1 /*****************************************************************************
2 * lookahead.c: high-level lookahead functions
3 *****************************************************************************
4 * Copyright (C) 2010-2015 Avail Media and x264 project
6 * Authors: Michael Kazmier <mkazmier@availmedia.com>
7 * Alex Giladi <agiladi@availmedia.com>
8 * Steven Walters <kemuri9@gmail.com>
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.
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.
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.
24 * This program is also available under a commercial proprietary license.
25 * For more information, contact us at licensing@x264.com.
26 *****************************************************************************/
28 /* LOOKAHEAD (threaded and non-threaded mode)
31 * [1] Slice type / scene cut;
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.
39 #include "common/common.h"
42 static void x264_lookahead_shift( x264_sync_frame_list_t *dst, x264_sync_frame_list_t *src, int count )
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 );
54 x264_pthread_cond_broadcast( &dst->cv_fill );
55 x264_pthread_cond_broadcast( &src->cv_empty );
59 static void x264_lookahead_update_last_nonb( x264_t *h, x264_frame_t *new_nonb )
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++;
68 static void x264_lookahead_slicetype_decide( x264_t *h )
70 x264_stack_align( x264_slicetype_decide, h );
72 x264_lookahead_update_last_nonb( h, h->lookahead->next.list[0] );
73 int shift_frames = h->lookahead->next.list[0]->i_bframes + 1;
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 );
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 );
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 );
87 x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
90 static void *x264_lookahead_thread( x264_t *h )
92 while( !h->lookahead->b_exit_thread )
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 )
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 );
107 x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
108 x264_lookahead_slicetype_decide( h );
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 );
126 int x264_lookahead_init( x264_t *h, int i_slicetype_length )
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;
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;
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 ) )
144 if( !h->param.i_sync_lookahead )
147 x264_t *look_h = h->thread[h->param.i_threads];
149 if( x264_macroblock_cache_allocate( look_h ) )
152 if( x264_macroblock_thread_allocate( look_h, 1 ) < 0 )
155 if( x264_pthread_create( &look->thread_handle, NULL, (void*)x264_lookahead_thread, look_h ) )
157 look->b_thread_active = 1;
165 void x264_lookahead_delete( x264_t *h )
167 if( h->param.i_sync_lookahead )
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] );
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 );
186 void x264_lookahead_put_frame( x264_t *h, x264_frame_t *frame )
188 if( h->param.i_sync_lookahead )
189 x264_sync_frame_list_push( &h->lookahead->ifbuf, frame );
191 x264_sync_frame_list_push( &h->lookahead->next, frame );
194 int x264_lookahead_is_empty( x264_t *h )
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 );
204 static void x264_lookahead_encoder_shift( x264_t *h )
206 if( !h->lookahead->ofbuf.i_size )
208 int i_frames = h->lookahead->ofbuf.list[0]->i_bframes + 1;
211 x264_frame_push( h->frames.current, x264_frame_shift( h->lookahead->ofbuf.list ) );
212 h->lookahead->ofbuf.i_size--;
214 x264_pthread_cond_broadcast( &h->lookahead->ofbuf.cv_empty );
217 void x264_lookahead_get_frames( x264_t *h )
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 );
228 { /* We are not running a lookahead thread, so perform all the slicetype decide on the fly */
230 if( h->frames.current[0] || !h->lookahead->next.i_size )
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 );
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 );
242 x264_lookahead_encoder_shift( h );