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alsa-audio-common.c
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1 /*
2  * ALSA input and output
3  * Copyright (c) 2007 Luca Abeni ( lucabe72 email it )
4  * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr )
5  *
6  * This file is part of FFmpeg.
7  *
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.
12  *
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.
17  *
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
21  */
22 
23 /**
24  * @file
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 )
29  */
30 
31 #include <alsa/asoundlib.h>
32 #include "avdevice.h"
33 #include "libavutil/avassert.h"
35 
36 #include "alsa-audio.h"
37 
38 static av_cold snd_pcm_format_t codec_id_to_pcm_format(int codec_id)
39 {
40  switch(codec_id) {
41  case AV_CODEC_ID_PCM_F64LE: return SND_PCM_FORMAT_FLOAT64_LE;
42  case AV_CODEC_ID_PCM_F64BE: return SND_PCM_FORMAT_FLOAT64_BE;
43  case AV_CODEC_ID_PCM_F32LE: return SND_PCM_FORMAT_FLOAT_LE;
44  case AV_CODEC_ID_PCM_F32BE: return SND_PCM_FORMAT_FLOAT_BE;
45  case AV_CODEC_ID_PCM_S32LE: return SND_PCM_FORMAT_S32_LE;
46  case AV_CODEC_ID_PCM_S32BE: return SND_PCM_FORMAT_S32_BE;
47  case AV_CODEC_ID_PCM_U32LE: return SND_PCM_FORMAT_U32_LE;
48  case AV_CODEC_ID_PCM_U32BE: return SND_PCM_FORMAT_U32_BE;
49  case AV_CODEC_ID_PCM_S24LE: return SND_PCM_FORMAT_S24_3LE;
50  case AV_CODEC_ID_PCM_S24BE: return SND_PCM_FORMAT_S24_3BE;
51  case AV_CODEC_ID_PCM_U24LE: return SND_PCM_FORMAT_U24_3LE;
52  case AV_CODEC_ID_PCM_U24BE: return SND_PCM_FORMAT_U24_3BE;
53  case AV_CODEC_ID_PCM_S16LE: return SND_PCM_FORMAT_S16_LE;
54  case AV_CODEC_ID_PCM_S16BE: return SND_PCM_FORMAT_S16_BE;
55  case AV_CODEC_ID_PCM_U16LE: return SND_PCM_FORMAT_U16_LE;
56  case AV_CODEC_ID_PCM_U16BE: return SND_PCM_FORMAT_U16_BE;
57  case AV_CODEC_ID_PCM_S8: return SND_PCM_FORMAT_S8;
58  case AV_CODEC_ID_PCM_U8: return SND_PCM_FORMAT_U8;
59  case AV_CODEC_ID_PCM_MULAW: return SND_PCM_FORMAT_MU_LAW;
60  case AV_CODEC_ID_PCM_ALAW: return SND_PCM_FORMAT_A_LAW;
61  default: return SND_PCM_FORMAT_UNKNOWN;
62  }
63 }
64 
65 #define MAKE_REORDER_FUNC(NAME, TYPE, CHANNELS, LAYOUT, MAP) \
66 static void alsa_reorder_ ## NAME ## _ ## LAYOUT(const void *in_v, \
67  void *out_v, \
68  int n) \
69 { \
70  const TYPE *in = in_v; \
71  TYPE *out = out_v; \
72  \
73  while (n-- > 0) { \
74  MAP \
75  in += CHANNELS; \
76  out += CHANNELS; \
77  } \
78 }
79 
80 #define MAKE_REORDER_FUNCS(CHANNELS, LAYOUT, MAP) \
81  MAKE_REORDER_FUNC(int8, int8_t, CHANNELS, LAYOUT, MAP) \
82  MAKE_REORDER_FUNC(int16, int16_t, CHANNELS, LAYOUT, MAP) \
83  MAKE_REORDER_FUNC(int32, int32_t, CHANNELS, LAYOUT, MAP) \
84  MAKE_REORDER_FUNC(f32, float, CHANNELS, LAYOUT, MAP)
85 
86 MAKE_REORDER_FUNCS(5, out_50, \
87  out[0] = in[0]; \
88  out[1] = in[1]; \
89  out[2] = in[3]; \
90  out[3] = in[4]; \
91  out[4] = in[2]; \
92  );
93 
94 MAKE_REORDER_FUNCS(6, out_51, \
95  out[0] = in[0]; \
