libavcodec/audioconvert.c

   1 /*
   2  * audio conversion
   3  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavcodec/audioconvert.c
  24  * audio conversion
  25  * @author Michael Niedermayer <michaelni@gmx.at>
  26  */
  27
  28 #include "libavutil/avstring.h"
  29 #include "avcodec.h"
  30 #include "audioconvert.h"
  31
  32 typedef struct SampleFmtInfo {
  33     const char *name;
  34     int bits;
  35 } SampleFmtInfo;
  36
  37 /** this table gives more information about formats */
  38 static const SampleFmtInfo sample_fmt_info[SAMPLE_FMT_NB] = {
  39     [SAMPLE_FMT_U8]  = { .name = "u8",  .bits = 8 },
  40     [SAMPLE_FMT_S16] = { .name = "s16", .bits = 16 },
  41     [SAMPLE_FMT_S32] = { .name = "s32", .bits = 32 },
  42     [SAMPLE_FMT_FLT] = { .name = "flt", .bits = 32 },
  43     [SAMPLE_FMT_DBL] = { .name = "dbl", .bits = 64 },
  44 };
  45
  46 const char *avcodec_get_sample_fmt_name(int sample_fmt)
  47 {
  48     if (sample_fmt < 0 || sample_fmt >= SAMPLE_FMT_NB)
  49         return NULL;
  50     return sample_fmt_info[sample_fmt].name;
  51 }
  52
  53 enum SampleFormat avcodec_get_sample_fmt(const char* name)
  54 {
  55     int i;
  56
  57     for (i=0; i < SAMPLE_FMT_NB; i++)
  58         if (!strcmp(sample_fmt_info[i].name, name))
  59             return i;
  60     return SAMPLE_FMT_NONE;
  61 }
  62
  63 void avcodec_sample_fmt_string (char *buf, int buf_size, int sample_fmt)
  64 {
  65     /* print header */
  66     if (sample_fmt < 0)
  67         snprintf (buf, buf_size, "name  " " depth");
  68     else if (sample_fmt < SAMPLE_FMT_NB) {
  69         SampleFmtInfo info= sample_fmt_info[sample_fmt];
  70         snprintf (buf, buf_size, "%-6s" "   %2d ", info.name, info.bits);
  71     }
  72 }
  73
  74 static const char* const channel_names[]={
  75     "FL", "FR", "FC", "LFE", "BL",  "BR",  "FLC", "FRC",
  76     "BC", "SL", "SR", "TC",  "TFL", "TFC", "TFR", "TBL",
  77     "TBC", "TBR",
  78     [29] = "DL",
  79     [30] = "DR",
  80 };
  81
  82 const char *get_channel_name(int channel_id)
  83 {
  84     if (channel_id<0 || channel_id>=FF_ARRAY_ELEMS(channel_names))
  85         return NULL;
  86     return channel_names[channel_id];
  87 }
  88
  89 int64_t avcodec_guess_channel_layout(int nb_channels, enum CodecID codec_id, const char *fmt_name)
  90 {
  91     switch(nb_channels) {
  92     case 1: return CH_LAYOUT_MONO;
  93     case 2: return CH_LAYOUT_STEREO;
  94     case 3: return CH_LAYOUT_SURROUND;
  95     case 4: return CH_LAYOUT_QUAD;
  96     case 5: return CH_LAYOUT_5POINT0;
  97     case 6: return CH_LAYOUT_5POINT1;
  98     case 8: return CH_LAYOUT_7POINT1;
  99     default: return 0;
 100     }
 101 }
 102
 103 static const struct {
 104     const char *name;
 105     int         nb_channels;
 106     int64_t     layout;
 107 } channel_layout_map[] = {
 108     { "mono",        1,  CH_LAYOUT_MONO },
 109     { "stereo",      2,  CH_LAYOUT_STEREO },
 110     { "surround",    3,  CH_LAYOUT_SURROUND },
 111     { "4.0",         4,  CH_LAYOUT_4POINT0 },
 112     { "quad",        4,  CH_LAYOUT_QUAD },
 113     { "5.0",         5,  CH_LAYOUT_5POINT0 },
 114     { "5.0",         5,  CH_LAYOUT_5POINT0_BACK },
 115     { "5.1",         6,  CH_LAYOUT_5POINT1 },
 116     { "5.1",         6,  CH_LAYOUT_5POINT1_BACK },
 117     { "5.1+downmix", 8,  CH_LAYOUT_5POINT1|CH_LAYOUT_STEREO_DOWNMIX, },
 118     { "7.1",         8,  CH_LAYOUT_7POINT1 },
 119     { "7.1(wide)",   8,  CH_LAYOUT_7POINT1_WIDE },
 120     { "7.1+downmix", 10, CH_LAYOUT_7POINT1|CH_LAYOUT_STEREO_DOWNMIX, },
 121     { 0 }
 122 };
 123
 124 void avcodec_get_channel_layout_string(char *buf, int buf_size, int nb_channels, int64_t channel_layout)
 125 {
 126     int i;
 127
 128     if (channel_layout==0)
 129         channel_layout = avcodec_guess_channel_layout(nb_channels, CODEC_ID_NONE, NULL);
 130
 131     for (i=0; channel_layout_map[i].name; i++)
 132         if (nb_channels    == channel_layout_map[i].nb_channels &&
 133             channel_layout == channel_layout_map[i].layout) {
 134             av_strlcpy(buf, channel_layout_map[i].name, buf_size);
 135             return;
 136         }
 137
 138     snprintf(buf, buf_size, "%d channels", nb_channels);
 139     if (channel_layout) {
 140         int i,ch;
 141         av_strlcat(buf, " (", buf_size);
 142         for(i=0,ch=0; i<64; i++) {
 143             if ((channel_layout & (1L<<i))) {
 144                 const char *name = get_channel_name(i);
 145                 if (name) {
