git.sesse.net Git - x264/blob - encoder/lookahead.c

   1 /*****************************************************************************
   2  * lookahead.c: high-level lookahead functions
   3  *****************************************************************************
   4  * Copyright (C) 2010-2015 Avail Media and x264 project
   5  *
   6  * Authors: Michael Kazmier <mkazmier@availmedia.com>
   7  *          Alex Giladi <agiladi@availmedia.com>
   8  *          Steven Walters <kemuri9@gmail.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02111, USA.
  23  *
  24  * This program is also available under a commercial proprietary license.
  25  * For more information, contact us at licensing@x264.com.
  26  *****************************************************************************/
  27
  28 /* LOOKAHEAD (threaded and non-threaded mode)
  29  *
  30  * Lookahead types:
  31  *     [1] Slice type / scene cut;
  32  *
  33  * In non-threaded mode, we run the existing slicetype decision code as it was.
  34  * In threaded mode, we run in a separate thread, that lives between the calls
  35  * to x264_encoder_open() and x264_encoder_close(), and performs lookahead for
  36  * the number of frames specified in rc_lookahead.  Recommended setting is
  37  * # of bframes + # of threads.
  38  */
  39 #include "common/common.h"
  40 #include "analyse.h"
  41
  42 static void x264_lookahead_shift( x264_sync_frame_list_t *dst, x264_sync_frame_list_t *src, int count )
  43 {
  44     int i = count;
  45     while( i-- )
  46     {
  47         assert( dst->i_size < dst->i_max_size );
  48         assert( src->i_size );
  49         dst->list[ dst->i_size++ ] = x264_frame_shift( src->list );
  50         src->i_size--;
  51     }
  52     if( count )
  53     {
  54         x264_pthread_cond_broadcast( &dst->cv_fill );
  55         x264_pthread_cond_broadcast( &src->cv_empty );
  56     }
  57 }
  58
  59 static void x264_lookahead_update_last_nonb( x264_t *h, x264_frame_t *new_nonb )
  60 {
  61     if( h->lookahead->last_nonb )
  62         x264_frame_push_unused( h, h->lookahead->last_nonb );
  63     h->lookahead->last_nonb = new_nonb;
  64     new_nonb->i_reference_count++;
  65 }
  66
  67 #if HAVE_THREAD
  68 static void x264_lookahead_slicetype_decide( x264_t *h )
  69 {
  70     x264_stack_align( x264_slicetype_decide, h );
  71
  72     x264_lookahead_update_last_nonb( h, h->lookahead->next.list[0] );
  73     int shift_frames = h->lookahead->next.list[0]->i_bframes + 1;
  74
  75     x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
  76     while( h->lookahead->ofbuf.i_size == h->lookahead->ofbuf.i_max_size )
  77         x264_pthread_cond_wait( &h->lookahead->ofbuf.cv_empty, &h->lookahead->ofbuf.mutex );
  78
  79     x264_pthread_mutex_lock( &h->lookahead->next.mutex );
  80     x264_lookahead_shift( &h->lookahead->ofbuf, &h->lookahead->next, shift_frames );
  81     x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
  82
  83     /* For MB-tree and VBV lookahead, we have to perform propagation analysis on I-frames too. */
  84     if( h->lookahead->b_analyse_keyframe && IS_X264_TYPE_I( h->lookahead->last_nonb->i_type ) )
  85         x264_stack_align( x264_slicetype_analyse, h, shift_frames );
  86
  87     x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
  88 }
  89
  90 static void *x264_lookahead_thread( x264_t *h )
  91 {
  92     while( !h->lookahead->b_exit_thread )
  93     {
  94         x264_pthread_mutex_lock( &h->lookahead->ifbuf.mutex );
  95         x264_pthread_mutex_lock( &h->lookahead->next.mutex );
  96         int shift = X264_MIN( h->lookahead->next.i_max_size - h->lookahead->next.i_size, h->lookahead->ifbuf.i_size );
  97         x264_lookahead_shift( &h->lookahead->next, &h->lookahead->ifbuf, shift );
  98         x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
  99         if( h->lookahead->next.i_size <= h->lookahead->i_slicetype_length + h->param.b_vfr_input )
 100         {
 101             while( !h->lookahead->ifbuf.i_size && !h->lookahead->b_exit_thread )
 102                 x264_pthread_cond_wait( &h->lookahead->ifbuf.cv_fill, &h->lookahead->ifbuf.mutex );
 103             x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
 104         }
 105         else
 106         {
 107             x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
 108             x264_lookahead_slicetype_decide( h );
 109         }
 110     }   /* end of input frames */
 111     x264_pthread_mutex_lock( &h->lookahead->ifbuf.mutex );
 112     x264_pthread_mutex_lock( &h->lookahead->next.mutex );
 113     x264_lookahead_shift( &h->lookahead->next, &h->lookahead->ifbuf, h->lookahead->ifbuf.i_size );
 114     x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
 115     x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
 116     while( h->lookahead->next.i_size )
 117         x264_lookahead_slicetype_decide( h );
 118     x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
 119     h->lookahead->b_thread_active = 0;
 120     x264_pthread_cond_broadcast( &h->lookahead->ofbuf.cv_fill );
 121     x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
