1
mirror of https://code.videolan.org/videolan/vlc synced 2024-10-03 01:31:53 +02:00
vlc/modules/demux/mjpeg.c
2010-04-13 19:29:40 +03:00

530 lines
15 KiB
C

/*****************************************************************************
* mjpeg.c : demuxes mjpeg webcam http streams
*****************************************************************************
* Copyright (C) 2004 the VideoLAN team
* $Id$
*
* Authors: Henry Jen (slowhog) <henryjen@ztune.net>
* Derk-Jan Hartman (thedj)
* Sigmund Augdal (Dnumgis)
* Laurent Aimar <fenrir@via.ecp.fr>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_demux.h>
/*****************************************************************************
* Module descriptor
*****************************************************************************/
static int Open ( vlc_object_t * );
static void Close( vlc_object_t * );
#define FPS_TEXT N_("Frames per Second")
#define FPS_LONGTEXT N_("This is the desired frame rate when " \
"playing MJPEG from a file. Use 0 (this is the default value) for a " \
"live stream (from a camera).")
vlc_module_begin ()
set_shortname( "MJPEG")
set_description( N_("M-JPEG camera demuxer") )
set_capability( "demux", 5 )
set_callbacks( Open, Close )
set_category( CAT_INPUT )
set_subcategory( SUBCAT_INPUT_DEMUX )
add_float( "mjpeg-fps", 0.0, NULL, FPS_TEXT, FPS_LONGTEXT, false )
vlc_module_end ()
/*****************************************************************************
* Local prototypes
*****************************************************************************/
static int MimeDemux( demux_t * );
static int MjpgDemux( demux_t * );
static int Control( demux_t *, int i_query, va_list args );
struct demux_sys_t
{
es_format_t fmt;
es_out_id_t *p_es;
bool b_still;
mtime_t i_still_end;
mtime_t i_still_length;
mtime_t i_time;
mtime_t i_frame_length;
char *psz_separator;
int i_frame_size_estimate;
const uint8_t *p_peek;
int i_data_peeked;
int i_level;
};
/*****************************************************************************
* Peek: Helper function to peek data with incremental size.
* \return false if peek no more data, true otherwise.
*****************************************************************************/
static bool Peek( demux_t *p_demux, bool b_first )
{
int i_data;
demux_sys_t *p_sys = p_demux->p_sys;
if( b_first )
{
p_sys->i_data_peeked = 0;
}
else if( p_sys->i_data_peeked == p_sys->i_frame_size_estimate )
{
p_sys->i_frame_size_estimate += 5120;
}
i_data = stream_Peek( p_demux->s, &p_sys->p_peek,
p_sys->i_frame_size_estimate );
if( i_data == p_sys->i_data_peeked )
{
msg_Warn( p_demux, "no more data" );
return false;
}
p_sys->i_data_peeked = i_data;
if( i_data <= 0 )
{
msg_Warn( p_demux, "cannot peek data" );
return false;
}
return true;
}
/*****************************************************************************
* GetLine: Internal function used to dup a line of string from the buffer
*****************************************************************************/
static char* GetLine( demux_t *p_demux, int *p_pos )
{
demux_sys_t *p_sys = p_demux->p_sys;
const uint8_t *p_buf;
int i_size;
int i;
char *p_line;
while( *p_pos >= p_sys->i_data_peeked )
{
if( ! Peek( p_demux, false ) )
{
return NULL;
}
}
p_buf = p_sys->p_peek + *p_pos;
i_size = p_sys->i_data_peeked - *p_pos;
i = 0;
while( p_buf[i] != '\n' )
{
i++;
if( i == i_size )
{
if( ! Peek( p_demux, false ) )
{
return NULL;
}
p_buf = p_sys->p_peek + *p_pos;
i_size = p_sys->i_data_peeked - *p_pos;
}
}
*p_pos += ( i + 1 );
if( i > 0 && '\r' == p_buf[i - 1] )
{
i--;
}
p_line = malloc( i + 1 );
if( p_line == NULL )
return NULL;
strncpy ( p_line, (char*)p_buf, i );
p_line[i] = '\0';
// msg_Dbg( p_demux, "i = %d, pos = %d, %s", i, *p_pos, p_line );
return p_line;
}
