mediarecorder(1)mediarecorder(1)NAMEmediarecorder - record movies, still images, or audio files
SYNOPSISmediarecorder [-media image | movie | audio ] [-source video | screen ]
[-device devicename] [-jack jackname] [-outputfile filename] [-fixedfile
] [-allowmenu menustring] [-execstring shellcmdstring] [-noclipbin ]
[-screensel optionsstring] [-delay n] [-duration n] [-start ] [-exitdone
] [-movieoptions optionstring] [-imageoptions optionstring]
[-audiooptions optionstring]
DESCRIPTIONmediarecorder is a graphical tool to record digital media files from the
camera, microphone, external video and audio hardware, and workstation
screen. To supplement the discussion below, you may wish to consult the
online help, accessible from the Help menu within the tool.
mediarecorder records three different types of files: movie files (such
as QuickTime), still image files (such as TIFF, JFIF or GIF), and audio
files (such as AIFF/AIFC). You can record movie or still image files
from the system camera, an external video source connected to the video
input jacks, or from the workstation screen. You can record audio files
from the system microphone, an external analog audio source connected to
the Line In jacks of your system, or from a digital audio input source.
To choose the type of file and signal source to record, click one of the
three icon buttons in the lower left corner of the mediarecorder display.
Each button presents a pop-up menu listing the signal sources from which
you can record. Each menu entry will also have a submenu listing the
available audio/video jacks or screen selection options.
To customize the parameters for recording, such as image size, frame
rate, audio rate, or compression, choose one of the options from the
Tasks menu. Each media type has its own submenu, listing several presets
appropriate for various uses. Choose the task which most closely suits
your needs.
To view the settings corresponding to a particular task, choose Show Task
Settings from the Tasks menu. To finely control recording parameters,
choose Custom Settings from the appropriate Tasks menu.
To begin recording, click the button with the circular dot on the right
side of the mediarecorder display, or choose Record from the Edit menu.
To stop recording, click the button with the square on the right side of
the mediarecorder display. To review a clip you have just recorded,
click its icon, then click the button with the triangle on the right side
of the mediarecorder display.
CLIP BIN/SAVE ALL CLIPS
The clip bin is an icon view inside the mediarecorder display. It shows
icons for image, audio, and movie files contained in the current
directory. The current directory is denoted by the path name above the
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icon display. mediarecorder will create all new media files in the
current directory.
By default, mediarecorder uses the current working directory for the clip
bin. To choose a different directory, you can edit the pathname above
the icon display, or drag a desktop icon for the desired directory into
the icon pocket next to the path name.
When mediarecorder records a file, it gives the file a name, comprised of
the type of file (image, audio, or movie), a number, and an extension for
the file type (such as .mov for QuickTime movies or .gif for GIF files).
To rename the file, click on the icon name in the clip bin, type a new
name for the file, and press Enter.
By default, mediarecorder will create a new file with a new name every
time you record. This is useful if you want to record several different
pieces of material. To record the same piece of material several times,
but keep only the best clip, uncheck the Save All Clips option on the
Options menu. When Save All Clips is unchecked, mediarecorder will
create all new clips with the same name, replacing the previous
recording.
SETTING A RECORD DELAYmediarecorder has a time delay feature, similar to the self-timer on some
photographic cameras. This is especially useful if you want to capture
open menus in another application. To set up a record delay, choose one
of the options from the Set Record Delay entry on the Edit menu, or use
the -delay option from the command line.
TEMPORARY FILES/SCRATCH DISKS
mediarecorder makes use of temporary files when recording movies. By
default, the temporary files are placed in the current working directory,
except if the environment variable TMPDIR is set. If TMPDIR is set, the
temporary files are placed in the path named by TMPDIR.
By default, mediarecorder uses only one temporary directory. It is
possible to specify more than one temporary directory for movie
recording. If you specify temporary directories on different disk
volumes, mediarecorder can record to multiple disks at once, increasing
the amount of video which can be written to disk. To do this, choose the
Set Scratch Disks command from the Options menu. Type or drop icons for
each temporary directory, then click the Add button. To remove a
directory from the list, select it and click Remove.