 122     return NULL;
 123 }
 124 #endif
 125
 126 int x264_lookahead_init( x264_t *h, int i_slicetype_length )
 127 {
 128     x264_lookahead_t *look;
 129     CHECKED_MALLOCZERO( look, sizeof(x264_lookahead_t) );
 130     for( int i = 0; i < h->param.i_threads; i++ )
 131         h->thread[i]->lookahead = look;
 132
 133     look->i_last_keyframe = - h->param.i_keyint_max;
 134     look->b_analyse_keyframe = (h->param.rc.b_mb_tree || (h->param.rc.i_vbv_buffer_size && h->param.rc.i_lookahead))
 135                                && !h->param.rc.b_stat_read;
 136     look->i_slicetype_length = i_slicetype_length;
 137
 138     /* init frame lists */
 139     if( x264_sync_frame_list_init( &look->ifbuf, h->param.i_sync_lookahead+3 ) ||
 140         x264_sync_frame_list_init( &look->next, h->frames.i_delay+3 ) ||
 141         x264_sync_frame_list_init( &look->ofbuf, h->frames.i_delay+3 ) )
 142         goto fail;
 143
 144     if( !h->param.i_sync_lookahead )
 145         return 0;
 146
 147     x264_t *look_h = h->thread[h->param.i_threads];
 148     *look_h = *h;
 149     if( x264_macroblock_cache_allocate( look_h ) )
 150         goto fail;
 151
 152     if( x264_macroblock_thread_allocate( look_h, 1 ) < 0 )
 153         goto fail;
 154
 155     if( x264_pthread_create( &look->thread_handle, NULL, (void*)x264_lookahead_thread, look_h ) )
 156         goto fail;
 157     look->b_thread_active = 1;
 158
 159     return 0;
 160 fail:
 161     x264_free( look );
 162     return -1;
 163 }
 164
 165 void x264_lookahead_delete( x264_t *h )
 166 {
 167     if( h->param.i_sync_lookahead )
 168     {
 169         x264_pthread_mutex_lock( &h->lookahead->ifbuf.mutex );
 170         h->lookahead->b_exit_thread = 1;
 171         x264_pthread_cond_broadcast( &h->lookahead->ifbuf.cv_fill );
 172         x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
 173         x264_pthread_join( h->lookahead->thread_handle, NULL );
 174         x264_macroblock_cache_free( h->thread[h->param.i_threads] );
 175         x264_macroblock_thread_free( h->thread[h->param.i_threads], 1 );
 176         x264_free( h->thread[h->param.i_threads] );
 177     }
 178     x264_sync_frame_list_delete( &h->lookahead->ifbuf );
 179     x264_sync_frame_list_delete( &h->lookahead->next );
 180     if( h->lookahead->last_nonb )
 181         x264_frame_push_unused( h, h->lookahead->last_nonb );
 182     x264_sync_frame_list_delete( &h->lookahead->ofbuf );
 183     x264_free( h->lookahead );
 184 }
 185
 186 void x264_lookahead_put_frame( x264_t *h, x264_frame_t *frame )
 187 {
 188     if( h->param.i_sync_lookahead )
 189         x264_sync_frame_list_push( &h->lookahead->ifbuf, frame );
 190     else
 191         x264_sync_frame_list_push( &h->lookahead->next, frame );
 192 }
 193
 194 int x264_lookahead_is_empty( x264_t *h )
 195 {
 196     x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
 197     x264_pthread_mutex_lock( &h->lookahead->next.mutex );
 198     int b_empty = !h->lookahead->next.i_size && !h->lookahead->ofbuf.i_size;
 199     x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
 200     x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
 201     return b_empty;
 202 }
 203
 204 static void x264_lookahead_encoder_shift( x264_t *h )
 205 {
 206     if( !h->lookahead->ofbuf.i_size )
 207         return;
 208     int i_frames = h->lookahead->ofbuf.list[0]->i_bframes + 1;
 209     while( i_frames-- )
 210     {
 211         x264_frame_push( h->frames.current, x264_frame_shift( h->lookahead->ofbuf.list ) );
 212         h->lookahead->ofbuf.i_size--;
 213     }
 214     x264_pthread_cond_broadcast( &h->lookahead->ofbuf.cv_empty );
 215 }
 216
 217 void x264_lookahead_get_frames( x264_t *h )
 218 {
 219     if( h->param.i_sync_lookahead )
 220     {   /* We have a lookahead thread, so get frames from there */
 221         x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
 222         while( !h->lookahead->ofbuf.i_size && h->lookahead->b_thread_active )
 223             x264_pthread_cond_wait( &h->lookahead->ofbuf.cv_fill, &h->lookahead->ofbuf.mutex );
 224         x264_lookahead_encoder_shift( h );
 225         x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
 226     }
 227     else
 228     {   /* We are not running a lookahead thread, so perform all the slicetype decide on the fly */
 229
 230         if( h->frames.current[0] || !h->lookahead->next.i_size )
 231             return;
 232
 233         x264_stack_align( x264_slicetype_decide, h );
 234         x264_lookahead_update_last_nonb( h, h->lookahead->next.list[0] );
 235         int shift_frames = h->lookahead->next.list[0]->i_bframes + 1;
 236         x264_lookahead_shift( &h->lookahead->ofbuf, &h->lookahead->next, shift_frames );
 237
 238         /* For MB-tree and VBV lookahead, we have to perform propagation analysis on I-frames too. */
 239         if( h->lookahead->b_analyse_keyframe && IS_X264_TYPE_I( h->lookahead->last_nonb->i_type ) )
 240             x264_stack_align( x264_slicetype_analyse, h, shift_frames );
 241
 242         x264_lookahead_encoder_shift( h );
 243     }
 244 }