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libavdevice/alsa-audio-common.c

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00001 /*
00002  * ALSA input and output
00003  * Copyright (c) 2007 Luca Abeni ( lucabe72 email it )
00004  * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr )
00005  *
00006  * This file is part of Libav.
00007  *
00008  * Libav is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * Libav is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with Libav; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00031 #include <alsa/asoundlib.h>
00032 #include "libavformat/avformat.h"
00033 #include "libavutil/avassert.h"
00034 #include "libavutil/audioconvert.h"
00035 
00036 #include "alsa-audio.h"
00037 
00038 static av_cold snd_pcm_format_t codec_id_to_pcm_format(int codec_id)
00039 {
00040     switch(codec_id) {
00041         case CODEC_ID_PCM_F64LE: return SND_PCM_FORMAT_FLOAT64_LE;
00042         case CODEC_ID_PCM_F64BE: return SND_PCM_FORMAT_FLOAT64_BE;
00043         case CODEC_ID_PCM_F32LE: return SND_PCM_FORMAT_FLOAT_LE;
00044         case CODEC_ID_PCM_F32BE: return SND_PCM_FORMAT_FLOAT_BE;
00045         case CODEC_ID_PCM_S32LE: return SND_PCM_FORMAT_S32_LE;
00046         case CODEC_ID_PCM_S32BE: return SND_PCM_FORMAT_S32_BE;
00047         case CODEC_ID_PCM_U32LE: return SND_PCM_FORMAT_U32_LE;
00048         case CODEC_ID_PCM_U32BE: return SND_PCM_FORMAT_U32_BE;
00049         case CODEC_ID_PCM_S24LE: return SND_PCM_FORMAT_S24_3LE;
00050         case CODEC_ID_PCM_S24BE: return SND_PCM_FORMAT_S24_3BE;
00051         case CODEC_ID_PCM_U24LE: return SND_PCM_FORMAT_U24_3LE;
00052         case CODEC_ID_PCM_U24BE: return SND_PCM_FORMAT_U24_3BE;
00053         case CODEC_ID_PCM_S16LE: return SND_PCM_FORMAT_S16_LE;
00054         case CODEC_ID_PCM_S16BE: return SND_PCM_FORMAT_S16_BE;
00055         case CODEC_ID_PCM_U16LE: return SND_PCM_FORMAT_U16_LE;
00056         case CODEC_ID_PCM_U16BE: return SND_PCM_FORMAT_U16_BE;
00057         case CODEC_ID_PCM_S8:    return SND_PCM_FORMAT_S8;
00058         case CODEC_ID_PCM_U8:    return SND_PCM_FORMAT_U8;
00059         case CODEC_ID_PCM_MULAW: return SND_PCM_FORMAT_MU_LAW;
00060         case CODEC_ID_PCM_ALAW:  return SND_PCM_FORMAT_A_LAW;
00061         default:                 return SND_PCM_FORMAT_UNKNOWN;
00062     }
00063 }
00064 
00065 #define REORDER_OUT_50(NAME, TYPE) \
00066 static void alsa_reorder_ ## NAME ## _out_50(const void *in_v, void *out_v, int n) \
00067 { \
00068     const TYPE *in = in_v; \
00069     TYPE      *out = out_v; \
00070 \
00071     while (n-- > 0) { \
00072         out[0] = in[0]; \
00073         out[1] = in[1]; \
00074         out[2] = in[3]; \
00075         out[3] = in[4]; \
00076         out[4] = in[2]; \
00077         in  += 5; \
00078         out += 5; \
00079     } \
00080 }
00081 
00082 #define REORDER_OUT_51(NAME, TYPE) \
00083 static void alsa_reorder_ ## NAME ## _out_51(const void *in_v, void *out_v, int n) \
00084 { \
00085     const TYPE *in = in_v; \
00086     TYPE      *out = out_v; \
00087 \
00088     while (n-- > 0) { \
00089         out[0] = in[0]; \
00090         out[1] = in[1]; \
00091         out[2] = in[4]; \
00092         out[3] = in[5]; \
00093         out[4] = in[2]; \
00094         out[5] = in[3]; \
