate_bps/coded_channels;
    }
 #ifndef FIXED_POINT
-   if (st->variable_duration && orig_frame_size != frame_size)
+   if (st->variable_duration==OPUS_FRAMESIZE_VARIABLE && frame_size != Fs/50)
    {
       opus_int32 bonus;
-      bonus = 60*(48000/frame_size-48000/orig_frame_size);
+      bonus = 60*(Fs/frame_size-50);
       channel_rate += bonus;
    }
 #endif
@@ -313,7 +322,11 @@ static int opus_multistream_encode_native
       /* Reserve three bytes for the last stream and four for the others */
       curr_max -= IMAX(0,4*(st->layout.nb_streams-s-1)-1);
       curr_max = IMIN(curr_max,MS_FRAME_TMP);
-      len = opus_encode_native(enc, buf, frame_size, tmp_data, curr_max, lsb_depth);
+      len = opus_encode_native(enc, buf, frame_size, tmp_data, curr_max, lsb_depth
+#ifndef FIXED_POINT
+            , &analysis_info
+#endif
+            );
       if (len<0)
       {
          RESTORE_STACK;
@@ -412,8 +425,9 @@ int opus_multistream_encode_float
     opus_int32 max_data_bytes
 )
 {
+   int channels = st->layout.nb_streams + st->layout.nb_coupled_streams;
    return opus_multistream_encode_native(st, opus_copy_channel_in_float,
-      pcm, frame_size, data, max_data_bytes, 24, downmix_float);
+      pcm, frame_size, data, max_data_bytes, 24, downmix_float, pcm+channels*st->analysis.analysis_offset);
 }
 
 int opus_multistream_encode(
@@ -424,8 +438,9 @@ int opus_multistream_encode(
     opus_int32 max_data_bytes
 )
 {
+   int channels = st->layout.nb_streams + st->layout.nb_coupled_streams;
    return opus_multistream_encode_native(st, opus_copy_channel_in_short,
-      pcm, frame_size, data, max_data_bytes, 16, downmix_int);
+      pcm, frame_size, data, max_data_bytes, 16, downmix_int, pcm+channels*st->analysis.analysis_offset);
 }
 #endif
 
@@ -562,7 +577,7 @@ int opus_multistream_encoder_ctl(OpusMSEncoder *st, int request, ...)
       *value = (OpusEncoder*)ptr;
    }
    break;
-   case OPUS_SET_EXPERT_VARIABLE_DURATION_REQUEST:
+   case OPUS_SET_EXPERT_FRAME_DURATION_REQUEST:
    {
        opus_int32 value = va_arg(ap, opus_int32);
        if (value<0 || value>1)
@@ -570,7 +585,7 @@ int opus_multistream_encoder_ctl(OpusMSEncoder *st, int request, ...)
        st->variable_duration = value;
    }
    break;
-   case OPUS_GET_EXPERT_VARIABLE_DURATION_REQUEST:
+   case OPUS_GET_EXPERT_FRAME_DURATION_REQUEST:
    {
        opus_int32 *value = va_arg(ap, opus_int32*);
        *value = st->variable_duration;
diff --git a/src/opus_private.h b/src/opus_private.h
index 33a982e5..1da5748b 100644
--- a/src/opus_private.h
+++ b/src/opus_private.h
@@ -31,6 +31,7 @@
 
 #include "arch.h"
 #include "opus.h"
+#include "celt.h"
 
 struct OpusRepacketizer {
    unsigned char toc;
@@ -82,17 +83,23 @@ int get_mono_channel(const ChannelLayout *layout, int stream_id, int prev);
 #define OPUS_SET_FORCE_MODE(x) OPUS_SET_FORCE_MODE_REQUEST, __opus_check_int(x)
 
 typedef void (*downmix_func)(const void *, float *, int, int, int);
-void downmix_float(const void *_x, float *sub, int subframe, int i, int C);
-void downmix_int(const void *_x, float *sub, int subframe, int i, int C);
+void downmix_float(const void *_x, float *sub, int subframe, int offset, int C);
+void downmix_int(const void *_x, float *sub, int subframe, int offset, int C);
 
 int optimize_framesize(const opus_val16 *x, int len, int C, opus_int32 Fs,
                 int bitrate, opus_val16 tonality, opus_val32 *mem, int buffering,
-                void (*downmix)(const void *, float *, int, int, int));
+                downmix_func downmix);
 
 int encode_size(int size, unsigned char *data);
 
+opus_int32 frame_size_select(opus_int32 frame_size, int variable_duration, opus_int32 Fs);
+
 opus_int32 opus_encode_native(OpusEncoder *st, const opus_val16 *pcm, int frame_size,
-      unsigned char *data, opus_int32 out_data_bytes, int lsb_depth);
+      unsigned char *data, opus_int32 out_data_bytes, int lsb_depth
+#ifndef FIXED_POINT
+                , AnalysisInfo *analysis_info
+#endif
+      );
 
 int opus_decode_native(OpusDecoder *st, const unsigned char *data, opus_int32 len,
       opus_val16 *pcm, int frame_size, int decode_fec, int self_delimited, int *packet_offset);