2 * ALSA input and output
3 * Copyright (c) 2007 Luca Abeni ( lucabe72 email it )
4 * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr )
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * ALSA input and output: common code
26 * @author Luca Abeni ( lucabe72 email it )
27 * @author Benoit Fouet ( benoit fouet free fr )
28 * @author Nicolas George ( nicolas george normalesup org )
31 #include <alsa/asoundlib.h>
33 #include "libavutil/avassert.h"
35 #include "alsa-audio.h"
37 static av_cold snd_pcm_format_t codec_id_to_pcm_format(int codec_id)
40 case CODEC_ID_PCM_F64LE: return SND_PCM_FORMAT_FLOAT64_LE;
41 case CODEC_ID_PCM_F64BE: return SND_PCM_FORMAT_FLOAT64_BE;
42 case CODEC_ID_PCM_F32LE: return SND_PCM_FORMAT_FLOAT_LE;
43 case CODEC_ID_PCM_F32BE: return SND_PCM_FORMAT_FLOAT_BE;
44 case CODEC_ID_PCM_S32LE: return SND_PCM_FORMAT_S32_LE;
45 case CODEC_ID_PCM_S32BE: return SND_PCM_FORMAT_S32_BE;
46 case CODEC_ID_PCM_U32LE: return SND_PCM_FORMAT_U32_LE;
47 case CODEC_ID_PCM_U32BE: return SND_PCM_FORMAT_U32_BE;
48 case CODEC_ID_PCM_S24LE: return SND_PCM_FORMAT_S24_3LE;
49 case CODEC_ID_PCM_S24BE: return SND_PCM_FORMAT_S24_3BE;
50 case CODEC_ID_PCM_U24LE: return SND_PCM_FORMAT_U24_3LE;
51 case CODEC_ID_PCM_U24BE: return SND_PCM_FORMAT_U24_3BE;
52 case CODEC_ID_PCM_S16LE: return SND_PCM_FORMAT_S16_LE;
53 case CODEC_ID_PCM_S16BE: return SND_PCM_FORMAT_S16_BE;
54 case CODEC_ID_PCM_U16LE: return SND_PCM_FORMAT_U16_LE;
55 case CODEC_ID_PCM_U16BE: return SND_PCM_FORMAT_U16_BE;
56 case CODEC_ID_PCM_S8: return SND_PCM_FORMAT_S8;
57 case CODEC_ID_PCM_U8: return SND_PCM_FORMAT_U8;
58 case CODEC_ID_PCM_MULAW: return SND_PCM_FORMAT_MU_LAW;
59 case CODEC_ID_PCM_ALAW: return SND_PCM_FORMAT_A_LAW;
60 default: return SND_PCM_FORMAT_UNKNOWN;
64 #define REORDER_OUT_50(NAME, TYPE) \
65 static void alsa_reorder_ ## NAME ## _out_50(const void *in_v, void *out_v, int n) \
67 const TYPE *in = in_v; \
81 #define REORDER_OUT_51(NAME, TYPE) \
82 static void alsa_reorder_ ## NAME ## _out_51(const void *in_v, void *out_v, int n) \
84 const TYPE *in = in_v; \
99 #define REORDER_OUT_71(NAME, TYPE) \
100 static void alsa_reorder_ ## NAME ## _out_71(const void *in_v, void *out_v, int n) \
102 const TYPE *in = in_v; \
119 REORDER_OUT_50(int8, int8_t)
120 REORDER_OUT_51(int8, int8_t)
121 REORDER_OUT_71(int8, int8_t)
122 REORDER_OUT_50(int16, int16_t)
123 REORDER_OUT_51(int16, int16_t)
124 REORDER_OUT_71(int16, int16_t)
125 REORDER_OUT_50(int32, int32_t)
126 REORDER_OUT_51(int32, int32_t)
127 REORDER_OUT_71(int32, int32_t)
128 REORDER_OUT_50(f32, float)
129 REORDER_OUT_51(f32, float)
130 REORDER_OUT_71(f32, float)
137 #define PICK_REORDER(layout)\
139 case FORMAT_I8: s->reorder_func = alsa_reorder_int8_out_ ##layout; break;\