00095         in  += 6; \
00096         out += 6; \
00097     } \
00098 }
00099 
00100 #define REORDER_OUT_71(NAME, TYPE) \
00101 static void alsa_reorder_ ## NAME ## _out_71(const void *in_v, void *out_v, int n) \
00102 { \
00103     const TYPE *in = in_v; \
00104     TYPE      *out = out_v; \
00105 \
00106     while (n-- > 0) { \
00107         out[0] = in[0]; \
00108         out[1] = in[1]; \
00109         out[2] = in[4]; \
00110         out[3] = in[5]; \
00111         out[4] = in[2]; \
00112         out[5] = in[3]; \
00113         out[6] = in[6]; \
00114         out[7] = in[7]; \
00115         in  += 8; \
00116         out += 8; \
00117     } \
00118 }
00119 
00120 REORDER_OUT_50(int8, int8_t)
00121 REORDER_OUT_51(int8, int8_t)
00122 REORDER_OUT_71(int8, int8_t)
00123 REORDER_OUT_50(int16, int16_t)
00124 REORDER_OUT_51(int16, int16_t)
00125 REORDER_OUT_71(int16, int16_t)
00126 REORDER_OUT_50(int32, int32_t)
00127 REORDER_OUT_51(int32, int32_t)
00128 REORDER_OUT_71(int32, int32_t)
00129 REORDER_OUT_50(f32, float)
00130 REORDER_OUT_51(f32, float)
00131 REORDER_OUT_71(f32, float)
00132 
00133 #define FORMAT_I8  0
00134 #define FORMAT_I16 1
00135 #define FORMAT_I32 2
00136 #define FORMAT_F32 3
00137 
00138 #define PICK_REORDER(layout)\
00139 switch(format) {\
00140     case FORMAT_I8:  s->reorder_func = alsa_reorder_int8_out_ ##layout;  break;\
00141     case FORMAT_I16: s->reorder_func = alsa_reorder_int16_out_ ##layout; break;\
00142     case FORMAT_I32: s->reorder_func = alsa_reorder_int32_out_ ##layout; break;\
00143     case FORMAT_F32: s->reorder_func = alsa_reorder_f32_out_ ##layout;   break;\
00144 }
00145 
00146 static av_cold int find_reorder_func(AlsaData *s, int codec_id, uint64_t layout, int out)
00147 {
00148     int format;
00149 
00150     /* reordering input is not currently supported */
00151     if (!out)
00152         return AVERROR(ENOSYS);
00153 
00154     /* reordering is not needed for QUAD or 2_2 layout */
00155     if (layout == AV_CH_LAYOUT_QUAD || layout == AV_CH_LAYOUT_2_2)
00156         return 0;
00157 
00158     switch (codec_id) {
00159     case CODEC_ID_PCM_S8:
00160     case CODEC_ID_PCM_U8:
00161     case CODEC_ID_PCM_ALAW:
00162     case CODEC_ID_PCM_MULAW: format = FORMAT_I8;  break;
00163     case CODEC_ID_PCM_S16LE:
00164     case CODEC_ID_PCM_S16BE:
00165     case CODEC_ID_PCM_U16LE:
00166     case CODEC_ID_PCM_U16BE: format = FORMAT_I16; break;
00167     case CODEC_ID_PCM_S32LE:
00168     case CODEC_ID_PCM_S32BE:
00169     case CODEC_ID_PCM_U32LE:
00170     case CODEC_ID_PCM_U32BE: format = FORMAT_I32; break;
00171     case CODEC_ID_PCM_F32LE:
00172     case CODEC_ID_PCM_F32BE: format = FORMAT_F32; break;
00173     default:                 return AVERROR(ENOSYS);
00174     }
00175 
00176     if      (layout == AV_CH_LAYOUT_5POINT0_BACK || layout == AV_CH_LAYOUT_5POINT0)
00177         PICK_REORDER(50)
00178     else if (layout == AV_CH_LAYOUT_5POINT1_BACK || layout == AV_CH_LAYOUT_5POINT1)
00179         PICK_REORDER(51)
00180     else if (layout == AV_CH_LAYOUT_7POINT1)
00181         PICK_REORDER(71)
00182 
00183     return s->reorder_func ? 0 : AVERROR(ENOSYS);
00184 }
00185 
00186 av_cold int ff_alsa_open(AVFormatContext *ctx, snd_pcm_stream_t mode,
00187                          unsigned int *sample_rate,
