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authorJosh Blum2011-03-09 11:28:09 -0800
committerJosh Blum2011-03-09 11:28:09 -0800
commit6d1d64ebacc156f4df5401dac427b316dd22265d (patch)
treedac9437f3121c8f56dc1188ce2948c6a9c96ada9 /gr-audio/lib/alsa/audio_alsa_source.h
parent4cba8db90fe1412232a4c1a20d834f6ce606baf0 (diff)
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audio: moved alsa support files into subdirectory
Diffstat (limited to 'gr-audio/lib/alsa/audio_alsa_source.h')
-rw-r--r--gr-audio/lib/alsa/audio_alsa_source.h106
1 files changed, 106 insertions, 0 deletions
diff --git a/gr-audio/lib/alsa/audio_alsa_source.h b/gr-audio/lib/alsa/audio_alsa_source.h
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+++ b/gr-audio/lib/alsa/audio_alsa_source.h
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+/* -*- c++ -*- */
+/*
+ * Copyright 2004-2011 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio 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 3, or (at your option)
+ * any later version.
+ *
+ * GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_AUDIO_ALSA_SOURCE_H
+#define INCLUDED_AUDIO_ALSA_SOURCE_H
+
+// use new ALSA API
+#define ALSA_PCM_NEW_HW_PARAMS_API
+#define ALSA_PCM_NEW_SW_PARAMS_API
+
+#include <gr_audio_source.h>
+#include <string>
+#include <alsa/asoundlib.h>
+#include <stdexcept>
+
+class audio_alsa_source;
+typedef boost::shared_ptr<audio_alsa_source> audio_alsa_source_sptr;
+
+/*!
+ * \brief audio source using ALSA
+ *
+ * The source has between 1 and N input streams of floats, where N is
+ * depends on the hardware characteristics of the selected device.
+ *
+ * Output samples will be in the range [-1,1].
+ */
+class audio_alsa_source : public audio_source {
+ // typedef for pointer to class work method
+ typedef int (audio_alsa_source::*work_t)(int noutput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+
+ unsigned int d_sampling_rate;
+ std::string d_device_name;
+ snd_pcm_t *d_pcm_handle;
+ snd_pcm_hw_params_t *d_hw_params;
+ snd_pcm_sw_params_t *d_sw_params;
+ snd_pcm_format_t d_format;
+ unsigned int d_nperiods;
+ unsigned int d_period_time_us; // microseconds
+ snd_pcm_uframes_t d_period_size; // in frames
+ unsigned int d_buffer_size_bytes; // sizeof of d_buffer
+ char *d_buffer;
+ work_t d_worker; // the work method to use
+ unsigned int d_hw_nchan; // # of configured h/w channels
+ bool d_special_case_stereo_to_mono;
+
+ // random stats
+ int d_noverruns; // count of overruns
+ int d_nsuspends; // count of suspends
+
+ void output_error_msg (const char *msg, int err);
+ void bail (const char *msg, int err) throw (std::runtime_error);
+
+public:
+ audio_alsa_source (int sampling_rate, const std::string device_name,
+ bool ok_to_block);
+
+ ~audio_alsa_source ();
+
+ bool check_topology (int ninputs, int noutputs);
+
+ int work (int noutput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+
+protected:
+ bool read_buffer (void *buffer, unsigned nframes, unsigned sizeof_frame);
+
+ int work_s16 (int noutput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+
+ int work_s16_2x1 (int noutput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+
+ int work_s32 (int noutput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+
+ int work_s32_2x1 (int noutput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+};
+
+#endif /* INCLUDED_AUDIO_ALSA_SOURCE_H */