]> git.sesse.net Git - x264/blobdiff - encoder/ratecontrol.c
Fix high bit depth lookahead cost compensation algorithm
[x264] / encoder / ratecontrol.c
index 86aad96b5fbc635339e82a234bdb7559e8ad0a2c..8b8e76e643c35370f802620d436307b7b990b590 100644 (file)
@@ -1,7 +1,7 @@
 /*****************************************************************************
  * ratecontrol.c: ratecontrol
  *****************************************************************************
- * Copyright (C) 2005-2014 x264 project
+ * Copyright (C) 2005-2015 x264 project
  *
  * Authors: Loren Merritt <lorenm@u.washington.edu>
  *          Michael Niedermayer <michaelni@gmx.at>
@@ -96,6 +96,7 @@ struct x264_ratecontrol_t
     /* VBV stuff */
     double buffer_size;
     int64_t buffer_fill_final;
+    int64_t buffer_fill_final_min;
     double buffer_fill;         /* planned buffer, if all in-progress frames hit their bit budget */
     double buffer_rate;         /* # of bits added to buffer_fill after each frame */
     double vbv_max_rate;        /* # of bits added to buffer_fill per second */
@@ -200,11 +201,11 @@ static void update_predictor( predictor_t *p, float q, float var, float bits );
  */
 static inline float qp2qscale( float qp )
 {
-    return 0.85f * powf( 2.0f, ( qp - 12.0f ) / 6.0f );
+    return 0.85f * powf( 2.0f, ( qp - (12.0f + QP_BD_OFFSET) ) / 6.0f );
 }
 static inline float qscale2qp( float qscale )
 {
-    return 12.0f + 6.0f * log2f( qscale/0.85f );
+    return (12.0f + QP_BD_OFFSET) + 6.0f * log2f( qscale/0.85f );
 }
 
 /* Texture bitrate is not quite inversely proportional to qscale,
@@ -301,10 +302,6 @@ static NOINLINE uint32_t x264_ac_energy_mb( x264_t *h, int mb_x, int mb_y, x264_
 
