Jpeg File Format Sent Out By Vn-E4 - JVC VN-E4U - 4 Channel Network Encoder Api Manual

1. Acquiring JPEG from VN-E4 via HTTP _

1.5. JPEG File Format Sent Out by VN-E4

JPEG files sent out by VN-E4 are compliant with JFIF and consist of the following.
FFD8 Start Code
FFE0 Application Segment
FFFE Comment Segment
FFC0 SOF Frame Information
FFDB DQT Quantization Table
FFC4 DHT Huffman Table
FFDA Data Start Segment
FFD9 End Code
The following information is stored in the comment segment. Each item has a fixed length.
Item
Version Information
File Size
Width
Height
Model Name
Invert Flag
Time Stamp
Alarm Information
Camera ID
Motion Detect Setting
Motion Detect Result
Reserved
Reserved
Synchronization Time Stamp
Video Signal Format
Input Channel
Picture Quality
Rate Control
Target Size
Quantization Scale
Firmware Version Information 12
Item names and values, excluding the version information that does not include =, are stored in the following format.
Item names Space
Example: When width=640, the 13-byte area will be written as follows.
w i d t
Size Example
9 JVC V1.0
18 size = 123456
13 width = 640
14 height = 480
18 type = VN-E4
12 Stores inversion
information set at VN-E4.
70 timestamp =
20050214130509123JST
13 alarm = 00000001
50 camera = input01
11 motion = 1
7 md = 1
17
32
26 sync_timestamp =
1FDC5A34
20 format = NTSCU
7 ch = 1
9 intp = 0
16 size_cntl = VFS
19 size = 23456
14 q_scale = 45
ver = 01.00
= Space
Defined fixed length by each item.
h =
1.5. JPEG File Format Sent Out by VN-E4
Description
Indicates the version of information stored in the comment segment
The number of bytes of the JPEG file.
Width of JPEG.
Height of JPEG.
Name of model that created the JPEG.
Specified as reverse=1 in the case of a vertical inversion.
Indicates the time at which JPEG is created. This is made up of the
year/month/day, hour/minute/second, millisecond and timezone code.
Indicates the alarm input status when the JPEG is created in a 4-byte
binary value. (Not ASCII code.) 4 alarm inputs are assigned to 4 bits
from the LSB. For example, value is alarm = 00000001when changes
occur with alarm input 1, alarm = 00000008 when changes occur with
alarm input 4, and alarm = 00000009 when changes occur with alarm
inputs 1 and 4.
Stores camera information set at VN-E4. Character code is Shift-JIS
when information is stored in Japanese.
Specified as 1 when the motion detect feature is ON.
Specified as 1 if motion is detected at the time when JPEG is created.
Indicates the 8 kHz counter value in a 4-byte binary value. (Not
ASCII code.) This can be used when synchronizing with audio.
Indicates the input video signal. Stated as NTSCJ for NTSC in Japan,
and NTSCU for other NTSC formats. Stated as PAL for PAL format.
Indicates the signal source among the 4 inputs of VN-E4.
Stated as 1 when this is set to field interpolation at VN-E4, and 0
when this is set to frame processing.
Describes the mode of rate control for JPEG. VFS (VariableFileSize),
AFS (AverageFileSize) or CFS (ConstantFileSize).
Target size of rate control.
Indicates the quantization scale. Up to 3 digits.
Indicates version of the firmware that is used to create JPEG.
values 0x00
6 4 0 0x00 0x00
9