git.sesse.net Git - vlc/blob - modules/stream_out/transrate/transrate.c

   1 /*****************************************************************************
   2  * transrate.c: MPEG2 video transrating module
   3  *****************************************************************************
   4  * Copyright (C) 2003 VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   8  *          Laurent Aimar <fenrir@via.ecp.fr>
   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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #define NDEBUG 1
  31 #include <assert.h>
  32 #include <math.h>
  33
  34 #include <vlc/vlc.h>
  35 #include <vlc/sout.h>
  36 #include <vlc/input.h>
  37
  38 #include "transrate.h"
  39
  40 /*****************************************************************************
  41  * Exported prototypes
  42  *****************************************************************************/
  43 static int      Open    ( vlc_object_t * );
  44 static void     Close   ( vlc_object_t * );
  45
  46 static sout_stream_id_t *Add ( sout_stream_t *, es_format_t * );
  47 static int               Del ( sout_stream_t *, sout_stream_id_t * );
  48 static int               Send( sout_stream_t *, sout_stream_id_t *, block_t * );
  49
  50 static int  transrate_video_process( sout_stream_t *, sout_stream_id_t *, block_t *, block_t ** );
  51
  52 /*****************************************************************************
  53  * Module descriptor
  54  *****************************************************************************/
  55 vlc_module_begin();
  56     set_description( _("MPEG2 video transrating stream output") );
  57     set_capability( "sout stream", 50 );
  58     add_shortcut( "transrate" );
  59     set_callbacks( Open, Close );
  60 vlc_module_end();
  61
  62 struct sout_stream_sys_t
  63 {
  64     sout_stream_t   *p_out;
  65
  66     int             i_vbitrate;
  67     mtime_t         i_shaping_delay;
  68     int             b_mpeg4_matrix;
  69
  70     mtime_t         i_dts, i_pts;
  71 };
  72
  73 /*****************************************************************************
  74  * Open:
  75  *****************************************************************************/
  76 static int Open( vlc_object_t *p_this )
  77 {
  78     sout_stream_t     *p_stream = (sout_stream_t*)p_this;
  79     sout_stream_sys_t *p_sys;
  80     char *val;
  81
  82     p_sys = malloc( sizeof( sout_stream_sys_t ) );
  83     p_sys->p_out = sout_StreamNew( p_stream->p_sout, p_stream->psz_next );
  84
  85     p_sys->i_vbitrate   = 0;
  86
  87     if( ( val = sout_cfg_find_value( p_stream->p_cfg, "vb" ) ) )
  88     {
  89         p_sys->i_vbitrate = atoi( val );
  90         if( p_sys->i_vbitrate < 16000 )
  91         {
  92             p_sys->i_vbitrate *= 1000;
  93         }
  94     }
  95     else
  96     {
  97         p_sys->i_vbitrate = 3000000;
  98     }
  99
 100     p_sys->i_shaping_delay = 500000;
 101     if( ( val = sout_cfg_find_value( p_stream->p_cfg, "shaping" ) ) )
 102     {
 103         p_sys->i_shaping_delay = (int64_t)atoi( val ) * 1000;
 104         if( p_sys->i_shaping_delay <= 0 )
 105         {
 106             msg_Err( p_stream,
 107                      "invalid shaping ("I64Fd"ms) reseting to 500ms",
 108                      p_sys->i_shaping_delay / 1000 );
 109             p_sys->i_shaping_delay = 500000;
 110         }
 111     }
 112
 113     p_sys->b_mpeg4_matrix = 0;
 114     if( sout_cfg_find( p_stream->p_cfg, "mpeg4-matrix" ) )
 115     {
 116         p_sys->b_mpeg4_matrix = 1;
 117     }
 118
 119     msg_Dbg( p_stream, "codec video %dkb/s max gop="I64Fd"us",