DIRECT MOVIE RECORDING
When mediarecorder records movies made with software codecs such as
QuickTime Video, Cinepak, or Indeo, it records the raw data to a
temporary file, then performs software compression after the video
capture is complete.
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When mediarecorder records QuickTime movies with uncompressed video, or
QuickTime movies from sources which support hardware JPEG compression, it
can record directly to the output movie file. This is faster and uses
less disk space during capture when compared to the non-direct approach.
By default, mediarecorder will perform direct recording whenever it can.
However, when mediarecorder records direct to the output file, it (by
definition) uses only one disk volume-that containing the output movie
file.
If you want to record using multiple disk volumes, you may wish to turn
off direct recording. To turn off direct recording, uncheck the "Record
directly to movie file when possible" checkbox in the Custom Settings
dialog, under the Tasks/Movie menu.
HIGH SCHEDULING PRIORITY FOR VIDEO CAPTURE
When you record movies from live video using mediarecorder, it will
attempt to run its internal video recording threads at a very high
priority. It will also attempt to pin down physical memory buffers for
video capture.
Both of these actions help achieve optimal video captures. However, in
order to take advantage of these features, you must run mediarecorder as
the root user. If you do not run mediarecorder as the root user, it will
record video just fine, but at possibly reduced efficiency compared to
what it would achieve while running as the root user.
HANDLING DROPPED VIDEO FRAMES
Depending on the disk bandwidth available, and the frame rate you have
chosen for capture, mediarecorder may not be able to write all incoming
video to disk. This occurs mostly with uncompressed video, or software
compression. Hardware-based JPEG compression, such as that supported by
the O2, Octane/IMPACT Compression, or the Cosmo Compress option board,
typically will not have problems with dropped video.
mediarecorder deals with dropped video frames by extending the duration
of video frames immediately preceding them. The resulting movie plays
properly, with some loss of motion in the places where frames were
dropped.
For many applications, it is important to record movies which contain no
dropped frames at all. To do this, check the "Abort recording if video
frames are dropped" checkbox in the Custom Settings dialog, under the
Tasks/Movie menu. When this box is checked, mediarecorder will
automatically abort any capture if it drops video frames. All movie
files created when this option is checked are thus guaranteed to contain
every video frame.
By default, the "Abort recording if video frames are dropped" option is
disabled. However, the "Video Production (JPEG)", "Video Production
(Cross-Platform)" and "Video Production, Uncompressed" tasks in the
Tasks/Movie menu will enable this option.
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mediarecorder(1)mediarecorder(1)ACHIEVING HIGH QUALITY VIDEO CAPTURES
To achieve the best video captures without dropping frames, it helps to
observe the following guidelines:
You are strongly advised to run mediarecorder as the root user. See the
section entitled "High Scheduling Priority for Video Capture" elsewhere
in this manual page.
Consider devoting one or more entire disk drives solely as scratch disks
for video recording. Furthermore, you should delete all files from each
drive before each capture. To direct mediarecorder to use particular
disks for scratch purposes, see the sections entitled "Temporary
Files/Scratch Disks" and "Direct Movie Recording" elsewhere in this
manual page.
The video signal you use should be stable and free of distortion.
Examples include professional or prosumer-quality VTRs, laserdisc
players, or any time-base corrected video source. A weak or distorted
video signal (such as a weak broadcast signal, or a poor quality consumer
VHS tape) can cause the system video hardware to lose a frame.
Do not use or invoke other applications concurrently while recording
video.
Do not move windows on the workstation display while recording video.
Check for the presence of any cron(1m) jobs which may activate while you
are recording video, and temporarily disable them.
Finally, you may want to ensure that rtnetd(1m) is enabled on your
system. This helps prevent network traffic from interfering with video
recording.
