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<h1 align="right"> <b><i><font face="Arial, Helvetica, sans-serif"><font size="+1">Video 
  capture on the 320 and 540</font></font></i></b></h1>

<div align="right">
<h1>
<b><font face="Arial, Helvetica, sans-serif"><font size="+1">visual workstations</font></font></b></h1></div>

<hr width="100%">
<ul>
<li>
<font face="Arial, Helvetica, sans-serif"><a href="#Quicktime">QuickTime</a></font></li>

<li>
<font face="Arial, Helvetica, sans-serif"><a href="#VFW">Video for Windows</a></font></li>

<li>
<font face="Arial, Helvetica, sans-serif"><a href="#dmSDK">Media SDK</a></font></li>
</ul>
<a name="Quicktime"></a><b><u><font face="Arial, Helvetica, sans-serif"><font size="+1">QuickTime</font></font></u></b>
<p><font face="Arial, Helvetica, sans-serif">The 320 and 540 visual workstations
ship with a capture component for QuickTime (QT).&nbsp;&nbsp; This component,
known as the Video Digitizer, allows capture of video and audio into a
standard QT file.&nbsp; In this section we provide a list of applications
that make use of this component, and list some of the features exposed
through this component.&nbsp; A list of known limitations and bugs is provided
at the end.</font>
</p><p><b><font face="Arial, Helvetica, sans-serif">Supported Applications</font></b>
</p><ul>
<li>
<font face="Arial, Helvetica, sans-serif">Any application written for the
QT Video Digitizer API or the Sequence Grabber API would work with the
supplied capture component.&nbsp; Adobe Premiere or <a href="ftp://ftp.apple.com/Quicktime/developers/hacktv.zip">HackTV</a>
are examples of such applications.</font></li>
</ul>
<b><font face="Arial, Helvetica, sans-serif">Formats and Features</font></b>
<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Video timing</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The QT capture component
supports both PAL and NTSC timings.&nbsp;&nbsp; For PAL a maximum of 576
lines can be captured, and for NTSC a maximum of 486 lines can be captured.&nbsp;
The timing is user selectable through the standard QT video control panel.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Square vs. Non-square Pixels</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The QT capture component
supports capture of square pixels and CCIR-601 non-square pixels.&nbsp;&nbsp;
Two different Video Digitizers are provided for this functionality.&nbsp;
For PAL, the square digitizer supports a maximum of 768 pixels across,
and the non-square digitizer supports a maximum of 720 pixels across.&nbsp;
For NTSC, the square digitizer supports a maximum of 640 pixels across,
and the non-square digitizer supports a maximum of 720 pixels across.&nbsp;
The square or non-square Video Digitizer are user selectable through the
QT video control panel.&nbsp; PAL and NTSC timings can be specified for
each digitizer.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Scaling</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">Choosing a Video
Digitizer (square or non-square) and the timing determine the size of a
video frame.&nbsp; This frame can then be scaled to various sizes.&nbsp;&nbsp;
The QT capture component supports any size that the hardware can scale
to.&nbsp;&nbsp; Most of the popular scaled sizes, 1/2, 1/4, etc., will
work.&nbsp; The scaling size should be user selectable through the application
being used.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Pixel Formats &amp; Compressed
Formats</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The capture component
allows&nbsp; video to be captured into a number of input formats.&nbsp;&nbsp;
A list of all supported formats, both compressed and uncompressed, can
be viewed in the QT video control panel.&nbsp;&nbsp; Although the user
can capture video into any of the listed formats, performance will vary
depending on the format selected.&nbsp; For uncompressed real-time capture,
we encourage users to capture in: SGI 2vuy, SGI ABGR, SGI BGRA or SGI RAW
(Greyscale only).&nbsp;&nbsp; For compressed real-time capture, we encourage
users to capture in the following formats: SGI Photo JPEG and SGI Motion
JPEG.&nbsp; The JPEG compressors do not use any hardware acceleration and
are CPU intensive.&nbsp; Depending on the quality selected, two processors
may be necessary.&nbsp; Quality settings greater than 80 will result in
dropped frames!&nbsp; The SGI prefix in the formats listed does not imply
that these formats are proprietary;&nbsp;&nbsp; it is inserted&nbsp; to
indicate accelerated capture support for these formats.&nbsp;&nbsp; The
format to capture video in can be specified through the QT video control
panel.</font></blockquote>

