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      1 /*
      2  *  compress_params.h - codec types and parameters for compressed data
      3  *  streaming interface
      4  *
      5  *  Copyright (C) 2011 Intel Corporation
      6  *  Authors:	Pierre-Louis Bossart <pierre-louis.bossart (at) linux.intel.com>
      7  *              Vinod Koul <vinod.koul (at) linux.intel.com>
      8  *
      9  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     10  *
     11  *  This program is free software; you can redistribute it and/or modify
     12  *  it under the terms of the GNU General Public License as published by
     13  *  the Free Software Foundation; version 2 of the License.
     14  *
     15  *  This program is distributed in the hope that it will be useful, but
     16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
     17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     18  *  General Public License for more details.
     19  *
     20  *  You should have received a copy of the GNU General Public License along
     21  *  with this program; if not, write to the Free Software Foundation, Inc.,
     22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
     23  *
     24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     25  *
     26  * The definitions in this file are derived from the OpenMAX AL version 1.1
     27  * and OpenMAX IL v 1.1.2 header files which contain the copyright notice below.
     28  *
     29  * Copyright (c) 2007-2010 The Khronos Group Inc.
     30  *
     31  * Permission is hereby granted, free of charge, to any person obtaining
     32  * a copy of this software and/or associated documentation files (the
     33  * "Materials "), to deal in the Materials without restriction, including
     34  * without limitation the rights to use, copy, modify, merge, publish,
     35  * distribute, sublicense, and/or sell copies of the Materials, and to
     36  * permit persons to whom the Materials are furnished to do so, subject to
     37  * the following conditions:
     38  *
     39  * The above copyright notice and this permission notice shall be included
     40  * in all copies or substantial portions of the Materials.
     41  *
     42  * THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
     43  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     44  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
     45  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
     46  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
     47  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
     48  * MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
     49  *
     50  */
     51 #ifndef __SND_COMPRESS_PARAMS_H
     52 #define __SND_COMPRESS_PARAMS_H
     53 
     54 /* AUDIO CODECS SUPPORTED */
     55 #define MAX_NUM_CODECS 32
     56 #define MAX_NUM_CODEC_DESCRIPTORS 32
     57 #define MAX_NUM_BITRATES 32
     58 #define MAX_NUM_SAMPLE_RATES 32
     59 
     60 /* compressed TX */
     61 #define MAX_NUM_FRAMES_PER_BUFFER 1
     62 #define COMPRESSED_META_DATA_MODE 0x10
     63 #define META_DATA_LEN_BYTES 36
     64 #define Q6_AC3_DECODER	0x00010BF6
     65 #define Q6_EAC3_DECODER 0x00010C3C
     66 #define Q6_DTS		0x00010D88
     67 #define Q6_DTS_LBR	0x00010DBB
     68 
     69 /* Codecs are listed linearly to allow for extensibility */
