Changeset f913159da06612d0278f87bd8160dafaa8a30b53

Timestamp:

10/06/07 13:26:34 (10 months ago)

Author:

Jean-Paul Saman <jpsaman@videolan.org>

git-committer:

Jean-Paul Saman <jpsaman@videolan.org> 1191669994 +0000

git-parent:

[c7d5b899f524df1c54599b42b6d4cb115644f1ec]

git-author:

Jean-Paul Saman <jpsaman@videolan.org> 1191669994 +0000

Message:

Patch for v4l2 support by Richard Hosking <richard AT hovis DOT net>

Files:

• THANKS (modified) (1 diff)
• modules/access/v4l2.c (modified) (21 diffs)

THANKS

@@ -173 +173 @@
-Remco Poortinga <poortinga at telin.nl> - IPv6 multicast patch
-Rene Gollent <rgollent at u.arizona.edu> - BeOS interface fix
+Richard Hosking <richard at hovis.net> - v4l2 support
-Rob Casey (rob dot casey AT swishgroup dot com dot au) - Amino RTSP fix
-Rudolf Cornelissen <rag.cornelissen at inter.nl.net> - BeOS fixes

modules/access/v4l2.c

@@ -3 +3 @@
- *****************************************************************************
- * Copyright (C) 2002-2004 the VideoLAN team
-
+2
- *
- * Author: Benjamin Pracht <bigben at videolan dot org>
+ *         Richard Hosking <richard at hovis dot net>
- *
- * This program is free software; you can redistribute it and/or modify
@@ -19 +20 @@
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
-
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-/*****************************************************************************
@@ -37 +51 @@
-#include <sys/ioctl.h>
-#include <sys/errno.h>
+#include <sys/mman.h>
-
-#include <asm/types.h>          /* for videodev2.h */
@@ -42 +57 @@
-#include <linux/videodev2.h>
-
+#include <sys/soundcard.h>
+
-/*****************************************************************************
- * Module descriptior
- 
+
-
-static int  Open ( vlc_object_t * );
@@ -53 +70 @@
-    "Name of the device to use. " \
-    "If you don't specify anything, /dev/video0 will be used.")
+#define ADEV_TEXT N_("Audio device name")
+#define ADEV_LONGTEXT N_( \
+    "Name of the audio device to use. " \
+    "If you don't specify anything, no audio device will be used.")
+#define STANDARD_TEXT N_( "Standard" )
+#define STANDARD_LONGTEXT N_( \
+    "Video standard (Default, SECAM, PAL, or NTSC)." )
+#define CHROMA_TEXT N_("Video input chroma format")
+#define CHROMA_LONGTEXT N_( \
+    "Force the Video4Linux2 video device to use a specific chroma format " \
+    "(eg. I420, RV24, etc.)")
-#define INPUT_TEXT N_( "Input" )
-#define INPUT_LONGTEXT N_( \
-    "Input of the card to use (Usually, 0 = tuner, " \
-    "1 = composite, 2 = svideo)." )
-
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-
-vlc_module_begin();
@@ -67 +126 @@
-    add_string( "v4l2-dev", "/dev/video0", 0, DEV_TEXT, DEV_LONGTEXT,
-                VLC_FALSE );
+    add_string( "v4l2-adev", "/dev/dsp", 0, DEV_TEXT, DEV_LONGTEXT,
+                VLC_FALSE );
+    add_integer( "v4l2-standard", 0, NULL, STANDARD_TEXT, STANDARD_LONGTEXT,
+                VLC_FALSE );
+    change_integer_list( i_standards_list, psz_standards_list_text, 0 );
+    add_string( "v4l2-chroma", NULL, NULL, CHROMA_TEXT, CHROMA_LONGTEXT,
+                VLC_TRUE );
-    add_integer( "v4l2-input", 0, NULL, INPUT_TEXT, INPUT_LONGTEXT,
-                VLC_TRUE );
+    add_integer( "v4l2-io", IO_METHOD_MMAP, NULL, IOMETHOD_TEXT, IOMETHOD_LONGTEXT,
+                VLC_FALSE );
+    change_integer_list( i_iomethod_list, psz_iomethod_list_text, 0 );
+    add_float( "v4l2-fps", 0, NULL, FPS_TEXT, FPS_LONGTEXT, VLC_TRUE );
+    add_bool( "v4l2-stereo", VLC_TRUE, NULL, STEREO_TEXT, STEREO_LONGTEXT,
+                VLC_TRUE );
+    add_integer( "v4l2-samplerate", 48000, NULL, SAMPLERATE_TEXT,
+                SAMPLERATE_LONGTEXT, VLC_TRUE );
