3 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
5 * This file is part of FFmpeg.
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.
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.
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
23 * @file audioconvert.c
25 * @author Michael Niedermayer <michaelni@gmx.at>
28 #include "audioconvert.h"
30 typedef struct SampleFmtInfo {
35 /** this table gives more information about formats */
36 static const SampleFmtInfo sample_fmt_info[SAMPLE_FMT_NB] = {
37 [SAMPLE_FMT_U8] = { .name = "u8", .bits = 8 },
38 [SAMPLE_FMT_S16] = { .name = "s16", .bits = 16 },
39 [SAMPLE_FMT_S24] = { .name = "s24", .bits = 24 },
40 [SAMPLE_FMT_S32] = { .name = "s32", .bits = 32 },
41 [SAMPLE_FMT_FLT] = { .name = "flt", .bits = 32 }
44 const char *avcodec_get_sample_fmt_name(int sample_fmt)
46 if (sample_fmt < 0 || sample_fmt >= SAMPLE_FMT_NB)
48 return sample_fmt_info[sample_fmt].name;
51 enum SampleFormat avcodec_get_sample_fmt(const char* name)
55 for (i=0; i < SAMPLE_FMT_NB; i++)
56 if (!strcmp(sample_fmt_info[i].name, name))
58 return SAMPLE_FMT_NONE;
61 void avcodec_sample_fmt_string (char *buf, int buf_size, int sample_fmt)
65 snprintf (buf, buf_size, "name " " depth");
66 else if (sample_fmt < SAMPLE_FMT_NB) {
67 SampleFmtInfo info= sample_fmt_info[sample_fmt];
68 snprintf (buf, buf_size, "%-6s" " %2d ", info.name, info.bits);
72 int av_audio_convert(void *maybe_dspcontext_or_something_av_convert_specific,
73 void *out[6], int out_stride[6], enum SampleFormat out_fmt,
74 void * in[6], int in_stride[6], enum SampleFormat in_fmt, int len){
76 const int isize= FFMIN( in_fmt+1, 4);
77 const int osize= FFMIN(out_fmt+1, 4);
78 const int fmt_pair= out_fmt + 5*in_fmt;
80 //FIXME optimize common cases
82 for(ch=0; ch<6; ch++){
83 const int is= in_stride[ch] * isize;
84 const int os= out_stride[ch] * osize;
87 uint8_t *end= po + os;
91 #define CONV(ofmt, otype, ifmt, expr)\
92 if(fmt_pair == ofmt + 5*ifmt){\
94 *(otype*)po = expr; pi += is; po += os;\
98 //FIXME put things below under ifdefs so we do not waste space for cases no codec will need
99 //FIXME rounding and clipping ?
101 CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_U8 , *(uint8_t*)pi)
102 else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)<<8)
103 else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)<<24)
104 else CONV(SAMPLE_FMT_FLT, float , SAMPLE_FMT_U8 , (*(uint8_t*)pi - 0x80)*(1.0 / (1<<7)))
105 else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_S16, (*(int16_t*)pi>>8) + 0x80)
106 else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_S16, *(int16_t*)pi)
107 else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_S16, *(int16_t*)pi<<16)
108 else CONV(SAMPLE_FMT_FLT, float , SAMPLE_FMT_S16, *(int16_t*)pi*(1.0 / (1<<15)))
109 else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_S32, (*(int32_t*)pi>>24) + 0x80)
110 else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_S32, *(int32_t*)pi>>16)
111 else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_S32, *(int32_t*)pi)
112 else CONV(SAMPLE_FMT_FLT, float , SAMPLE_FMT_S32, *(int32_t*)pi*(1.0 / (1<<31)))
113 else CONV(SAMPLE_FMT_U8 , uint8_t, SAMPLE_FMT_FLT, lrintf(*(float*)pi * (1<<7)) + 0x80)
114 else CONV(SAMPLE_FMT_S16, int16_t, SAMPLE_FMT_FLT, lrintf(*(float*)pi * (1<<15)))
115 else CONV(SAMPLE_FMT_S32, int32_t, SAMPLE_FMT_FLT, lrintf(*(float*)pi * (1<<31)))
116 else CONV(SAMPLE_FMT_FLT, float , SAMPLE_FMT_FLT, *(float*)pi)