Timeline: Read interleaved blocks of samples from libsndfile, rather than processing one channel at a time.

nonlib/dsp.C

@@ -136,6 +136,39 @@ buffer_deinterleave_one_channel ( sample_t * __restrict__ dst, const sample_t *
     }
 }
 
+void
+buffer_interleaved_mix ( sample_t *__restrict__ dst, const sample_t * __restrict__ src, int dst_channel, int src_channel, int dst_channels, int src_channels, nframes_t nframes )
+{
+    sample_t * dst_ = (sample_t*) assume_aligned(dst);
+    const sample_t * src_ = (const sample_t*) assume_aligned(src);
+
+    dst_ += dst_channel;
+    src_ += src_channel;
+
+    while ( nframes-- )
+    {
+        *dst_ += *src_;
+        dst_ += dst_channels;
+        src_ += src_channels;
+    }
+}
+
+void
+buffer_interleaved_copy ( sample_t *__restrict__ dst, const sample_t * __restrict__ src, int dst_channel, int src_channel, int dst_channels, int src_channels, nframes_t nframes )
+{
+    sample_t * dst_ = (sample_t*) assume_aligned(dst);
+    const sample_t * src_ = (const sample_t*) assume_aligned(src);
+
+    dst_ += dst_channel;
+    src_ += src_channel;
+
+    while ( nframes-- )
+    {
+        *dst_ = *src_;
+        dst_ += dst_channels;
+        src_ += src_channels;
+    }
+}
 
 void
 buffer_fill_with_silence ( sample_t *buf, nframes_t nframes )

nonlib/dsp.h

@@ -33,6 +33,8 @@ void buffer_mix_with_gain ( sample_t *dst, const sample_t *src, nframes_t nframe
 void buffer_interleave_one_channel ( sample_t *dst, const sample_t *src, int channel, int channels, nframes_t nframes );
 void buffer_interleave_one_channel_and_mix ( sample_t *dst, const sample_t *src, int channel, int channels, nframes_t nframes );
 void buffer_deinterleave_one_channel ( sample_t *dst, const sample_t *src, int channel, int channels, nframes_t nframes );
+void buffer_interleaved_mix ( sample_t *__restrict__ dst, const sample_t * __restrict__ src, int dst_channel, int src_channel, int dst_channels, int src_channels, nframes_t nframes );
+void buffer_interleaved_copy ( sample_t *__restrict__ dst, const sample_t * __restrict__ src, int dst_channel, int src_channel, int dst_channels, int src_channels, nframes_t nframes );
 void buffer_fill_with_silence ( sample_t *buf, nframes_t nframes );
 bool buffer_is_digital_black ( const sample_t *buf, nframes_t nframes );
 float buffer_get_peak ( const sample_t *buf, nframes_t nframes );

timeline/src/Audio_Region.H

@@ -88,7 +88,9 @@ public:
             }
 
         void apply ( sample_t *buf, fade_dir_e dir, nframes_t start, nframes_t nframes ) const;
-    };
+        void apply_interleaved ( sample_t *buf, fade_dir_e dir, nframes_t start, nframes_t nframes, int channels ) const;
+   
+ };
 
 /*     struct Fade_In : public Fade; */
 /*     struct Fade_Out : public Fade; */
@@ -166,7 +168,7 @@ public:
 
     virtual Fl_Color actual_box_color ( void )  const;
     /* Engine */
-    nframes_t read ( sample_t *buf, nframes_t pos, nframes_t nframes, int channel ) const;
+    nframes_t read ( sample_t *buf, bool buf_is_empty, nframes_t pos, nframes_t nframes, int out_channels ) const;
     nframes_t write ( nframes_t nframes );
     void prepare ( void );
     bool finalize ( nframes_t frame );

timeline/src/Engine/Audio_Region.C

@@ -57,19 +57,46 @@ Audio_Region::Fade::apply ( sample_t *buf, Audio_Region::Fade::fade_dir_e dir, n
             *(buf++) *= gain( fi );
 }
 
