X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Faudio_buffers.cc;h=e80142b8e518ad2efe66f5f1c1ee4b90f6dcafa6;hb=f98c4cdec82fc2fbdcc4ca19748d09b0ea0556b4;hp=403babaf7f84bd4b0ff0974d67a4fb5471b93234;hpb=50cb31af16240b248700dab1484d7f07656c66df;p=dcpomatic.git

diff --git a/src/lib/audio_buffers.cc b/src/lib/audio_buffers.cc
index 403babaf7..e80142b8e 100644
--- a/src/lib/audio_buffers.cc
+++ b/src/lib/audio_buffers.cc
@@ -19,6 +19,7 @@
 
 #include <cassert>
 #include <cstring>
+#include <cmath>
 #include <stdexcept>
 #include "audio_buffers.h"
 
@@ -30,69 +31,67 @@ using boost::shared_ptr;
  *  @param frames Number of frames to reserve space for.
  */
 AudioBuffers::AudioBuffers (int channels, int frames)
-	: _channels (channels)
-	, _frames (frames)
-	, _allocated_frames (frames)
 {
-	_data = static_cast<float**> (malloc (_channels * sizeof (float *)));
-	if (!_data) {
-		throw bad_alloc ();
-	}
-	
-	for (int i = 0; i < _channels; ++i) {
-		_data[i] = static_cast<float*> (malloc (frames * sizeof (float)));
-		if (!_data[i]) {
-			throw bad_alloc ();
-		}
-	}
+	allocate (channels, frames);
 }
 
 /** Copy constructor.
  *  @param other Other AudioBuffers; data is copied.
  */
 AudioBuffers::AudioBuffers (AudioBuffers const & other)
-	: _channels (other._channels)
-	, _frames (other._frames)
-	, _allocated_frames (other._frames)
 {
-	_data = static_cast<float**> (malloc (_channels * sizeof (float *)));
-	if (!_data) {
-		throw bad_alloc ();
-	}
-	
-	for (int i = 0; i < _channels; ++i) {
-		_data[i] = static_cast<float*> (malloc (_frames * sizeof (float)));
-		if (!_data[i]) {
-			throw bad_alloc ();
-		}
-		memcpy (_data[i], other._data[i], _frames * sizeof (float));
-	}
+	allocate (other._channels, other._frames);
+	copy_from (&other, other._frames, 0, 0);
 }
 
-/* XXX: it's a shame that this is a copy-and-paste of the above;
-   probably fixable with c++0x.
-*/
 AudioBuffers::AudioBuffers (boost::shared_ptr<const AudioBuffers> other)
-	: _channels (other->_channels)
-	, _frames (other->_frames)
-	, _allocated_frames (other->_frames)
 {
+	allocate (other->_channels, other->_frames);
+	copy_from (other.get(), other->_frames, 0, 0);
+}
+
+AudioBuffers &
+AudioBuffers::operator= (AudioBuffers const & other)
+{
+	if (this == &other) {
+		return *this;
+	}
+		
+	deallocate ();
+	allocate (other._channels, other._frames);
+	copy_from (&other, other._frames, 0, 0);
+
+	return *this;
+}
+
+/** AudioBuffers destructor */
+AudioBuffers::~AudioBuffers ()
+{
+	deallocate ();
+}
+
+void
+AudioBuffers::allocate (int channels, int frames)
+{
+	_channels = channels;
+	_frames = frames;
+	_allocated_frames = frames;
+	
 	_data = static_cast<float**> (malloc (_channels * sizeof (float *)));
 	if (!_data) {
 		throw bad_alloc ();
 	}
 	
 	for (int i = 0; i < _channels; ++i) {
-		_data[i] = static_cast<float*> (malloc (_frames * sizeof (float)));
+		_data[i] = static_cast<float*> (malloc (frames * sizeof (float)));
 		if (!_data[i]) {
 			throw bad_alloc ();
 		}
-		memcpy (_data[i], other->_data[i], _frames * sizeof (float));
 	}
 }
 
-/** AudioBuffers destructor */
-AudioBuffers::~AudioBuffers ()
+void
+AudioBuffers::deallocate ()
 {
 	for (int i = 0; i < _channels; ++i) {
 		free (_data[i]);
@@ -112,13 +111,21 @@ AudioBuffers::data (int c) const
 }
 
 /** Set the number of frames that these AudioBuffers will report themselves
- *  as having.
+ *  as having.  If we reduce the number of frames, the `lost' frames will
+ *  be silenced.
  *  @param f Frames; must be less than or equal to the number of allocated frames.
  */
 void
 AudioBuffers::set_frames (int f)
 {
 	assert (f <= _allocated_frames);
+
+	for (int c = 0; c < _channels; ++c) {
+		for (int i = f; i < _frames; ++i) {
+			_data[c][i] = 0;
+		}
+	}
+	
 	_frames = f;
 }
 
@@ -144,6 +151,18 @@ AudioBuffers::make_silent (int c)
 	}
 }
 
+void
+AudioBuffers::make_silent (int from, int frames)
+{
+	assert ((from + frames) <= _allocated_frames);
+
+	for (int c = 0; c < _channels; ++c) {
+		for (int i = from; i < (from + frames); ++i) {
+			_data[c][i] = 0;
+		}
+	}
+}
+
 /** Copy data from another AudioBuffers to this one.  All channels are copied.
  *  @param from AudioBuffers to copy from; must have the same number of channels as this.
  *  @param frames_to_copy Number of frames to copy.
@@ -184,7 +203,7 @@ AudioBuffers::move (int from, int to, int frames)
 	assert (frames > 0);
 	assert (frames <= _frames);
 	assert ((from + frames) <= _frames);
-	assert ((to + frames) <= _frames);
+	assert ((to + frames) <= _allocated_frames);
 	
 	for (int i = 0; i < _channels; ++i) {
 		memmove (_data[i] + to, _data[i] + from, frames * sizeof(float));
@@ -197,6 +216,7 @@ AudioBuffers::accumulate_channel (AudioBuffers const * from, int from_channel, i
 {
 	int const N = frames ();
 	assert (from->frames() == N);
+	assert (to_channel <= _channels);
 
 	float* s = from->data (from_channel);
 	float* d = _data[to_channel];
@@ -241,3 +261,15 @@ AudioBuffers::accumulate_frames (AudioBuffers const * from, int read_offset, int
 	}
 }
 
+/** @param dB gain in dB */
+void
+AudioBuffers::apply_gain (float dB)
+{
+	float const linear = pow (10, dB / 20);
+	
+	for (int i = 0; i < _channels; ++i) {
+		for (int j = 0; j < _frames; ++j) {
+			_data[i][j] *= linear;
+		}
+	}
+}