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authorDiego Biurrun <diego@biurrun.de>2015-03-27 12:40:23 +0100
committerDiego Biurrun <diego@biurrun.de>2015-04-09 16:40:12 +0200
commit8d26c193fb42d08602ac93ece039d4718d029adc (patch)
treeced4ff3f94794ab9ca513dd67cedd4519ffeb591 /libavdevice/alsa_enc.c
parentc201069fac9a76e6604f9d84d76a172434d62200 (diff)
downloadffmpeg-8d26c193fb42d08602ac93ece039d4718d029adc.tar.gz
avdevice: Apply a more consistent file naming scheme
Diffstat (limited to 'libavdevice/alsa_enc.c')
-rw-r--r--libavdevice/alsa_enc.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/libavdevice/alsa_enc.c b/libavdevice/alsa_enc.c
new file mode 100644
index 0000000000..30c1719203
--- /dev/null
+++ b/libavdevice/alsa_enc.c
@@ -0,0 +1,117 @@
+/*
+ * ALSA input and output
+ * Copyright (c) 2007 Luca Abeni ( lucabe72 email it )
+ * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr )
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * ALSA input and output: output
+ * @author Luca Abeni ( lucabe72 email it )
+ * @author Benoit Fouet ( benoit fouet free fr )
+ *
+ * This avdevice encoder allows to play audio to an ALSA (Advanced Linux
+ * Sound Architecture) device.
+ *
+ * The filename parameter is the name of an ALSA PCM device capable of
+ * capture, for example "default" or "plughw:1"; see the ALSA documentation
+ * for naming conventions. The empty string is equivalent to "default".
+ *
+ * The playback period is set to the lower value available for the device,
+ * which gives a low latency suitable for real-time playback.
+ */
+
+#include <alsa/asoundlib.h>
+
+#include "libavutil/internal.h"
+
+#include "libavformat/avformat.h"
+
+#include "alsa.h"
+
+static av_cold int audio_write_header(AVFormatContext *s1)
+{
+ AlsaData *s = s1->priv_data;
+ AVStream *st;
+ unsigned int sample_rate;
+ enum AVCodecID codec_id;
+ int res;
+
+ st = s1->streams[0];
+ sample_rate = st->codec->sample_rate;
+ codec_id = st->codec->codec_id;
+ res = ff_alsa_open(s1, SND_PCM_STREAM_PLAYBACK, &sample_rate,
+ st->codec->channels, &codec_id);
+ if (sample_rate != st->codec->sample_rate) {
+ av_log(s1, AV_LOG_ERROR,
+ "sample rate %d not available, nearest is %d\n",
+ st->codec->sample_rate, sample_rate);
+ goto fail;
+ }
+
+ return res;
+
+fail:
+ snd_pcm_close(s->h);
+ return AVERROR(EIO);
+}
+
+static int audio_write_packet(AVFormatContext *s1, AVPacket *pkt)
+{
+ AlsaData *s = s1->priv_data;
+ int res;
+ int size = pkt->size;
+ uint8_t *buf = pkt->data;
+
+ size /= s->frame_size;
+ if (s->reorder_func) {
+ if (size > s->reorder_buf_size)
+ if (ff_alsa_extend_reorder_buf(s, size))
+ return AVERROR(ENOMEM);
+ s->reorder_func(buf, s->reorder_buf, size);
+ buf = s->reorder_buf;
+ }
+ while ((res = snd_pcm_writei(s->h, buf, size)) < 0) {
+ if (res == -EAGAIN) {
+
+ return AVERROR(EAGAIN);
+ }
+
+ if (ff_alsa_xrun_recover(s1, res) < 0) {
+ av_log(s1, AV_LOG_ERROR, "ALSA write error: %s\n",
+ snd_strerror(res));
+
+ return AVERROR(EIO);
+ }
+ }
+
+ return 0;
+}
+
+AVOutputFormat ff_alsa_muxer = {
+ .name = "alsa",
+ .long_name = NULL_IF_CONFIG_SMALL("ALSA audio output"),
+ .priv_data_size = sizeof(AlsaData),
+ .audio_codec = DEFAULT_CODEC_ID,
+ .video_codec = AV_CODEC_ID_NONE,
+ .write_header = audio_write_header,
+ .write_packet = audio_write_packet,
+ .write_trailer = ff_alsa_close,
+ .flags = AVFMT_NOFILE,
+};