[FFmpeg-soc] [soc]: r3565 - mlp/mlpenc.c

[ramiro]

Author: ramiro
Date: Sun Aug 24 05:15:16 2008
New Revision: 3565

Log:
Remove any code that tries to calculate some shift for the matrices.
If that ever worked, it was pure luck.
Copy matrix shift with restart frame parameters and use it for quant_step_size().

Modified:
   mlp/mlpenc.c

Modified: mlp/mlpenc.c
==============================================================================
--- mlp/mlpenc.c	(original)
+++ mlp/mlpenc.c	Sun Aug 24 05:15:16 2008
@@ -706,6 +706,7 @@ static void determine_quant_step_size(ML
 {
     DecodingParams *dp = ctx->cur_decoding_params;
     RestartHeader  *rh = ctx->restart_header;
+    MatrixParams *mp = &dp->matrix_params;
     int32_t *sample_buffer = ctx->sample_buffer;
     int32_t sample_mask[MAX_CHANNELS];
     unsigned int channel;
@@ -721,7 +722,7 @@ static void determine_quant_step_size(ML
     }
 
     for (channel = 0; channel <= rh->max_channel; channel++)
-        dp->quant_step_size[channel] = number_trailing_zeroes(sample_mask[channel]);
+        dp->quant_step_size[channel] = number_trailing_zeroes(sample_mask[channel]) - mp->shift[channel];
 }
 
 static void copy_filter_params(FilterParams *dst, FilterParams *src)
@@ -923,40 +924,18 @@ static void code_matrix_coeffs(MLPEncode
 {
     DecodingParams *dp = ctx->cur_decoding_params;
     MatrixParams *mp = &dp->matrix_params;
-    int32_t min = INT32_MAX, max = INT32_MIN;
     int32_t coeff_mask = 0;
     unsigned int channel;
-    unsigned int shift;
     unsigned int bits;
 
     for (channel = 0; channel < ctx->num_channels; channel++) {
         int32_t coeff = mp->coeff[mat][channel];
-
-        if (coeff < min)
-            min = coeff;
-        if (coeff > max)
-            max = coeff;
-
         coeff_mask |= coeff;
     }
 
-    shift = FFMAX(0, FFMAX(number_sbits(min), number_sbits(max)) - 16);
-
-    if (shift) {
-        for (channel = 0; channel < ctx->num_channels; channel++) {
-            mp->coeff[mat][channel] >>= shift;
-            mp->forco[mat][channel] >>= shift;
-        }
-
-        coeff_mask >>= shift;
-    }
-
     for (bits = 0; bits < 14 && !(coeff_mask & (1<<bits)); bits++);
 
     mp->fbits   [mat] = 14 - bits;
-
-    for (channel = 0; channel < ctx->num_channels; channel++)
-        mp->shift[channel] = shift;
 }
 
 /** Determines best coefficients to use for the lossless matrix. */
@@ -964,6 +943,8 @@ static void lossless_matrix_coeffs(MLPEn
 {
     DecodingParams *dp = ctx->cur_decoding_params;
     MatrixParams *mp = &dp->matrix_params;
+    unsigned int shift = 0;
+    unsigned int channel;
     int mode, mat;
 
     /* No decorrelation for mono. */
@@ -1001,42 +982,25 @@ static void lossless_matrix_coeffs(MLPEn
         case MLP_CHMODE_MID_SIDE:
             mp->count    = 2;
             mp->outch[0] = 0;
-            mp->coeff[0][0] =  1 << 13; mp->coeff[0][1] =  1 << 14;
+            mp->coeff[0][0] =  1 << 12; mp->coeff[0][1] =  1 << 13;
             mp->coeff[0][2] =  0 << 14; mp->coeff[0][2] =  0 << 14;
             mp->forco[0][0] =  1 << 14; mp->forco[0][1] = -1 << 14;
             mp->forco[0][2] =  0 << 14; mp->forco[0][2] =  0 << 14;
             mp->outch[1] = 1;
-            mp->coeff[1][0] = -1 << 14; mp->coeff[1][1] =  1 << 15;
+            mp->coeff[1][0] = -1 << 14; mp->coeff[1][1] =  1 << 14;
             mp->coeff[1][2] =  0 << 14; mp->coeff[1][2] =  0 << 14;
             mp->forco[1][0] =  1 << 13; mp->forco[1][1] =  1 << 14;
             mp->forco[1][2] =  0 << 14; mp->forco[1][2] =  0 << 14;
+            shift = 1;
             break;
 #endif
     }
 
     for (mat = 0; mat < mp->count; mat++)
         code_matrix_coeffs(ctx, mat);
-}
-
-/** Applies output_shift to all channels when it is needed because of shifted
- *  matrix coefficients.
- */
-static void output_shift_channels(MLPEncodeContext *ctx)
-{
-    DecodingParams *dp = ctx->cur_decoding_params;
-    MatrixParams *mp = &dp->matrix_params;
-    int32_t *sample_buffer = ctx->sample_buffer;
-    unsigned int i;
-
-    for (i = 0; i < ctx->major_frame_size; i++) {
-        unsigned int channel;
-
-        for (channel = 0; channel < ctx->num_channels - 2; channel++) {
-            *sample_buffer++ >>= mp->shift[channel];
-        }
 
-        sample_buffer += 2;
-    }
+    for (channel = 0; channel < ctx->num_channels; channel++)
+        mp->shift[channel] = shift;
 }
 
 /** Rematrixes all channels using chosen coefficients. */
@@ -1670,6 +1634,7 @@ static void copy_restart_frame_params(ML
             unsigned int filter;
 
             dp->quant_step_size[channel] = ctx->cur_decoding_params->quant_step_size[channel];
+            dp->matrix_params.shift[channel] = ctx->cur_decoding_params->matrix_params.shift[channel];
 
             if (index)
                 for (filter = 0; filter < NUM_FILTERS; filter++)
@@ -1748,7 +1713,6 @@ static int mlp_encode_frame(AVCodecConte
             ctx->cur_channel_params = ctx->channel_params[ctx->frame_index][1];
 
             lossless_matrix_coeffs   (ctx);
-            output_shift_channels    (ctx);
             rematrix_channels        (ctx);
             determine_quant_step_size(ctx);
             determine_filters        (ctx);