+    add_integer( "v4l2-caching", DEFAULT_PTS_DELAY / 1000, NULL,
+                CACHING_TEXT, CACHING_LONGTEXT, VLC_TRUE );
-
-    add_shortcut( "v4l2" );
@@ -79 +155 @@
- *****************************************************************************/
-
-
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+
-static int Control( demux_t *, int, va_list );
-
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-
-struct demux_sys_t
-{
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-    struct v4l2_capability dev_cap;
@@ -96 +221 @@
-    struct v4l2_input *p_inputs;
-    int i_selected_input;
+    
+    int i_standard;
+    struct v4l2_standard *p_standards;
+    v4l2_std_id i_selected_standard_id;
-
-    int i_audio;
@@ -106 +235 @@
-    int i_codec;
-    struct v4l2_fmtdesc *p_codecs;
+    
+    struct buffer_t *p_buffers;
+    unsigned int i_nbuffers;
+    
+    int i_width;
+    int i_height;
+    float f_fps;            /* <= 0.0 mean to grab at full rate */
+    mtime_t i_video_pts;    /* only used when f_fps > 0 */
+    int i_fourcc;
+    
+    picture_t pic;
+    int i_video_frame_size;
+    
+    es_out_id_t *p_es_video;
+    
+    /* Audio */
+    int i_sample_rate;
+    vlc_bool_t b_stereo;
+    int i_audio_max_frame_size;
+    block_t *p_block_audio;
+    es_out_id_t *p_es_audio;
-};
-
-/*****************************************************************************
-
+2
- *****************************************************************************
- *
@@ -119 +269 @@
-    demux_t     *p_demux = (demux_t*)p_this;
-    demux_sys_t *p_sys;
-
+
+
+
-    /* Only when selected */
-
-
+
-
-    /* Set up p_demux */
-    p_demux->pf_control = Control;
+    p_demux->pf_demux = Demux;
-    p_demux->info.i_update = 0;
-    p_demux->info.i_title = 0;
@@ -133 +285 @@
-    if( p_sys == NULL ) return VLC_ENOMEM;
-    memset( p_sys, 0, sizeof( demux_sys_t ) );
-
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-    return VLC_SUCCESS;
@@ -144 +415 @@
-
-/*****************************************************************************
+ * ParseMRL: parse the options contained in the MRL
+ *****************************************************************************/
+static void ParseMRL( demux_t *p_demux )
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+
+    char *psz_dup = strdup( p_demux->psz_path );
+    char *psz_parser = psz_dup;
+
+    while( *psz_parser && *psz_parser != ':' )
+    {
+        psz_parser++;
+    }
+
+    if( *psz_parser == ':' )
+    {
+        /* read options */
+        for( ;; )
+        {
+            *psz_parser++ = '\0';
+            
+            if( !strncmp( psz_parser, "adev=", strlen( "adev=" ) ) )
+            {
+                int  i_len;
+
+                psz_parser += strlen( "adev=" );
+                if( strchr( psz_parser, ':' ) )
+                {
+                    i_len = strchr( psz_parser, ':' ) - psz_parser;
+                }
+                else
+                {
+                    i_len = strlen( psz_parser );
+                }
+
+                p_sys->psz_adev = strndup( psz_parser, i_len );
+
+                psz_parser += i_len; 
+            }
+            else if( !strncmp( psz_parser, "standard=", strlen( "standard=" ) ) )
+            {
+                psz_parser += strlen( "standard=" );
+                if( !strncmp( psz_parser, "pal", strlen( "pal" ) ) )
+                {
+                    p_sys->i_selected_standard_id = V4L2_STD_PAL;
+                    psz_parser += strlen( "pal" );
+                }
+                else if( !strncmp( psz_parser, "ntsc", strlen( "ntsc" ) ) )
+                {
+                    p_sys->i_selected_standard_id = V4L2_STD_NTSC;
+                    psz_parser += strlen( "ntsc" );
