#define NELLY_BIT_CAP 6
#define NELLY_BASE_OFF 4228
#define NELLY_BASE_SHIFT 19
-#define NELLY_SAMPLES 256
+#define NELLY_SAMPLES (2 * NELLY_BUF_LEN)
static const float dequantization_table[127] = {
0.0000000000,-0.8472560048, 0.7224709988, -1.5247479677, -0.4531480074, 0.3753609955, 1.4717899561,
typedef struct NellyMoserDecodeContext {
AVCodecContext* avctx;
- float float_buf[NELLY_SAMPLES];
- float state[64];
+ DECLARE_ALIGNED_16(float,float_buf[NELLY_SAMPLES]);
+ float state[128];
AVRandomState random_state;
GetBitContext gb;
int add_bias;
- int scale_bias;
+ float scale_bias;
DSPContext dsp;
- FFTContext fftc;
+ MDCTContext imdct_ctx;
+ DECLARE_ALIGNED_16(float,imdct_tmp[NELLY_BUF_LEN]);
+ DECLARE_ALIGNED_16(float,imdct_out[NELLY_BUF_LEN * 2]);
} NellyMoserDecodeContext;
-
-DECLARE_ALIGNED_16(float,sine_window[128]);
-DECLARE_ALIGNED_16(float,tcos[64]);
-DECLARE_ALIGNED_16(float,tsin[64]);
-DECLARE_ALIGNED_16(float,cos_tab[64]);
+static DECLARE_ALIGNED_16(float,sine_window[128]);
static inline int signed_shift(int i, int shift) {
if (shift > 0)
return i >> -shift;
}
-static void antialias(float *buf, float *audio)
-{
- int i, end, mid_hi, mid_lo;
-
- end = NELLY_BUF_LEN-1;
- mid_hi = NELLY_BUF_LEN/2;
- mid_lo = mid_hi-1;
- for (i = 0; i < NELLY_BUF_LEN/4; i++) {
- audio[2*i] = buf[2*i ]*tcos[i ] - buf[end-2*i]*tsin[i];
- audio[2*i+1] = -(buf[end-2*i ]*tcos[i ] + buf[2*i ]*tsin[i]);
- audio[end-2*i-1]= buf[end-2*i-1]*tcos[mid_lo-i] - buf[2*i+1 ]*tsin[mid_lo-i];
- audio[end-2*i ]= -(buf[2*i+1 ]*tcos[mid_lo-i] + buf[end-2*i]*tsin[mid_lo-i]);
- }
-}
-
-static void complex2signal(float *audio)
+static void overlap_and_window(NellyMoserDecodeContext *s, float *state, float *audio, float *a_in)
{
- int i, end, mid_hi, mid_lo;
- float *aptr, *sigptr, a, b, c, d, e, f, g;
-
- end = NELLY_BUF_LEN-1;
- mid_hi = NELLY_BUF_LEN/2;
- mid_lo = mid_hi-1;
-
- a = -audio[end];
- b = audio[end-1];
- c = -audio[1];
- d = cos_tab[0];
- e = audio[0];
- f = cos_tab[mid_lo];
- g = cos_tab[1];
-
- audio[0] = d*e;
- audio[1] = b*g-a*f;
- audio[end-1] = a*g+b*f;
- audio[end] = c*(-d);
-
- aptr = audio+end-2;
- sigptr = cos_tab+mid_hi-1;
-
- for (i = 3; i < NELLY_BUF_LEN/2; i += 2) {
- a = audio[i-1];
- b = -audio[i];
- c = cos_tab[i/2];
- d = *sigptr;
- e = *(aptr-1);
- f = -(*aptr);
-
- audio[i-1] = a*c+b*d;
- *aptr = a*d-b*c;
-
- a = cos_tab[(i/2)+1];
- b = *(sigptr-1);
-
- *(aptr-1) = b*e+a*f;
- audio[i] = a*e-b*f;
-
- sigptr--;
- aptr -= 2;
- }
-}
-
-static void overlap_and_window(NellyMoserDecodeContext *s, float *state, float *audio)
-{
- int bot, mid_up, mid_down, top;
- float s_bot, s_top;
+ int bot, top;
bot = 0;
top = NELLY_BUF_LEN-1;
- mid_up = NELLY_BUF_LEN/2;
- mid_down = (NELLY_BUF_LEN/2)-1;
-
- while (bot < NELLY_BUF_LEN/4) {
- s_bot = audio[bot];
- s_top = audio[top];
- audio[bot] = (audio[mid_up]*sine_window[bot]-state[bot ]*sine_window[top])/s->scale_bias + s->add_bias;
- audio[top] = (-state[bot ]*sine_window[bot]-audio[mid_up]*sine_window[top])/s->scale_bias + s->add_bias;
- state[bot] = audio[mid_down];
- audio[mid_down] = (s_top *sine_window[mid_down]-state[mid_down]*sine_window[mid_up])/s->scale_bias + s->add_bias;
- audio[mid_up ] = (-state[mid_down]*sine_window[mid_down]-s_top *sine_window[mid_up])/s->scale_bias + s->add_bias;
- state[mid_down] = s_bot;
+ while (bot < NELLY_BUF_LEN) {
+ audio[bot] = a_in [bot]*sine_window[bot]
+ +state[bot]*sine_window[top] + s->add_bias;
bot++;
- mid_up++;
- mid_down--;
top--;
}
+ memcpy(state, a_in + NELLY_BUF_LEN, sizeof(float)*NELLY_BUF_LEN);
}
static int sum_bits(short *buf, short shift, short off)
}
-static void get_sample_bits(float *buf, int *bits)
