modules/demux/mpeg/h264.c

   1 /*****************************************************************************
   2  * h264.c : H264 Video demuxer
   3  *****************************************************************************
   4  * Copyright (C) 2002-2004 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  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 General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_demux.h>
  35 #include <vlc_codec.h>
  36
  37 /*****************************************************************************
  38  * Module descriptor
  39  *****************************************************************************/
  40 static int  Open ( vlc_object_t * );
  41 static void Close( vlc_object_t * );
  42
  43 #define FPS_TEXT N_("Frames per Second")
  44 #define FPS_LONGTEXT N_("Desired frame rate for the H264 stream.")
  45
  46
  47 vlc_module_begin ()
  48     set_shortname( "H264")
  49     set_category( CAT_INPUT )
  50     set_subcategory( SUBCAT_INPUT_DEMUX )
  51     set_description( N_("H264 video demuxer" ) )
  52     set_capability( "demux", 0 )
  53     add_float( "h264-fps", 25.0, FPS_TEXT, FPS_LONGTEXT, true )
  54     set_callbacks( Open, Close )
  55     add_shortcut( "h264" )
  56 vlc_module_end ()
  57
  58 /*****************************************************************************
  59  * Local prototypes
  60  *****************************************************************************/
  61 struct demux_sys_t
  62 {
  63     mtime_t     i_dts;
  64     es_out_id_t *p_es;
  65
  66     float       f_fps;
  67     decoder_t *p_packetizer;
  68 };
  69
  70 static int Demux( demux_t * );
  71 static int Control( demux_t *, int, va_list );
  72
  73 #define H264_PACKET_SIZE 2048
  74
  75 /*****************************************************************************
  76  * Open: initializes demux structures
  77  *****************************************************************************/
  78 static int Open( vlc_object_t * p_this )
  79 {
  80     demux_t     *p_demux = (demux_t*)p_this;
  81     demux_sys_t *p_sys;
  82     const uint8_t *p_peek;
  83     es_format_t fmt;
  84
  85     if( stream_Peek( p_demux->s, &p_peek, 5 ) < 5 ) return VLC_EGENERIC;
  86
  87     if( p_peek[0] != 0x00 || p_peek[1] != 0x00 ||
  88         p_peek[2] != 0x00 || p_peek[3] != 0x01 ||
  89         (p_peek[4]&0x1F) != 7 ) /* SPS */
  90     {
  91         if( !p_demux->b_force )
  92         {
  93             msg_Warn( p_demux, "h264 module discarded (no startcode)" );
  94             return VLC_EGENERIC;
  95         }
  96
  97         msg_Err( p_demux, "this doesn't look like a H264 ES stream, "
  98                  "continuing anyway" );
  99     }
 100
 101     p_demux->pf_demux  = Demux;
 102     p_demux->pf_control= Control;
 103     p_demux->p_sys     = p_sys = malloc( sizeof( demux_sys_t ) );
 104     p_sys->p_es        = NULL;
 105     p_sys->i_dts       = 0;
 106     p_sys->f_fps       = var_CreateGetFloat( p_demux, "h264-fps" );
 107     if( p_sys->f_fps < 0.001 )
 108         p_sys->f_fps = 0.001;
 109     msg_Dbg( p_demux, "using %.2f fps", p_sys->f_fps );
 110
 111     /* Load the mpegvideo packetizer */
 112     es_format_Init( &fmt, VIDEO_ES, VLC_CODEC_H264 );
 113     p_sys->p_packetizer = demux_PacketizerNew( p_demux, &fmt, "h264" );
 114     if( !p_sys->p_packetizer )
 115     {
 116         free( p_sys );
 117         return VLC_EGENERIC;
 118     }
 119
 120     return VLC_SUCCESS;
 121 }
 122
 123 /*****************************************************************************
 124  * Close: frees unused data
 125  *****************************************************************************/
 126 static void Close( vlc_object_t * p_this )
 127 {
 128     demux_t     *p_demux = (demux_t*)p_this;
 129     demux_sys_t *p_sys = p_demux->p_sys;
 130
 131     demux_PacketizerDestroy( p_sys->p_packetizer );
 132     free( p_sys );
 133 }
 134
 135 /*****************************************************************************
 136  * Demux: reads and demuxes data packets
 137  *****************************************************************************
 138  * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
 139  *****************************************************************************/
 140 static int Demux( demux_t *p_demux)
 141 {
 142     demux_sys_t *p_sys = p_demux->p_sys;
 143     block_t *p_block_in, *p_block_out;
 144
 145     if( ( p_block_in = stream_Block( p_demux->s, H264_PACKET_SIZE ) ) == NULL )
 146     {
 147         return 0;
 148     }
 149
 150     /* m4v demuxer doesn't set pts/dts at all */
 151     p_block_in->i_dts = VLC_TS_0;
 152     p_block_in->i_pts = VLC_TS_0;
 153
 154     while( (p_block_out = p_sys->p_packetizer->pf_packetize( p_sys->p_packetizer, &p_block_in )) )
 155     {
 156         while( p_block_out )
 157         {
 158             block_t *p_next = p_block_out->p_next;
 159
 160             p_block_out->p_next = NULL;
 161
 162             if( p_sys->p_es == NULL )
 163             {
 164                 p_sys->p_packetizer->fmt_out.b_packetized = true;
 165                 p_sys->p_es = es_out_Add( p_demux->out, &p_sys->p_packetizer->fmt_out);
 166             }
 167
 168             es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_dts );
 169             p_block_out->i_dts = VLC_TS_0 + p_sys->i_dts;
 170             p_block_out->i_pts = VLC_TS_0 + p_sys->i_dts;
 171
 172             es_out_Send( p_demux->out, p_sys->p_es, p_block_out );
 173
 174             p_block_out = p_next;
 175
 176             p_sys->i_dts += (int64_t)((double)1000000.0 / p_sys->f_fps);
 177         }
 178     }
 179     return 1;
 180 }
 181
 182 /*****************************************************************************
 183  * Control:
 184  *****************************************************************************/
 185 static int Control( demux_t *p_demux, int i_query, va_list args )
 186 {
 187     /* demux_sys_t *p_sys  = p_demux->p_sys; */
 188     /* FIXME calculate the bitrate */
 189     if( i_query == DEMUX_SET_TIME )
 190         return VLC_EGENERIC;
 191     else
 192         return demux_vaControlHelper( p_demux->s,
 193                                        0, -1,
 194                                        0, 1, i_query, args );
 195 }
 196