 120              p_sys->i_vbitrate / 1024, p_sys->i_shaping_delay );
 121
 122     if( !p_sys->p_out )
 123     {
 124         msg_Err( p_stream, "cannot create chain" );
 125         free( p_sys );
 126         return VLC_EGENERIC;
 127     }
 128     p_stream->pf_add    = Add;
 129     p_stream->pf_del    = Del;
 130     p_stream->pf_send   = Send;
 131
 132     p_stream->p_sys     = p_sys;
 133
 134     return VLC_SUCCESS;
 135 }
 136
 137 /*****************************************************************************
 138  * Close:
 139  *****************************************************************************/
 140 static void Close( vlc_object_t * p_this )
 141 {
 142     sout_stream_t       *p_stream = (sout_stream_t *)p_this;
 143     sout_stream_sys_t   *p_sys = p_stream->p_sys;
 144
 145     sout_StreamDelete( p_sys->p_out );
 146     free( p_sys );
 147 }
 148
 149
 150 static sout_stream_id_t * Add( sout_stream_t *p_stream, es_format_t *p_fmt )
 151 {
 152     sout_stream_sys_t   *p_sys = p_stream->p_sys;
 153     sout_stream_id_t    *id;
 154
 155     id = malloc( sizeof( sout_stream_id_t ) );
 156     id->id = NULL;
 157
 158     if( p_fmt->i_cat == VIDEO_ES
 159             && p_fmt->i_codec == VLC_FOURCC('m', 'p', 'g', 'v') )
 160     {
 161         msg_Dbg( p_stream,
 162                  "creating video transrating for fcc=`%4.4s'",
 163                  (char*)&p_fmt->i_codec );
 164
 165         id->p_current_buffer = NULL;
 166         id->p_next_gop = NULL;
 167         id->i_next_gop_duration = 0;
 168         id->i_next_gop_size = 0;
 169         memset( &id->tr, 0, sizeof( transrate_t ) );
 170         id->tr.bs.i_byte_in = id->tr.bs.i_byte_out = 0;
 171         id->tr.mpeg4_matrix = p_sys->b_mpeg4_matrix;
 172
 173         /* open output stream */
 174         id->id = p_sys->p_out->pf_add( p_sys->p_out, p_fmt );
 175         id->b_transrate = VLC_TRUE;
 176     }
 177     else
 178     {
 179         msg_Dbg( p_stream, "not transrating a stream (fcc=`%4.4s')", (char*)&p_fmt->i_codec );
 180         id->id = p_sys->p_out->pf_add( p_sys->p_out, p_fmt );
 181         id->b_transrate = VLC_FALSE;
 182
 183         if( id->id == NULL )
 184         {
 185             free( id );
 186             return NULL;
 187         }
 188     }
 189
 190     return id;
 191 }
 192
 193 static int     Del      ( sout_stream_t *p_stream, sout_stream_id_t *id )
 194 {
 195     sout_stream_sys_t   *p_sys = p_stream->p_sys;
 196
 197     if( id->id )
 198     {
 199         p_sys->p_out->pf_del( p_sys->p_out, id->id );
 200     }
 201     free( id );
 202
 203     return VLC_SUCCESS;
 204 }
 205
 206 static int Send( sout_stream_t *p_stream, sout_stream_id_t *id,
 207                  block_t *p_buffer )
 208 {
 209     sout_stream_sys_t   *p_sys = p_stream->p_sys;
 210
 211     if( id->b_transrate )
 212     {
 213         block_t *p_buffer_out;
 214         /* be sure to have at least 8 bytes of padding (maybe only 4) */
 215         p_buffer = block_Realloc( p_buffer, 0, p_buffer->i_buffer + 8 );
 216         p_buffer->i_buffer -= 8;
 217         memset( &p_buffer->p_buffer[p_buffer->i_buffer], 0, 8 );
 218
 219         transrate_video_process( p_stream, id, p_buffer, &p_buffer_out );
 220
 221         if( p_buffer_out )
 222         {
 223             return p_sys->p_out->pf_send( p_sys->p_out, id->id, p_buffer_out );
 224         }
 225         return VLC_SUCCESS;
 226     }
 227     else if( id->id != NULL )
 228     {
 229         return p_sys->p_out->pf_send( p_sys->p_out, id->id, p_buffer );
 230     }
 231     else
 232     {
 233         block_Release( p_buffer );
 234         return VLC_EGENERIC;
