audioconvert.c
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1 /*
2  * audio conversion
3  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
28 #include "libavutil/avstring.h"
29 #include "libavutil/libm.h"
30 #include "libavutil/samplefmt.h"
31 #include "avcodec.h"
32 #include "audioconvert.h"
33 
34 #if FF_API_OLD_SAMPLE_FMT
35 const char *avcodec_get_sample_fmt_name(int sample_fmt)
36 {
37  return av_get_sample_fmt_name(sample_fmt);
38 }
39 
40 enum AVSampleFormat avcodec_get_sample_fmt(const char* name)
41 {
42  return av_get_sample_fmt(name);
43 }
44 
45 void avcodec_sample_fmt_string (char *buf, int buf_size, int sample_fmt)
46 {
47  av_get_sample_fmt_string(buf, buf_size, sample_fmt);
48 }
49 #endif
50 
51 uint64_t avcodec_guess_channel_layout(int nb_channels, enum CodecID codec_id, const char *fmt_name)
52 {
53  switch(nb_channels) {
54  case 1: return AV_CH_LAYOUT_MONO;
55  case 2: return AV_CH_LAYOUT_STEREO;
56  case 3: return AV_CH_LAYOUT_SURROUND;
57  case 4: return AV_CH_LAYOUT_QUAD;
58  case 5: return AV_CH_LAYOUT_5POINT0;
59  case 6: return AV_CH_LAYOUT_5POINT1;
60  case 8: return AV_CH_LAYOUT_7POINT1;
61  default: return 0;
62  }
63 }
64 
65 #if FF_API_OLD_AUDIOCONVERT
66 int64_t avcodec_get_channel_layout(const char *name)
67 {
68  return av_get_channel_layout(name);
69 }
70 
71 void avcodec_get_channel_layout_string(char *buf, int buf_size, int nb_channels, int64_t channel_layout)
72 {
73  av_get_channel_layout_string(buf, buf_size, nb_channels, channel_layout);
74 }
75 
76 int avcodec_channel_layout_num_channels(int64_t channel_layout)
77 {
78  return av_get_channel_layout_nb_channels(channel_layout);
79 }
80 #endif
81 
84  int fmt_pair;
85 };
86 
87 AVAudioConvert *av_audio_convert_alloc(enum AVSampleFormat out_fmt, int out_channels,
88  enum AVSampleFormat in_fmt, int in_channels,
89  const float *matrix, int flags)
90 {
91  AVAudioConvert *ctx;
92  if (in_channels!=out_channels)
93  return NULL; /* FIXME: not supported */
94  ctx = av_malloc(sizeof(AVAudioConvert));
95  if (!ctx)
96  return NULL;
97  ctx->in_channels = in_channels;
98  ctx->out_channels = out_channels;
99  ctx->fmt_pair = out_fmt + AV_SAMPLE_FMT_NB*in_fmt;
100  return ctx;
101 }
102 
104 {
105  av_free(ctx);
106 }
107 
109  void * const out[6], const int out_stride[6],
110  const void * const in[6], const int in_stride[6], int len)
111 {
112  int ch;
113 
114  //FIXME optimize common cases
115 
116  for(ch=0; ch<ctx->out_channels; ch++){
117  const int is= in_stride[ch];
118  const int os= out_stride[ch];
119  const uint8_t *pi= in[ch];
120  uint8_t *po= out[ch];
121  uint8_t *end= po + os*len;
122  if(!out[ch])
123  continue;
124 
125 #define CONV(ofmt, otype, ifmt, expr)\
126 if(ctx->fmt_pair == ofmt + AV_SAMPLE_FMT_NB*ifmt){\
127  do{\
128  *(otype*)po = expr; pi += is; po += os;\
129  }while(po < end);\
130 }
131 
132 //FIXME put things below under ifdefs so we do not waste space for cases no codec will need
133 //FIXME rounding ?
134 
135  CONV(AV_SAMPLE_FMT_U8 , uint8_t, AV_SAMPLE_FMT_U8 , *(const uint8_t*)pi)
136  else CONV(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)<<8)
137  else CONV(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)<<24)
138  else CONV(AV_SAMPLE_FMT_FLT, float , AV_SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
139  else CONV(AV_SAMPLE_FMT_DBL, double , AV_SAMPLE_FMT_U8 , (*(const uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
140  else CONV(AV_SAMPLE_FMT_U8 , uint8_t, AV_SAMPLE_FMT_S16, (*(const int16_t*)pi>>8) + 0x80)
141  else CONV(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_S16, *(const int16_t*)pi)
142  else CONV(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_S16, *(const int16_t*)pi<<16)
143  else CONV(AV_SAMPLE_FMT_FLT, float , AV_SAMPLE_FMT_S16, *(const int16_t*)pi*(1.0 / (1<<15)))
144  else CONV(AV_SAMPLE_FMT_DBL, double , AV_SAMPLE_FMT_S16, *(const int16_t*)pi*(1.0 / (1<<15)))
145  else CONV(AV_SAMPLE_FMT_U8 , uint8_t, AV_SAMPLE_FMT_S32, (*(const int32_t*)pi>>24) + 0x80)
146  else CONV(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_S32, *(const int32_t*)pi>>16)
147  else CONV(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_S32, *(const int32_t*)pi)
148  else CONV(AV_SAMPLE_FMT_FLT, float , AV_SAMPLE_FMT_S32, *(const int32_t*)pi*(1.0 / (1U<<31)))
149  else CONV(AV_SAMPLE_FMT_DBL, double , AV_SAMPLE_FMT_S32, *(const int32_t*)pi*(1.0 / (1U<<31)))
150  else CONV(AV_SAMPLE_FMT_U8 , uint8_t, AV_SAMPLE_FMT_FLT, av_clip_uint8( lrintf(*(const float*)pi * (1<<7)) + 0x80))
151  else CONV(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, av_clip_int16( lrintf(*(const float*)pi * (1<<15))))
152  else CONV(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, av_clipl_int32(llrintf(*(const float*)pi * (1U<<31))))
153  else CONV(AV_SAMPLE_FMT_FLT, float , AV_SAMPLE_FMT_FLT, *(const float*)pi)
154  else CONV(AV_SAMPLE_FMT_DBL, double , AV_SAMPLE_FMT_FLT, *(const float*)pi)
155  else CONV(AV_SAMPLE_FMT_U8 , uint8_t, AV_SAMPLE_FMT_DBL, av_clip_uint8( lrint(*(const double*)pi * (1<<7)) + 0x80))
156  else CONV(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, av_clip_int16( lrint(*(const double*)pi * (1<<15))))
157  else CONV(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, av_clipl_int32(llrint(*(const double*)pi * (1U<<31))))
158  else CONV(AV_SAMPLE_FMT_FLT, float , AV_SAMPLE_FMT_DBL, *(const double*)pi)
159  else CONV(AV_SAMPLE_FMT_DBL, double , AV_SAMPLE_FMT_DBL, *(const double*)pi)
160  else return -1;
161  }
162  return 0;
163 }