-/** read the overlapping part of /channel/ at /pos/ for /nframes/ of
-    this region into /buf/, where /pos/ is in timeline frames */
+void
+Audio_Region::Fade::apply_interleaved ( sample_t *buf, Audio_Region::Fade::fade_dir_e dir, nframes_t start, nframes_t nframes, int channels ) const
+{
+//    printf( "apply fade %s: start=%ld end=%lu\n", dir == Fade::Out ? "out" : "in", start, end );
+    if ( ! nframes )
+        return;
+
+    nframes_t n = nframes;
+
+    const double inc = increment();
+    double fi = start / (double)length;
+
+    if ( dir == Fade::Out )
+    {
+        fi = 1.0f - fi;
+        for ( ; n--; fi -= inc  )
+        {
+            const float g = gain(fi);
+
+            for ( int i = channels; i--; )
+                *(buf++) *= g;
+        }
+    }
+    else
+        for ( ; n--; fi += inc )
+        {
+            const float g = gain(fi);
+
+            for ( int i = channels; i--; )
+                *(buf++) *= g;
+        }
+}
+
+
+/** read the overlapping at /pos/ for /nframes/ of this region into
+    /buf/, where /pos/ is in timeline frames. /buf/ is an interleaved
+    buffer of /channels/ channels */
 /* this runs in the diskstream thread. */
-/* FIXME: it is far more efficient to read all the channels from a
-   multichannel source at once... But how should we handle the case of a
-   mismatch between the number of channels in this region's source and
-   the number of channels on the track/buffer this data is being read
-   for? Would it not be better to simply buffer and deinterlace the
-   frames in the Audio_File class instead, so that sequential requests
-   for different channels at the same position avoid hitting the disk
-   again? */
 nframes_t
-Audio_Region::read ( sample_t *buf, nframes_t pos, nframes_t nframes, int channel ) const
+Audio_Region::read ( sample_t *buf, bool buf_is_empty, nframes_t pos, nframes_t nframes, int channels ) const
 {
     THREAD_ASSERT( Playback );
 
@@ -79,6 +106,20 @@ Audio_Region::read ( sample_t *buf, nframes_t pos, nframes_t nframes, int channe
     if ( pos > r.start + r.length || pos + nframes < r.start )
         return 0;
 
+    sample_t *cbuf = NULL;
+
+    if ( buf_is_empty && channels == _clip->channels() )
+    {
+        /* in this case we don't need a temp buffer */
+        cbuf = buf;
+    }
+    else
+    {
+        /* temporary buffer to hold interleaved samples from the clip */
+        cbuf = buffer_alloc( _clip->channels() * nframes );
+        memset(cbuf, 0, _clip->channels() * sizeof(sample_t) * nframes );
+    }
+
     /* calculate offsets into file and sample buffer */
 
     nframes_t sofs,                                              /* offset into source */
@@ -101,50 +142,56 @@ Audio_Region::read ( sample_t *buf, nframes_t pos, nframes_t nframes, int channe
         sofs = pos - r.start;
     }
 
-    if ( ofs >= nframes )
-        return 0;
 
 //    const nframes_t start = ofs + r.start + sofs;
     const nframes_t start = r.offset + sofs;
     const nframes_t len = cnt;
 
+    /* FIXME: keep the declick defults someplace else */
+    Fade declick;
+
+    declick.length = (float)timeline->sample_rate() * 0.01f;
+    declick.type   = Fade::Sigmoid;
+
+    if ( ofs >= nframes )
+    {
+        cnt = 0;
+        goto done;
+    }
+
     if ( len == 0 )
-        return 0;
+    {
+        cnt = 0;
+        goto done;
+    }
 
     /* now that we know how much and where to read, get on with it */
 
     //    printf( "reading region ofs = %lu, sofs = %lu, %lu-%lu\n", ofs, sofs, start, end  );
 
-    /* FIXME: keep the declick defults someplace else */
-    Fade declick;
-
-    declick.length = 256;
-    declick.type   = Fade::Sigmoid;
 
     if ( _loop )
     {
         nframes_t lofs = sofs % _loop;
         nframes_t lstart = r.offset + lofs;
 
-
+        /* read interleaved channels */
         if ( lofs + len > _loop )
         {
-            /* this buffer covers a loop binary */
+            /* this buffer covers a loop boundary */
 
             /* read the first part */
-            cnt = _clip->read( buf + ofs, channel, lstart, len - ( ( lofs + len ) - _loop ) );
+            cnt = _clip->read( cbuf + ( _clip->channels() * ofs ), -1, lstart, len - ( ( lofs + len ) - _loop ) );
             /* read the second part */
-            cnt += _clip->read( buf + ofs + cnt, channel, lstart + cnt, len - cnt );
-
-            /* TODO: declick/crossfade transition? */
+            cnt += _clip->read( cbuf + ( _clip->channels() * ( ofs + cnt ) ), -1, lstart + cnt, len - cnt );
 
             assert( cnt == len );
         }
         else
-            cnt = _clip->read( buf + ofs, channel, lstart, len );
+            cnt = _clip->read( cbuf + ( channels * ofs ), -1, lstart, len );
 
         /* this buffer is inside declicking proximity to the loop boundary */
-
+        
         if ( lofs + cnt + declick.length > _loop /* buffer ends within declick length of the end of loop */
              &&
              sofs + declick.length < r.length /* not the last loop */
@@ -166,9 +213,9 @@ Audio_Region::read ( sample_t *buf, nframes_t pos, nframes_t nframes, int channe
 
             const nframes_t fl = cnt - declick_onset_offset;
 
-            declick.apply( buf + ofs + declick_onset_offset,
-                           Fade::Out,
-                           declick_offset, fl );
+            declick.apply_interleaved( cbuf + ( _clip->channels() * ( ofs + declick_onset_offset  ) ),
+                                       Fade::Out,
+                                       declick_offset, fl, _clip->channels() );
         }
             
         if ( lofs < declick.length /* buffer begins within declick length of beginning of loop */
@@ -181,38 +228,59 @@ Audio_Region::read ( sample_t *buf, nframes_t pos, nframes_t nframes, int channe
             const nframes_t click_len = lofs + cnt > declick_end ? declick_end - lofs : cnt;
 