+static void get_sample_bits(const float *buf, int *bits)
{
int i, j;
short sbuf[128];
}
}
-void nelly_decode_block(NellyMoserDecodeContext *s, unsigned char block[NELLY_BLOCK_LEN], float audio[NELLY_SAMPLES])
+void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NELLY_BLOCK_LEN], float audio[NELLY_SAMPLES])
{
int i,j;
- float buf[NELLY_BUF_LEN], pows[NELLY_BUF_LEN];
+ float buf[NELLY_FILL_LEN], pows[NELLY_FILL_LEN];
float *aptr, *bptr, *pptr, val, pval;
int bits[NELLY_BUF_LEN];
unsigned char v;
for (i=0 ; i<NELLY_BANDS ; i++) {
if (i > 0)
val += nelly_delta_table[get_bits(&s->gb, 5)];
- pval = pow(2, val/2048);
+ pval = -pow(2, val/2048) * s->scale_bias;
for (j = 0; j < nelly_band_sizes_table[i]; j++) {
*bptr++ = val;
*pptr++ = pval;
}
- memset(&buf[NELLY_FILL_LEN],0,4*sizeof(float));
- memset(&pows[NELLY_FILL_LEN],0,4*sizeof(float));
-
get_sample_bits(buf, bits);
for (i = 0; i < 2; i++) {
- aptr = audio+i*128;
+ aptr = audio + i * NELLY_BUF_LEN;
+
init_get_bits(&s->gb, block, NELLY_BLOCK_LEN * 8);
skip_bits(&s->gb, NELLY_HEADER_BITS + i*NELLY_DETAIL_BITS);
for (j = 0; j < NELLY_FILL_LEN; j++) {
if (bits[j] <= 0) {
- buf[j] = M_SQRT1_2*pows[j];
+ aptr[j] = M_SQRT1_2*pows[j];
if (av_random(&s->random_state) & 1)
- buf[j] *= -1.0;
+ aptr[j] *= -1.0;
} else {
v = get_bits(&s->gb, bits[j]);
- buf[j] = dequantization_table[(1<<bits[j])-1+v]*pows[j];
+ aptr[j] = dequantization_table[(1<<bits[j])-1+v]*pows[j];
}
}
-
- antialias(buf, aptr);
- ff_fft_permute(&s->fftc, (FFTComplex*)aptr);
- ff_fft_calc(&s->fftc, (FFTComplex*)aptr);
- complex2signal(aptr);
- overlap_and_window(s, s->state, aptr);
+ memset(&aptr[NELLY_FILL_LEN], 0,
+ (NELLY_BUF_LEN - NELLY_FILL_LEN) * sizeof(float));
+
+ s->imdct_ctx.fft.imdct_calc(&s->imdct_ctx, s->imdct_out,
+ aptr, s->imdct_tmp);
+ /* XXX: overlapping and windowing should be part of a more
+ generic imdct function */
+ overlap_and_window(s, s->state, aptr, s->imdct_out);
}
}
-static int decode_init(AVCodecContext * avctx) {
+static av_cold int decode_init(AVCodecContext * avctx) {
NellyMoserDecodeContext *s = avctx->priv_data;
int i;
- float alpha;
s->avctx = avctx;
av_init_random(0, &s->random_state);
- ff_fft_init(&s->fftc, 6, 1);
+ ff_mdct_init(&s->imdct_ctx, 8, 1);
+
dsputil_init(&s->dsp, avctx);
if(s->dsp.float_to_int16 == ff_float_to_int16_c) {
s->add_bias = 385;
- s->scale_bias = 32768;
+ s->scale_bias = 1.0/(8*32768);
} else {
s->add_bias = 0;
- s->scale_bias = 1;
+ s->scale_bias = 1.0/(1*8);
}
/* Generate overlap window */
sine_window[i] = sin((i + 0.5) / 256.0 * M_PI);
}
- /* Generate tables */
- if (!tcos[0])
- for(i=0;i<64;i++) {
- alpha = 2*M_PI * (i + 1.0 / 4.0) / 256;
- tcos[i] = cos(alpha);
- tsin[i] = -sin(alpha);
- cos_tab[i] = cos(i/128.0*M_PI)/8.0;
- }
-
return 0;
}
static int decode_tag(AVCodecContext * avctx,
void *data, int *data_size,
- uint8_t * buf, int buf_size) {
+ const uint8_t * buf, int buf_size) {
NellyMoserDecodeContext *s = avctx->priv_data;
int blocks, i;
int16_t* samples;
blocks = 2; break;
case 256: // 22050Hz
blocks = 4; break;
+ case 512: // 44100Hz
+ blocks = 8; break;
default:
- av_log(avctx, AV_LOG_DEBUG, "Tag size %d unknown, report sample!\n", buf_size);
+ av_log(avctx, AV_LOG_ERROR, "Tag size %d unknown, report sample!\n", buf_size);
return buf_size;
}
*data_size += NELLY_SAMPLES*sizeof(int16_t);
}
- return blocks*NELLY_SAMPLES*sizeof(int16_t);
+ return buf_size;
}
-static int decode_end(AVCodecContext * avctx) {
+static av_cold int decode_end(AVCodecContext * avctx) {
NellyMoserDecodeContext *s = avctx->priv_data;
- ff_fft_end(&s->fftc);
+ ff_mdct_end(&s->imdct_ctx);
return 0;
}
projects / ffmpeg / blobdiff