以下是此处afade
acrossfade
和tri
select triangular, linear slope (default)
qsin
select quarter of sine wave
hsin
select half of sine wave
esin
select exponential sine wave
log
select logarithmic
ipar
select inverted parabola
qua
select quadratic
cub
select cubic
squ
select square root
cbr
select cubic root
par
select parabola
exp
select exponential
iqsin
select inverted quarter of sine wave
ihsin
select inverted half of sine wave
dese
select double-exponential seat
desi
select double-exponential sigmoid
过滤器的可能曲线列表
libavfilter/af_afade.c
以下是switch (curve) {
case QSIN:
gain = sin(gain * M_PI / 2.0);
break;
case IQSIN:
/* 0.6... = 2 / M_PI */
gain = 0.6366197723675814 * asin(gain);
break;
case ESIN:
gain = 1.0 - cos(M_PI / 4.0 * (CUBE(2.0*gain - 1) + 1));
break;
case HSIN:
gain = (1.0 - cos(gain * M_PI)) / 2.0;
break;
case IHSIN:
/* 0.3... = 1 / M_PI */
gain = 0.3183098861837907 * acos(1 - 2 * gain);
break;
case EXP:
/* -11.5... = 5*ln(0.1) */
gain = exp(-11.512925464970227 * (1 - gain));
break;
case LOG:
gain = av_clipd(1 + 0.2 * log10(gain), 0, 1.0);
break;
case PAR:
gain = 1 - sqrt(1 - gain);
break;
case IPAR:
gain = (1 - (1 - gain) * (1 - gain));
break;
case QUA:
gain *= gain;
break;
case CUB:
gain = CUBE(gain);
break;
case SQU:
gain = sqrt(gain);
break;
case CBR:
gain = cbrt(gain);
break;
case DESE:
gain = gain <= 0.5 ? cbrt(2 * gain) / 2: 1 - cbrt(2 * (1 - gain)) / 2;
break;
case DESI:
gain = gain <= 0.5 ? CUBE(2 * gain) / 2: 1 - CUBE(2 * (1 - gain)) / 2;
break;
}
的代码:
C:\Folder> bash
User@Computer:/mnt/c/Folder$ g++ hello_world.cpp -o hello_world
User@Computer:/mnt/c/Folder$ ./hello_world
它们看起来如何?他们听起来怎么样?哪一个推荐用于fadein + fadeout和crossfade?就个人而言,我只是想避免音频点击,也许交叉淡化在这里有点过分。
相关链接:https://ffmpeg.org/ffmpeg-filters.html#afade-1。不知道大胆的名字如何转化为ffmpeg名称。