SCREEN RECORDING AND MONITOR REFRESH RATES
When you record movies from the screen using mediarecorder, the list of
available image rates for movie recording is typically dependent on the
refresh rate of the workstation monitor. To change the monitor refresh
rate, use the xscreen(1) (graphical, for O2 systems) or setmon(1)
(command line, all systems) utilities.
SCREEN RECORDING AND THE X ADVISOR
When mediarecorder records movie files from the screen, it can obtain
information from the X server about what is actually changing on the
screen. This is called the "X advisor".
With the X advisor, mediarecorder can know when nothing has changed on
screen, so it can avoid writing unnecessary screen data to disk. This
can improve the frame rate, and help screen recording files to occupy
less disk space. This is because the screen advisor helps mediarecorder
to capture the least amount of data necessary to accurately reproduce the
screen activity in the movie file.
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The X advisor is most useful for scenarios involving screen controls such
as buttons and menus, because very often, little of the screen changes.
There are situations in which the X advisor is less helpful. These
scenarios typically involve captures of 3D animations, where everything
in the window is updated on a frequent basis. In those situations, when
users want a full rate capture, it is best to turn off the X advisor.
This is because it uses CPU resources and can prevent the capture from
actually achieving full rate.
By default, the "Screen Recording (Windows, Buttons, Menus)" task uses
the screen advisor, and the "Screen Recording (Graphics, Rendering)"
tasks does not use the X advisor. To enable or disable the X advisor,
set or clear the "Use X advisor to optimize screen recording" checkbox in
the Custom Settings dialog, under the Tasks/Movie menu.
When you record from the screen using software, the X advisor is always
used as an intrinsic part of the recording process. Therefore, the
checkbox is disabled in the Custom Settings dialog.
COMMAND LINE OPTIONS
The following is a description of the options which may be specified on
the command line.
-media
Specify the initial media type for the tool at startup. Valid
choices are image, movie, or audio. Only one option may be
specified.
-source
Specify the initial signal source for the tool at startup, when
recording movies, or still images. Valid choices are video or
screen. Only one option may be specified. This option is ignored if
-media does not also appear on the command line.
-device devicename
Specify the initial hardware device name for the tool at startup.
If the device does not exist on the current system, or is not
specified, the default device will be used. Only one device name
may be specified. This option is ignored if -media does not also
appear on the command line.
The valid device names for movie capture from live video are:
vino Indy built-in (VINO) video
impact IMPACT Video or Octane Video boards
impactcomp IMPACT and Octane Compression, used alone or in
conjunction with IMPACT/Octane Video option boards
evo Octane Personal Video option board
ev1 Galileo, Indy Video, Indy Video 601, Indigo2 Video,
Indigo2 Video for IMPACT
cosmo Cosmo JPEG compression board, used in conjunction
with Galileo, Indy Video, Indy Video 601, Indigo2 Video, or
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Indigo2 Video for IMPACT option boards
mvp O2 built-in video hardware
The valid device names for movie capture from the screen are:
xlib Screen capture via the X Window System. This option uses
the system's built-in graphics hardware, and is available
regardless of system type or installed video hardware.
evo Screen capture via the Octane Personal Video option
board
cosmo Screen capture via the Cosmo JPEG compression
board, used in conjunction with Galileo, Indy Video, Indy Video
601, Indigo2 Video, or Indigo2 Video for IMPACT
mvp Screen capture via the O2 built-in video hardware
The valid device names for still image capture from live video are:
vino Indy built-in (VINO) video
impact IMPACT Video or Octane Video option boards
evo Octane Personal Video option board
ev1 Galileo, Indy Video, Indy Video 601, Indigo2 Video,
Indigo2 Video for IMPACT option boards
mvp O2 built-in video hardware
-jack jackname
Specify the initial jack name for the tool at startup, when
recording video or audio files. If the named jack does not exist,
or is not specified, the system default jack will be used. Only one
jack name may be specified. This option is ignored if -media does
not also appear on the command line, or if the source is something
other than video or audio.