<ul>
  <font face="Arial, Helvetica, sans-serif">Source Jack</font> 
  <p><font face="Arial, Helvetica, sans-serif">Users can capture from the Composte 
    input jack or the S-Video input jack.&nbsp; On a 540 with a SD1100 Option 
    card, the user can also capture from one of two Serial Digital input jacks.</font> 
  </p>
  <li> <font face="Arial, Helvetica, sans-serif">Color Settings</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The Brightness, Contrast,
Saturation, &amp; Hue controls are for the current selected input jack.&nbsp;
These control only apply to the analog input jacks.&nbsp;&nbsp; These controls
are disabled when using a Serial Digital input jack.&nbsp; The settings
for these controls can be adjusted through the QT video control panel.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">2 Channel capture</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The capture component
supports simultaneous capture of 2 channels of video.</font></blockquote>
<b><font face="Arial, Helvetica, sans-serif">III. Caveats and Known Bugs</font></b>
<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Screen playback performance</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">Playback of files recorded 
  in SGI 2vuy and SGI 5551 is not real-time under QT 3.0.2 (or earlier versions).&nbsp; 
  QT 3.0.2 version does not use hardware acceleration to display these formats 
  on the screen.&nbsp; QT 4.0 or higher will fix this problem.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">File size limit</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">QT 3.0.2 imposes a file 
  size limit of 2 GB.&nbsp; The QT 4.0 supports file sizes well over 50 GB!</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">QT specific bugs</font></li>
</ul>

<blockquote> 
  <ol>
    <li> <font face="Arial, Helvetica, sans-serif">The preview window will lock 
      up inside Premiere if another window is dragged on top of it.&nbsp; QT 4.0 
      will fix this problem.</font></li>
    <li> <font face="Arial, Helvetica, sans-serif">After capturing a clip inside 
      Premiere, if one goes to modify the capture settings, an access violation 
      results.&nbsp; QT 4.0 will fix this problem will fix this problem.</font></li>
  </ol>
</blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Premiere specific bugs</font></li>
</ul>

<blockquote>
<blockquote><font face="Arial, Helvetica, sans-serif">For Adobe Premiere
specific issues, please consult the <a href="ftp://ftp.sgi.com/sgi/320-540/premfaq.shtml">Premiere FAQ</a>.</font></blockquote>
</blockquote>
<b><font face="Arial, Helvetica, sans-serif">IV. Free Software</font></b>
<blockquote>
<ol>
    <li> <font face="Arial, Helvetica, sans-serif"><a href="ftp://ftp.sgi.com/sgi/320-540/examples/qtcap/bin/qtcap.zip">QTcap</a>: 
      This application was written in-house by Kevin Meier and <a href="mailto:sumo@esd.sgi.com">Sumit 
      Chawla</a>.&nbsp; The application can preview data to the screen or capture 
      data to disk.&nbsp; All the features mentioned above can be accessed through 
      this application.&nbsp; Source code for this application will be available 
      through our developer program.</font></li>

