aboutsummaryrefslogtreecommitdiffstats
path: root/src/pcm/PcmExport.hxx
diff options
context:
space:
mode:
Diffstat (limited to 'src/pcm/PcmExport.hxx')
-rw-r--r--src/pcm/PcmExport.hxx139
1 files changed, 139 insertions, 0 deletions
diff --git a/src/pcm/PcmExport.hxx b/src/pcm/PcmExport.hxx
new file mode 100644
index 000000000..4fb5cc9fc
--- /dev/null
+++ b/src/pcm/PcmExport.hxx
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef PCM_EXPORT_HXX
+#define PCM_EXPORT_HXX
+
+#include "check.h"
+#include "pcm_buffer.h"
+#include "audio_format.h"
+
+struct audio_format;
+
+/**
+ * An object that handles export of PCM samples to some instance
+ * outside of MPD. It has a few more options to tweak the binary
+ * representation which are not supported by the pcm_convert library.
+ */
+struct PcmExport {
+ /**
+ * The buffer is used to convert DSD samples to the
+ * DSD-over-USB format.
+ *
+ * @see #dsd_usb
+ */
+ struct pcm_buffer dsd_buffer;
+
+ /**
+ * The buffer is used to pack samples, removing padding.
+ *
+ * @see #pack24
+ */
+ struct pcm_buffer pack_buffer;
+
+ /**
+ * The buffer is used to reverse the byte order.
+ *
+ * @see #reverse_endian
+ */
+ struct pcm_buffer reverse_buffer;
+
+ /**
+ * The number of channels.
+ */
+ uint8_t channels;
+
+ /**
+ * Convert DSD to DSD-over-USB? Input format must be
+ * SAMPLE_FORMAT_DSD and output format must be
+ * SAMPLE_FORMAT_S24_P32.
+ */
+ bool dsd_usb;
+
+ /**
+ * Convert (padded) 24 bit samples to 32 bit by shifting 8
+ * bits to the left?
+ */
+ bool shift8;
+
+ /**
+ * Pack 24 bit samples?
+ */
+ bool pack24;
+
+ /**
+ * Export the samples in reverse byte order? A non-zero value
+ * means the option is enabled and represents the size of each
+ * sample (2 or bigger).
+ */
+ uint8_t reverse_endian;
+
+ PcmExport() {
+ pcm_buffer_init(&reverse_buffer);
+ pcm_buffer_init(&pack_buffer);
+ pcm_buffer_init(&dsd_buffer);
+ }
+
+ ~PcmExport() {
+ pcm_buffer_deinit(&reverse_buffer);
+ pcm_buffer_deinit(&pack_buffer);
+ pcm_buffer_deinit(&dsd_buffer);
+ }
+
+ /**
+ * Open the #pcm_export_state object.
+ *
+ * There is no "close" method. This function may be called multiple
+ * times to reuse the object, until pcm_export_deinit() is called.
+ *
+ * This function cannot fail.
+ *
+ * @param channels the number of channels; ignored unless dsd_usb is set
+ */
+ void Open(enum sample_format sample_format, unsigned channels,
+ bool dsd_usb, bool shift8, bool pack, bool reverse_endian);
+
+ /**
+ * Calculate the size of one output frame.
+ */
+ gcc_pure
+ size_t GetFrameSize(const struct audio_format &audio_format) const;
+
+ /**
+ * Export a PCM buffer.
+ *
+ * @param state an initialized and open pcm_export_state object
+ * @param src the source PCM buffer
+ * @param src_size the size of #src in bytes
+ * @param dest_size_r returns the number of bytes of the destination buffer
+ * @return the destination buffer (may be a pointer to the source buffer)
+ */
+ const void *Export(const void *src, size_t src_size,
+ size_t &dest_size_r);
+
+ /**
+ * Converts the number of consumed bytes from the pcm_export()
+ * destination buffer to the according number of bytes from the
+ * pcm_export() source buffer.
+ */
+ gcc_pure
+ size_t CalcSourceSize(size_t dest_size) const;
+};
+
+#endif