/*****************************************************************************
* CheckMimeHeader: Internal function used to verify and skip mime header
* \param p_header_size Return size of MIME header, 0 if no MIME header
* detected, minus value if error
* \return true if content type is image/jpeg, false otherwise
*****************************************************************************/
static bool CheckMimeHeader( demux_t *p_demux, int *p_header_size )
{
bool b_jpeg = false;
int i_pos;
char *psz_line;
char *p_ch;
demux_sys_t *p_sys = p_demux->p_sys;
if( !Peek( p_demux, true ) )
{
msg_Err( p_demux, "cannot peek" );
*p_header_size = -1;
return false;
}
if( p_sys->i_data_peeked < 5)
{
msg_Err( p_demux, "data shortage" );
*p_header_size = -2;
return false;
}
if( strncmp( (char *)p_sys->p_peek, "--", 2 ) != 0
&& strncmp( (char *)p_sys->p_peek, "\r\n--", 4 ) != 0 )
{
*p_header_size = 0;
return false;
}
i_pos = *p_sys->p_peek == '-' ? 2 : 4;
psz_line = GetLine( p_demux, &i_pos );
if( NULL == psz_line )
{
msg_Err( p_demux, "no EOL" );
*p_header_size = -3;
return false;
}
/* Read the separator and remember it if not yet stored */
if( p_sys->psz_separator == NULL )
{
p_sys->psz_separator = psz_line;
msg_Dbg( p_demux, "Multipart MIME detected, using separator: %s",
p_sys->psz_separator );
}
else
{
if( strcmp( psz_line, p_sys->psz_separator ) )
{
msg_Warn( p_demux, "separator %s does not match %s", psz_line,
p_sys->psz_separator );
}
free( psz_line );
}
psz_line = GetLine( p_demux, &i_pos );
while( psz_line && *psz_line )
{
if( !strncasecmp( psz_line, "Content-Type:", 13 ) )
{
p_ch = psz_line + 13;
while( *p_ch != '\0' && ( *p_ch == ' ' || *p_ch == '\t' ) ) p_ch++;
if( strncasecmp( p_ch, "image/jpeg", 10 ) )
{
msg_Warn( p_demux, "%s, image/jpeg is expected", psz_line );
b_jpeg = false;
}
else
{
b_jpeg = true;
}
}
else
{
msg_Dbg( p_demux, "discard MIME header: %s", psz_line );
}
free( psz_line );
psz_line = GetLine( p_demux, &i_pos );
}
if( NULL == psz_line )
{
msg_Err( p_demux, "no EOL" );
*p_header_size = -3;
return false;
}
free( psz_line );
*p_header_size = i_pos;
return b_jpeg;
}
static int SendBlock( demux_t *p_demux, int i )
{
demux_sys_t *p_sys = p_demux->p_sys;
block_t *p_block;
if( ( p_block = stream_Block( p_demux->s, i ) ) == NULL )
{
msg_Warn( p_demux, "cannot read data" );
return 0;
}
if( !p_sys->i_frame_length || !p_sys->i_time )
{
p_sys->i_time = p_block->i_dts = p_block->i_pts = mdate();
}
else
{
p_block->i_dts = p_block->i_pts = VLC_TS_0 + p_sys->i_time;
p_sys->i_time += p_sys->i_frame_length;
}
/* set PCR */
es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block->i_pts );
es_out_Send( p_demux->out, p_sys->p_es, p_block );
if( p_sys->b_still )
{
p_sys->i_still_end = mdate() + p_sys->i_still_length;
}
return 1;
}
/*****************************************************************************
* Open: check file and initializes structures
*****************************************************************************/
static int Open( vlc_object_t * p_this )
{
demux_t *p_demux = (demux_t*)p_this;
demux_sys_t *p_sys;
int i_size;
bool b_matched = false;
float f_fps;
p_demux->pf_control = Control;
p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
p_sys->p_es = NULL;
p_sys->i_time = 0;
p_sys->i_level = 0;
p_sys->psz_separator = NULL;
p_sys->i_frame_size_estimate = 15 * 1024;
b_matched = CheckMimeHeader( p_demux, &i_size);
if( b_matched )
{
p_demux->pf_demux = MimeDemux;
stream_Read( p_demux->s, NULL, i_size );
}
else if( 0 == i_size )
{
/* 0xffd8 identify a JPEG SOI */
if( p_sys->p_peek[0] == 0xFF && p_sys->p_peek[1] == 0xD8 )
{
msg_Dbg( p_demux, "JPEG SOI marker detected" );
p_demux->pf_demux = MjpgDemux;
p_sys->i_level++;
}
else
{
goto error;
}
}
else
{
goto error;
}
f_fps = var_CreateGetFloat( p_demux, "mjpeg-fps" );
p_sys->i_frame_length = 0;