96  out[1] = in[1]; \
97  out[2] = in[4]; \
98  out[3] = in[5]; \
99  out[4] = in[2]; \
100  out[5] = in[3]; \
101  );
102 
103 MAKE_REORDER_FUNCS(8, out_71, \
104  out[0] = in[0]; \
105  out[1] = in[1]; \
106  out[2] = in[4]; \
107  out[3] = in[5]; \
108  out[4] = in[2]; \
109  out[5] = in[3]; \
110  out[6] = in[6]; \
111  out[7] = in[7]; \
112  );
113 
114 #define FORMAT_I8 0
115 #define FORMAT_I16 1
116 #define FORMAT_I32 2
117 #define FORMAT_F32 3
118 
119 #define PICK_REORDER(layout)\
120 switch(format) {\
121  case FORMAT_I8: s->reorder_func = alsa_reorder_int8_out_ ##layout; break;\
122  case FORMAT_I16: s->reorder_func = alsa_reorder_int16_out_ ##layout; break;\
123  case FORMAT_I32: s->reorder_func = alsa_reorder_int32_out_ ##layout; break;\
124  case FORMAT_F32: s->reorder_func = alsa_reorder_f32_out_ ##layout; break;\
125 }
126 
127 static av_cold int find_reorder_func(AlsaData *s, int codec_id, uint64_t layout, int out)
128 {
129  int format;
130 
131  /* reordering input is not currently supported */
132  if (!out)
133  return AVERROR(ENOSYS);
134 
135  /* reordering is not needed for QUAD or 2_2 layout */
136  if (layout == AV_CH_LAYOUT_QUAD || layout == AV_CH_LAYOUT_2_2)
137  return 0;
138 
139  switch (codec_id) {
140  case AV_CODEC_ID_PCM_S8:
141  case AV_CODEC_ID_PCM_U8:
143  case AV_CODEC_ID_PCM_MULAW: format = FORMAT_I8; break;
147  case AV_CODEC_ID_PCM_U16BE: format = FORMAT_I16; break;
151  case AV_CODEC_ID_PCM_U32BE: format = FORMAT_I32; break;
153  case AV_CODEC_ID_PCM_F32BE: format = FORMAT_F32; break;
154  default: return AVERROR(ENOSYS);
155  }
156 
157  if (layout == AV_CH_LAYOUT_5POINT0_BACK || layout == AV_CH_LAYOUT_5POINT0)
158  PICK_REORDER(50)
159  else if (layout == AV_CH_LAYOUT_5POINT1_BACK || layout == AV_CH_LAYOUT_5POINT1)
160  PICK_REORDER(51)
161  else if (layout == AV_CH_LAYOUT_7POINT1)
162  PICK_REORDER(71)
163 
164  return s->reorder_func ? 0 : AVERROR(ENOSYS);
165 }
166 
167 av_cold int ff_alsa_open(AVFormatContext *ctx, snd_pcm_stream_t mode,
168  unsigned int *sample_rate,
169  int channels, enum AVCodecID *codec_id)
170 {
171  AlsaData *s = ctx->priv_data;
172  const char *audio_device;
173  int res, flags = 0;
174  snd_pcm_format_t format;
175  snd_pcm_t *h;
176  snd_pcm_hw_params_t *hw_params;
177  snd_pcm_uframes_t buffer_size, period_size;
178  uint64_t layout = ctx->streams[0]->codec->channel_layout;
179 
180  if (ctx->filename[0] == 0) audio_device = "default";
181  else audio_device = ctx->filename;
182 
183  if (*codec_id == AV_CODEC_ID_NONE)
184  *codec_id = DEFAULT_CODEC_ID;
185  format = codec_id_to_pcm_format(*codec_id);
186  if (format == SND_PCM_FORMAT_UNKNOWN) {
187  av_log(ctx, AV_LOG_ERROR, "sample format 0x%04x is not supported\n", *codec_id);
188  return AVERROR(ENOSYS);
189  }
190  s->frame_size = av_get_bits_per_sample(*codec_id) / 8 * channels;
191 
192  if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
193  flags = SND_PCM_NONBLOCK;
194  }