             /* this is the beginning of the loop next boundary */
-            declick.apply( buf + ofs, Fade::In, lofs, click_len );
+            declick.apply_interleaved( cbuf + ( _clip->channels() * ofs ), Fade::In, lofs, click_len, _clip->channels() );
         }
     }
     else
-        cnt = _clip->read( buf + ofs, channel, start, len );
+        cnt = _clip->read( cbuf + ( _clip->channels() * ofs ), -1, start, len );
 
     if ( ! cnt )
-        return 0;
+        goto done;
 
     /* apply gain */
 
-    buffer_apply_gain_unaligned( buf + ofs, cnt, _scale );
+    /* just do the whole buffer so we can use the alignment optimized
+     * version when we're in the middle of a region, this will be full
+     * anyway */
+    buffer_apply_gain( cbuf, nframes * _clip->channels(), _scale );
 
     /* perform declicking if necessary */
-
-
     {
         assert( cnt <= nframes );
             
         Fade fade;
 
         fade = declick < _fade_in ? _fade_in : declick;
-
+        
         /* do fade in if necessary */
         if ( sofs < fade.length )
-            fade.apply( buf + ofs, Fade::In, sofs, cnt );
+            fade.apply_interleaved( cbuf + ( _clip->channels() * ofs ), Fade::In, sofs, cnt, _clip->channels() );
 
         fade = declick < _fade_out ? _fade_out : declick;
 
         /* do fade out if necessary */
         if ( start + fade.length > r.offset + r.length )
-            fade.apply( buf, Fade::Out, ( start + fade.length ) - ( r.offset + r.length ), cnt );                
+            fade.apply_interleaved( cbuf, Fade::Out, ( start + fade.length ) - ( r.offset + r.length ), cnt, _clip->channels() );
+    }
+
+    if ( buf != cbuf )
+    {
+        /* now interleave the clip channels into the playback buffer */
+        for ( int i = 0; i < channels && i < _clip->channels(); i++ )
+        {
+            if ( buf_is_empty )
+                buffer_interleaved_copy( buf, cbuf, i, i, channels, _clip->channels(), nframes );
+            else
+                buffer_interleaved_mix( buf, cbuf, i, i, channels, _clip->channels(), nframes );
+            
+        }
+    }
+
+done:
+
+    if ( buf != cbuf )
+    {
+        free( cbuf );
     }
 
     return cnt;

timeline/src/Engine/Audio_Sequence.C

@@ -40,33 +40,24 @@ Audio_Sequence::play ( sample_t *buf, nframes_t frame, nframes_t nframes, int ch
 {
     THREAD_ASSERT( Playback );
 
-    sample_t *cbuf = new sample_t[ nframes ];
-
-    memset( cbuf, 0, nframes * sizeof( sample_t ) );
+    bool buf_is_empty = true;
 
     /* quick and dirty--let the regions figure out coverage for themselves */
     for ( list <Sequence_Widget *>::const_iterator i = _widgets.begin();
           i != _widgets.end(); ++i )
     {
         const Audio_Region *r = (Audio_Region*)(*i);
-
-        for ( int i = channels; i--;  )
-        {
-            int nfr;
-
-            if ( ! ( nfr = r->read( cbuf, frame, nframes, i ) ) )
-                /* error ? */
-                continue;
-
-            if ( channels == 1 )
-                buffer_mix( buf, cbuf, nframes );
-            else
-                buffer_interleave_one_channel_and_mix( buf, cbuf, i, channels, nframes );
-        }
+        
+        int nfr;
+        
+        /* read mixes into buf */
+        if ( ! ( nfr = r->read( buf, buf_is_empty, frame, nframes, channels ) ) )
+            /* error ? */
+            continue;
+
+        buf_is_empty = false;
     }
 
-    delete[] cbuf;
-
     /* FIXME: bogus */
     return nframes;
 }

timeline/src/Engine/Playback_DS.C

@@ -88,7 +88,6 @@ Playback_DS::read_block ( sample_t *buf, nframes_t nframes )
         {
             if ( sequence() )
             {
-                
                 /* FIXME: how does this work if _delay is not a multiple of bufsize? */
                 
                 if ( _frame >= _delay )
@@ -121,7 +120,7 @@ Playback_DS::disk_thread ( void )
     /* buffer to hold the interleaved data returned by the track reader */
     sample_t *buf = buffer_alloc( _nframes * channels() * _disk_io_blocks );
 #ifndef AVOID_UNNECESSARY_COPYING
-    sample_t *cbuf = buffer_alloc( _nframes * _disk_io_blocks );
+    sample_t *cbuf = buffer_alloc( _nframes * channels() * _disk_io_blocks );
 #endif
 
     int blocks_ready = 0;