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libavcodec/fmtconvert.c

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00001 /*
00002  * Format Conversion Utils
00003  * Copyright (c) 2000, 2001 Fabrice Bellard
00004  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00023 #include "avcodec.h"
00024 #include "fmtconvert.h"
00025 
00026 static void int32_to_float_fmul_scalar_c(float *dst, const int *src, float mul, int len){
00027     int i;
00028     for(i=0; i<len; i++)
00029         dst[i] = src[i] * mul;
00030 }
00031 
00032 static av_always_inline int float_to_int16_one(const float *src){
00033     return av_clip_int16(lrintf(*src));
00034 }
00035 
00036 static void float_to_int16_c(int16_t *dst, const float *src, long len)
00037 {
00038     int i;
00039     for(i=0; i<len; i++)
00040         dst[i] = float_to_int16_one(src+i);
00041 }
00042 
00043 static void float_to_int16_interleave_c(int16_t *dst, const float **src,
00044                                         long len, int channels)
00045 {
00046     int i,j,c;
00047     if(channels==2){
00048         for(i=0; i<len; i++){
00049             dst[2*i]   = float_to_int16_one(src[0]+i);
00050             dst[2*i+1] = float_to_int16_one(src[1]+i);
00051         }
00052     }else{
00053         for(c=0; c<channels; c++)
00054             for(i=0, j=c; i<len; i++, j+=channels)
00055                 dst[j] = float_to_int16_one(src[c]+i);
00056     }
00057 }
00058 
00059 void ff_float_interleave_c(float *dst, const float **src, unsigned int len,
00060                            int channels)
00061 {
00062     int j, c;
00063     unsigned int i;
00064     if (channels == 2) {
00065         for (i = 0; i < len; i++) {
00066             dst[2*i]   = src[0][i];
00067             dst[2*i+1] = src[1][i];
00068         }
00069     } else if (channels == 1 && len < INT_MAX / sizeof(float)) {
00070         memcpy(dst, src[0], len * sizeof(float));
00071     } else {
00072         for (c = 0; c < channels; c++)
00073             for (i = 0, j = c; i < len; i++, j += channels)
00074                 dst[j] = src[c][i];
00075     }
00076 }
00077 
00078 av_cold void ff_fmt_convert_init(FmtConvertContext *c, AVCodecContext *avctx)
00079 {
00080     c->int32_to_float_fmul_scalar = int32_to_float_fmul_scalar_c;
00081     c->float_to_int16             = float_to_int16_c;
00082     c->float_to_int16_interleave  = float_to_int16_interleave_c;
00083     c->float_interleave           = ff_float_interleave_c;
00084 
00085     if (ARCH_ARM) ff_fmt_convert_init_arm(c, avctx);
00086     if (HAVE_ALTIVEC) ff_fmt_convert_init_altivec(c, avctx);
00087     if (HAVE_MMX) ff_fmt_convert_init_x86(c, avctx);
00088 }
00089 
00090 /* ffdshow custom code */
00091 void float_interleave(float *dst, const float **src, long len, int channels)
00092 {
00093     int i,j,c;
00094     if(channels==2){
00095         for(i=0; i<len; i++){
00096             dst[2*i]   = src[0][i] / 32768.0f;
00097             dst[2*i+1] = src[1][i] / 32768.0f;
00098         }
00099     }else{
00100         for(c=0; c<channels; c++)
00101             for(i=0, j=c; i<len; i++, j+=channels)
00102                 dst[j] = src[c][i] / 32768.0f;
00103     }
00104 }
00105 
00106 void float_interleave_noscale(float *dst, const float **src, long len, int channels)
00107 {
00108     int i,j,c;
00109     if(channels==2){
00110         for(i=0; i<len; i++){
00111             dst[2*i]   = src[0][i];
00112             dst[2*i+1] = src[1][i];
00113         }
00114     }else{
00115         for(c=0; c<channels; c++)
00116             for(i=0, j=c; i<len; i++, j+=channels)
00117                 dst[j] = src[c][i];
00118     }
00119 }

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