/* Check for jpeg file extension */
p_sys->b_still = false;
p_sys->i_still_end = 0;
if( demux_IsPathExtension( p_demux, ".jpeg" ) ||
demux_IsPathExtension( p_demux, ".jpg" ) )
{
p_sys->b_still = true;
if( f_fps )
{
p_sys->i_still_length = 1000000.0 / f_fps;
}
else
{
/* Defaults to 1fps */
p_sys->i_still_length = 1000000;
}
}
else if ( f_fps )
{
p_sys->i_frame_length = 1000000.0 / f_fps;
}
es_format_Init( &p_sys->fmt, VIDEO_ES, 0 );
p_sys->fmt.i_codec = VLC_CODEC_MJPG;
p_sys->p_es = es_out_Add( p_demux->out, &p_sys->fmt );
return VLC_SUCCESS;
error:
free( p_sys );
return VLC_EGENERIC;
}
/*****************************************************************************
* Demux: read packet and send them to decoders
*****************************************************************************
* Returns -1 in case of error, 0 in case of EOF, 1 otherwise
*****************************************************************************/
static int MjpgDemux( demux_t *p_demux )
{
demux_sys_t *p_sys = p_demux->p_sys;
int i;
if( p_sys->b_still && p_sys->i_still_end )
{
/* Still frame, wait until the pause delay is gone */
mwait( p_sys->i_still_end );
p_sys->i_still_end = 0;
return 1;
}
if( !Peek( p_demux, true ) )
{
msg_Warn( p_demux, "cannot peek data" );
return 0;
}
if( p_sys->i_data_peeked < 4 )
{
msg_Warn( p_demux, "data shortage" );
return 0;
}
i = 3;
FIND_NEXT_EOI:
while( !( 0xFF == p_sys->p_peek[i-1] && 0xD9 == p_sys->p_peek[i] ) )
{
if( 0xFF == p_sys->p_peek[i-1] && 0xD8 == p_sys->p_peek[i] )
{
p_sys->i_level++;
msg_Dbg( p_demux, "we found another JPEG SOI at %d", i );
}
i++;
if( i >= p_sys->i_data_peeked )
{
msg_Dbg( p_demux, "did not find JPEG EOI in %d bytes",
p_sys->i_data_peeked );
if( !Peek( p_demux, false ) )
{
msg_Warn( p_demux, "no more data is available at the moment" );
return 0;
}
}
}
i++;
msg_Dbg( p_demux, "JPEG EOI detected at %d", i );
p_sys->i_level--;
if( p_sys->i_level > 0 )
goto FIND_NEXT_EOI;
return SendBlock( p_demux, i );
}
static int MimeDemux( demux_t *p_demux )
{
demux_sys_t *p_sys = p_demux->p_sys;
int i_size, i;
bool b_match = CheckMimeHeader( p_demux, &i_size );
if( i_size > 0 )
{
stream_Read( p_demux->s, NULL, i_size );
}
else if( i_size < 0 )
{
return 0;
}
else
{
// No MIME header, assume OK
b_match = true;
}
if( !Peek( p_demux, true ) )
{
msg_Warn( p_demux, "cannot peek data" );
return 0;
}
i = 0;
i_size = strlen( p_sys->psz_separator ) + 2;
if( p_sys->i_data_peeked < i_size )
{
msg_Warn( p_demux, "data shortage" );
return 0;
}
for( ;; )
{
while( !( p_sys->p_peek[i] == '-' && p_sys->p_peek[i+1] == '-' ) )
{
i++;
i_size++;
if( i_size >= p_sys->i_data_peeked )
{
msg_Dbg( p_demux, "MIME boundary not found in %d bytes of "
"data", p_sys->i_data_peeked );
if( !Peek( p_demux, false ) )
{
msg_Warn( p_demux, "no more data is available at the "
"moment" );
return 0;
}
}
}
if( !strncmp( p_sys->psz_separator, (char *)(p_sys->p_peek + i + 2),
strlen( p_sys->psz_separator ) ) )
{
break;
}
i++;
i_size++;
}
if( !b_match )
{
msg_Err( p_demux, "discard non-JPEG part" );
stream_Read( p_demux->s, NULL, i );
return 0;
}
return SendBlock( p_demux, i );
}
/*****************************************************************************
* Close: frees unused data
*****************************************************************************/
static void Close ( vlc_object_t * p_this )
{
demux_t *p_demux = (demux_t*)p_this;
demux_sys_t *p_sys = p_demux->p_sys;
free( p_sys->psz_separator );
free( p_sys );
}
/*****************************************************************************
* Control:
*****************************************************************************/
static int Control( demux_t *p_demux, int i_query, va_list args )
{
return demux_vaControlHelper( p_demux->s, 0, 0, 0, 0, i_query, args );
}