<li>
<font face="Arial, Helvetica, sans-serif"><a href="ftp://ftp.apple.com/Quicktime/developers/hacktv.zip">HackTV</a>:
This is a free capture application available at the Apple QT website.&nbsp;
Most of&nbsp; the features mentioned above can be accessed through this
application.</font></li>
</ol>
</blockquote>
<a name="VFW"></a><b><u><font face="Arial, Helvetica, sans-serif"><font size="+1">Video
for Windows</font></font></u></b>
<p><b><font face="Arial, Helvetica, sans-serif">I. Supported Applications</font></b>
</p><ul>
<li>
<font face="Arial, Helvetica, sans-serif">Video for Windows Applications</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The 320 and 540 ship
with a capture component for the Microsoft Video for Windows (VFW) API,
so any capture applications written for the VFW API can be used to capture
video to memory or disk.&nbsp; These include Adobe Premiere, Speedrazor,
Ulead MediaStudio Pro, and many others.&nbsp; Another example is Microsoft's
VidCap (vidcap32.exe), which ships with the 320/540 visual workstations.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">DirectShow Applications</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The 320 and 540 also
support video capturing via the DirectShow API.&nbsp;&nbsp; The DirectShow
API is a superset of the VFW API, such that the same VFW capture component
can be used by both VFW applications and DirectShow applications.&nbsp;
One example of a DirectShow application is AmCap, which is a sample program
included in the Microsoft DirectX Media SDK.&nbsp; (Click <a href="http://www.microsoft.com/directx/default.asp">here</a>
to download the DirectX Media SDK).</font></blockquote>
<b><font face="Arial, Helvetica, sans-serif">II. Formats and Features</font></b>
<ul>
<li>
<font face="Arial, Helvetica, sans-serif">VFW Capture Settings Dialog Box</font></li>
</ul>

<center><img src="Video%20Capture%20on%20the%20320_540_soubory/vfwcap.jpg" alt="vfwcap.jpg (46389 bytes)" width="510" height="431"></center>

<p><br>
<br>&nbsp;
</p><blockquote><font face="Arial, Helvetica, sans-serif">The SGI VFW Capture
Settings Dialog can be launched from the "Video Format", the "Video Input",
or the "Video Display" commands, which are exposed by all VFW capture applications.&nbsp;
For instance, VidCap exposes them through the Options menu.</font></blockquote>

<ul><font face="Arial, Helvetica, sans-serif">Source Jack</font></ul>

<blockquote><font face="Arial, Helvetica, sans-serif">Users can capture
from the Composte input jack or the S-Video input jack.&nbsp; On a 540
with a SD1100 Option card, the user can also capture from one of two Serial
Digital input jacks</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Source Timing</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The VFW capture component
can capture from either NTSC sources or PAL sources. However, the capture
component does not auto-detect the timing of the incoming video; the user
is responsible for selecting the corresponding timing in the Capture Settings
dialog box.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Color Settings</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The Brightness, Contrast,
Saturation, &amp; Hue controls are for the current selected input jack.&nbsp;
They are identical to the controls exposed in the SGI Video Control Panel;
they are duplicated here for the user's convenience.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Square vs. Non-square Pixels</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The user can select
whether to capture square pixels or CCIR-601 non-square pixels.&nbsp; The
conversion is done via a hardware Mitchell filter.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Image Size</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The supported capture
sizes are listed below:</font>
<br>&nbsp;</blockquote>

<blockquote>&nbsp;
<center><table width="70%" cellpadding="2" border="">
<tbody><tr>
<td colspan="2" width="32%">
<center><font face="Arial">NTSC</font></center>
</td>

<td colspan="2" width="34%">
<center><font face="Arial">PAL</font></center>
</td>
</tr>

<tr>
<td width="16%" align="CENTER"><font face="Arial">Non-Square Pixels</font></td>

<td width="16%" align="CENTER"><font face="Arial">Square Pixels</font></td>

<td width="17%" align="CENTER"><font face="Arial">Non-Square Pixels</font></td>

<td width="17%" align="CENTER"><font face="Arial">Square Pixels</font></td>
</tr>

<tr>
<td width="16%" align="CENTER">
<div style="line-height: normal"><font face="Arial">720x480</font></div>
</td>