+                }
+                else if( !strncmp( psz_parser, "secam", strlen( "secam" ) ) )
+                {
+                    p_sys->i_selected_standard_id = V4L2_STD_SECAM;
+                    psz_parser += strlen( "secam" );
+                }
+                else if( !strncmp( psz_parser, "default", strlen( "default" ) ) )
+                {
+                    p_sys->i_selected_standard_id = V4L2_STD_UNKNOWN;
+                    psz_parser += strlen( "default" );
+                }
+                else
+                {
+                    p_sys->i_selected_standard_id = i_standards_list[strtol( psz_parser, &psz_parser, 0 )];
+                }
+            }
+            else if( !strncmp( psz_parser, "chroma=", strlen( "chroma=" ) ) )
+            {
+                int  i_len;
+
+                psz_parser += strlen( "chroma=" );
+                if( strchr( psz_parser, ':' ) )
+                {
+                    i_len = strchr( psz_parser, ':' ) - psz_parser;
+                }
+                else
+                {
+                    i_len = strlen( psz_parser );
+                }
+
+                char* chroma = strndup( psz_parser, i_len );
+                p_sys->i_fourcc = GetChromaFromFourcc( chroma );
+                free( chroma );                
+
+                psz_parser += i_len; 
+            }
+            else if( !strncmp( psz_parser, "input=", strlen( "input=" ) ) )
+            {
+                p_sys->i_selected_input = strtol( psz_parser + strlen( "input=" ),
+                                       &psz_parser, 0 );
+            }            
+            else if( !strncmp( psz_parser, "fps=", strlen( "fps=" ) ) )
+            {
+                p_sys->f_fps = strtof( psz_parser + strlen( "fps=" ),
+                                       &psz_parser );
+            }
+            else if( !strncmp( psz_parser, "io=", strlen( "io=" ) ) )
+            {
+                psz_parser += strlen( "io=" );
+                if( !strncmp( psz_parser, "read", strlen( "read" ) ) )
+                {
+                    p_sys->io = IO_METHOD_READ;
+                    psz_parser += strlen( "read" );
+                }
+                else if( !strncmp( psz_parser, "mmap", strlen( "mmap" ) ) )
+                {
+                    p_sys->io = IO_METHOD_MMAP;
+                    psz_parser += strlen( "mmap" );
+                }
+                else if( !strncmp( psz_parser, "userptr", strlen( "userptr" ) ) )
+                {
+                    p_sys->io = IO_METHOD_USERPTR;
+                    psz_parser += strlen( "userptr" );
+                }
+                else
+                {
+                    p_sys->io = strtol( psz_parser, &psz_parser, 0 );
+                }
+            }
+            else if( !strncmp( psz_parser, "samplerate=",
+                               strlen( "samplerate=" ) ) )
+            {
+                p_sys->i_sample_rate =
+                    strtol( psz_parser + strlen( "samplerate=" ),
+                            &psz_parser, 0 );
+            }
+            else if( !strncmp( psz_parser, "stereo", strlen( "stereo" ) ) )
+            {
+                psz_parser += strlen( "stereo" );
+                p_sys->b_stereo = VLC_TRUE;
+            }
+            else if( !strncmp( psz_parser, "mono", strlen( "mono" ) ) )
+            {
+                psz_parser += strlen( "mono" );
+                p_sys->b_stereo = VLC_FALSE;
+            }
+            else if( !strncmp( psz_parser, "caching=", strlen( "caching=" ) ) )
+            {
+                p_sys->i_pts = strtol( psz_parser + strlen( "caching=" ),
+                                       &psz_parser, DEFAULT_PTS_DELAY / 1000 );