 146                     if (ch>0) av_strlcat(buf, "|", buf_size);
 147                     av_strlcat(buf, name, buf_size);
 148                 }
 149                 ch++;
 150             }
 151         }
 152         av_strlcat(buf, ")", buf_size);
 153     }
 154 }
 155
 156 struct AVAudioConvert {
 157     int in_channels, out_channels;
 158     int fmt_pair;
 159 };
 160
 161 AVAudioConvert *av_audio_convert_alloc(enum SampleFormat out_fmt, int out_channels,
 162                                        enum SampleFormat in_fmt, int in_channels,
 163                                        const float *matrix, int flags)
 164 {
 165     AVAudioConvert *ctx;
 166     if (in_channels!=out_channels)
 167         return NULL;  /* FIXME: not supported */
 168     ctx = av_malloc(sizeof(AVAudioConvert));
 169     if (!ctx)
 170         return NULL;
 171     ctx->in_channels = in_channels;
 172     ctx->out_channels = out_channels;
 173     ctx->fmt_pair = out_fmt + SAMPLE_FMT_NB*in_fmt;
 174     return ctx;
 175 }
 176
 177 void av_audio_convert_free(AVAudioConvert *ctx)
 178 {
 179     av_free(ctx);
 180 }
 181
 182 int av_audio_convert(AVAudioConvert *ctx,
 183                            void * const out[6], const int out_stride[6],
 184                      const void * const  in[6], const int  in_stride[6], int len)
 185 {
 186     int ch;
 187
 188     //FIXME optimize common cases
 189
 190     for(ch=0; ch<ctx->out_channels; ch++){
 191         const int is=  in_stride[ch];
 192         const int os= out_stride[ch];
 193         const uint8_t *pi=  in[ch];
 194         uint8_t *po= out[ch];
 195         uint8_t *end= po + os*len;
 196         if(!out[ch])
 197             continue;
 198
 199 #define CONV(ofmt, otype, ifmt, expr)\
 200 if(ctx->fmt_pair == ofmt + SAMPLE_FMT_NB*ifmt){\
 201     do{\
 202         *(otype*)po = expr; pi += is; po += os;\
 203     }while(po < end);\
 204 }
 205
 206 //FIXME put things below under ifdefs so we do not waste space for cases no codec will need
 207 //FIXME rounding and clipping ?
 208
 209              CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_U8 ,  *(const uint8_t*)pi)
 210         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)<<8)
 211         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)<<24)
 212         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
 213         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
 214         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_S16, (*(const int16_t*)pi>>8) + 0x80)
 215         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_S16,  *(const int16_t*)pi)
 216         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_S16,  *(const int16_t*)pi<<16)
 217         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_S16,  *(const int16_t*)pi*(1.0 / (1<<15)))
 218         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_S16,  *(const int16_t*)pi*(1.0 / (1<<15)))
 219         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_S32, (*(const int32_t*)pi>>24) + 0x80)
 220         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_S32,  *(const int32_t*)pi>>16)
 221         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_S32,  *(const int32_t*)pi)
 222         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_S32,  *(const int32_t*)pi*(1.0 / (1<<31)))
 223         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_S32,  *(const int32_t*)pi*(1.0 / (1<<31)))
 224         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_FLT, lrintf(*(const float*)pi * (1<<7)) + 0x80)
 225         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_FLT, lrintf(*(const float*)pi * (1<<15)))
 226         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_FLT, lrintf(*(const float*)pi * (1<<31)))
 227         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_FLT, *(const float*)pi)
 228         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_FLT, *(const float*)pi)
 229         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_DBL, lrint(*(const double*)pi * (1<<7)) + 0x80)
 230         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_DBL, lrint(*(const double*)pi * (1<<15)))
 231         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_DBL, lrint(*(const double*)pi * (1<<31)))
 232         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_DBL, *(const double*)pi)
 233         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_DBL, *(const double*)pi)
 234         else return -1;
 235     }
 236     return 0;
 237 }