X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Faudio_buffers.cc;h=825c6c2f3219fa8bd6347d7aeddfc97fc005a29b;hb=0486d4d94900c7f2a2cab7885b3f162d1ad8290c;hp=2ab8e187e3a32f9c3566a669990899cb2caf5649;hpb=3828baf56467224f5d44049bf1e7a7ed11f43a05;p=dcpomatic.git

diff --git a/src/lib/audio_buffers.cc b/src/lib/audio_buffers.cc
index 2ab8e187e..825c6c2f3 100644
--- a/src/lib/audio_buffers.cc
+++ b/src/lib/audio_buffers.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2013 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2017 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -134,7 +134,7 @@ AudioBuffers::set_frames (int32_t f)
 	_frames = f;
 }
 
-/** Make all samples on all channels silent */
+/** Make all frames silent */
 void
 AudioBuffers::make_silent ()
 {
@@ -156,6 +156,10 @@ AudioBuffers::make_silent (int c)
 	}
 }
 
+/** Make some frames.
+ *  @param from Start frame.
+ *  @param frames Number of frames to silence.
+ */
 void
 AudioBuffers::make_silent (int32_t from, int32_t frames)
 {
@@ -198,9 +202,8 @@ AudioBuffers::copy_from (AudioBuffers const * from, int32_t frames_to_copy, int3
  *  @param to Offset to move to.
  *  @param frames Number of frames to move.
  */
-
 void
-AudioBuffers::move (int32_t from, int32_t to, int32_t frames)
+AudioBuffers::move (int32_t frames, int32_t from, int32_t to)
 {
 	if (frames == 0) {
 		return;
@@ -221,6 +224,9 @@ AudioBuffers::move (int32_t from, int32_t to, int32_t frames)
 }
 
 /** Add data from from `from', `from_channel' to our channel `to_channel'.
+ *  @param from Buffers to copy data from.
+ *  @param from_channel Channel index to read in \p from.
+ *  @param to_channel Channel index to accumulate into.
  *  @param gain Linear gain to apply to the data before it is added.
  */
 void
@@ -272,16 +278,23 @@ AudioBuffers::ensure_size (int32_t frames)
 	_allocated_frames = frames;
 }
 
+/** Mix some other buffers with these ones.  The AudioBuffers must have the same number of channels.
+ *  @param from Audio buffers to get data from.
+ *  @param frames Number of frames to mix.
+ *  @param read_offset Offset within `from' to read from.
+ *  @param write_offset Offset within this to mix into.
+ */
 void
-AudioBuffers::accumulate_frames (AudioBuffers const * from, int32_t read_offset, int32_t write_offset, int32_t frames)
+AudioBuffers::accumulate_frames (AudioBuffers const * from, int32_t frames, int32_t read_offset, int32_t write_offset)
 {
 	DCPOMATIC_ASSERT (_channels == from->channels ());
 	DCPOMATIC_ASSERT (read_offset >= 0);
 	DCPOMATIC_ASSERT (write_offset >= 0);
 
+	float** from_data = from->data ();
 	for (int i = 0; i < _channels; ++i) {
 		for (int j = 0; j < frames; ++j) {
-			_data[i][j + write_offset] += from->data()[i][j + read_offset];
+			_data[i][j + write_offset] += from_data[i][j + read_offset];
 		}
 	}
 }
@@ -310,6 +323,11 @@ AudioBuffers::channel (int c) const
 	return o;
 }
 
+/** Copy all the samples from a channel on another AudioBuffers to a channel on this one.
+ *  @param from AudioBuffers to copy from.
+ *  @param from_channel Channel index in `from' to copy from.
+ *  @param to_channel Channel index in this to copy into, overwriting what's already there.
+ */
 void
 AudioBuffers::copy_channel_from (AudioBuffers const * from, int from_channel, int to_channel)
 {
@@ -317,6 +335,7 @@ AudioBuffers::copy_channel_from (AudioBuffers const * from, int from_channel, in
 	memcpy (data(to_channel), from->data(from_channel), frames() * sizeof (float));
 }
 
+/** Make a copy of these AudioBuffers */
 shared_ptr<AudioBuffers>
 AudioBuffers::clone () const
 {
@@ -324,3 +343,22 @@ AudioBuffers::clone () const
 	b->copy_from (this, frames (), 0, 0);
 	return b;
 }
+
+/** Extend these buffers with the data from another.  The AudioBuffers must have the same number of channels. */
+void
+AudioBuffers::append (shared_ptr<const AudioBuffers> other)
+{
+	DCPOMATIC_ASSERT (channels() == other->channels());
+	ensure_size (_frames + other->frames());
+	copy_from (other.get(), other->frames(), 0, _frames);
+	_frames += other->frames();
+}
+
+/** Remove some frames from the start of these AudioBuffers */
+void
+AudioBuffers::trim_start (int32_t frames)
+{
+	DCPOMATIC_ASSERT (frames <= _frames);
+	move (_frames - frames, frames, 0);
+	set_frames (_frames - frames);
+}