+            }
+            else
+            {
+                msg_Warn( p_demux, "unknown option" );
+            }
+
+            while( *psz_parser && *psz_parser != ':' )
+            {
+                psz_parser++;
+            }
+
+            if( *psz_parser == '\0' )
+            {
+                break;
+            }
+        }
+    }
+
+    /* Main device */
+    if( *psz_dup )
+    {
+        p_sys->psz_device = strdup( psz_dup );
+    }
+    if( psz_dup ) free( psz_dup );
+}
+
+/*****************************************************************************
- * Close: close device, free resources
- *****************************************************************************/
@@ -149 +588 @@
-{
-    demux_t     *p_demux = (demux_t *)p_this;
-
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-    if( p_sys->i_fd_video >= 0 ) close( p_sys->i_fd_video );
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-    if( p_sys->psz_device ) free( p_sys->psz_device );
+    if( p_sys->psz_vdev ) free( p_sys->psz_vdev );
+    if( p_sys->psz_adev ) free( p_sys->psz_adev );
+    if( p_sys->p_standards ) free( p_sys->p_standards );
-    if( p_sys->p_inputs ) free( p_sys->p_inputs );
-    if( p_sys->p_tuners ) free( p_sys->p_tuners );
@@ -166 +671 @@
-static int Control( demux_t *p_demux, int i_query, va_list args )
-{
+    demux_sys_t *p_sys = p_demux->p_sys;
+    vlc_bool_t *pb;
+    int64_t    *pi64;
+
+    switch( i_query )
+    {
+        /* Special for access_demux */
+        case DEMUX_CAN_PAUSE:
+        case DEMUX_SET_PAUSE_STATE:
+        case DEMUX_CAN_CONTROL_PACE:
+            pb = (vlc_bool_t*)va_arg( args, vlc_bool_t * );
+            *pb = VLC_FALSE;
+            return VLC_SUCCESS;
+
+        case DEMUX_GET_PTS_DELAY:
+            pi64 = (int64_t*)va_arg( args, int64_t * );
+            *pi64 = (int64_t)p_sys->i_pts * 1000;
+            return VLC_SUCCESS;
+
+        case DEMUX_GET_TIME:
+            pi64 = (int64_t*)va_arg( args, int64_t * );
+            *pi64 = mdate();
+            return VLC_SUCCESS;
+
+        /* TODO implement others */
+        default:
+            return VLC_EGENERIC;
+    }
+
-    return VLC_EGENERIC;
-}
-
-/*****************************************************************************
-
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-    return 1;
-}
-
+/*****************************************************************************
+ * GrabVideo: Grab a video frame
+ *****************************************************************************/
+static block_t* GrabVideo( demux_t *p_demux )
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+
+    block_t *p_block = NULL;
+    struct v4l2_buffer buf;
+
+    if( p_sys->f_fps >= 0.1 && p_sys->i_video_pts > 0 )
+    {
+        mtime_t i_dur = (mtime_t)((double)1000000 / (double)p_sys->f_fps);
+
+        /* Did we wait long enough ? (frame rate reduction) */
+        if( p_sys->i_video_pts + i_dur > mdate() ) return 0;
+    }
+    
+    /* Grab Video Frame */
+    switch( p_sys->io )
+    {
+    case IO_METHOD_READ:
+        if( read( p_sys->i_fd_video, p_sys->p_buffers[0].start, p_sys->p_buffers[0].length ) )
+        {
+            switch( errno ) 
+            {
+            case EAGAIN:
+                return 0;
+            case EIO:
+                /* Could ignore EIO, see spec. */
+                /* fall through */
+            default:
+                msg_Err( p_demux, "Failed to read frame" );
+                return 0;
+            }        
+        }
+        
+        p_block = ProcessVideoFrame( p_demux, (uint8_t*)p_sys->p_buffers[0].start );
+        if( !p_block ) return 0;
+        
+        break;
+        
