37 seed = seed* 1664525 + 1013904223;
43 v = ((double)seed) / UINT_MAX;
44 seed = seed*1664525 + 1013904223;
45 v-= ((double)seed) / UINT_MAX;
60 v = (- tmp[
i] + 2*tmp[i+1] - tmp[i+2]) / sqrt(6);
120 for (j=0; j<f->
len; j++)
127 av_log(s,
AV_LOG_WARNING,
"Requested noise shaping dither not available at this sampling rate, using triangular hp dither\n");
134 #define TEMPLATE_DITHER_S16 136 #undef TEMPLATE_DITHER_S16 138 #define TEMPLATE_DITHER_S32 140 #undef TEMPLATE_DITHER_S32 142 #define TEMPLATE_DITHER_FLT 144 #undef TEMPLATE_DITHER_FLT 146 #define TEMPLATE_DITHER_DBL 148 #undef TEMPLATE_DITHER_DBL
int out_sample_rate
output sample rate
enum AVResampleDitherMethod method
#define AV_LOG_WARNING
Something somehow does not look correct.
float ns_scale
Noise shaping dither scale.
float ns_coeffs[NS_TAPS]
Noise shaping filter coefficients.
#define av_assert0(cond)
assert() equivalent, that is always enabled.
float ns_errors[SWR_CH_MAX][2 *NS_TAPS]
int swri_get_dither(SwrContext *s, void *dst, int len, unsigned seed, enum AVSampleFormat noise_fmt)
#define i(width, name, range_min, range_max)
int output_sample_bits
the number of used output bits, needed to scale dither correctly
av_cold int swri_dither_init(SwrContext *s, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt)
The libswresample context.
simple assert() macros that are a bit more flexible than ISO C assert().
float ns_scale_1
Noise shaping dither scale^-1.
float noise_scale
Noise scale.
AVSampleFormat
Audio sample formats.
int ns_pos
Noise shaping dither position.
struct DitherContext dither
int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
Return number of bytes per sample.
enum AVSampleFormat av_get_packed_sample_fmt(enum AVSampleFormat sample_fmt)
Get the packed alternative form of the given sample format.
static const struct PPFilter filters[]
#define av_malloc_array(a, b)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
int ns_taps
Noise shaping dither taps.