JVC VN-685U User Manual
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JPEG
B
Quality/Size
For specifying the rate control mode and target file size for JPEG.
When
AVFS1B to AVFS7B is selected, the quantization table during JPEG
encoding will be maintained and the file size will increase/decrease
according to the input signals. Stipulated values will be displayed in the Size
field. When recording JPEG data to a recorder with a limited storage
capacity, note that the maximum recording time may vary as the file size
fluctuates under this setting.
When
AAFSB is selected, encoding is performed such that the target file size
is the average size of multiple JPEG images. You can enter the target size in
the [Size] field.
[Size field setting range for VGA: 10KB to 100KB (Only when setting
AAFSB)]
[Size field setting range for QVGA: 3KB to 33KB (Only when setting
AAFSB)]
MPEG4
C
Bitrate
For setting the MPEG4 encoding bit rate.
[Setting range:64kbps to 8000kbps]
D
Bitrate Control
For selecting whether to set the MPEG4 rate control mode to CBR (Constant
Bit Rate) or VBR (Variable Bit Rate).
CBR
: Encoding is performed at a fixed bit rate regardless of the
condition of the input video signals. Enables easy forecast of the
bit rate.
VBR
: Changes the bit rate according to the condition of the input
video signals. Picture quality is stable, but forecast of the bit rate
is difficult.
E
FPS
For setting the MPEG4 frame rate.
[Setting range:1 fps, 7.5 fps, 10 fps, 15 fps, 25 fps, 30 fps]
F
I Frame Interval
For setting the I-frame interval. MPEG4 starts encoding from the I-frame.
Shortening the interval stabilizes the picture quality even when there are
rapid changes in the video image. However, the picture quality for images
with little change will deteriorate. In addition, when multicast packet loss
occurs, the time interval required to restore the image is shorter.
[Setting value:30, 60, 90, 120, 150]
G
Priority
For selecting whether to assign priority to the frame rate or picture quality
during MPEG4 encoding.
FPS
: Assigns priority to frame rate. Select this setting to enable
smooth monitoring of motion images.
Quality
: Prioritizes image quality.
Memo
:
● Valid when [Bitrate Control] D is ACBRB. When a very small bit rate is set
for the frame rate or frame size,
ACBRB or AVBRB will become the lowest
images and a difference will appear in the frame rate.
AQualityB which
skips frames will be able to realize small bit rates better than
AFPSB.