     70 #define SND_AUDIOCODEC_PCM                   ((__u32) 0x00000001)
     71 #define SND_AUDIOCODEC_MP3                   ((__u32) 0x00000002)
     72 #define SND_AUDIOCODEC_AMR                   ((__u32) 0x00000003)
     73 #define SND_AUDIOCODEC_AMRWB                 ((__u32) 0x00000004)
     74 #define SND_AUDIOCODEC_AMRWBPLUS             ((__u32) 0x00000005)
     75 #define SND_AUDIOCODEC_AAC                   ((__u32) 0x00000006)
     76 #define SND_AUDIOCODEC_WMA                   ((__u32) 0x00000007)
     77 #define SND_AUDIOCODEC_REAL                  ((__u32) 0x00000008)
     78 #define SND_AUDIOCODEC_VORBIS                ((__u32) 0x00000009)
     79 #define SND_AUDIOCODEC_FLAC                  ((__u32) 0x0000000A)
     80 #define SND_AUDIOCODEC_IEC61937              ((__u32) 0x0000000B)
     81 #define SND_AUDIOCODEC_G723_1                ((__u32) 0x0000000C)
     82 #define SND_AUDIOCODEC_G729                  ((__u32) 0x0000000D)
     83 #define SND_AUDIOCODEC_AC3                   ((__u32) 0x0000000E)
     84 #define SND_AUDIOCODEC_DTS                   ((__u32) 0x0000000F)
     85 #define SND_AUDIOCODEC_AC3_PASS_THROUGH      ((__u32) 0x00000010)
     86 #define SND_AUDIOCODEC_WMA_PRO               ((__u32) 0x00000011)
     87 #define SND_AUDIOCODEC_DTS_PASS_THROUGH      ((__u32) 0x00000012)
     88 #define SND_AUDIOCODEC_DTS_LBR               ((__u32) 0x00000013)
     89 #define SND_AUDIOCODEC_DTS_TRANSCODE_LOOPBACK ((__u32) 0x00000014)
     90 #define SND_AUDIOCODEC_PASS_THROUGH          ((__u32) 0x00000015)
     91 #define SND_AUDIOCODEC_MP2                   ((__u32) 0x00000016)
     92 #define SND_AUDIOCODEC_DTS_LBR_PASS_THROUGH  ((__u32) 0x00000017)
     93 #define SND_AUDIOCODEC_EAC3                  ((__u32) 0x00000018)
     94 #define SND_AUDIOCODEC_MAX  SND_AUDIOCODEC_EAC3
     95 
     96 /*
     97  * Profile and modes are listed with bit masks. This allows for a
     98  * more compact representation of fields that will not evolve
     99  * (in contrast to the list of codecs)
    100  */
    101 
    102 #define SND_AUDIOPROFILE_PCM                 ((__u32) 0x00000001)
    103 
    104 /* MP3 modes are only useful for encoders */
    105 #define SND_AUDIOCHANMODE_MP3_MONO           ((__u32) 0x00000001)
    106 #define SND_AUDIOCHANMODE_MP3_STEREO         ((__u32) 0x00000002)
    107 #define SND_AUDIOCHANMODE_MP3_JOINTSTEREO    ((__u32) 0x00000004)
    108 #define SND_AUDIOCHANMODE_MP3_DUAL           ((__u32) 0x00000008)
    109 
    110 #define SND_AUDIOPROFILE_AMR                 ((__u32) 0x00000001)
    111 
    112 /* AMR modes are only useful for encoders */
    113 #define SND_AUDIOMODE_AMR_DTX_OFF            ((__u32) 0x00000001)
    114 #define SND_AUDIOMODE_AMR_VAD1               ((__u32) 0x00000002)
    115 #define SND_AUDIOMODE_AMR_VAD2               ((__u32) 0x00000004)
    116 
    117 #define SND_AUDIOSTREAMFORMAT_UNDEFINED	     ((__u32) 0x00000000)
    118 #define SND_AUDIOSTREAMFORMAT_CONFORMANCE    ((__u32) 0x00000001)
    119 #define SND_AUDIOSTREAMFORMAT_IF1            ((__u32) 0x00000002)
    120 #define SND_AUDIOSTREAMFORMAT_IF2            ((__u32) 0x00000004)
    121 #define SND_AUDIOSTREAMFORMAT_FSF            ((__u32) 0x00000008)
    122 #define SND_AUDIOSTREAMFORMAT_RTPPAYLOAD     ((__u32) 0x00000010)
    123 #define SND_AUDIOSTREAMFORMAT_ITU            ((__u32) 0x00000020)
    124 
