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author | jcorgan | 2006-08-03 04:51:51 +0000 |
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committer | jcorgan | 2006-08-03 04:51:51 +0000 |
commit | 5d69a524f81f234b3fbc41d49ba18d6f6886baba (patch) | |
tree | b71312bf7f1e8d10fef0f3ac6f28784065e73e72 /gr-audio-oss/src/audio_oss_source.cc | |
download | gnuradio-5d69a524f81f234b3fbc41d49ba18d6f6886baba.tar.gz gnuradio-5d69a524f81f234b3fbc41d49ba18d6f6886baba.tar.bz2 gnuradio-5d69a524f81f234b3fbc41d49ba18d6f6886baba.zip |
Houston, we have a trunk.
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3122 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat (limited to 'gr-audio-oss/src/audio_oss_source.cc')
-rw-r--r-- | gr-audio-oss/src/audio_oss_source.cc | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/gr-audio-oss/src/audio_oss_source.cc b/gr-audio-oss/src/audio_oss_source.cc new file mode 100644 index 000000000..6afb08831 --- /dev/null +++ b/gr-audio-oss/src/audio_oss_source.cc @@ -0,0 +1,178 @@ +/* -*- c++ -*- */ +/* + * Copyright 2004 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 2, 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., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <audio_oss_source.h> +#include <gr_io_signature.h> +#include <gr_prefs.h> +#include <sys/soundcard.h> +#include <sys/ioctl.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdio.h> +#include <iostream> +#include <stdexcept> + + +static std::string +default_device_name () +{ + return gr_prefs::singleton()->get_string("audio_oss", "default_input_device", "/dev/dsp"); +} + +audio_oss_source_sptr +audio_oss_make_source (int sampling_rate, const std::string dev, bool ok_to_block) +{ + return audio_oss_source_sptr (new audio_oss_source (sampling_rate, dev, ok_to_block)); +} + + +audio_oss_source::audio_oss_source (int sampling_rate, + const std::string device_name, + bool ok_to_block) + : gr_sync_block ("audio_oss_source", + gr_make_io_signature (0, 0, 0), + gr_make_io_signature (1, 2, sizeof (float))), + d_sampling_rate (sampling_rate), + d_device_name (device_name.empty() ? default_device_name() : device_name), + d_fd (-1), d_buffer (0), d_chunk_size (0) +{ + if ((d_fd = open (d_device_name.c_str (), O_RDONLY)) < 0){ + fprintf (stderr, "audio_oss_source: "); + perror (d_device_name.c_str ()); + throw std::runtime_error ("audio_oss_source"); + } + + double CHUNK_TIME = + std::max(0.001, gr_prefs::singleton()->get_double("audio_oss", "latency", 0.005)); + + d_chunk_size = (int) (d_sampling_rate * CHUNK_TIME); + set_output_multiple (d_chunk_size); + + d_buffer = new short [d_chunk_size * 2]; + + int format = AFMT_S16_NE; + int orig_format = format; + if (ioctl (d_fd, SNDCTL_DSP_SETFMT, &format) < 0){ + std::cerr << "audio_oss_source: " << d_device_name << " ioctl failed\n"; + perror (d_device_name.c_str ()); + throw std::runtime_error ("audio_oss_source"); + } + + if (format != orig_format){ + fprintf (stderr, "audio_oss_source: unable to support format %d\n", orig_format); + fprintf (stderr, " card requested %d instead.\n", format); + } + + // set to stereo no matter what. Some hardware only does stereo + int channels = 2; + if (ioctl (d_fd, SNDCTL_DSP_CHANNELS, &channels) < 0 || channels != 2){ + perror ("audio_oss_source: could not set STEREO mode"); + throw std::runtime_error ("audio_oss_source"); + } + + // set sampling freq + int sf = sampling_rate; + if (ioctl (d_fd, SNDCTL_DSP_SPEED, &sf) < 0){ + std::cerr << "audio_oss_source: " + << d_device_name << ": invalid sampling_rate " + << sampling_rate << "\n"; + sampling_rate = 8000; + if (ioctl (d_fd, SNDCTL_DSP_SPEED, &sf) < 0){ + std::cerr << "audio_oss_source: failed to set sampling_rate to 8000\n"; + throw std::runtime_error ("audio_oss_source"); + } + } +} + +audio_oss_source::~audio_oss_source () +{ + close (d_fd); + delete [] d_buffer; +} + +int +audio_oss_source::work (int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) +{ + float *f0 = (float *) output_items[0]; + float *f1 = (float *) output_items[1]; // will be invalid if this is mono output + + const int shorts_per_item = 2; // L + R + const int bytes_per_item = shorts_per_item * sizeof (short); + + // To minimize latency, never return more than CHUNK_TIME + // worth of samples per call to work. + + noutput_items = std::min (noutput_items, d_chunk_size); + + int base = 0; + int ntogo = noutput_items; + + while (ntogo > 0){ + int nbytes = std::min (ntogo, d_chunk_size) * bytes_per_item; + int result_nbytes = read (d_fd, d_buffer, nbytes); + + if (result_nbytes < 0){ + perror ("audio_oss_source"); + return -1; // say we're done + } + + if ((result_nbytes & (bytes_per_item - 1)) != 0){ + fprintf (stderr, "audio_oss_source: internal error.\n"); + throw std::runtime_error ("internal error"); + } + + int result_nitems = result_nbytes / bytes_per_item; + + // now unpack samples into output streams + + switch (output_items.size ()){ + case 1: // mono output + for (int i = 0; i < result_nitems; i++){ + f0[base+i] = d_buffer[2*i+0] * (1.0 / 32767); + } + break; + + case 2: // stereo output + for (int i = 0; i < result_nitems; i++){ + f0[base+i] = d_buffer[2*i+0] * (1.0 / 32767); + f1[base+i] = d_buffer[2*i+1] * (1.0 / 32767); + } + break; + + default: + assert (0); + } + + ntogo -= result_nitems; + base += result_nitems; + } + + return noutput_items - ntogo; +} |