Setting the best quality and filesize for my camera

[Mtz]

First I want to say that "best" is not the real and correct word when is about video. So asking for the real best is most of the time useless, so you can use another words, like "better".
Just think when you had the DVD movies and you are thinking the best for you was an original DVD9. Now we have Blu-Ray, like Avatar. Tomorrow... 4K?

I think quality the recordings are because of: lens, light. compression algorithm or the user settings.
On my PC I have two sample videos from the same camera, but different firmwares and when looking at their parameters the values are different, depending on use.


Original screenshot size from my PC is here.

Always keep in mind this:
A higher resolution is not a higher quality, is just a resolution. HD is High Definition, not GHQ (Guraranteed High Quality) When is about the video you should think to the quantizer in this way:
- you have 1000 bytes for 1000 pixels. this is OK, you will see every pixel OK
- you have 1000 bytes for 2000 pixels. this is not OK because every pixel is trying to steal the byte from the neighborhood >> macroblocks, pixelation
- you have 2000 bytes for 1000 pixels. this is not OK because every pixel is over another one and not adding any value
Good quantizers are between 20 and 30, the smaller the better, but under 17 is almost useless.

So back on your dashcam: if you want smaller bitrate, and smaller size for videos use 720p.
But this will not guarantee you will not have macroblock because this is depending also on the compression algorithm, like profile used or CABAC, and your lens module quality.

So if you have the choice to use 1080p or 720p make the right decision.

The player used in the screenshots is the free Media Player Classic Home Cinema and the information about video files are provided by the free MediaInfo.

enjoy,
Mtz

Edit: The one with 17mbps is a hacked firmware which have a increased value from 7mbps to 17. But this hack can cause overheat and for sure big filesizes.

 

[jimjones]

Thanks for the info.

 

[Pebo]

I recently bought and received the Pittasoft BlackVue DR500GW-HD and believe I have the video settings set for my liking but I'm not 100% sure. My issues are that my recordings don't seem to be the same quality of the ones for this system that I've seen on the internet. Some You Tube videos that I've seen on the BlackVue DR500GW-DW show that the BlackVue software allows a quick zoom allowing for good quality images of a passing vehicles license plate. I'm actually quite pleased with the actual video but when I try to zoom in on a license plate, most of them are unreadable with pixels scattered and mixed. I believe the higher the resolution the better for the video quality and I understand the lower the resolution, the longer the recording time on the SD card. Currently, I have the setting set at "Full HD (1020x1080) @30fps" and normal compression. The other Image Quality available settings are:
-Full HD (1020x1080) @15fps
-HD (1280x720) @ 30fps
-HD (1280x720) @ 15fps
-D1 (720x480) @ 30fps
Compression Normal or High

Additionally, I've read other posts where users report that their recorders (other brands) show they are recording at a higher resolution, but they claim that what is actually recorded is of a lower resolution than the recorder indicates. I took one of my recordings and looked at the properties (see the attachment .jpg) and it shows that my resolution is what I have it set for 1020x1080 @29fps.

The settings I have set, am I recording at the best quality? Secondly, checking the "properties" of the recording file, is this the proper and accurate way to verify that the recorder is recording at the indicated settings?

 

[DashCamMan]

Hi Pebo,

You are recording at 1920x1080p 30fps (not 1020) and also using normal compression. That is the best image you are going to get out of this camera. The 29fps and 7400kpbs bit rate is slightly below what this camera does (7500kpbs, 30fps) so perhaps you lost a few frames in that video. Not a big deal.

Overall, the only way quality will be better is if Pittasoft decides to release a firmware with a variable bitrate. Quality improves much more at over 10,000kpbs.