    125 #define SND_AUDIOPROFILE_AMRWB               ((__u32) 0x00000001)
    126 
    127 /* AMRWB modes are only useful for encoders */
    128 #define SND_AUDIOMODE_AMRWB_DTX_OFF          ((__u32) 0x00000001)
    129 #define SND_AUDIOMODE_AMRWB_VAD1             ((__u32) 0x00000002)
    130 #define SND_AUDIOMODE_AMRWB_VAD2             ((__u32) 0x00000004)
    131 
    132 #define SND_AUDIOPROFILE_AMRWBPLUS           ((__u32) 0x00000001)
    133 
    134 #define SND_AUDIOPROFILE_AAC                 ((__u32) 0x00000001)
    135 
    136 /* AAC modes are required for encoders and decoders */
    137 #define SND_AUDIOMODE_AAC_MAIN               ((__u32) 0x00000001)
    138 #define SND_AUDIOMODE_AAC_LC                 ((__u32) 0x00000002)
    139 #define SND_AUDIOMODE_AAC_SSR                ((__u32) 0x00000004)
    140 #define SND_AUDIOMODE_AAC_LTP                ((__u32) 0x00000008)
    141 #define SND_AUDIOMODE_AAC_HE                 ((__u32) 0x00000010)
    142 #define SND_AUDIOMODE_AAC_SCALABLE           ((__u32) 0x00000020)
    143 #define SND_AUDIOMODE_AAC_ERLC               ((__u32) 0x00000040)
    144 #define SND_AUDIOMODE_AAC_LD                 ((__u32) 0x00000080)
    145 #define SND_AUDIOMODE_AAC_HE_PS              ((__u32) 0x00000100)
    146 #define SND_AUDIOMODE_AAC_HE_MPS             ((__u32) 0x00000200)
    147 
    148 /* AAC formats are required for encoders and decoders */
    149 #define SND_AUDIOSTREAMFORMAT_MP2ADTS        ((__u32) 0x00000001)
    150 #define SND_AUDIOSTREAMFORMAT_MP4ADTS        ((__u32) 0x00000002)
    151 #define SND_AUDIOSTREAMFORMAT_MP4LOAS        ((__u32) 0x00000004)
    152 #define SND_AUDIOSTREAMFORMAT_MP4LATM        ((__u32) 0x00000008)
    153 #define SND_AUDIOSTREAMFORMAT_ADIF           ((__u32) 0x00000010)
    154 #define SND_AUDIOSTREAMFORMAT_MP4FF          ((__u32) 0x00000020)
    155 #define SND_AUDIOSTREAMFORMAT_RAW            ((__u32) 0x00000040)
    156 
    157 #define SND_AUDIOPROFILE_WMA7                ((__u32) 0x00000001)
    158 #define SND_AUDIOPROFILE_WMA8                ((__u32) 0x00000002)
    159 #define SND_AUDIOPROFILE_WMA9                ((__u32) 0x00000004)
    160 #define SND_AUDIOPROFILE_WMA10               ((__u32) 0x00000008)
    161 
    162 #define SND_AUDIOMODE_WMA_LEVEL1             ((__u32) 0x00000001)
    163 #define SND_AUDIOMODE_WMA_LEVEL2             ((__u32) 0x00000002)
    164 #define SND_AUDIOMODE_WMA_LEVEL3             ((__u32) 0x00000004)
    165 #define SND_AUDIOMODE_WMA_LEVEL4             ((__u32) 0x00000008)
    166 #define SND_AUDIOMODE_WMAPRO_LEVELM0         ((__u32) 0x00000010)
    167 #define SND_AUDIOMODE_WMAPRO_LEVELM1         ((__u32) 0x00000020)
    168 #define SND_AUDIOMODE_WMAPRO_LEVELM2         ((__u32) 0x00000040)
    169 #define SND_AUDIOMODE_WMAPRO_LEVELM3         ((__u32) 0x00000080)
    170 
    171 #define SND_AUDIOSTREAMFORMAT_WMA_ASF        ((__u32) 0x00000001)
    172 /*
    173  * Some implementations strip the ASF header and only send ASF packets
    174  * to the DSP
    175  */
    176 #define SND_AUDIOSTREAMFORMAT_WMA_NOASF_HDR  ((__u32) 0x00000002)
    177 
    178 #define SND_AUDIOPROFILE_REALAUDIO           ((__u32) 0x00000001)
    179 
    180 #define SND_AUDIOMODE_REALAUDIO_G2           ((__u32) 0x00000001)
    181 #define SND_AUDIOMODE_REALAUDIO_8            ((__u32) 0x00000002)
    182 #define SND_AUDIOMODE_REALAUDIO_10           ((__u32) 0x00000004)