<td width="16%" align="CENTER"><font face="Arial">640x480</font></td>

<td width="17%" align="CENTER"><font face="Arial">720x576</font></td>

<td width="17%" align="CENTER"><font face="Arial">768x576</font></td>
</tr>

<tr>
<td width="16%" align="CENTER"><font face="Arial">360x240</font></td>

<td width="16%" align="CENTER"><font face="Arial">320x240</font></td>

<td width="17%" align="CENTER"><font face="Arial">360x288</font></td>

<td width="17%" align="CENTER"><font face="Arial">384x288</font></td>
</tr>

<tr>
<td width="16%" align="CENTER"><font face="Arial">180x120</font></td>

<td width="16%" align="CENTER"><font face="Arial">160x120</font></td>

<td width="17%" align="CENTER"><font face="Arial">180x144</font></td>

<td width="17%" align="CENTER"><font face="Arial">192x144</font></td>
</tr>

<tr>
<td width="16%" align="CENTER"><font face="Arial">88x60</font></td>

<td width="16%" align="CENTER"><font face="Arial">80x60</font></td>

<td width="17%" align="CENTER"><font face="Arial">88x72</font></td>

<td width="17%" align="CENTER"><font face="Arial">96x72</font></td>
</tr>
</tbody></table></center>

<p><font face="Arial, Helvetica, sans-serif">For NTSC, the capture region
starts at line 23 and ends at line 263 for Field 1.&nbsp; For Field 2,
it starts at line 285 and ends at line 525.&nbsp; For PAL, the capture
region starts at line 23 and ends at line 311 for Field 1, and for field
2, it starts at line 336 and ends at line 624.&nbsp; For sizes less than
the full active region, the video is down-scaled per field, then interleaved.&nbsp;
Work is under way to support capturing 486 and 487 lines for NTSC.</font>
</p><p><font face="Arial, Helvetica, sans-serif">The capture component currently
does not support arbitrary capture sizes.&nbsp; If the user needs to change
the size of the captured video, he/she needs to use a video editing application
to edit the captured file.</font></p></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Pixel Formats &amp; Compressed
Formats</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">The supported capture
formats are:</font>
<br>&nbsp;
<br>&nbsp;
<center><table width="70%" border="">
<tbody><tr>
<td width="25%" align="CENTER">&nbsp;</td>

<td width="25%" align="CENTER"><font face="Arial">FOURCC Code</font></td>

<td width="25%" align="CENTER"><font face="Arial">Real Time</font></td>

<td width="25%" align="CENTER"><font face="Arial">Output via VFW</font></td>
</tr>

<tr>
<td width="25%" align="CENTER"><font face="Arial">32-bit BGRA</font></td>

<td width="25%" align="CENTER"><font face="Arial">'DIB '</font></td>

<td width="25%" align="CENTER"><font face="Arial">Y</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>
</tr>

<tr>
<td width="25%" align="CENTER"><font face="Arial">16-bit BGR</font></td>

<td width="25%" align="CENTER"><font face="Arial">'DIB '</font></td>

<td width="25%" align="CENTER"><font face="Arial">Y</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>
</tr>

<tr>
<td width="25%" align="CENTER"><font face="Arial">16-bit UYVY</font></td>

<td width="25%" align="CENTER"><font face="Arial">'UYVY'</font></td>

<td width="25%" align="CENTER"><font face="Arial">Y</font></td>

<td width="25%" align="CENTER"><font face="Arial">Y</font></td>
</tr>

<tr>
<td width="25%" align="CENTER"><font face="Arial">8-bit Greyscale</font></td>

<td width="25%" align="CENTER"><font face="Arial">'DIB '</font></td>

<td width="25%" align="CENTER"><font face="Arial">Y</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>
</tr>

<tr>
<td width="25%" align="CENTER"><font face="Arial">Motion JPEG</font></td>

<td width="25%" align="CENTER"><font face="Arial">'MJPG'</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>
</tr>

<tr>
<td width="25%" align="CENTER"><font face="Arial">Photo JPEG</font></td>

<td width="25%" align="CENTER"><font face="Arial">'JPEG'</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>

