1 /*****************************************************************************
2 * lookahead.c: high-level lookahead functions
3 *****************************************************************************
4 * Copyright (C) 2010-2014 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
x264_lookahead_shift(x264_sync_frame_list_t * dst,x264_sync_frame_list_t * src,int count)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
x264_lookahead_update_last_nonb(x264_t * h,x264_frame_t * new_nonb)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
x264_lookahead_slicetype_decide(x264_t * h)68 static void x264_lookahead_slicetype_decide( x264_t *h )
69 {
70 int shift_frames;
71
72 x264_stack_align( x264_slicetype_decide, h );
73
74 x264_lookahead_update_last_nonb( h, h->lookahead->next.list[0] );
75 shift_frames = h->lookahead->next.list[0]->i_bframes + 1;
76
77 x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
78 while( h->lookahead->ofbuf.i_size == h->lookahead->ofbuf.i_max_size )
79 x264_pthread_cond_wait( &h->lookahead->ofbuf.cv_empty, &h->lookahead->ofbuf.mutex );
80
81 x264_pthread_mutex_lock( &h->lookahead->next.mutex );
82 x264_lookahead_shift( &h->lookahead->ofbuf, &h->lookahead->next, shift_frames );
83 x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
84
85 /* For MB-tree and VBV lookahead, we have to perform propagation analysis on I-frames too. */
86 if( h->lookahead->b_analyse_keyframe && IS_X264_TYPE_I( h->lookahead->last_nonb->i_type ) )
87 x264_stack_align( x264_slicetype_analyse, h, shift_frames );
88 x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
89 }
90
x264_lookahead_thread(x264_t * h)91 static void *x264_lookahead_thread( x264_t *h )
92 {
93 while( !h->lookahead->b_exit_thread )
94 {
95 int shift;
96
97 x264_pthread_mutex_lock( &h->lookahead->ifbuf.mutex );
98 x264_pthread_mutex_lock( &h->lookahead->next.mutex );
99 shift = X264_MIN( h->lookahead->next.i_max_size - h->lookahead->next.i_size, h->lookahead->ifbuf.i_size );
100 x264_lookahead_shift( &h->lookahead->next, &h->lookahead->ifbuf, shift );
101 x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
102 if( h->lookahead->next.i_size <= h->lookahead->i_slicetype_length + h->param.b_vfr_input )
103 {
104 while( !h->lookahead->ifbuf.i_size && !h->lookahead->b_exit_thread )
105 x264_pthread_cond_wait( &h->lookahead->ifbuf.cv_fill, &h->lookahead->ifbuf.mutex );
106 x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
107 }
108 else
109 {
110 x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
111 x264_lookahead_slicetype_decide( h );
112 }
113 } /* end of input frames */
114 x264_pthread_mutex_lock( &h->lookahead->ifbuf.mutex );
115 x264_pthread_mutex_lock( &h->lookahead->next.mutex );
116 x264_lookahead_shift( &h->lookahead->next, &h->lookahead->ifbuf, h->lookahead->ifbuf.i_size );
117 x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
118 x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
119 while( h->lookahead->next.i_size )
120 x264_lookahead_slicetype_decide( h );
121 x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
122 h->lookahead->b_thread_active = 0;
123 x264_pthread_cond_broadcast( &h->lookahead->ofbuf.cv_fill );
124 x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
125 return NULL;
126 }
127 #endif
128
x264_lookahead_init(x264_t * h,int i_slicetype_length)129 int x264_lookahead_init( x264_t *h, int i_slicetype_length )
130 {
131 x264_lookahead_t *look;
132 int i;
133 x264_t *look_h;
134
135 CHECKED_MALLOCZERO( look, sizeof(x264_lookahead_t) );
136 for( i = 0; i < h->param.i_threads; i++ )
137 h->thread[i]->lookahead = look;
138
139 look->i_last_keyframe = - h->param.i_keyint_max;
140 look->b_analyse_keyframe = (h->param.rc.b_mb_tree || (h->param.rc.i_vbv_buffer_size && h->param.rc.i_lookahead))
141 && !h->param.rc.b_stat_read;
142 look->i_slicetype_length = i_slicetype_length;
143
144 /* init frame lists */
145 if( x264_sync_frame_list_init( &look->ifbuf, h->param.i_sync_lookahead+3 ) ||
146 x264_sync_frame_list_init( &look->next, h->frames.i_delay+3 ) ||