    183 #define SND_AUDIOMODE_REALAUDIO_SURROUND     ((__u32) 0x00000008)
    184 
    185 #define SND_AUDIOPROFILE_VORBIS              ((__u32) 0x00000001)
    186 
    187 #define SND_AUDIOMODE_VORBIS                 ((__u32) 0x00000001)
    188 
    189 #define SND_AUDIOPROFILE_FLAC                ((__u32) 0x00000001)
    190 
    191 /*
    192  * Define quality levels for FLAC encoders, from LEVEL0 (fast)
    193  * to LEVEL8 (best)
    194  */
    195 #define SND_AUDIOMODE_FLAC_LEVEL0            ((__u32) 0x00000001)
    196 #define SND_AUDIOMODE_FLAC_LEVEL1            ((__u32) 0x00000002)
    197 #define SND_AUDIOMODE_FLAC_LEVEL2            ((__u32) 0x00000004)
    198 #define SND_AUDIOMODE_FLAC_LEVEL3            ((__u32) 0x00000008)
    199 #define SND_AUDIOMODE_FLAC_LEVEL4            ((__u32) 0x00000010)
    200 #define SND_AUDIOMODE_FLAC_LEVEL5            ((__u32) 0x00000020)
    201 #define SND_AUDIOMODE_FLAC_LEVEL6            ((__u32) 0x00000040)
    202 #define SND_AUDIOMODE_FLAC_LEVEL7            ((__u32) 0x00000080)
    203 #define SND_AUDIOMODE_FLAC_LEVEL8            ((__u32) 0x00000100)
    204 
    205 #define SND_AUDIOSTREAMFORMAT_FLAC           ((__u32) 0x00000001)
    206 #define SND_AUDIOSTREAMFORMAT_FLAC_OGG       ((__u32) 0x00000002)
    207 
    208 /* IEC61937 payloads without CUVP and preambles */
    209 #define SND_AUDIOPROFILE_IEC61937            ((__u32) 0x00000001)
    210 /* IEC61937 with S/PDIF preambles+CUVP bits in 32-bit containers */
    211 #define SND_AUDIOPROFILE_IEC61937_SPDIF      ((__u32) 0x00000002)
    212 
    213 /*
    214  * IEC modes are mandatory for decoders. Format autodetection
    215  * will only happen on the DSP side with mode 0. The PCM mode should
    216  * not be used, the PCM codec should be used instead.
    217  */
    218 #define SND_AUDIOMODE_IEC_REF_STREAM_HEADER  ((__u32) 0x00000000)
    219 #define SND_AUDIOMODE_IEC_LPCM		     ((__u32) 0x00000001)
    220 #define SND_AUDIOMODE_IEC_AC3		     ((__u32) 0x00000002)
    221 #define SND_AUDIOMODE_IEC_MPEG1		     ((__u32) 0x00000004)
    222 #define SND_AUDIOMODE_IEC_MP3		     ((__u32) 0x00000008)
    223 #define SND_AUDIOMODE_IEC_MPEG2		     ((__u32) 0x00000010)
    224 #define SND_AUDIOMODE_IEC_AACLC		     ((__u32) 0x00000020)
    225 #define SND_AUDIOMODE_IEC_DTS		     ((__u32) 0x00000040)
    226 #define SND_AUDIOMODE_IEC_ATRAC		     ((__u32) 0x00000080)
    227 #define SND_AUDIOMODE_IEC_SACD		     ((__u32) 0x00000100)
    228 #define SND_AUDIOMODE_IEC_EAC3		     ((__u32) 0x00000200)
    229 #define SND_AUDIOMODE_IEC_DTS_HD	     ((__u32) 0x00000400)
    230 #define SND_AUDIOMODE_IEC_MLP		     ((__u32) 0x00000800)
    231 #define SND_AUDIOMODE_IEC_DST		     ((__u32) 0x00001000)
    232 #define SND_AUDIOMODE_IEC_WMAPRO	     ((__u32) 0x00002000)
    233 #define SND_AUDIOMODE_IEC_REF_CXT            ((__u32) 0x00004000)
    234 #define SND_AUDIOMODE_IEC_HE_AAC	     ((__u32) 0x00008000)
    235 #define SND_AUDIOMODE_IEC_HE_AAC2	     ((__u32) 0x00010000)
    236 #define SND_AUDIOMODE_IEC_MPEG_SURROUND	     ((__u32) 0x00020000)
    237 
    238 #define SND_AUDIOPROFILE_G723_1              ((__u32) 0x00000001)
    239 
    240 #define SND_AUDIOMODE_G723_1_ANNEX_A         ((__u32) 0x00000001)
    241 #define SND_AUDIOMODE_G723_1_ANNEX_B         ((__u32) 0x00000002)
    242 #define SND_AUDIOMODE_G723_1_ANNEX_C         ((__u32) 0x00000004)