00188                          int channels, enum CodecID *codec_id)
00189 {
00190     AlsaData *s = ctx->priv_data;
00191     const char *audio_device;
00192     int res, flags = 0;
00193     snd_pcm_format_t format;
00194     snd_pcm_t *h;
00195     snd_pcm_hw_params_t *hw_params;
00196     snd_pcm_uframes_t buffer_size, period_size;
00197     uint64_t layout = ctx->streams[0]->codec->channel_layout;
00198 
00199     if (ctx->filename[0] == 0) audio_device = "default";
00200     else                       audio_device = ctx->filename;
00201 
00202     if (*codec_id == CODEC_ID_NONE)
00203         *codec_id = DEFAULT_CODEC_ID;
00204     format = codec_id_to_pcm_format(*codec_id);
00205     if (format == SND_PCM_FORMAT_UNKNOWN) {
00206         av_log(ctx, AV_LOG_ERROR, "sample format 0x%04x is not supported\n", *codec_id);
00207         return AVERROR(ENOSYS);
00208     }
00209     s->frame_size = av_get_bits_per_sample(*codec_id) / 8 * channels;
00210 
00211     if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
00212         flags = SND_PCM_NONBLOCK;
00213     }
00214     res = snd_pcm_open(&h, audio_device, mode, flags);
00215     if (res < 0) {
00216         av_log(ctx, AV_LOG_ERROR, "cannot open audio device %s (%s)\n",
00217                audio_device, snd_strerror(res));
00218         return AVERROR(EIO);
00219     }
00220 
00221     res = snd_pcm_hw_params_malloc(&hw_params);
00222     if (res < 0) {
00223         av_log(ctx, AV_LOG_ERROR, "cannot allocate hardware parameter structure (%s)\n",
00224                snd_strerror(res));
00225         goto fail1;
00226     }
00227 
00228     res = snd_pcm_hw_params_any(h, hw_params);
00229     if (res < 0) {
00230         av_log(ctx, AV_LOG_ERROR, "cannot initialize hardware parameter structure (%s)\n",
00231                snd_strerror(res));
00232         goto fail;
00233     }
00234 
00235     res = snd_pcm_hw_params_set_access(h, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
00236     if (res < 0) {
00237         av_log(ctx, AV_LOG_ERROR, "cannot set access type (%s)\n",
00238                snd_strerror(res));
00239         goto fail;
00240     }
00241 
00242     res = snd_pcm_hw_params_set_format(h, hw_params, format);
00243     if (res < 0) {
00244         av_log(ctx, AV_LOG_ERROR, "cannot set sample format 0x%04x %d (%s)\n",
00245                *codec_id, format, snd_strerror(res));
00246         goto fail;
00247     }
00248 
00249     res = snd_pcm_hw_params_set_rate_near(h, hw_params, sample_rate, 0);
00250     if (res < 0) {
00251         av_log(ctx, AV_LOG_ERROR, "cannot set sample rate (%s)\n",
00252                snd_strerror(res));
00253         goto fail;
00254     }
00255 
00256     res = snd_pcm_hw_params_set_channels(h, hw_params, channels);
00257     if (res < 0) {
00258         av_log(ctx, AV_LOG_ERROR, "cannot set channel count to %d (%s)\n",
00259                channels, snd_strerror(res));
00260         goto fail;
00261     }
00262 
00263     snd_pcm_hw_params_get_buffer_size_max(hw_params, &buffer_size);
00264     buffer_size = FFMIN(buffer_size, ALSA_BUFFER_SIZE_MAX);
00265     /* TODO: maybe use ctx->max_picture_buffer somehow */
00266     res = snd_pcm_hw_params_set_buffer_size_near(h, hw_params, &buffer_size);