The valid jack names for MVP video ("mvp") are:
camera
composite
yc
The valid jack names for Impact Video and Octane Video ("impact")
are:
node_dig_video_in_1
node_dig_video_in_2
node_dig_video_in_dl
The valid jack names for Impact Compression and Octane Compression
("impactcomp") are:
node_analog_video_in.Composite
node_analog_video_in.SVideo
Note that if both Impact Video and Impact Compression are installed,
or both Octane Video and Octane Compression are installed, you may
access both jack lists at once, from either the "impact" or
"impactcomp" devices.
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The valid jack names for the Octane Personal Video option board
("evo") are:
camera
Digital
yc
composite
The valid jack names for Indy Built-in Video ("vino") are:
indycam
yc
composite
The valid jack names for Galileo Video ("ev1") (with digital
breakout box) are:
yc1
yc2
yc3
composite1
composite2
composite3
yryby1
yryby2
parallel1
serial1
The valid jack names for Galileo Video ("ev1") (with IndyCam in
place of the digital breakout box) are:
indycam
yc1
yc2
yc3
composite1
composite2
composite3
yryby1
yryby2
The valid jack names for Indigo2 Video, and Indigo2 Video for IMPACT
("ev1") are:
indycam
composite1
yc1
composite2
The valid jack names for Indy Video ("ev1") are:
composite1
yc1
composite2
The valid jack names for Indy Video 601 ("ev1") are:
composite1
yc1
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composite2
parallel1
serial1
The valid jack names for the Cosmo Compression board ("cosmo") are
the same as those for the corresponding Galileo family product
installed on the system-Galileo Video, Indigo2 Video, Indigo2 Video
for IMPACT, Indy Video, or Indy Video 601.
The valid jack names for audio recording are the labels associated
with each of the audio input interfaces on the system. To learn
what the labels are for a given system, inspect the output of
audiopanel(1) when invoked with the -print option. Case is
important for audio jack names, and names containing spaces must be
enclosed in quotes.
-outputfile filename
Specify name of output file. The application will choose a default
name if this option is not specified.
-fixedfile
Fix the name of the output file, so it will not automatically
increment, and cannot be altered by the user.
-allowmenu menustring
This option allows you to restrict the media types and signal
sources which appear in the menus.
This option must be followed by a string containing groups of media
types and sources, separated by commas. No whitespace is allowed.
Media types and signal sources not explicitly specified on this list
will not appear in the menus.
The valid media types are image, movie, or audio. The valid signal
sources are video or screen. No signal source may be specified if
the media type is audio. The groups are separated by commas.
Multiple source names are separated with a plus sign.
This example will allow everything to appear on the menus:
-allowmenu movie=video+screen,image=video+screen,audio
This example allowing only the audio options on the menus. The user
will be able to record only audio files:
-allowmenu audio
This example allows only image capture from screen and movie capture
from video on the menus:
-allowmenu movie=video,image=screen
This example allows only movie capture from screen and movie capture
from live video on the menus:
-allowmenu movie=video+screen
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This example allows only movie capture from the screen on the menus:
-allowmenu movie=screen
-execstring shellcmdstring
This is a string to execute after any file is written to disk. The
sequence %s within the string will be substituted with name of the
captured file.
-noclipbin
This option is obsolete. It is maintained for compatibility with
previous versions of the application.
-screensel optionstring
This option controls the type and placement of the onscreen
selection rectangle used when performing screen captures. This
option is followed by a mandatory string containing any of the
following suboptions, separated by commas. No whitespace is
allowed:
method= [ adjustable | fullscreenntsc | fullscreenpal |
fullscreenntscsif | fullscreenpalsif | ntscfull | palfull ]
Type of screen selection. adjustable provides a user-resizable
frame. fullscreenntsc and fullscreenpal record the entire
workstation screen, resized to fit either an NTSC or a PAL sized
movie file, respectively. fullscreenntscsif and fullscreenpalsif
record the entire workstation screen, resized to fit an NTSC or PAL
SIF (half-sized) movie file, respectively. ntscfull and palfull
record an NTSC or PAL sized subrectangle of the workstation display
to a NTSC or PAL sized movie.