140 case FORMAT_I16: s->reorder_func = alsa_reorder_int16_out_ ##layout; break;\
141 case FORMAT_I32: s->reorder_func = alsa_reorder_int32_out_ ##layout; break;\
142 case FORMAT_F32: s->reorder_func = alsa_reorder_f32_out_ ##layout; break;\
145 static av_cold int find_reorder_func(AlsaData *s, int codec_id, int64_t layout, int out)
149 /* reordering input is not currently supported */
151 return AVERROR(ENOSYS);
153 /* reordering is not needed for QUAD or 2_2 layout */
154 if (layout == AV_CH_LAYOUT_QUAD || layout == AV_CH_LAYOUT_2_2)
158 case CODEC_ID_PCM_S8:
159 case CODEC_ID_PCM_U8:
160 case CODEC_ID_PCM_ALAW:
161 case CODEC_ID_PCM_MULAW: format = FORMAT_I8; break;
162 case CODEC_ID_PCM_S16LE:
163 case CODEC_ID_PCM_S16BE:
164 case CODEC_ID_PCM_U16LE:
165 case CODEC_ID_PCM_U16BE: format = FORMAT_I16; break;
166 case CODEC_ID_PCM_S32LE:
167 case CODEC_ID_PCM_S32BE:
168 case CODEC_ID_PCM_U32LE:
169 case CODEC_ID_PCM_U32BE: format = FORMAT_I32; break;
170 case CODEC_ID_PCM_F32LE:
171 case CODEC_ID_PCM_F32BE: format = FORMAT_F32; break;
172 default: return AVERROR(ENOSYS);
175 if (layout == AV_CH_LAYOUT_5POINT0_BACK || layout == AV_CH_LAYOUT_5POINT0)
177 else if (layout == AV_CH_LAYOUT_5POINT1_BACK || layout == AV_CH_LAYOUT_5POINT1)
179 else if (layout == AV_CH_LAYOUT_7POINT1)
182 return s->reorder_func ? 0 : AVERROR(ENOSYS);
185 av_cold int ff_alsa_open(AVFormatContext *ctx, snd_pcm_stream_t mode,
186 unsigned int *sample_rate,
187 int channels, enum CodecID *codec_id)
189 AlsaData *s = ctx->priv_data;
190 const char *audio_device;
192 snd_pcm_format_t format;
194 snd_pcm_hw_params_t *hw_params;
195 snd_pcm_uframes_t buffer_size, period_size;
196 int64_t layout = ctx->streams[0]->codec->channel_layout;
198 if (ctx->filename[0] == 0) audio_device = "default";
199 else audio_device = ctx->filename;
201 if (*codec_id == CODEC_ID_NONE)
202 *codec_id = DEFAULT_CODEC_ID;
203 format = codec_id_to_pcm_format(*codec_id);
204 if (format == SND_PCM_FORMAT_UNKNOWN) {
205 av_log(ctx, AV_LOG_ERROR, "sample format 0x%04x is not supported\n", *codec_id);
206 return AVERROR(ENOSYS);
208 s->frame_size = av_get_bits_per_sample(*codec_id) / 8 * channels;
210 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
211 flags = SND_PCM_NONBLOCK;
213 res = snd_pcm_open(&h, audio_device, mode, flags);
215 av_log(ctx, AV_LOG_ERROR, "cannot open audio device %s (%s)\n",
216 audio_device, snd_strerror(res));
220 res = snd_pcm_hw_params_malloc(&hw_params);
222 av_log(ctx, AV_LOG_ERROR, "cannot allocate hardware parameter structure (%s)\n",
227 res = snd_pcm_hw_params_any(h, hw_params);
229 av_log(ctx, AV_LOG_ERROR, "cannot initialize hardware parameter structure (%s)\n",
234 res = snd_pcm_hw_params_set_access(h, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