+    case IO_METHOD_MMAP:
+        memset( &buf, 0, sizeof(buf) );
+        buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        buf.memory = V4L2_MEMORY_MMAP;
+        
+        /* Wait for next frame */
+        if (ioctl( p_sys->i_fd_video, VIDIOC_DQBUF, &buf ) < 0 )
+        {
+            switch( errno ) 
+            {
+            case EAGAIN:
+                return 0;
+            case EIO:
+                /* Could ignore EIO, see spec. */
+                /* fall through */
+            default:
+                msg_Err( p_demux, "Failed to wait (VIDIOC_DQBUF)" );
+                return 0;
+            }
+        }
+
+        if( buf.index >= p_sys->i_nbuffers ) {
+            msg_Err( p_demux, "Failed capturing new frame as i>=nbuffers" );
+            return 0;
+        }
+        
+        p_block = ProcessVideoFrame( p_demux, p_sys->p_buffers[buf.index].start );
+        if( !p_block ) return 0;
+
+        /* Unlock */    
+        if( ioctl( p_sys->i_fd_video, VIDIOC_QBUF, &buf ) < 0 )
+        {
+            msg_Err (p_demux, "Failed to unlock (VIDIOC_QBUF)");
+            return 0;
+        }
+    
+        break;
+        
+    case IO_METHOD_USERPTR:        
+        memset( &buf, 0, sizeof(buf) );
+        buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        buf.memory = V4L2_MEMORY_USERPTR;
+        
+        /* Wait for next frame */
+        if (ioctl( p_sys->i_fd_video, VIDIOC_DQBUF, &buf ) < 0 )
+        {
+            switch( errno ) 
+            {
+            case EAGAIN:
+                return 0;
+            case EIO:
+                /* Could ignore EIO, see spec. */
+                /* fall through */
+            default:
+                msg_Err( p_demux, "Failed to wait (VIDIOC_DQBUF)" );
+                return 0;
+            }
+        }
+
+        /* Find frame? */
+        unsigned int i;
+        for( i = 0; i < p_sys->i_nbuffers; i++ )
+        {
+            if( buf.m.userptr == (unsigned long)p_sys->p_buffers[i].start && 
+                buf.length == p_sys->p_buffers[i].length ) break;
+        }
+
+        if( i >= p_sys->i_nbuffers ) {
+            msg_Err( p_demux, "Failed capturing new frame as i>=nbuffers" );
+            return 0;
+        }
+        
+        p_block = ProcessVideoFrame( p_demux, (uint8_t*)buf.m.userptr );
+        if( !p_block ) return 0;
+
+        /* Unlock */    
+        if( ioctl( p_sys->i_fd_video, VIDIOC_QBUF, &buf ) < 0 )
+        {
+            msg_Err (p_demux, "Failed to unlock (VIDIOC_QBUF)");
+            return 0;
+        }
+        
+        break;
+       
+    }
+    
+    /* Timestamp */
+    p_sys->i_video_pts = p_block->i_pts = p_block->i_dts = mdate();
+    
+    return p_block;
+}
+
+/*****************************************************************************
+ * ProcessVideoFrame: Helper function to take a buffer and copy it into
+ * a new block
+ *****************************************************************************/
+static block_t* ProcessVideoFrame( demux_t *p_demux, uint8_t *p_frame )
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+    block_t *p_block;
+
+    if( !p_frame ) return 0;
+            
+    /* New block */
+    if( !( p_block = block_New( p_demux, p_sys->i_video_frame_size ) ) )
+    {
+        msg_Warn( p_demux, "Cannot get new block" );
+        return 0;
+    }
+
+    /* Copy frame */
+    memcpy( p_block->p_buffer, p_frame, p_sys->i_video_frame_size );
+    
+    return p_block;
+}
+
+/*****************************************************************************
+ * GrabAudio: Grab an audio frame
+ *****************************************************************************/
+static block_t* GrabAudio( demux_t *p_demux )