Not all screen selection options are available on all systems. In
particular, the ntscfull, and palfull options are available on O2,
Indy or Indigo2 with the Cosmo Compress option, and Octane with the
Octane Personal Video option. The fullscreenntsc and fullscreenpal
options are available on Indy and Indigo2 with the Cosmo Compress
option, or Octane with the Octane Personal Video option. The
fullscreenntscsif and fullscreenpalsif options are available only on
Octane with the Octane Personal Video option.
None of the screen selection options except adjustable are
recognized if the recording device is xlib. This is true regardless
of the workstation model or hardware options present.
Please note that when recording the entire workstation screen using
one of the video hardware options, typically only the top 960 lines
of the workstation display are captured. This is due to limitations
imposed by the video hardware option, not by the mediarecorder
application.
x= x
y= y
Origin of upper left corner of screen selection, in root window
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pixel units. The origin is not allowed if any of the fullscreen
selection methods are specified.
w= w
h= h
Width and height of screen selection, in pixels. The dimensions may
be specified only if the screen selection method is adjustable.
-delay n
This option sets the the time between when the record button is
pressed, and when recording actually begins to n seconds. This is
most useful for screen captures, as it gives the user time to remove
the mediarecorder application window from the display, or activate
menus, before recording starts.
The number of seconds is rounded up to the nearest value in the
following list: 3, 5, 10, 30, 60, or 300 seconds. These values
correspond to those found in the menus displayed by the graphical
interface.
-start
Begin recording immediately upon starting, without waiting for user
interaction.
-duration n
Causes recording to stop n seconds after it starts.
-exitdone
This option will cause mediarecorder to automatically exit after
recording is finished. The application will exit regardless of
whether it successfully records a media file, an error occurs while
recording, or recording is aborted by the user.
-movieoptions optionstring
Set the parameters for movie files. This option is followed by a
mandatory string containing any of the following suboptions,
separated by commas. No whitespace is allowed:
format= [ sgi | qt ]
File format for movie file. qt specifies Apple Computer's
QuickTime file format, and is the recommended file format. sgi
specifies the older Silicon Graphics movie file format. The SGI
format is supported primarily for backwards compatibility with
applications running on earlier releases of IRIX.
framesize= [ full | half | quarter ]
Size of video frame to record. This is ignored when recording
movies from the screen.
imgrate= n
This specifies not the actual frame rate, but an index into the
list of frame rates which are valid at the time of capture. The
first element of the list is zero, and is always the nominal
frame rate (29.97 for NTSC, 25 for PAL). Successively higher
numbers typically set integer dividends of the native frame rate
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(one-half nominal rate for n = 1, one-third nominal rate for n =
2, and so on). The nominal frame rate for most screen sources
is the monitor refresh rate, typically 60, 72, or 76 Hz. If the
index exceeds the end of the list of available frame rates, the
last entry (lowest rate available) is used.
compression= codecname
codecname is a string naming a compression codec. The allowable
codecs depend upon the movie format, and are found in the system
include file <dmedia/dm_image.h>.
spatialq= n
Spatial quality factor for the codec. This is a decimal number
between 0 and 1. Not all codecs support this feature, and it is
ignored if not supported.
temporalq= n
Temporal quality factor for the codec. This is a decimal number
between 0 and 1. Not all codecs support this feature, and it is
ignored if not supported.
keyframe= n
Key frame distance for the image track in the output movie file.
The movie file will be written with a key frame every n frames.
