GIT2P 90 firmware mod

user777

Member
Joined
Jan 29, 2019
Messages
44
Reaction score
6
Location
Finland
Country
Finland
Dash Cam
GitUp Git2P
To begin with let me say that contrary to the photos, I do like the video IQ of the stock FW. Yes, viewed at 100% it shares a lot of the bad qualities of the photos (oversharpening, truckloads of noise reduction, etc) but on the other hand a video is not meant to be scrutinised like a still image.
When played back you get a lovely tonal character, nicely saturated colours, smooth motion with very little/no jello effects... Yes the bitrate is rather low, yes you can see the noise reduction smothering details on trees and road, but on the whole the videos are very nice indeed.

Now, there is no question if the modded FW's videos are better or not. They are.
But they are also far less "impressive" than the stock ones at least on stock settings.

Using a stock clip as a guide I tried many settings to get as close to the original "punchiness" as I could. I took about 20 clips and a fair amount of side by side viewing but here's my issues with the modded FW video image quality:

1. Most serious issue: pronounced rolling shutter (jello effect). On the test clips I hadn't seen anything as there were no vibrations, but on the motorcycle two days ago I noticed some serious jello effects especially around the edges of the video (trees, power lines, hills, sky etc) On the stock FW I had no issue but all those clips were done at 1080p30, so it may be just wrong settings. I'll run some tests again and report. If this doesn't go away though it is potentially a deal breaker.

2. Second serious issue: highlight clipping. One thing that was immediately obvious on the modded videos was that cloud details were mostly blown. The stock video kept all the cloud details nicely preferring to underexpose the whole scene a bit rather than lose the details. On the modded videos, the scene was slightly brighter but you got big blank/white patches on the sky where grey clouds should be. Maybe @hc_1982 modified the curves a bit resulting in this highlight clipping?

2. Rather soft footage. Normal sharpness is a bit low IMHO. High sharpness solves the issue nicely but could go even a bit further.

3. Low color saturation and contrast on stock settings. While the color saturation can be nicely fixed with the "Colorful" setting, the lowish contrast is not so easily changed. The high contrast setting is simply too aggressive. Of course this is a moot point as everything can be tweaked in post.

Eventually I settled on the following settings for the best look out of the box:
- Sharpness: HIGH
- Contrast: LOW
- Colours: COLORFUL
- Bitrate: High

Below you can see a side by side comparison of the stock clip (Left) vs the best mod clip (Right).
Overall IQ:
46084

Immediately apparent that the modded clip has a better tonal character and equally pleasing colours. Again the eagerness to blow the highlights (look at the sky on the right) but this can be fixed by setting EV to -1/3. I didn't set it as I felt it wasn't such a huge issue here, but YMMV.

Details @ 100%:
46085


46086

Details on the modded clip are visibly better, especially on the trees and fine details, but I think the difference is not as pronounced as with the photos. I guess we are bumping up the limits of what this little camera can do?

All in all the modded FW's videos seem to come out very nice indeed, BUT I reserve final judgement due to the jello issues.

Full clips for you to download.
Stock FW clip. All settings standard.

Modded FW clip. Best settings found as above.
 
OP
H

hc_1982

Member
Joined
Aug 19, 2018
Messages
95
Reaction score
63
Country
Ukraine
Great review, @user777 !
Gamma curves have been changed indeed, same as several other settings related to Auto Exposure. As I working with mod when have free time (mostly at night), it lacks some testing in daylight conditions, so overblown highlights are quite possible with default settings. But make sure you have latest version of mod installed (released 8 days ago), as it has some adjustments for AE. Also note, that video file recorded with Git2P has YUV format set to TV standard limited range, while actually it is recorded as Full range. Players are mostly ignoring top highlights and darkest shadows and clip it. It should be overriden manually in post, or special effect could be used with mod - Black&White, which transforms YUV from Full Range into Limited Range. In latest version of mod, effect Sepia have been changed in the same way but with increased saturation (crossover between B&W and Colorful). So, I would suggest testing it (with contrast Normal) to overcome highlight clipping and make colors stronger.

As I use my camera mostly indoors, I was trying to adjust it for such low-light conditions - original contrast was too high, image too dark and blurred due to high noise reduction settings, so lot of settings have been tweaked for it. Current settings are still not optimal, and I'm keep experimenting with it. Although, sensor used in Git2P is not the best one for such low light shooting, so now I have switched to Git3 and Ezviz S2 action cameras, which have the same chip inside and quite close firmwares, so it is relatively easy to reuse some findings from Git2P with them, and vice versa, but better sensors for low light conditions.