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+    struct audio_buf_info buf_info;
+    int i_read, i_correct;
+    block_t *p_block;
+    
+    /* Copied from v4l.c */
+
+    if( p_sys->p_block_audio ) p_block = p_sys->p_block_audio;
+    else p_block = block_New( p_demux, p_sys->i_audio_max_frame_size );
+
+    if( !p_block )
+    {
+        msg_Warn( p_demux, "cannot get block" );
+        return 0;
+    }
+
+    p_sys->p_block_audio = p_block;
+
+    i_read = read( p_sys->i_fd_audio, p_block->p_buffer,
+                   p_sys->i_audio_max_frame_size );                  
+
+    if( i_read <= 0 ) return 0;
+
+    p_block->i_buffer = i_read;
+    p_sys->p_block_audio = 0;
+
+    /* Correct the date because of kernel buffering */
+    i_correct = i_read;
+    if( ioctl( p_sys->i_fd_audio, SNDCTL_DSP_GETISPACE, &buf_info ) == 0 )
+    {
+        i_correct += buf_info.bytes;
+    }
+
+    /* Timestamp */
+    p_block->i_pts = p_block->i_dts =
+        mdate() - I64C(1000000) * (mtime_t)i_correct /
+        2 / ( p_sys->b_stereo ? 2 : 1) / p_sys->i_sample_rate;
+
+    return p_block;
+}
+
+/*****************************************************************************
+ * Helper function to initalise video IO using the Read method
+ *****************************************************************************/
+static int InitRead( demux_t *p_demux, int i_fd, unsigned int i_buffer_size ) 
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+
+    p_sys->p_buffers = calloc( 1, sizeof( *p_sys->p_buffers ) );
+    if( !p_sys->p_buffers )
+    {
+        msg_Err( p_demux, "Out of memory" );
+        goto open_failed;
+    }
+    
+    p_sys->p_buffers[0].length = i_buffer_size;
+    p_sys->p_buffers[0].start = malloc( i_buffer_size );
+    if( !p_sys->p_buffers[0].start )
+    {
+        msg_Err( p_demux, "Out of memory" );
+        goto open_failed;
+    }    
+
+    return VLC_SUCCESS;
+    
+open_failed:
+    return VLC_EGENERIC;
+    
+}
+
+/*****************************************************************************
+ * Helper function to initalise video IO using the mmap method
+ *****************************************************************************/
+static int InitMmap( demux_t *p_demux, int i_fd ) 
+{
+    demux_sys_t *p_sys = p_demux->p_sys;
+    struct v4l2_requestbuffers req;
+    
+    memset( &req, 0, sizeof(req) );
+    req.count = 4;
+    req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    req.memory = V4L2_MEMORY_MMAP;
+    
+    if( ioctl( i_fd, VIDIOC_REQBUFS, &req ) < 0 )
+    {
+        msg_Err( p_demux, "device does not support mmap i/o" );
+        goto open_failed;
+    }
+                            
+    if( req.count < 2 )
+    {
+        msg_Err( p_demux, "Insufficient buffer memory" );
+        goto open_failed;
+    }
+    
+    p_sys->p_buffers = calloc( req.count, sizeof( *p_sys->p_buffers ) );
+    if( !p_sys->p_buffers )
+    {
+        msg_Err( p_demux, "Out of memory" );
+        goto open_failed;
+    }
+    
+    for( p_sys->i_nbuffers = 0; p_sys->i_nbuffers < req.count; ++p_sys->i_nbuffers )
+    {
+        struct v4l2_buffer buf;
+    
+        memset( &buf, 0, sizeof(buf) );
+        buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        buf.memory = V4L2_MEMORY_MMAP;
+        buf.index = p_sys->i_nbuffers;
+        
+        if( ioctl( i_fd, VIDIOC_QUERYBUF, &buf ) < 0 )
+        {
+            msg_Err( p_demux, "VIDIOC_QUERYBUF" );
+            goto open_failed;
+        }
+        
+        p_sys->p_buffers[p_sys->i_nbuffers].length = buf.length;
+        p_sys->p_buffers[p_sys->i_nbuffers].start = 
+            mmap( NULL, buf.length, PROT_READ | PROT_WRITE, MAP_SHARED, p_sys->i_fd_video, buf.m