Not all codecs support this feature, and it is ignored if not
supported.
colorspace= [ xbgr | xrgb | yuv422 ]
Color space for image track of output movie file. xbgr
specifies SGI-compatible 8-bits per component RGB. xrgb
specifies QuickTime-compatible 8-bits per component RGB. yuv422
specifies YCbCr (YUV) color space with 4:2:2 color component
sampling. rgb and yuv are retained for compatibility with
earlier versions of the application, but their use is
deprecated. rgb is a synonym for xbgr, and yuv is a synonym for
yuv422.
interlacing= [ even | odd | none ]
Specifies field interlacing for output movie file. none
specifies a movie recorded as frames, with no video field
information. even specifies field encoding for PAL video, and
odd specifies field encoding for NTSC video. Typically, you
should only specify even or odd if you are recording JPEG,
Motion JPEG A, or uncompressed video.
audioenable= [ true | false ]
True if audio track should be recorded in movie file, False if
no audio track should be recording.
audrate= n
Sampling rate for movie audio track. The valid rates are found
in the system include file <dmedia/audio.h>.
audchannels= n
Number of channels in movie audio track. This may be 1, 2, or
4.
audwidth= n
Width of samples for movie audio track. This may be 8, 16, or
24.
droppedframeserror= [ true | false ]
Determines if recording should abort if any frames are dropped
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while recording.
screenadvisor= [ true | false ]
Determines if the X screen advisor should be used when recording
from the screen. Note that this option applies only when the
device used for screen recording is something other than "xlib".
When the device is "xlib" (the default), the screen advisor is
always used and this option is ignored. For more information,
see the section entitled "Screen Recording and the X Advisor"
elsewhere in this manual page. The default is false.
-imageoptions optionstring
Sets the parameters for image files. This option is followed by a
mandatory string containing any of the following suboptions,
separated by commas. No whitespace is allowed:
format= [ sgi | tiff | jfif | gif ]
File format for output image file.
framesize= [ full | half | quarter ]
Size of video frame to record. This is ignored when recording a
still image frame from the screen.
-audiooptions optionstring
Sets the parameters for audio files. This option is followed by a
mandatory string containing any of the following suboptions,
separated by commas. No whitespace is allowed:
format= [ aiff | aifc | wave ]
File format for output audio file.
audrate= n
Sampling rate for audio file. The valid rates are found in the
system include file <dmedia/audio.h>.
audchannels= n
Number of channels to record into audio file. This may be 1, 2,
or 4.
audwidth= n
Width of samples for audio file. This may be 8, 16, or 24.
EXAMPLES
To use mediarecorder to record a movie from live video, into a file
called TEMPMOVIE which your application will later access, do this:
mediarecorder-media movie -source video -allowmenu movie=video
-fixedfile -outputfile TEMPMOVIE
This will direct mediarecorder to record movies from live video and will
prevent changing from that mode. It will place the resultant movie file
in TEMPMOVIE. The user cannot change this name while mediarecorder is
running.
To use mediarecorder to record either still images or screen snapshots
into a file called TEMPIMAGE which your application will later access, do
this:
mediarecorder-media image -source screen -allowmenu image=video+screen
-fixedFile -outputfile TEMPIMAGE
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This will force screen snapshot mode and will allow the user to choose
between screen snapshot mode and video still frame mode. It will place
the resultant image file in TEMPIMAGE. The user cannot change this name
while mediarecorder is running.
To use mediarecorder to record QuickTime format movies from the IndyCam
using Cinepak compression do this:
mediarecorder-media movie -source video -jack indycam -movieoptions
format=qt,compression="Apple Compact Video"
This will direct mediarecorder to record movies from video, using the
IndyCam if it is connected to the system. The resulting movie is saved
in QuickTime movie format using Cinepak video compression. The user may
change both the recording mode (movie, image, audio) and the source
(video, screen) using mediarecorder's graphical interface. The name for
the resulting file will be generated by mediarecorder.
To use mediarecorder to record a movie file from the screen, then to run
the program "myprog" whenever it writes a file, do this:
mediarecorder-media movie -source screen -execstring "myprog %s"
This will direct mediarecorder to capture a movie from the screen, using
the default settings. Every time the user records a file, mediarecorder
will execute the program "myprog", passing it the name of the file the
user just captured.