<td width="25%" align="CENTER"><font face="Arial">N</font></td>
</tr>
</tbody></table></center>

<p><font face="Arial, Helvetica, sans-serif">Here, "real time" refers to
consistently being able to capture full active region on a disk with appropriated
performance without frame drops (for more information on disk bandwidth,
click <a href="ftp://ftp.sgi.com/sgi/320-540/uncompressed.shtml">here</a>).&nbsp; The JPEG formats are
compressed using software codecs; their performance are much more dependent
on other running processes on the system.</font>
</p><p><font face="Arial, Helvetica, sans-serif">The 16-bit UYVY files can
be played back to video output; for more information, see the <a href="ftp://ftp.sgi.com/sgi/320-540/vidplay.shtml#VFW">video
playback</a> section.</font></p></blockquote>
<b><font face="Arial, Helvetica, sans-serif">III. Caveats and Known Bugs</font></b>
<ul>
<li>
<font face="Arial, Helvetica, sans-serif">VFW Capture Takes Two Channels</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">One important caveat
is that when any VFW capture application is running, no other video capture
application can be running, including those applications that use QuickTime.&nbsp;
The same is not true of QuickTime capture applications; two QuickTime capture
applications can be running simultaneously.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Preview vs. Overlay</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">VFW allows two modes
for displaying to the computer screen: preview &amp; overlay.&nbsp; For
the SGI capture component, the preview mode reflects what is being captured,
i.e. the same pixel formats, image size, etc., but it does not preview
in real time.&nbsp; The overlay mode does display the video in real time,
but it displays uncompressed 32-bit BGRA regardless of the capture settings.&nbsp;
For example, if the user sets the pixel format to 8-bit Greyscale, then
in preview mode the video display would be greyscale, but in overlay mode
the display would still be in color.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Interleaved Frames vs. Non-interleaved
Fields</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">Currently, the VFW
capture component only captures in interleaved frames.&nbsp; This can cause
visible artifacts on the computer screen, particularly for smaller capture
sizes.&nbsp; (For more details, see <a href="http://reality.sgi.com/cpirazzi/lg/fields/fields.html">this
section of the Lurker's Guide</a>).&nbsp; Work is currently in progress
to support capturing in non-interleaved fields to avoid this problem.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">NetMeeting Access Violation</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">Microsoft NetMeeting
needs the VFW capture size to be at most 160x120; otherwise, NetMeeting
would cause an access violation.&nbsp; We believe this to be a NetMeeting
bug since the problem has been reproduced on a third-party video capture
card as well.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">RealPlayer G2 Does Not Play Some
Movies Properly</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">For some movies,
the free RealPlayer G2 displays video as black when the "Optimized Video"
option is turned on.&nbsp; The workaround is to turn off Optimized Video.&nbsp;
This problem does not appear on RealPlayer 5.0, which is bundled with the
320/540.</font></blockquote>

<ul>
<li>
<font face="Arial, Helvetica, sans-serif">Premiere-specific Bugs</font></li>
</ul>

<blockquote><font face="Arial, Helvetica, sans-serif">For Adobe Premiere
specific issues, please consult the <a href="ftp://ftp.sgi.com/sgi/320-540/premfaq.shtml">Premiere FAQ</a>.</font>
<br>&nbsp;</blockquote>
<a name="dmSDK"></a><b><u><font face="Arial, Helvetica, sans-serif"><font size="+1">SGI
Digital Media SDK</font></font></u></b>
<blockquote><font face="Arial, Helvetica, sans-serif">We also have a Media
SDK for developers interested in adapting their applications specifically
for the 320/540.&nbsp; Please see http://www.sgi.com/developers/nt/sdk/dmsdk.html
for more information.</font>
<br>&nbsp;</blockquote>
<font face="Arial, Helvetica, sans-serif"><a href="ftp://ftp.sgi.com/sgi/320-540/index.shtml">Back To
Index</a></font>
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