Sharpening in stock firmware works in following way - edges are detected in image, and one side of it is drawn with darker color, and external one with white. Strength of it could be adjusted with menu options. As for me, it looks too oversharped and unnatural, especially when faces or grass are shot, so I have changed it such way that Low option turns off sharpening completely (as for me, it has kind of analog/film soft look); Normal option disables external white edge, and High works like something between Normal and Low in stock. Another downside of stock sharpening is noise/garbage it introduces: any pixel which has some difference in brightness compared to neighbors is treated as valid object for sharpening, so it becomes darker and white contour is drawn around it. As result, stock firmware has to have high NR settings to blur everything first and then draw dark and white borders around these blurred areas. The higher resolution of image (still/video) and high ISO make it very noticeable. For this reason, I would suggest using sharpness Low, in case ISO is higher than 100-200 for stills in mod, and Normal/Low for video in low light.

As I have mentioned earlier, rolling shutter issue is inevitable with this camera for high resolution video modes, and should be approximately on par with stock for >= 1440p and 1080p60 (and 1080p50 in mod), with exception to 1080p30, which should have same rolling shutter as 1440p, but better details compared to stock one. Also 1080p60 should have same rolling shutter as 1080p30/60 in stock, while still better details compared to them. 1296p30 is upscaled 1080p60 in stock, while it is downscaled 1440p30 in mod (same as 1080p30). 1440p and 2160p (1620p in mod) should be more or less similar (but with lower NR, less sharpening and higher bitrate in mod)
 

nekodrugi

New Member
Joined
Apr 18, 2016
Messages
6
Reaction score
2
Country
United States
Many thanks for the firmware mod!

I applied the version from 2019-04-20 (git2p.8.zip) and it really
improves detail in JPGs! I rarely do videos so I didn't check that
this time.

This mod really improves things. It is only that the colors and
metering doesn't look optimal to me.

I did a limited test outside having also a "serious camera" (Panasonic
Fz1000) and old Xiaomi Yi for comparison.

In default settings it does seem that Git2P needs -1/3EV (or maybe
-2/3EV).

In Git2P I changed metering to "average" (icon with 5 dots). I think
it does improve metering a bit for me, but it still needs compensation
(at least -1/3EV).

I tried color-->colorful and that is not doing what I need.
Color-->vivid does look bit better.

What makes things different is setting white balance to cloudy or
daylight (instead of auto). This is surprising to me! I had plenty of
light outside and auto white balance should be daylight (or cloudy).
But obviously it is not doing that. Also, metering seems to change to
better with WB-->daylight or WB-->cloudy.


However the question of what is the most truthful color (by comparing
photos to a "serious camera") is very difficult. Comparing such images
it does suggest that the default or auto options (with maybe -1/3EV
compensation) are not that wrong. Auto options just make me think that
bit of something is missing. I can't help feeling that Color-->vivid
or WB-->daylight or WB-->cloudy make more pleasing images. And yes,
the old Xiaomi Yi does dial a lot on "vividness" scale, but I still
find those images pleasing.


I had also experiments with fine focusing the camera (by tightening screws that hold the lens base):
Code:
https://dashcamtalk.com/forum/threads/git2p-fine-focusing-by-lens-screws.39683/
 
OP
H

hc_1982

Member
Joined
Aug 19, 2018
Messages
95
Reaction score
63
Country
Ukraine
Hello @nekodrugi
Thanks for your feedback! I guess, it would be possible to improve it a bit, in the same way it was done for git3 fw mod. I will apply some changes and post new mod for testing here soon.
 

Hondu

New Member
Joined
Jul 3, 2017
Messages
26
Reaction score
5
Country
United Kingdom
Thanks for the hard work. Quick question is this mod suitable for use on my motor cycle and helmet.. bearing in mind the extra vibrations etc. If so can you recommend what settings to use. I don't have much time to test it myself unfortunately.

Regards
 
OP
H

hc_1982

Member
Joined
Aug 19, 2018
Messages
95
Reaction score
63
Country
Ukraine
Hello @Hondu, I believe, 1080p60/50 with default settings should be reasonable in such conditions.
 

nekodrugi

New Member
Joined
Apr 18, 2016
Messages
6
Reaction score
2
Country
United States
Lack of time combined with bad weather (plus I am weary to "test" this
indoors in the evening) prohibits me from testing GIT2PFW.mod.test1.zip.