    243 
    244 #define SND_AUDIOPROFILE_G729                ((__u32) 0x00000001)
    245 
    246 #define SND_AUDIOMODE_G729_ANNEX_A           ((__u32) 0x00000001)
    247 #define SND_AUDIOMODE_G729_ANNEX_B           ((__u32) 0x00000002)
    248 
    249 /* <FIXME: multichannel encoders aren't supported for now. Would need
    250    an additional definition of channel arrangement> */
    251 
    252 /* VBR/CBR definitions */
    253 #define SND_RATECONTROLMODE_CONSTANTBITRATE  ((__u32) 0x00000001)
    254 #define SND_RATECONTROLMODE_VARIABLEBITRATE  ((__u32) 0x00000002)
    255 
    256 /* Encoder options */
    257 
    258 struct snd_enc_wma {
    259 	__u32 super_block_align; /* WMA Type-specific data */
    260 	__u32 bits_per_sample;
    261 	__u32 channelmask;
    262 	__u32 encodeopt;
    263 	__u32 encodeopt1;
    264 	__u32 encodeopt2;
    265 };
    266 
    267 
    268 /**
    269  * struct snd_enc_vorbis
    270  * @quality: Sets encoding quality to n, between -1 (low) and 10 (high).
    271  * In the default mode of operation, the quality level is 3.
    272  * Normal quality range is 0 - 10.
    273  * @managed: Boolean. Set  bitrate  management  mode. This turns off the
    274  * normal VBR encoding, but allows hard or soft bitrate constraints to be
    275  * enforced by the encoder. This mode can be slower, and may also be
    276  * lower quality. It is primarily useful for streaming.
    277  * @max_bit_rate: Enabled only if managed is TRUE
    278  * @min_bit_rate: Enabled only if managed is TRUE
    279  * @downmix: Boolean. Downmix input from stereo to mono (has no effect on
    280  * non-stereo streams). Useful for lower-bitrate encoding.
    281  *
    282  * These options were extracted from the OpenMAX IL spec and Gstreamer vorbisenc
    283  * properties
    284  *
    285  * For best quality users should specify VBR mode and set quality levels.
    286  */
    287 
    288 struct snd_enc_vorbis {
    289 	__s32 quality;
    290 	__u32 managed;
    291 	__u32 max_bit_rate;
    292 	__u32 min_bit_rate;
    293 	__u32 downmix;
    294 };
    295 
    296 
    297 /**
    298  * struct snd_enc_real
    299  * @quant_bits: number of coupling quantization bits in the stream
    300  * @start_region: coupling start region in the stream
    301  * @num_regions: number of regions value
    302  *
    303  * These options were extracted from the OpenMAX IL spec
    304  */
    305 
    306 struct snd_enc_real {
    307 	__u32 quant_bits;
    308 	__u32 start_region;
    309 	__u32 num_regions;
    310 };
    311 
    312 /**
    313  * struct snd_enc_flac
    314  * @num: serial number, valid only for OGG formats
    315  *	needs to be set by application
    316  * @gain: Add replay gain tags
    317  *
    318  * These options were extracted from the FLAC online documentation
    319  * at http://flac.sourceforge.net/documentation_tools_flac.html
    320  *
    321  * To make the API simpler, it is assumed that the user will select quality
    322  * profiles. Additional options that affect encoding quality and speed can
    323  * be added at a later stage if needed.
    324  *
    325  * By default the Subset format is used by encoders.
    326  *
    327  * TAGS such as pictures, etc, cannot be handled by an offloaded encoder and are
    328  * not supported in this API.