195  res = snd_pcm_open(&h, audio_device, mode, flags);
196  if (res < 0) {
197  av_log(ctx, AV_LOG_ERROR, "cannot open audio device %s (%s)\n",
198  audio_device, snd_strerror(res));
199  return AVERROR(EIO);
200  }
201 
202  res = snd_pcm_hw_params_malloc(&hw_params);
203  if (res < 0) {
204  av_log(ctx, AV_LOG_ERROR, "cannot allocate hardware parameter structure (%s)\n",
205  snd_strerror(res));
206  goto fail1;
207  }
208 
209  res = snd_pcm_hw_params_any(h, hw_params);
210  if (res < 0) {
211  av_log(ctx, AV_LOG_ERROR, "cannot initialize hardware parameter structure (%s)\n",
212  snd_strerror(res));
213  goto fail;
214  }
215 
216  res = snd_pcm_hw_params_set_access(h, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
217  if (res < 0) {
218  av_log(ctx, AV_LOG_ERROR, "cannot set access type (%s)\n",
219  snd_strerror(res));
220  goto fail;
221  }
222 
223  res = snd_pcm_hw_params_set_format(h, hw_params, format);
224  if (res < 0) {
225  av_log(ctx, AV_LOG_ERROR, "cannot set sample format 0x%04x %d (%s)\n",
226  *codec_id, format, snd_strerror(res));
227  goto fail;
228  }
229 
230  res = snd_pcm_hw_params_set_rate_near(h, hw_params, sample_rate, 0);
231  if (res < 0) {
232  av_log(ctx, AV_LOG_ERROR, "cannot set sample rate (%s)\n",
233  snd_strerror(res));
234  goto fail;
235  }
236 
237  res = snd_pcm_hw_params_set_channels(h, hw_params, channels);
238  if (res < 0) {
239  av_log(ctx, AV_LOG_ERROR, "cannot set channel count to %d (%s)\n",
240  channels, snd_strerror(res));
241  goto fail;
242  }
243 
244  snd_pcm_hw_params_get_buffer_size_max(hw_params, &buffer_size);
245  buffer_size = FFMIN(buffer_size, ALSA_BUFFER_SIZE_MAX);
246  /* TODO: maybe use ctx->max_picture_buffer somehow */
247  res = snd_pcm_hw_params_set_buffer_size_near(h, hw_params, &buffer_size);
248  if (res < 0) {
249  av_log(ctx, AV_LOG_ERROR, "cannot set ALSA buffer size (%s)\n",
250  snd_strerror(res));
251  goto fail;
252  }
253 
254  snd_pcm_hw_params_get_period_size_min(hw_params, &period_size, NULL);
255  if (!period_size)
256  period_size = buffer_size / 4;
257  res = snd_pcm_hw_params_set_period_size_near(h, hw_params, &period_size, NULL);
258  if (res < 0) {
259  av_log(ctx, AV_LOG_ERROR, "cannot set ALSA period size (%s)\n",
260  snd_strerror(res));
261  goto fail;
262  }
263  s->period_size = period_size;
264 
265  res = snd_pcm_hw_params(h, hw_params);
266  if (res < 0) {
267  av_log(ctx, AV_LOG_ERROR, "cannot set parameters (%s)\n",
268  snd_strerror(res));
269  goto fail;
270  }
271 
272  snd_pcm_hw_params_free(hw_params);
273 
274  if (channels > 2 && layout) {
275  if (find_reorder_func(s, *codec_id, layout, mode == SND_PCM_STREAM_PLAYBACK) < 0) {
276  char name[128];
277  av_get_channel_layout_string(name, sizeof(name), channels, layout);
278  av_log(ctx, AV_LOG_WARNING, "ALSA channel layout unknown or unimplemented for %s %s.\n",
279  name, mode == SND_PCM_STREAM_PLAYBACK ? "playback" : "capture");
280  }
281  if (s->reorder_func) {