00267     if (res < 0) {
00268         av_log(ctx, AV_LOG_ERROR, "cannot set ALSA buffer size (%s)\n",
00269                snd_strerror(res));
00270         goto fail;
00271     }
00272 
00273     snd_pcm_hw_params_get_period_size_min(hw_params, &period_size, NULL);
00274     if (!period_size)
00275         period_size = buffer_size / 4;
00276     res = snd_pcm_hw_params_set_period_size_near(h, hw_params, &period_size, NULL);
00277     if (res < 0) {
00278         av_log(ctx, AV_LOG_ERROR, "cannot set ALSA period size (%s)\n",
00279                snd_strerror(res));
00280         goto fail;
00281     }
00282     s->period_size = period_size;
00283 
00284     res = snd_pcm_hw_params(h, hw_params);
00285     if (res < 0) {
00286         av_log(ctx, AV_LOG_ERROR, "cannot set parameters (%s)\n",
00287                snd_strerror(res));
00288         goto fail;
00289     }
00290 
00291     snd_pcm_hw_params_free(hw_params);
00292 
00293     if (channels > 2 && layout) {
00294         if (find_reorder_func(s, *codec_id, layout, mode == SND_PCM_STREAM_PLAYBACK) < 0) {
00295             char name[128];
00296             av_get_channel_layout_string(name, sizeof(name), channels, layout);
00297             av_log(ctx, AV_LOG_WARNING, "ALSA channel layout unknown or unimplemented for %s %s.\n",
00298                    name, mode == SND_PCM_STREAM_PLAYBACK ? "playback" : "capture");
00299         }
00300         if (s->reorder_func) {
00301             s->reorder_buf_size = buffer_size;
00302             s->reorder_buf = av_malloc(s->reorder_buf_size * s->frame_size);
00303             if (!s->reorder_buf)
00304                 goto fail1;
00305         }
00306     }
00307 
00308     s->h = h;
00309     return 0;
00310 
00311 fail:
00312     snd_pcm_hw_params_free(hw_params);
00313 fail1:
00314     snd_pcm_close(h);
00315     return AVERROR(EIO);
00316 }
00317 
00318 av_cold int ff_alsa_close(AVFormatContext *s1)
00319 {
00320     AlsaData *s = s1->priv_data;
00321 
00322     av_freep(&s->reorder_buf);
00323     snd_pcm_close(s->h);
00324     return 0;
00325 }
00326 
00327 int ff_alsa_xrun_recover(AVFormatContext *s1, int err)
00328 {
00329     AlsaData *s = s1->priv_data;
00330     snd_pcm_t *handle = s->h;
00331 
00332     av_log(s1, AV_LOG_WARNING, "ALSA buffer xrun.\n");
00333     if (err == -EPIPE) {
00334         err = snd_pcm_prepare(handle);
00335         if (err < 0) {
00336             av_log(s1, AV_LOG_ERROR, "cannot recover from underrun (snd_pcm_prepare failed: %s)\n", snd_strerror(err));
00337 
00338             return AVERROR(EIO);
00339         }
00340     } else if (err == -ESTRPIPE) {
00341         av_log(s1, AV_LOG_ERROR, "-ESTRPIPE... Unsupported!\n");
00342 
00343         return -1;
00344     }
00345     return err;
00346 }
00347 
00348 int ff_alsa_extend_reorder_buf(AlsaData *s, int min_size)
00349 {
00350     int size = s->reorder_buf_size;
00351     void *r;
00352 
00353     av_assert0(size != 0);
00354     while (size < min_size)
00355         size *= 2;
00356     r = av_realloc(s->reorder_buf, size * s->frame_size);
00357     if (!r)
00358         return AVERROR(ENOMEM);
00359     s->reorder_buf = r;
00360     s->reorder_buf_size = size;
00361     return 0;
00362 }
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