Optimal capture resolution?

sgn · Post by **sgn** » Thu Apr 26, 2007 1:27 pm

I've been running ZM for years. Been capturing at half PAL resolution, as I never figured out the actual ouput resolution of my cameras.

I have thirteen of these cameras:
http://www.altram.com.pl/Katalogi/Videotronic/fs6_e.pdf

and two of these:
http://www.altram.com.pl/Katalogi/Videotronic/fs7_e.pdf

(-6012P and -7012P)

What is the optimal capture resolution? I know the cameras have X TV-lines (vertical resolution), but what is the optimal horizontal resolution?

robi · Post by **robi** » Thu Apr 26, 2007 1:41 pm

Cameras have For 330 TV lines resolution and 460 TV lines resolution. Best match if the number of lines equals with the height of the captured picture. Bigger height is useless.

However in PAL, capturing above 384x288 produces interlacing.
So the recommended settings would be 320x240 for the first type you mentioned, and 384x288 for the second one.

You can however run all in 384x288 to have them equal and look good.

sgn · Post by **sgn** » Mon May 07, 2007 3:06 pm

OK... I have a couple of these too, it seems:
http://www.sanyosecurity.com/np-item/p_ ... 6585p.html

What would be the best capture resolution on these?

robi · Post by **robi** » Mon May 07, 2007 3:29 pm

it says 520 TV lines...
Any picture height above this number is useless. 384x288 for this too.

sgn · Post by **sgn** » Mon May 07, 2007 7:35 pm

OK. Great, thanks

.

Is 384x288 "compatible" with the actual ouput from the cameras, though? It won't cause any distortion like if you don't do a linear resize on both axis?

The reason I'm asking is that stored images aren't exactly impressive in quality. Might be JPEG-"noise", though. Perhaps ZM will come with PNG-support as a lossless option. Requires more space, but higher quality might come in handy to some.

sgn · Post by **sgn** » Mon May 07, 2007 7:47 pm

One last thing, which palette should I be using? Using RGB24 now, it works, but might be the cause of the crappy images? Seeing the other thread about the "lines" due to shmem, where the images were far better?

sgn · Post by **sgn** » Fri May 25, 2007 12:16 pm

And what is the ACTUAL output resolution (in h*w pixels) of these three cameras?

robi · Post by **robi** » Fri May 25, 2007 12:23 pm

PAL aspect ratio is 4:3, as long as your capture resolution Width:Height is 4:3 scale, no distortion will occur.

Analog cameras have lines, not pixels. Pixels are in digital format, eg only after capture.

jameswilson · Post by **jameswilson** » Fri May 25, 2007 6:06 pm

sgn wrote:One last thing, which palette should I be using? Using RGB24 now, it works, but might be the cause of the crappy images? Seeing the other thread about the "lines" due to shmem, where the images were far better?

Use 100 in the quality thats pretty lossless, but lossless images IMO would be a huge waste of space, much better to get a better source and PAL/NTSC isnt it

sgn · Post by **sgn** » Sat Jun 02, 2007 5:35 pm

Well, 100% image quality helped a bit, but let's say I just for kicks want to store the events in the maximum possible resolution without actually upscaling them, which resolution should I configure ZM to use for the specific three cameras?

jameswilson · Post by **jameswilson** » Sun Jun 03, 2007 9:18 pm

as above if you go above half res on your standard )ie pall is 288) then you will get interlace issues. So dont go any higher, or go higher and accept it. Or use ip cams that dont have this issue (ie axis) then you can do multi megapixel.

eug · Post by **eug** » Sun Jun 10, 2007 12:15 am

jameswilson wrote:as above if you go above half res on your standard )ie pall is 288) then you will get interlace issues. So dont go any higher, or go higher and accept it. Or use ip cams that dont have this issue (ie axis) then you can do multi megapixel.

How do the apps that come with tuner cards give a good picture at full res? Do they do software deinterlacing, or use the hardware differently?

I'm running my cameras at 352x288 at the moment, but there are some cameras that could greatly benefit from 704x576, at which i get interlacing issues.

I'm using a Kodicom 8800, which I thought was capable of 8x 704x576...

Is there a way to do software deinterlacing? I should have enough cpu cycles to spare for one or two cameras.

thanks

eug · Post by **eug** » Sun Jun 10, 2007 12:32 am

eug wrote:
jameswilson wrote:as above if you go above half res on your standard )ie pall is 288) then you will get interlace issues. So dont go any higher, or go higher and accept it. Or use ip cams that dont have this issue (ie axis) then you can do multi megapixel.
How do the apps that come with tuner cards give a good picture at full res? Do they do software deinterlacing, or use the hardware differently?

mmm.. looks like the video card does the deinterlacing, at least in a pc with a decent graphics card.

It'd be great if ZM could do s/w deinterlacing one day...

edit: looks like deinterlacing is being looked at already.. here's to hoping everything falls into place eventually!