236 av_log(ctx, AV_LOG_ERROR, "cannot set access type (%s)\n",
241 res = snd_pcm_hw_params_set_format(h, hw_params, format);
243 av_log(ctx, AV_LOG_ERROR, "cannot set sample format 0x%04x %d (%s)\n",
244 *codec_id, format, snd_strerror(res));
248 res = snd_pcm_hw_params_set_rate_near(h, hw_params, sample_rate, 0);
250 av_log(ctx, AV_LOG_ERROR, "cannot set sample rate (%s)\n",
255 res = snd_pcm_hw_params_set_channels(h, hw_params, channels);
257 av_log(ctx, AV_LOG_ERROR, "cannot set channel count to %d (%s)\n",
258 channels, snd_strerror(res));
262 snd_pcm_hw_params_get_buffer_size_max(hw_params, &buffer_size);
263 buffer_size = FFMIN(buffer_size, ALSA_BUFFER_SIZE_MAX);
264 /* TODO: maybe use ctx->max_picture_buffer somehow */
265 res = snd_pcm_hw_params_set_buffer_size_near(h, hw_params, &buffer_size);
267 av_log(ctx, AV_LOG_ERROR, "cannot set ALSA buffer size (%s)\n",
272 snd_pcm_hw_params_get_period_size_min(hw_params, &period_size, NULL);
274 period_size = buffer_size / 4;
275 res = snd_pcm_hw_params_set_period_size_near(h, hw_params, &period_size, NULL);
277 av_log(ctx, AV_LOG_ERROR, "cannot set ALSA period size (%s)\n",
281 s->period_size = period_size;
283 res = snd_pcm_hw_params(h, hw_params);
285 av_log(ctx, AV_LOG_ERROR, "cannot set parameters (%s)\n",
290 snd_pcm_hw_params_free(hw_params);
292 if (channels > 2 && layout) {
293 if (find_reorder_func(s, *codec_id, layout, mode == SND_PCM_STREAM_PLAYBACK) < 0) {
295 av_get_channel_layout_string(name, sizeof(name), channels, layout);
296 av_log(ctx, AV_LOG_WARNING, "ALSA channel layout unknown or unimplemented for %s %s.\n",
297 name, mode == SND_PCM_STREAM_PLAYBACK ? "playback" : "capture");
299 if (s->reorder_func) {
300 s->reorder_buf_size = buffer_size;
301 s->reorder_buf = av_malloc(s->reorder_buf_size * s->frame_size);
311 snd_pcm_hw_params_free(hw_params);
317 av_cold int ff_alsa_close(AVFormatContext *s1)
319 AlsaData *s = s1->priv_data;
321 av_freep(&s->reorder_buf);
322 ff_timefilter_destroy(s->timefilter);
327 int ff_alsa_xrun_recover(AVFormatContext *s1, int err)
329 AlsaData *s = s1->priv_data;
330 snd_pcm_t *handle = s->h;
332 av_log(s1, AV_LOG_WARNING, "ALSA buffer xrun.\n");
334 err = snd_pcm_prepare(handle);
336 av_log(s1, AV_LOG_ERROR, "cannot recover from underrun (snd_pcm_prepare failed: %s)\n", snd_strerror(err));
340 } else if (err == -ESTRPIPE) {
341 av_log(s1, AV_LOG_ERROR, "-ESTRPIPE... Unsupported!\n");
348 int ff_alsa_extend_reorder_buf(AlsaData *s, int min_size)
350 int size = s->reorder_buf_size;
353 av_assert0(size != 0);
354 while (size < min_size)
356 r = av_realloc(s->reorder_buf, size * s->frame_size);
358 return AVERROR(ENOMEM);
360 s->reorder_buf_size = size;