 void x264_adaptive_quant_frame( x264_t *h, x264_frame_t *frame, float *quant_offsets )
 {
-    /* constants chosen to result in approximately the same overall bitrate as without AQ.
-     * FIXME: while they're written in 5 significant digits, they're only tuned to 2. */
-    float strength;
-    float avg_adj = 0.f;
     /* Initialize frame stats */
     for( int i = 0; i < 3; i++ )
     {
@@ -348,23 +345,30 @@ void x264_adaptive_quant_frame( x264_t *h, x264_frame_t *frame, float *quant_off
     /* Actual adaptive quantization */
     else
     {
-        if( h->param.rc.i_aq_mode == X264_AQ_AUTOVARIANCE )
+        /* constants chosen to result in approximately the same overall bitrate as without AQ.
+         * FIXME: while they're written in 5 significant digits, they're only tuned to 2. */
+        float strength;
+        float avg_adj = 0.f;
+        float bias_strength = 0.f;
+
+        if( h->param.rc.i_aq_mode == X264_AQ_AUTOVARIANCE || h->param.rc.i_aq_mode == X264_AQ_AUTOVARIANCE_BIASED )
         {
-            float bit_depth_correction = powf(1 << (BIT_DEPTH-8), 0.5f);
+            float bit_depth_correction = 1.f / (1 << (2*(BIT_DEPTH-8)));
             float avg_adj_pow2 = 0.f;
             for( int mb_y = 0; mb_y < h->mb.i_mb_height; mb_y++ )
                 for( int mb_x = 0; mb_x < h->mb.i_mb_width; mb_x++ )
                 {
                     uint32_t energy = x264_ac_energy_mb( h, mb_x, mb_y, frame );
-                    float qp_adj = powf( energy + 1, 0.125f );
+                    float qp_adj = powf( energy * bit_depth_correction + 1, 0.125f );
                     frame->f_qp_offset[mb_x + mb_y*h->mb.i_mb_stride] = qp_adj;
                     avg_adj += qp_adj;
                     avg_adj_pow2 += qp_adj * qp_adj;
                 }
             avg_adj /= h->mb.i_mb_count;
             avg_adj_pow2 /= h->mb.i_mb_count;
-            strength = h->param.rc.f_aq_strength * avg_adj / bit_depth_correction;
-            avg_adj = avg_adj - 0.5f * (avg_adj_pow2 - (14.f * bit_depth_correction)) / avg_adj;
+            strength = h->param.rc.f_aq_strength * avg_adj;
+            avg_adj = avg_adj - 0.5f * (avg_adj_pow2 - 14.f) / avg_adj;
+            bias_strength = h->param.rc.f_aq_strength;
         }
         else
             strength = h->param.rc.f_aq_strength * 1.0397f;
@@ -374,7 +378,12 @@ void x264_adaptive_quant_frame( x264_t *h, x264_frame_t *frame, float *quant_off
             {
                 float qp_adj;
                 int mb_xy = mb_x + mb_y*h->mb.i_mb_stride;
-                if( h->param.rc.i_aq_mode == X264_AQ_AUTOVARIANCE )
+                if( h->param.rc.i_aq_mode == X264_AQ_AUTOVARIANCE_BIASED )
+                {
+                    qp_adj = frame->f_qp_offset[mb_xy];
+                    qp_adj = strength * (qp_adj - avg_adj) + bias_strength * (1.f - 14.f / (qp_adj * qp_adj));
+                }
+                else if( h->param.rc.i_aq_mode == X264_AQ_AUTOVARIANCE )
                 {
                     qp_adj = frame->f_qp_offset[mb_xy];
                     qp_adj = strength * (qp_adj - avg_adj);
@@ -724,7 +733,8 @@ void x264_ratecontrol_init_reconfigurable( x264_t *h, int b_init )
             if( h->param.rc.f_vbv_buffer_init > 1. )
                 h->param.rc.f_vbv_buffer_init = x264_clip3f( h->param.rc.f_vbv_buffer_init / h->param.rc.i_vbv_buffer_size, 0, 1 );
             h->param.rc.f_vbv_buffer_init = x264_clip3f( X264_MAX( h->param.rc.f_vbv_buffer_init, rc->buffer_rate / rc->buffer_size ), 0, 1);
-            rc->buffer_fill_final = rc->buffer_size * h->param.rc.f_vbv_buffer_init * h->sps->vui.i_time_scale;
+            rc->buffer_fill_final =
+            rc->buffer_fill_final_min = rc->buffer_size * h->param.rc.f_vbv_buffer_init * h->sps->vui.i_time_scale;
             rc->b_vbv = 1;
             rc->b_vbv_min_rate = !rc->b_2pass
                           && h->param.rc.i_rc_method == X264_RC_ABR
@@ -776,11 +786,11 @@ int x264_ratecontrol_new( x264_t *h )
     if( h->param.i_nal_hrd )
     {
         uint64_t denom = (uint64_t)h->sps->vui.hrd.i_bit_rate_unscaled * h->sps->vui.i_time_scale;
-        uint64_t num = 180000;
+        uint64_t num = 90000;
         x264_reduce_fraction64( &num, &denom );
-        rc->hrd_multiply_denom = 180000 / num;
+        rc->hrd_multiply_denom = 90000 / num;
 
-        double bits_required = log2( 180000 / rc->hrd_multiply_denom )
+        double bits_required = log2( 90000 / rc->hrd_multiply_denom )
                              + log2( h->sps->vui.i_time_scale )
                              + log2( h->sps->vui.hrd.i_cpb_size_unscaled );
         if( bits_required >= 63 )
@@ -818,10 +828,11 @@ int x264_ratecontrol_new( x264_t *h )
     h->mb.ip_offset = rc->ip_offset + 0.5;
 
