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The
Review
Captured Video
mode is only useable when the video sequence capture is
finished and the mark on the
Write
checkbox is off. When the
Review Camera
button is
pressed the FastViewer-USB application inquires the camera about the start of each
image in the camera memory. The Preview Display area is blank during this search since
the USB is carrying non-visual information. When this process is complete the images in
the memory can be previewed without actually transferring them all to the host computer.
The Review mode is able to show only 640x480 images. If the image size is set to larger
than 640x480 you will only see the upper left part of the image that fits in the 640x480
window or a decimated version that fits in the window. (This is limited by the USB 2.0
interface we are using).
Figure 17, The Review Captured Video controls
The
Display-Digital Gain
can be used again to enhance the preview window images
. If it
is set to x1 then you are looking at the upper 8 bits of the ten bit pixel (9:2), if it is set to x2
you are looking at the middle 8 bits of the ten bit pixel (8:1), and if it is set to x4 you are
looking at the lower eight bits (7:0). The image data is not clipped or saturated, so you may
again see a kind of striping effect, which is normal.
The
'Go'
button will begin displaying images from the current image pointer. The direction
is initially forward in time, but the
'<'
and
'>'
buttons can change this direction.
The
'Stop'
button will stop the automatic display of the next image in sequence. The slider
and the
'<'
and
'>'
buttons can be used to step the display.
The button marked
'|<'
will move the image pointer to the first (earliest) image in camera
memory. The one marked
'>|'
will move to the last image in camera memory. The button
marked
'<'
will step to the previous image AND set the play direction to backwards. The
button marked '
>
' will step to the next image AND set the play direction to forwards. The
play speed is fixed by the performance of your computer and the USB interface, or 20
frames per second which ever is slower.
The
'To Trigger'
button will position the image pointer on the
trigger frame
(i.e. first frame
acquired after the trigger assertion) and display it, if it is in the camera memory. If you set