 235     }
 236 }
 237
 238 static int transrate_video_process( sout_stream_t *p_stream,
 239                sout_stream_id_t *id, block_t *in, block_t **out )
 240 {
 241     transrate_t    *tr = &id->tr;
 242     bs_transrate_t *bs = &tr->bs;
 243
 244     *out = NULL;
 245
 246     while ( in != NULL )
 247     {
 248         block_t * p_next = in->p_next;
 249         int i_flags = in->i_flags;
 250
 251         in->p_next = NULL;
 252         block_ChainAppend( &id->p_next_gop, in );
 253         id->i_next_gop_duration += in->i_length;
 254         id->i_next_gop_size += in->i_buffer;
 255         in = p_next;
 256
 257         if( ((i_flags & BLOCK_FLAG_TYPE_I )
 258                 && id->i_next_gop_duration >= 300000)
 259               || (id->i_next_gop_duration > p_stream->p_sys->i_shaping_delay) )
 260         {
 261             mtime_t i_bitrate = (mtime_t)id->i_next_gop_size * 8000
 262                                     / (id->i_next_gop_duration / 1000);
 263             mtime_t i_new_bitrate;
 264
 265             id->tr.i_total_input = id->i_next_gop_size;
 266             id->tr.i_remaining_input = id->i_next_gop_size;
 267             id->tr.i_wanted_output = (p_stream->p_sys->i_vbitrate)
 268                                     * (id->i_next_gop_duration / 1000) / 8000;
 269             id->tr.i_current_output = 0;
 270
 271             id->p_current_buffer = id->p_next_gop;
 272
 273             while ( id->p_current_buffer != NULL )
 274             {
 275                 block_t * p_next = id->p_current_buffer->p_next;
 276                 if ( !p_stream->p_sys->b_mpeg4_matrix
 277                        && id->tr.i_wanted_output >= id->tr.i_total_input )
 278                 {
 279                     bs->i_byte_out += id->p_current_buffer->i_buffer;
 280                     id->p_current_buffer->p_next = NULL;
 281                     block_ChainAppend( out, id->p_current_buffer );
 282                 }
 283                 else
 284                 {
 285                     if ( process_frame( p_stream, id, id->p_current_buffer,
 286                                         out, 0 ) < 0 )
 287                     {
 288                         id->p_current_buffer->p_next = NULL;
 289                         block_ChainAppend( out, id->p_current_buffer );
 290                         if ( p_stream->p_sys->b_mpeg4_matrix )
 291                             id->tr.i_wanted_output = id->tr.i_total_input;
 292                     }
 293                     else
 294                     {
 295                         block_Release( id->p_current_buffer );
 296                     }
 297                 }
 298                 id->p_current_buffer = p_next;
 299             }
 300
 301             if ( id->tr.i_wanted_output < id->tr.i_total_input )
 302             {
 303                 i_new_bitrate = (mtime_t)tr->i_current_output * 8000
 304                                     / (id->i_next_gop_duration / 1000);
 305                 if (i_new_bitrate > p_stream->p_sys->i_vbitrate + 300000)
 306                     msg_Err(p_stream, "%lld -> %lld d=%lld",
 307                             i_bitrate, i_new_bitrate,
 308                             id->i_next_gop_duration);
 309                 else
 310                     msg_Dbg(p_stream, "%lld -> %lld d=%lld",
 311                             i_bitrate, i_new_bitrate,
 312                             id->i_next_gop_duration);
 313             }
 314
 315             id->p_next_gop = NULL;
 316             id->i_next_gop_duration = 0;
 317             id->i_next_gop_size = 0;
 318         }
 319     }
 320
 321     return VLC_SUCCESS;
 322 }
 323