     rc->lstep = pow( 2, h->param.rc.i_qp_step / 6.0 );
-    rc->last_qscale = qp2qscale( 26 );
+    rc->last_qscale = qp2qscale( 26 + QP_BD_OFFSET );
     int num_preds = h->param.b_sliced_threads * h->param.i_threads + 1;
     CHECKED_MALLOC( rc->pred, 5 * sizeof(predictor_t) * num_preds );
     CHECKED_MALLOC( rc->pred_b_from_p, sizeof(predictor_t) );
+    static const float pred_coeff_table[3] = { 1.0, 1.0, 1.5 };
     for( int i = 0; i < 3; i++ )
     {
         rc->last_qscale_for[i] = qp2qscale( ABR_INIT_QP );
@@ -829,8 +840,8 @@ int x264_ratecontrol_new( x264_t *h )
         rc->lmax[i] = qp2qscale( h->param.rc.i_qp_max );
         for( int j = 0; j < num_preds; j++ )
         {
-            rc->pred[i+j*5].coeff_min = 2.0 / 4;
-            rc->pred[i+j*5].coeff = 2.0;
+            rc->pred[i+j*5].coeff_min = pred_coeff_table[i] / 2;
+            rc->pred[i+j*5].coeff = pred_coeff_table[i];
             rc->pred[i+j*5].count = 1.0;
             rc->pred[i+j*5].decay = 0.5;
             rc->pred[i+j*5].offset = 0.0;
@@ -844,7 +855,11 @@ int x264_ratecontrol_new( x264_t *h )
             rc->row_preds[i][j].offset = 0.0;
         }
     }
-    *rc->pred_b_from_p = rc->pred[0];
+    rc->pred_b_from_p->coeff_min = 0.5 / 2;
+    rc->pred_b_from_p->coeff = 0.5;
+    rc->pred_b_from_p->count = 1.0;
+    rc->pred_b_from_p->decay = 0.5;
+    rc->pred_b_from_p->offset = 0.0;
 
     if( parse_zones( h ) < 0 )
     {
@@ -1009,7 +1024,7 @@ int x264_ratecontrol_new( x264_t *h )
         {
             ratecontrol_entry_t *rce = &rc->entry[i];
             rce->pict_type = SLICE_TYPE_P;
-            rce->qscale = rce->new_qscale = qp2qscale( 20 );
+            rce->qscale = rce->new_qscale = qp2qscale( 20 + QP_BD_OFFSET );
             rce->misc_bits = rc->nmb + 10;
             rce->new_qp = 0;
         }
@@ -1571,7 +1586,7 @@ int x264_ratecontrol_mb( x264_t *h, int bits )
     h->fdec->f_row_qscale[y] = qscale;
 
     update_predictor( &rc->row_pred[0], qscale, h->fdec->i_row_satd[y], h->fdec->i_row_bits[y] );
-    if( h->sh.i_type == SLICE_TYPE_P && rc->qpm < h->fref[0][0]->f_row_qp[y] )
+    if( h->sh.i_type != SLICE_TYPE_I && rc->qpm < h->fref[0][0]->f_row_qp[y] )
         update_predictor( &rc->row_pred[1], qscale, h->fdec->i_row_satds[0][0][y], h->fdec->i_row_bits[y] );
 
     /* update ratecontrol per-mbpair in MBAFF */
@@ -1914,15 +1929,16 @@ int x264_ratecontrol_end( x264_t *h, int bits, int *filler )
             h->fenc->hrd_timing.cpb_removal_time = rc->nrt_first_access_unit + (double)(h->fenc->i_cpb_delay - h->i_cpb_delay_pir_offset) *
                                                    h->sps->vui.i_num_units_in_tick / h->sps->vui.i_time_scale;
 
-            double cpb_earliest_arrival_time = h->fenc->hrd_timing.cpb_removal_time - (double)rc->initial_cpb_removal_delay / 90000;
             if( h->fenc->b_keyframe )
             {
-                 rc->nrt_first_access_unit = h->fenc->hrd_timing.cpb_removal_time;
-                 rc->initial_cpb_removal_delay = h->initial_cpb_removal_delay;
-                 rc->initial_cpb_removal_delay_offset = h->initial_cpb_removal_delay_offset;
+                rc->nrt_first_access_unit = h->fenc->hrd_timing.cpb_removal_time;
+                rc->initial_cpb_removal_delay = h->initial_cpb_removal_delay;
+                rc->initial_cpb_removal_delay_offset = h->initial_cpb_removal_delay_offset;
             }
-            else
-                 cpb_earliest_arrival_time -= (double)rc->initial_cpb_removal_delay_offset / 90000;
+
+            double cpb_earliest_arrival_time = h->fenc->hrd_timing.cpb_removal_time - (double)rc->initial_cpb_removal_delay / 90000;
+            if( !h->fenc->b_keyframe )
+                cpb_earliest_arrival_time -= (double)rc->initial_cpb_removal_delay_offset / 90000;
 