282  s->reorder_buf_size = buffer_size;
284  if (!s->reorder_buf)
285  goto fail1;
286  }
287  }
288 
289  s->h = h;
290  return 0;
291 
292 fail:
293  snd_pcm_hw_params_free(hw_params);
294 fail1:
295  snd_pcm_close(h);
296  return AVERROR(EIO);
297 }
298 
300 {
301  AlsaData *s = s1->priv_data;
302 
303  av_freep(&s->reorder_buf);
304  if (CONFIG_ALSA_INDEV)
306  snd_pcm_close(s->h);
307  return 0;
308 }
309 
311 {
312  AlsaData *s = s1->priv_data;
313  snd_pcm_t *handle = s->h;
314 
315  av_log(s1, AV_LOG_WARNING, "ALSA buffer xrun.\n");
316  if (err == -EPIPE) {
317  err = snd_pcm_prepare(handle);
318  if (err < 0) {
319  av_log(s1, AV_LOG_ERROR, "cannot recover from underrun (snd_pcm_prepare failed: %s)\n", snd_strerror(err));
320 
321  return AVERROR(EIO);
322  }
323  } else if (err == -ESTRPIPE) {
324  av_log(s1, AV_LOG_ERROR, "-ESTRPIPE... Unsupported!\n");
325 
326  return -1;
327  }
328  return err;
329 }
330 
332 {
333  int size = s->reorder_buf_size;
334  void *r;
335 
336  av_assert0(size != 0);
337  while (size < min_size)
338  size *= 2;
339  r = av_realloc(s->reorder_buf, size * s->frame_size);
340  if (!r)
341  return AVERROR(ENOMEM);
342  s->reorder_buf = r;
343  s->reorder_buf_size = size;
344  return 0;
345 }
346 
347 /* ported from alsa-utils/aplay.c */
348 int ff_alsa_get_device_list(AVDeviceInfoList *device_list, snd_pcm_stream_t stream_type)
349 {
350  int ret = 0;
351  void **hints, **n;
352  char *name = NULL, *descr = NULL, *io = NULL, *tmp;
353  AVDeviceInfo *new_device = NULL;
354  const char *filter = stream_type == SND_PCM_STREAM_PLAYBACK ? "Output" : "Input";
355 
356  if (snd_device_name_hint(-1, "pcm", &hints) < 0)
357  return AVERROR_EXTERNAL;
358  n = hints;
359  while (*n && !ret) {
360  name = snd_device_name_get_hint(*n, "NAME");
361  descr = snd_device_name_get_hint(*n, "DESC");
362  io = snd_device_name_get_hint(*n, "IOID");
363  if (!io || !strcmp(io, filter)) {
364  new_device = av_mallocz(sizeof(AVDeviceInfo));
365  if (!new_device) {
366  ret = AVERROR(ENOMEM);
367  goto fail;
368  }
369  new_device->device_name = av_strdup(name);
370  if ((tmp = strrchr(descr, '\n')) && tmp[1])
371  new_device->device_description = av_strdup(&tmp[1]);
372  else
373  new_device->device_description = av_strdup(descr);
374  if (!new_device->device_description || !new_device->device_name) {
375  ret = AVERROR(ENOMEM);
376  goto fail;
377  }
378  if ((ret = av_dynarray_add_nofree(&device_list->devices,
379  &device_list->nb_devices, new_device)) < 0) {
380  goto fail;
381  }
382  if (!strcmp(new_device->device_name, "default"))
383  device_list->default_device = device_list->nb_devices - 1;
384  new_device = NULL;
385  }
386  fail:
387  free(io);
388  free(name);
389  free(descr);
390  n++;
391  }
392  if (new_device) {
393  av_free(new_device->device_description);
394  av_free(new_device->device_name);
395  av_free(new_device);
396  }
397  snd_device_name_free_hint(hints);
398  return ret;
399 }