52 #define FFT_FIXED_32 1 58 50529027, 44278013, 39403370, 32292987, 27356480, 23729101, 20951060, 18755316
69 int temp, temp1, temp2, temp3, temp4, temp5, temp6, temp7;
71 mul = (dynrng & 0x1f) + 0x20;
74 round = 1 << (shift-1);
75 for (i=0; i<
len; i+=8) {
78 temp1 = src[i+1] * mul;
80 temp2 = src[i+2] * mul;
82 temp1 = temp1 +
round;
84 temp3 = src[i+3] * mul;
85 temp2 = temp2 +
round;
87 dst[i+1] = temp1 >>
shift;
88 temp4 = src[i + 4] * mul;
89 temp3 = temp3 +
round;
90 dst[i+2] = temp2 >>
shift;
92 temp5 = src[i+5] * mul;
93 temp4 = temp4 +
round;
94 dst[i+3] = temp3 >>
shift;
95 temp6 = src[i+6] * mul;
97 dst[i+4] = temp4 >>
shift;
98 temp5 = temp5 +
round;
99 temp7 = src[i+7] * mul;
100 temp6 = temp6 +
round;
102 dst[i+5] = temp5 >>
shift;
103 temp7 = temp7 +
round;
104 dst[i+6] = temp6 >>
shift;
105 dst[i+7] = temp7 >>
shift;
111 for (i=0; i<
len; i+=8) {
113 dst[
i] = src[
i ] * mul;
114 dst[i+1] = src[i+1] * mul;
115 dst[i+2] = src[i+2] * mul;
116 dst[i+3] = src[i+3] * mul;
117 dst[i+4] = src[i+4] * mul;
118 dst[i+5] = src[i+5] * mul;
119 dst[i+6] = src[i+6] * mul;
120 dst[i+7] = src[i+7] * mul;
130 int out_ch,
int in_ch,
int len)
135 for (i = 0; i <
len; i++) {
137 for (j = 0; j < in_ch; j++) {
138 v0 += samples[j][
i] * matrix[0][j];
139 v1 += samples[j][
i] * matrix[1][j];
141 samples[0][
i] = (v0+2048)>>12;
142 samples[1][
i] = (v1+2048)>>12;
144 }
else if (out_ch == 1) {
145 for (i = 0; i <
len; i++) {
147 for (j = 0; j < in_ch; j++)
148 v0 += samples[j][i] * matrix[0][j];
149 samples[0][
i] = (v0+2048)>>12;
158 {
"cons_noisegen",
"enable consistent noise generation",
OFFSET(consistent_noise_generation),
AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1,
PAR },
159 {
"drc_scale",
"percentage of dynamic range compression to apply",
OFFSET(drc_scale),
AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0,
PAR },
160 {
"heavy_compr",
"enable heavy dynamic range compression",
OFFSET(heavy_compression),
AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1,
PAR },
175 .priv_data_size =
sizeof (AC3DecodeContext),
static const AVClass ac3_decoder_class
static int shift(int a, int b)
#define LIBAVUTIL_VERSION_INT
static av_cold int init(AVCodecContext *avctx)
const char * av_default_item_name(void *ptr)
Return the context name.
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
static void scale_coefs(int32_t *dst, const int32_t *src, int dynrng, int len)
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
static av_cold int ac3_decode_end(AVCodecContext *avctx)
Uninitialize the AC-3 decoder.
#define i(width, name, range_min, range_max)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
const char * name
Name of the codec implementation.
static av_always_inline av_const double round(double x)
static int ac3_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Decode a single AC-3 frame.
AVCodec ff_ac3_fixed_decoder
AVSampleFormat
Audio sample formats.
static const AVOption options[]
static const int end_freq_inv_tab[8]
Describe the class of an AVClass context structure.
static av_const int sign_extend(int val, unsigned bits)
static void ac3_downmix_c_fixed16(int16_t **samples, int16_t **matrix, int out_ch, int in_ch, int len)
Downmix samples from original signal to stereo or mono (this is for 16-bit samples and fixed point de...
static av_cold int ac3_decode_init(AVCodecContext *avctx)
AVCodec initialization.
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.