To automatically record a 10-second movie file from the screen using the
X-based software facility, and have the application automatically exit
when it is finished, do this:
mediarecorder-media movie -source screen -delay 3 -duration 10 -start
-exitdone -screensel method=adjustable,x=10,y=10,w=259,h=341
-movieoptions format=qt,compression="Apple
Animation",colorspace=xrgb,interlacing=none,spatialq=0.8,temporalq=0.8,keyframe=24
To automatically record a 10-second NTSC video clip from the Octane or
IMPACT compression board, to a movie file using Motion JPEG A, and have
the application automatically exit when it is finished, do this:
mediarecorder-media movie -source video -device impactcomp -delay 3
-duration 10 -start -exitdone -movieoptions
format=qt,framesize=full,compression="Motion
JPEGA",colorspace=yuv422,interlacing=odd,spatialq=0.8,temporalq=0.8
To automatically record a still image from the workstation display, to a
SGI format image file, and have the application automatically exit when
done, do this:
mediarecorder-media image -source screen -delay 3 -start -exitdone
-imageoptions format=sgi -screensel
method=adjustable,x=15,y=15,w=243,h=591
To automatically record a 5 second AIFF audio clip from the default audio
input, and have the application exit automatically when done, try this:
mediarecorder-media audio -delay 3 -duration 5 -start -exitdone
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NOTES
Commonly, users wish to snap pictures or movies from a shell script, and
embed the results in a web page. You can do this with mediarecorder, as
it provides command line arguments to record files without human
interaction. However, if you do not want an onscreen graphical interface,
the vidtomem(1) or the dmrecord(1) utilities may be more suitable for
your needs.
mediarecorder does not create MPEG files. To create an MPEG file, record
a QuickTime movie (uncompressed video would be ideal if you have the disk
space) and use either the mediaconvert(1) graphical tool or the
dmconvert(1) utility to convert the QuickTime file into an MPEG movie.
When recording hardware JPEG-compressed movie files on an O2 system, from
Octane Compression /IMPACT Compression, or from the Cosmo Compress
board, choose SGI file format if you want a movie which is backwards-
compatible with IRIX 5.3 and 6.2 systems. When mediarecorder records
hardware JPEG files into QuickTime movies, it writes each frame as a pair
of video fields. The resulting file will not play on IRIX 6.2 and
earlier platforms.
To record motion JPEG files which are compatible with QuickTime on other
platforms, choose "QuickTime JPEG A" compression in the Movie Settings
Dialog, or specify "Motion JPEGA" as the compression choice in the
movieoptions options string from the command line. Keep in mind that
movies created using Motion JPEG A compression will not be playable with
releases of IRIX earlier than IRIX 6.5, except for IRIX 6.3 with the
appropriate patch set.
Though you may select video jacks from the menu built in to the
application, in order to adjust video parameters such as signal timing
(NTSC or PAL), hue, saturation, or video synchronization source, you must
use vcp(1), the Video Control Panel. Likewise, to choose audio inputs
for video and screen recording, or to adjust audio input levels, you must
use audiopanel(1), the Audio Control Panel.
mediarecorder requires overlay planes to run properly. Currently, all
graphics hardware with the exception of Onyx4 UltimateVision support
overlay planes by default. On Onyx4 UltimateVision, you must modify your
XF86Config(4) file under the devices section, and change:
Option "OpenGLOverlay" "off"
to:
Option "OpenGLOverlay" "on"
Once overlays have been enabled, you must restart the X server for the
changes to take effect.
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mediarecorder(1)mediarecorder(1)mediarecorder requires a root window with an OpenGL capable visual in
order to capture from the screen. If the root window is not OpenGL
capable, mediarecorder will generate an MVR GLX error when a capture is
attempted. The workaround is to manually specify the visual using the
-visid param in your Xservers file. Refer to the Xsgi(1) manpage for
more information.
FILES
$TMPDIR/.vkme*
Directories created by mediarecorder to hold temporary data during
movie capture. They are removed immediately after mediarecorder
writes the output movie file.
SEE ALSOmoviemaker(1), mediaplayer(1), audiopanel(1), vcp(1), soundtrack(1),
cdplayer(1), vidtomem(1), mediaconvert(1), dmconvert(1), dmrecord(1),
dmplay(1), xscreen(1), setmon(1)
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