    329  */
    330 
    331 struct snd_enc_flac {
    332 	__u32 num;
    333 	__u32 gain;
    334 };
    335 
    336 struct snd_enc_generic {
    337 	__u32 bw;	/* encoder bandwidth */
    338 	__s32 reserved[15];
    339 };
    340 struct snd_dec_dts {
    341 	__u32 modelIdLength;
    342 	__u8 *modelId;
    343 };
    344 struct snd_dec_ddp {
    345 	__u32 params_length;
    346 	__u8 *params;
    347 	__u32 params_id[18];
    348 	__u32 params_value[18];
    349 };
    350 union snd_codec_options {
    351 	struct snd_enc_wma wma;
    352 	struct snd_enc_vorbis vorbis;
    353 	struct snd_enc_real real;
    354 	struct snd_enc_flac flac;
    355 	struct snd_enc_generic generic;
    356 	struct snd_dec_dts dts;
    357 	struct snd_dec_ddp ddp;
    358 };
    359 
    360 /** struct snd_codec_desc - description of codec capabilities
    361  * @max_ch: Maximum number of audio channels
    362  * @sample_rates: Sampling rates in Hz, use values like 48000 for this
    363  * @num_sample_rates: Number of valid values in sample_rates array
    364  * @bit_rate: Indexed array containing supported bit rates
    365  * @num_bitrates: Number of valid values in bit_rate array
    366  * @rate_control: value is specified by SND_RATECONTROLMODE defines.
    367  * @profiles: Supported profiles. See SND_AUDIOPROFILE defines.
    368  * @modes: Supported modes. See SND_AUDIOMODE defines
    369  * @formats: Supported formats. See SND_AUDIOSTREAMFORMAT defines
    370  * @min_buffer: Minimum buffer size handled by codec implementation
    371  * @reserved: reserved for future use
    372  *
    373  * This structure provides a scalar value for profiles, modes and stream
    374  * format fields.
    375  * If an implementation supports multiple combinations, they will be listed as
    376  * codecs with different descriptors, for example there would be 2 descriptors
    377  * for AAC-RAW and AAC-ADTS.
    378  * This entails some redundancy but makes it easier to avoid invalid
    379  * configurations.
    380  *
    381  */
    382 
    383 struct snd_codec_desc {
    384 	__u32 max_ch;
    385 	__u32 sample_rates[MAX_NUM_SAMPLE_RATES];
    386 	__u32 num_sample_rates;
    387 	__u32 bit_rate[MAX_NUM_BITRATES];
    388 	__u32 num_bitrates;
    389 	__u32 rate_control;
    390 	__u32 profiles;
    391 	__u32 modes;
    392 	__u32 formats;
    393 	__u32 min_buffer;
    394 	__u32 reserved[15];
    395 };
    396 
    397 /** struct snd_codec
    398  * @id: Identifies the supported audio encoder/decoder.
    399  *		See SND_AUDIOCODEC macros.
    400  * @ch_in: Number of input audio channels
    401  * @ch_out: Number of output channels. In case of contradiction between
    402  *		this field and the channelMode field, the channelMode field
    403  *		overrides.
    404  * @sample_rate: Audio sample rate of input data in Hz, use values like 48000
    405  *             for this.
    406  * @bit_rate: Bitrate of encoded data. May be ignored by decoders
    407  * @rate_control: Encoding rate control. See SND_RATECONTROLMODE defines.
    408  *               Encoders may rely on profiles for quality levels.
    409  *		 May be ignored by decoders.
    410  * @profile: Mandatory for encoders, can be mandatory for specific
    411  *		decoders as well. See SND_AUDIOPROFILE defines.
    412  * @level: Supported level (Only used by WMA at the moment)
    413  * @ch_mode: Channel mode for encoder. See SND_AUDIOCHANMODE defines
    414  * @format: Format of encoded bistream. Mandatory when defined.
    415  *		See SND_AUDIOSTREAMFORMAT defines.
    416  * @align: Block alignment in bytes of an audio sample.
    417  *		Only required for PCM or IEC formats.
    418  * @options: encoder-specific settings
    419  * @reserved: reserved for future use
    420  */
    421 
    422 struct snd_codec {
    423 	__u32 id;
    424 	__u32 ch_in;
    425 	__u32 ch_out;
    426 	__u32 sample_rate;
    427 	__u32 bit_rate;
    428 	__u32 rate_control;
    429 	__u32 profile;
    430 	__u32 level;
    431 	__u32 ch_mode;
    432 	__u32 format;
    433 	__u32 align;
    434 	__u32 transcode_dts;
    435 	struct snd_dec_dts dts;
    436 	union snd_codec_options options;
    437 	__u32 reserved[3];
    438 };
    439 
    440 #endif
    441