147 x264_sync_frame_list_init( &look->ofbuf, h->frames.i_delay+3 ) )
148 goto fail;
149
150 if( !h->param.i_sync_lookahead )
151 return 0;
152
153 look_h = h->thread[h->param.i_threads];
154 *look_h = *h;
155 if( x264_macroblock_cache_allocate( look_h ) )
156 goto fail;
157
158 if( x264_macroblock_thread_allocate( look_h, 1 ) < 0 )
159 goto fail;
160
161 if( x264_pthread_create( &look->thread_handle, NULL, (void*)x264_lookahead_thread, look_h ) )
162 goto fail;
163 look->b_thread_active = 1;
164
165 return 0;
166 fail:
167 x264_free( look );
168 return -1;
169 }
170
x264_lookahead_delete(x264_t * h)171 void x264_lookahead_delete( x264_t *h )
172 {
173 if( h->param.i_sync_lookahead )
174 {
175 x264_pthread_mutex_lock( &h->lookahead->ifbuf.mutex );
176 h->lookahead->b_exit_thread = 1;
177 x264_pthread_cond_broadcast( &h->lookahead->ifbuf.cv_fill );
178 x264_pthread_mutex_unlock( &h->lookahead->ifbuf.mutex );
179 x264_pthread_join( h->lookahead->thread_handle, NULL );
180 x264_macroblock_cache_free( h->thread[h->param.i_threads] );
181 x264_macroblock_thread_free( h->thread[h->param.i_threads], 1 );
182 x264_free( h->thread[h->param.i_threads] );
183 }
184 x264_sync_frame_list_delete( &h->lookahead->ifbuf );
185 x264_sync_frame_list_delete( &h->lookahead->next );
186 if( h->lookahead->last_nonb )
187 x264_frame_push_unused( h, h->lookahead->last_nonb );
188 x264_sync_frame_list_delete( &h->lookahead->ofbuf );
189 x264_free( h->lookahead );
190 }
191
x264_lookahead_put_frame(x264_t * h,x264_frame_t * frame)192 void x264_lookahead_put_frame( x264_t *h, x264_frame_t *frame )
193 {
194 if( h->param.i_sync_lookahead )
195 x264_sync_frame_list_push( &h->lookahead->ifbuf, frame );
196 else
197 x264_sync_frame_list_push( &h->lookahead->next, frame );
198 }
199
x264_lookahead_is_empty(x264_t * h)200 int x264_lookahead_is_empty( x264_t *h )
201 {
202 int b_empty;
203
204 x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
205 x264_pthread_mutex_lock( &h->lookahead->next.mutex );
206 b_empty = !h->lookahead->next.i_size && !h->lookahead->ofbuf.i_size;
207 x264_pthread_mutex_unlock( &h->lookahead->next.mutex );
208 x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
209 return b_empty;
210 }
211
x264_lookahead_encoder_shift(x264_t * h)212 static void x264_lookahead_encoder_shift( x264_t *h )
213 {
214 int i_frames;
215
216 if( !h->lookahead->ofbuf.i_size )
217 return;
218 i_frames = h->lookahead->ofbuf.list[0]->i_bframes + 1;
219 while( i_frames-- )
220 {
221 x264_frame_push( h->frames.current, x264_frame_shift( h->lookahead->ofbuf.list ) );
222 h->lookahead->ofbuf.i_size--;
223 }
224 x264_pthread_cond_broadcast( &h->lookahead->ofbuf.cv_empty );
225 }
226
x264_lookahead_get_frames(x264_t * h)227 void x264_lookahead_get_frames( x264_t *h )
228 {
229 if( h->param.i_sync_lookahead )
230 { /* We have a lookahead thread, so get frames from there */
231 x264_pthread_mutex_lock( &h->lookahead->ofbuf.mutex );
232 while( !h->lookahead->ofbuf.i_size && h->lookahead->b_thread_active )
233 x264_pthread_cond_wait( &h->lookahead->ofbuf.cv_fill, &h->lookahead->ofbuf.mutex );
234 x264_lookahead_encoder_shift( h );
235 x264_pthread_mutex_unlock( &h->lookahead->ofbuf.mutex );
236 }
237 else
238 { /* We are not running a lookahead thread, so perform all the slicetype decide on the fly */
239 int shift_frames;
240
241 if( h->frames.current[0] || !h->lookahead->next.i_size )
242 return;
243
244 x264_stack_align( x264_slicetype_decide, h );
245 x264_lookahead_update_last_nonb( h, h->lookahead->next.list[0] );
246 shift_frames = h->lookahead->next.list[0]->i_bframes + 1;
247 x264_lookahead_shift( &h->lookahead->ofbuf, &h->lookahead->next, shift_frames );
248
249 /* For MB-tree and VBV lookahead, we have to perform propagation analysis on I-frames too. */
250 if( h->lookahead->b_analyse_keyframe && IS_X264_TYPE_I( h->lookahead->last_nonb->i_type ) )
251 x264_stack_align( x264_slicetype_analyse, h, shift_frames );
252
253 x264_lookahead_encoder_shift( h );
254 }
255 }
256