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 audioconvert.c
  24  * audio conversion
  25  * @author Michael Niedermayer <michaelni@gmx.at>
  26  */
  27
  28 #include "avcodec.h"
  29 #include "audioconvert.h"
  30
  31 typedef struct SampleFmtInfo {
  32     const char *name;
  33     int bits;
  34 } SampleFmtInfo;
  35
  36 /** this table gives more information about formats */
  37 static const SampleFmtInfo sample_fmt_info[SAMPLE_FMT_NB] = {
  38     [SAMPLE_FMT_U8]  = { .name = "u8",  .bits = 8 },
  39     [SAMPLE_FMT_S16] = { .name = "s16", .bits = 16 },
  40     [SAMPLE_FMT_S32] = { .name = "s32", .bits = 32 },
  41     [SAMPLE_FMT_FLT] = { .name = "flt", .bits = 32 },
  42     [SAMPLE_FMT_DBL] = { .name = "dbl", .bits = 64 },
  43 };
  44
  45 const char *avcodec_get_sample_fmt_name(int sample_fmt)
  46 {
  47     if (sample_fmt < 0 || sample_fmt >= SAMPLE_FMT_NB)
  48         return NULL;
  49     return sample_fmt_info[sample_fmt].name;
  50 }
  51
  52 enum SampleFormat avcodec_get_sample_fmt(const char* name)
  53 {
  54     int i;
  55
  56     for (i=0; i < SAMPLE_FMT_NB; i++)
  57         if (!strcmp(sample_fmt_info[i].name, name))
  58             return i;
  59     return SAMPLE_FMT_NONE;
  60 }
  61
  62 void avcodec_sample_fmt_string (char *buf, int buf_size, int sample_fmt)
  63 {
  64     /* print header */
  65     if (sample_fmt < 0)
  66         snprintf (buf, buf_size, "name  " " depth");
  67     else if (sample_fmt < SAMPLE_FMT_NB) {
  68         SampleFmtInfo info= sample_fmt_info[sample_fmt];
  69         snprintf (buf, buf_size, "%-6s" "   %2d ", info.name, info.bits);
  70     }
  71 }
  72
  73 struct AVAudioConvert {
  74     int in_channels, out_channels;
  75     int fmt_pair;
  76 };
  77
  78 AVAudioConvert *av_audio_convert_alloc(enum SampleFormat out_fmt, int out_channels,
  79                                        enum SampleFormat in_fmt, int in_channels,
  80                                        const const float *matrix, int flags)
  81 {
  82     AVAudioConvert *ctx;
  83     if (in_channels!=out_channels)
  84         return NULL;  /* FIXME: not supported */
  85     ctx = av_malloc(sizeof(AVAudioConvert));
  86     if (!ctx)
  87         return NULL;
  88     ctx->in_channels = in_channels;
  89     ctx->out_channels = out_channels;
  90     ctx->fmt_pair = out_fmt + SAMPLE_FMT_NB*in_fmt;
  91     return ctx;
  92 }
  93
  94 void av_audio_convert_free(AVAudioConvert *ctx)
  95 {
  96     av_free(ctx);
  97 }
  98
  99 int av_audio_convert(AVAudioConvert *ctx,
 100                            void * const out[6], const int out_stride[6],
 101                      const void * const  in[6], const int  in_stride[6], int len)
 102 {
 103     int ch;
 104
 105     //FIXME optimize common cases
 106
 107     for(ch=0; ch<ctx->out_channels; ch++){
 108         const int is=  in_stride[ch];
 109         const int os= out_stride[ch];
 110         uint8_t *pi=  in[ch];
 111         uint8_t *po= out[ch];
 112         uint8_t *end= po + os*len;
 113         if(!out[ch])
 114             continue;
 115
 116 #define CONV(ofmt, otype, ifmt, expr)\
 117 if(ctx->fmt_pair == ofmt + SAMPLE_FMT_NB*ifmt){\
 118     do{\
 119         *(otype*)po = expr; pi += is; po += os;\
 120     }while(po < end);\
 121 }
 122
 123 //FIXME put things below under ifdefs so we do not waste space for cases no codec will need
 124 //FIXME rounding and clipping ?
 125
 126              CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_U8 ,  *(uint8_t*)pi)
 127         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)<<8)
 128         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)<<24)
 129         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
 130         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
 131         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_S16, (*(int16_t*)pi>>8) + 0x80)
 132         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_S16,  *(int16_t*)pi)
 133         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_S16,  *(int16_t*)pi<<16)
 134         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_S16,  *(int16_t*)pi*(1.0 / (1<<15)))
 135         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_S16,  *(int16_t*)pi*(1.0 / (1<<15)))
 136         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_S32, (*(int32_t*)pi>>24) + 0x80)
 137         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_S32,  *(int32_t*)pi>>16)
 138         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_S32,  *(int32_t*)pi)
 139         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_S32,  *(int32_t*)pi*(1.0 / (1<<31)))
 140         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_S32,  *(int32_t*)pi*(1.0 / (1<<31)))
 141         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_FLT, lrintf(*(float*)pi * (1<<7)) + 0x80)
 142         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_FLT, lrintf(*(float*)pi * (1<<15)))
 143         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_FLT, lrintf(*(float*)pi * (1<<31)))
 144         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_FLT, *(float*)pi)
 145         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_FLT, *(float*)pi)
 146         else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_DBL, lrint(*(double*)pi * (1<<7)) + 0x80)
 147         else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_DBL, lrint(*(double*)pi * (1<<15)))
 148         else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_DBL, lrint(*(double*)pi * (1<<31)))
 149         else CONV(SAMPLE_FMT_FLT, float  , SAMPLE_FMT_DBL, *(double*)pi)
 150         else CONV(SAMPLE_FMT_DBL, double , SAMPLE_FMT_DBL, *(double*)pi)
 151         else return -1;
 152     }
 153     return 0;
 154 }