1 /*****************************************************************************
2 * packetizer_helper.h: Packetizer helpers
3 *****************************************************************************
4 * Copyright (C) 2009 Laurent Aimar
7 * Authors: Laurent Aimar <fenrir _AT_ videolan _DOT_ org>
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License as published by
11 * the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this program; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
25 #define _PACKETIZER_H 1
27 #include <vlc_block.h>
39 typedef void (*packetizer_reset_t)( void *p_private, bool b_broken );
40 typedef block_t *(*packetizer_parse_t)( void *p_private, bool *pb_ts_used, block_t * );
41 typedef int (*packetizer_validate_t)( void *p_private, block_t * );
46 block_bytestream_t bytestream;
51 const uint8_t *p_startcode;
54 const uint8_t *p_au_prepend;
56 unsigned i_au_min_size;
59 packetizer_reset_t pf_reset;
60 packetizer_parse_t pf_parse;
61 packetizer_validate_t pf_validate;
65 static inline void packetizer_Init( packetizer_t *p_pack,
66 const uint8_t *p_startcode, int i_startcode,
67 const uint8_t *p_au_prepend, int i_au_prepend,
68 unsigned i_au_min_size,
69 packetizer_reset_t pf_reset,
70 packetizer_parse_t pf_parse,
71 packetizer_validate_t pf_validate,
74 p_pack->i_state = STATE_NOSYNC;
75 block_BytestreamInit( &p_pack->bytestream );
77 p_pack->b_flushing = false;
79 p_pack->i_au_prepend = i_au_prepend;
80 p_pack->p_au_prepend = p_au_prepend;
81 p_pack->i_au_min_size = i_au_min_size;
83 p_pack->i_startcode = i_startcode;
84 p_pack->p_startcode = p_startcode;
85 p_pack->pf_reset = pf_reset;
86 p_pack->pf_parse = pf_parse;
87 p_pack->pf_validate = pf_validate;
88 p_pack->p_private = p_private;
91 static inline void packetizer_Clean( packetizer_t *p_pack )
93 block_BytestreamRelease( &p_pack->bytestream );
96 static inline block_t *packetizer_Packetize( packetizer_t *p_pack, block_t **pp_block )
98 if( !pp_block || !*pp_block )
101 if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
103 const bool b_broken = ( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED ) != 0;
106 p_pack->i_state = STATE_NOSYNC;
107 block_BytestreamEmpty( &p_pack->bytestream );
108 p_pack->i_offset = 0;
110 p_pack->pf_reset( p_pack->p_private, b_broken );
112 block_Release( *pp_block );
116 block_BytestreamPush( &p_pack->bytestream, *pp_block );
123 switch( p_pack->i_state )
126 /* Find a startcode */
127 if( !block_FindStartcodeFromOffset( &p_pack->bytestream, &p_pack->i_offset,
128 p_pack->p_startcode, p_pack->i_startcode ) )
129 p_pack->i_state = STATE_NEXT_SYNC;
131 if( p_pack->i_offset )
133 block_SkipBytes( &p_pack->bytestream, p_pack->i_offset );
134 p_pack->i_offset = 0;
135 block_BytestreamFlush( &p_pack->bytestream );
138 if( p_pack->i_state != STATE_NEXT_SYNC )
139 return NULL; /* Need more data */
141 p_pack->i_offset = 1; /* To find next startcode */
143 case STATE_NEXT_SYNC:
144 /* Find the next startcode */
145 if( block_FindStartcodeFromOffset( &p_pack->bytestream, &p_pack->i_offset,
146 p_pack->p_startcode, p_pack->i_startcode ) )
148 if( !p_pack->b_flushing || !p_pack->bytestream.p_chain )
149 return NULL; /* Need more data */
151 /* When flusing and we don't find a startcode, suppose that
152 * the data extend up to the end */
153 block_ChainProperties( p_pack->bytestream.p_chain,
154 NULL, &p_pack->i_offset, NULL );
155 p_pack->i_offset -= p_pack->bytestream .i_offset;
157 if( p_pack->i_offset <= (size_t)p_pack->i_startcode )
161 block_BytestreamFlush( &p_pack->bytestream );
163 /* Get the new fragment and set the pts/dts */
164 block_t *p_block_bytestream = p_pack->bytestream.p_block;
166 p_pic = block_Alloc( p_pack->i_offset + p_pack->i_au_prepend );
167 p_pic->i_pts = p_block_bytestream->i_pts;
168 p_pic->i_dts = p_block_bytestream->i_dts;
170 block_GetBytes( &p_pack->bytestream, &p_pic->p_buffer[p_pack->i_au_prepend],
171 p_pic->i_buffer - p_pack->i_au_prepend );
172 if( p_pack->i_au_prepend > 0 )
173 memcpy( p_pic->p_buffer, p_pack->p_au_prepend, p_pack->i_au_prepend );
175 p_pack->i_offset = 0;
178 if( p_pic->i_buffer < p_pack->i_au_min_size )
180 block_Release( p_pic );
185 p_pic = p_pack->pf_parse( p_pack->p_private, &b_used_ts, p_pic );
188 p_block_bytestream->i_dts = VLC_TS_INVALID;
189 p_block_bytestream->i_pts = VLC_TS_INVALID;
195 p_pack->i_state = STATE_NOSYNC;
198 if( p_pack->pf_validate( p_pack->p_private, p_pic ) )
200 p_pack->i_state = STATE_NOSYNC;
201 block_Release( p_pic );
205 /* So p_block doesn't get re-added several times */
206 *pp_block = block_BytestreamPop( &p_pack->bytestream );
208 p_pack->i_state = STATE_NOSYNC;
215 static inline void packetizer_Header( packetizer_t *p_pack,
216 const uint8_t *p_header, int i_header )
218 block_t *p_init = block_Alloc( i_header );
222 memcpy( p_init->p_buffer, p_header, i_header );
224 p_pack->b_flushing = true;
227 while( ( p_pic = packetizer_Packetize( p_pack, &p_init ) ) )
228 block_Release( p_pic ); /* Should not happen (only sequence header) */
230 p_pack->i_state = STATE_NOSYNC;
231 block_BytestreamEmpty( &p_pack->bytestream );
232 p_pack->i_offset = 0;
233 p_pack->b_flushing = false;