             if( h->sps->vui.hrd.b_cbr_hrd )
                 h->fenc->hrd_timing.cpb_initial_arrival_time = rc->previous_cpb_final_arrival_time;
@@ -2073,7 +2089,8 @@ static void update_predictor( predictor_t *p, float q, float var, float bits )
     if( var < 10 )
         return;
     float old_coeff = p->coeff / p->count;
-    float new_coeff = X264_MAX( bits*q / var, p->coeff_min );
+    float old_offset = p->offset / p->count;
+    float new_coeff = X264_MAX( (bits*q - old_offset) / var, p->coeff_min );
     float new_coeff_clipped = x264_clip3f( new_coeff, old_coeff/range, old_coeff*range );
     float new_offset = bits*q - new_coeff_clipped * var;
     if( new_offset >= 0 )
@@ -2095,7 +2112,7 @@ static int update_vbv( x264_t *h, int bits )
     int bitrate = h->sps->vui.hrd.i_bit_rate_unscaled;
     x264_ratecontrol_t *rcc = h->rc;
     x264_ratecontrol_t *rct = h->thread[0]->rc;
-    uint64_t buffer_size = (uint64_t)h->sps->vui.hrd.i_cpb_size_unscaled * h->sps->vui.i_time_scale;
+    int64_t buffer_size = (int64_t)h->sps->vui.hrd.i_cpb_size_unscaled * h->sps->vui.i_time_scale;
 
     if( rcc->last_satd >= h->mb.i_mb_count )
         update_predictor( &rct->pred[h->sh.i_type], qp2qscale( rcc->qpa_rc ), rcc->last_satd, bits );
@@ -2103,32 +2120,45 @@ static int update_vbv( x264_t *h, int bits )
     if( !rcc->b_vbv )
         return filler;
 
-    rct->buffer_fill_final -= (uint64_t)bits * h->sps->vui.i_time_scale;
+    uint64_t buffer_diff = (uint64_t)bits * h->sps->vui.i_time_scale;
+    rct->buffer_fill_final -= buffer_diff;
+    rct->buffer_fill_final_min -= buffer_diff;
 
-    if( rct->buffer_fill_final < 0 )
+    if( rct->buffer_fill_final_min < 0 )
     {
-        double underflow = (double)rct->buffer_fill_final / h->sps->vui.i_time_scale;
+        double underflow = (double)rct->buffer_fill_final_min / h->sps->vui.i_time_scale;
         if( rcc->rate_factor_max_increment && rcc->qpm >= rcc->qp_novbv + rcc->rate_factor_max_increment )
             x264_log( h, X264_LOG_DEBUG, "VBV underflow due to CRF-max (frame %d, %.0f bits)\n", h->i_frame, underflow );
         else
             x264_log( h, X264_LOG_WARNING, "VBV underflow (frame %d, %.0f bits)\n", h->i_frame, underflow );
+        rct->buffer_fill_final =
+        rct->buffer_fill_final_min = 0;
     }
-    rct->buffer_fill_final = X264_MAX( rct->buffer_fill_final, 0 );
 
     if( h->param.i_avcintra_class )
-        rct->buffer_fill_final += buffer_size;
+        buffer_diff = buffer_size;
     else
-        rct->buffer_fill_final += (uint64_t)bitrate * h->sps->vui.i_num_units_in_tick * h->fenc->i_cpb_duration;
+        buffer_diff = (uint64_t)bitrate * h->sps->vui.i_num_units_in_tick * h->fenc->i_cpb_duration;
+    rct->buffer_fill_final += buffer_diff;
+    rct->buffer_fill_final_min += buffer_diff;
 
