Security video recording

[Tomcat]

I'm currently using a VCR and video camera for a security application. I'm looking at switching to a DVR. I can't seem to find recording times for what I'm trying to do. If the camera/DVR will record at 30 frames per sec. (FPS)using MPEG4 or whatever the DVR uses. How many hours can I record on say a 160 gig hard drive. Or are there other factors I need to know?

[Ken King (Premo)]

After reading some reviews for portable recording units you should be able to record about 2 hours per gig, so with a 160 gig drive that would be about 320 hours +/- 10%.

[Tomcat]

Originally Posted by Ken King

After reading some reviews for portable recording units you should be able to record about 2 hours per gig, so with a 160 gig drive that would be about 320 hours +/- 10%.

Thanks Ken, I tried looking up specs for different applications but couldn't find anything that made any sense. Is it the MPEG4 that's the determining factor? Or the frames per second or both? See how easily I get confused.

[Gwydion]

Ken's estimations seem incredibly high for any decent recording. Everything contributes to the size of the file. Resolution, fps, colours, sound.

For example, perhaps you can get 2 hours per gb at 480x600 8 bit colour. But 1024x1280 at millions of colour you might get an hours worth for 4gbs.

I know from my video editing that 28.7 fps at "high" resolution 10 minutes is about 200 mbs.

If you can tell us the make and model of the camera we can get you a much more accurate answer.

[Tomcat]

Originally Posted by Gwydion

If you can tell us the make and model of the camera we can get you a much more accurate answer.

I'm trying to compare before buying. That's why I'm asking the questions. One system says 30FPS, another says 120FPS, quality is normally low, med and high. I found this on one site but it seems to be for their DVR so I don't know if I can plug in numbers to compare?

80G Hard disk @ 7 fames per second @ Normal Quality
(80*1024*1024 K byte) / ( 7*15*60*60 ) = 222 Hours

[pcjohnnyb (Premo)]

Originally Posted by Gwydion

Ken's estimations seem incredibly high for any decent recording. Everything contributes to the size of the file. Resolution, fps, colours, sound.

For example, perhaps you can get 2 hours per gb at 480x600 8 bit colour. But 1024x1280 at millions of colour you might get an hours worth for 4gbs.

I know from my video editing that 28.7 fps at "high" resolution 10 minutes is about 200 mbs.

If you can tell us the make and model of the camera we can get you a much more accurate answer.

And unless you absolutely must have it, I would not record sound. Not recording a sound track should save you substantial space in the long run

[itsbob (Premo)]

Originally Posted by Tomcat

I'm currently using a VCR and video camera for a security application. I'm looking at switching to a DVR. I can't seem to find recording times for what I'm trying to do. If the camera/DVR will record at 30 frames per sec. (FPS)using MPEG4 or whatever the DVR uses. How many hours can I record on say a 160 gig hard drive. Or are there other factors I need to know?

I'd say you need to know the quality of the frame.

ie.. is taking 640X480?

Or is it HD qualilty video?

Frames per second is fine, but you need to know the size of the individual frames.

[itsbob (Premo)]

Originally Posted by Gwydion

Ken's estimations seem incredibly high for any decent recording. Everything contributes to the size of the file. Resolution, fps, colours, sound.

For example, perhaps you can get 2 hours per gb at 480x600 8 bit colour. But 1024x1280 at millions of colour you might get an hours worth for 4gbs.

I know from my video editing that 28.7 fps at "high" resolution 10 minutes is about 200 mbs.

If you can tell us the make and model of the camera we can get you a much more accurate answer.

Originally Posted by Tomcat

I'm currently using a VCR and video camera for a security application. I'm looking at switching to a DVR. I can't seem to find recording times for what I'm trying to do. If the camera/DVR will record at 30 frames per sec. (FPS)using MPEG4 or whatever the DVR uses. How many hours can I record on say a 160 gig hard drive. Or are there other factors I need to know?

if you are expecting to have something you can use in a Court of Law, the higher the Res and more FPS the better ... HD are cheap storage, but then you must also do specific this when transferring files after recording

[Tomcat]

This is the spec sheet from the one that gave the formula above

ITEM DESCRIPTION NOTE
Video Format NTSC / PAL
Operation System STAND ALONE
Camera Input Channel 4 channel Composite BNC
Video Output Channel
2 channel Composite BNC
USB 2.0 Port
NTSC 120 frames 4 x 30 frames
Display Frame Rate
PAL 100 frames 4 x 25 frames
Recording Frame Rate NTSC Max 30 fps (Quad) Quad Mode
(Quad) PAL Max.25 fps (Quad) Quad Mode
NTSC
Each Channel =
30 / Number of Source(frames)
Max. 30 frames
Recording Frame Rate (Each Channel)
(Each Mode)
PAL
Each Channel =
25/ Number of Source(frames)
Max. 25 frames
(Each Channel)
Record Modes
Continuous, Schedule, Motion
Triggered , Sensor Triggered
Display
NTSC 720 x 480
PAL 720 x 576
Resolution
Record
NTSC 320 x 112, 640 x 224
PAL 320 x 136, 640 x 272
Quad 640 x 224 (total)
Each 640 x 224
Video Compression Format
(Each Channel)
Modified Motion-JPEG
(12-20K bytes/frame)
Low :12K Byte
Normal :15K Byte
High : 20K Byte
HDD Support 200G Byte ATA -100 Interface
Estimated Record Length
80G Hard disk @ 7 fames per second @ Normal Quality
(80*1024*1024 K byte) / ( 7*15*60*60 ) = 222 Hours
Method Time, Date, Event
Search
Full Screen YES
Sensor, Alarm
4 Inputs (Normally Open / Normally Closed)
1 Output (Relay contacts rated 2A @28VDC )
Camera Signal Loss Alarm
PTZ RS-485
Dimensions Length 315mm * Width 224mm * Height 52mm