Make most of E-AC-3 work without breaking regression tests.

[ffmpeg] / libavcodec / nellymoserdec.c

diff --git a/libavcodec/nellymoserdec.c b/libavcodec/nellymoserdec.c
index fc57f2d61ffbb5cc6dab9ca924364a8ca28493c0..470465d9d285a22ca195d5aba129c608ee3e296b 100644 (file)
--- a/libavcodec/nellymoserdec.c
+++ b/libavcodec/nellymoserdec.c
@@ -96,7 +96,7 @@ typedef struct NellyMoserDecodeContext {
     AVRandomState   random_state;
     GetBitContext   gb;
     int             add_bias;
-    int             scale_bias;
+    float           scale_bias;
     DSPContext      dsp;
     MDCTContext     imdct_ctx;
     DECLARE_ALIGNED_16(float,imdct_tmp[NELLY_BUF_LEN]);
@@ -114,13 +114,14 @@ static inline int signed_shift(int i, int shift) {
 
 static void overlap_and_window(NellyMoserDecodeContext *s, float *state, float *audio, float *a_in)
 {
-    int bot, top, top2;
+    int bot, top;
 
     bot = 0;
     top = NELLY_BUF_LEN-1;
 
     while (bot < NELLY_BUF_LEN) {
-        audio[bot] = ( a_in[bot]*sine_window[bot]+state[bot]*sine_window[top])/s->scale_bias + s->add_bias;
+        audio[bot] = a_in [bot]*sine_window[bot]
+                    +state[bot]*sine_window[top] + s->add_bias;
 
         bot++;
         top--;
@@ -279,7 +280,7 @@ void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NE
     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;
@@ -298,11 +299,11 @@ void nelly_decode_block(NellyMoserDecodeContext *s, const unsigned char block[NE
         for (j = 0; j < NELLY_FILL_LEN; j++) {
             if (bits[j] <= 0) {
                 aptr[j] = M_SQRT1_2*pows[j];
-                if (!(av_random(&s->random_state) & 1))
+                if (av_random(&s->random_state) & 1)
                     aptr[j] *= -1.0;
             } else {
                 v = get_bits(&s->gb, bits[j]);
-                aptr[j] = -dequantization_table[(1<<bits[j])-1+v]*pows[j];
+                aptr[j] = dequantization_table[(1<<bits[j])-1+v]*pows[j];
             }
         }
         memset(&aptr[NELLY_FILL_LEN], 0,
@@ -328,10 +329,10 @@ static av_cold int decode_init(AVCodecContext * avctx) {
 
     if(s->dsp.float_to_int16 == ff_float_to_int16_c) {
         s->add_bias = 385;
-        s->scale_bias = 8*32768;
+        s->scale_bias = 1.0/(8*32768);
     } else {
         s->add_bias = 0;
-        s->scale_bias = 1*8;
+        s->scale_bias = 1.0/(1*8);
     }
 
     /* Generate overlap window */