-    if( h->param.rc.b_filler && rct->buffer_fill_final > buffer_size )
+    if( rct->buffer_fill_final > buffer_size )
     {
-        int64_t scale = (int64_t)h->sps->vui.i_time_scale * 8;
-        filler = (rct->buffer_fill_final - buffer_size + scale - 1) / scale;
-        bits = h->param.i_avcintra_class ? filler * 8 : X264_MAX( (FILLER_OVERHEAD - h->param.b_annexb), filler ) * 8;
-        rct->buffer_fill_final -= (uint64_t)bits * h->sps->vui.i_time_scale;
+        if( h->param.rc.b_filler )
+        {
+            int64_t scale = (int64_t)h->sps->vui.i_time_scale * 8;
+            filler = (rct->buffer_fill_final - buffer_size + scale - 1) / scale;
+            bits = h->param.i_avcintra_class ? filler * 8 : X264_MAX( (FILLER_OVERHEAD - h->param.b_annexb), filler ) * 8;
+            buffer_diff = (uint64_t)bits * h->sps->vui.i_time_scale;
+            rct->buffer_fill_final -= buffer_diff;
+            rct->buffer_fill_final_min -= buffer_diff;
+        }
+        else
+        {
+            rct->buffer_fill_final = X264_MIN( rct->buffer_fill_final, buffer_size );
+            rct->buffer_fill_final_min = X264_MIN( rct->buffer_fill_final_min, buffer_size );
+        }
     }
-    else
-        rct->buffer_fill_final = X264_MIN( rct->buffer_fill_final, buffer_size );
 
     return filler;
 }
@@ -2139,23 +2169,27 @@ void x264_hrd_fullness( x264_t *h )
     uint64_t denom = (uint64_t)h->sps->vui.hrd.i_bit_rate_unscaled * h->sps->vui.i_time_scale / rct->hrd_multiply_denom;
     uint64_t cpb_state = rct->buffer_fill_final;
     uint64_t cpb_size = (uint64_t)h->sps->vui.hrd.i_cpb_size_unscaled * h->sps->vui.i_time_scale;
-    uint64_t multiply_factor = 180000 / rct->hrd_multiply_denom;
+    uint64_t multiply_factor = 90000 / rct->hrd_multiply_denom;
 
-    if( rct->buffer_fill_final < 0 || rct->buffer_fill_final > cpb_size )
+    if( rct->buffer_fill_final < 0 || rct->buffer_fill_final > (int64_t)cpb_size )
     {
-         x264_log( h, X264_LOG_WARNING, "CPB %s: %.0lf bits in a %.0lf-bit buffer\n",
-                   rct->buffer_fill_final < 0 ? "underflow" : "overflow", (float)rct->buffer_fill_final/denom, (float)cpb_size/denom );
+         x264_log( h, X264_LOG_WARNING, "CPB %s: %.0f bits in a %.0f-bit buffer\n",
+                   rct->buffer_fill_final < 0 ? "underflow" : "overflow",
+                   (double)rct->buffer_fill_final / h->sps->vui.i_time_scale, (double)cpb_size / h->sps->vui.i_time_scale );
     }
 
-    h->initial_cpb_removal_delay = (multiply_factor * cpb_state + denom) / (2*denom);
-    h->initial_cpb_removal_delay_offset = (multiply_factor * cpb_size + denom) / (2*denom) - h->initial_cpb_removal_delay;
+    h->initial_cpb_removal_delay = (multiply_factor * cpb_state) / denom;
+    h->initial_cpb_removal_delay_offset = (multiply_factor * cpb_size) / denom - h->initial_cpb_removal_delay;
+
+    int64_t decoder_buffer_fill = h->initial_cpb_removal_delay * denom / multiply_factor;
+    rct->buffer_fill_final_min = X264_MIN( rct->buffer_fill_final_min, decoder_buffer_fill );
 }
 
 // provisionally update VBV according to the planned size of all frames currently in progress
 static void update_vbv_plan( x264_t *h, int overhead )
 {
     x264_ratecontrol_t *rcc = h->rc;
-    rcc->buffer_fill = h->thread[0]->rc->buffer_fill_final / h->sps->vui.i_time_scale;
+    rcc->buffer_fill = h->thread[0]->rc->buffer_fill_final_min / h->sps->vui.i_time_scale;
     if( h->i_thread_frames > 1 )
     {
         int j = h->rc - h->thread[0]->rc;
@@ -2335,7 +2369,7 @@ static float rate_estimate_qscale( x264_t *h )
 {
     float q;
     x264_ratecontrol_t *rcc = h->rc;
-    ratecontrol_entry_t UNINIT(rce);
+    ratecontrol_entry_t rce = {0};
     int pict_type = h->sh.i_type;
     int64_t total_bits = 8*(h->stat.i_frame_size[SLICE_TYPE_I]
                           + h->stat.i_frame_size[SLICE_TYPE_P]