However I noticed something strange in JPGs.
There is a strange "mesh" overlayed onto JPGs.
The mesh is regular quadratic, about 300x100 pixels.

Here is best image to show it.
By mistake I had cap on and if you extremely stretch levels you can see it.
Here is original JPG and edited (high levels stretch and then 4x shrink, I also inserted this edited image in the post below): google drive dir
2019_0714_135320_219-stretch_levels_4x_shrink.jpg


This is not only some darker/brighter pixels arrayed in a quadratic mesh. There is loss of detail at mesh position.
If I were to guess what this is: probably artifact of some fast low-res rectification.
I don't have time to check RAW images, or original firmware of camera.
Does anybody know what this is?
 
OP
H

hc_1982

Member
Joined
Aug 19, 2018
Messages
95
Reaction score
63
Country
Ukraine
Hi @nekodrugi
I have been able to replicate issue you have described with the same setup. This "mesh" is present only in jpeg, while raws are free of it, neither I see it in modded git3 photos. So, it is caused by internal image processing. Finally, after some additional checks and tests it has been localized. RAW files produced with git2p have 4624x3488 dimensions, while JPEGs are 4608x3456. Difference is 16 columns and 32 lines, and it matches with "mesh" you have discovered, and which have been just jpeg encoder resize artifact. I have changed resolution of processed image to match jpeg ones by cropping it a bit, and now it seems to be ok.
But now RAW file dimensions are not the same as in stock firmware, so settings for raw processing software should be changed too, e.g. following line should be added to raw2dng config file:
Code:
31850496, 0, 4608, 3456, 7, 9216, 16, 6, Git2P_M
Please check updated mod fw and let me know about your findings.

 

nekodrugi

New Member
Joined
Apr 18, 2016
Messages
6
Reaction score
2
Country
United States
Thanks hc_1982, that was quick!
What you describe sounds very plausible.
Did you change metering and colors in git2pfw_mod_test2.zip (compared to git2p.8.zip)?


I just have time to post a test I did today:
Code:
https://drive.google.com/open?id=1kBNchudGaa76NvoXSdYqqWW6Mr8M-q4T

Git2P was running git2pfw_mod_test2.zip. Metering was "average" (icon with 5 dots).

Image number N (2019_07_17-N-*.jpg)
01 - Panasonic Lx100 (big sensor camera)
02 - Git2P WB:auto 0EV
03 - Git2P WB:auto -1/3EV
04 - Git2P WB:auto -2/3EV
05 - Git2P WB:auto -1EV
06 - Git2P WB:daylight 0EV
07 - Git2P WB:daylight -1/3EV
08 - Git2P WB:daylight -2/3EV
09 - Git2P WB:daylight -1EV
10 - Panasonic Lx100 (big sensor camera) 
11 - Xiaomi Yi
Quick take:
- if something is important always dump raw image, just in case
- seems that "rectangular mesh" is gone
- WB:auto and 0EV seems close to what big sensor does
- colors still not perfect (see red), but how much should one expect from a small sensor? tough question.
- I still feel that Git2P should beat Xiaomi Yi by wider margin concerning level of details (it does, but I would expect much more given difference in FOV)


I am still pondering about fine level of details.
To be continued at later point...
 
OP
H

hc_1982

Member
Joined
Aug 19, 2018
Messages
95
Reaction score
63
Country
Ukraine
Hello @nekodrugi, thanks for your test report!
I guess, you can improve details by tuning lens focus more precisely (turn it to infinity just for few degrees), although left side of your shots seems to be out of focus too much as lens holder is not perfectly aligned still. Also, I would suggest to use ISO: Auto in such bright light conditions, as it will use ISO50 with lower noise level and less noise reduction (please have a look at this test photo taken handheld through not very clean glass of window and notice readability of car plates and level of noise across the sky). But note, that my git2p sample has quite good alignment of lens holder out of the box, while I had 2 git3 samples and one of them had almost 1/4 of the left side out of focus, and another one has similar issues on the right side, although not so severe and acceptable for 1080p video, but still not very good for photo and I was not able to fix it at the moment.
As for me, photo taken with Yi is processed with noise reduction filter too strong and most of fine details are gone and only contours remain (check the trees and tiles on roofs, which looks like filled with solid color regions, color patches or some kind of painting, and it seems to be "feature" of Amba based cameras).
Gamma curves, noise reduction, some AE and color correction settings has been changed compared to git2p.8 mod fw, and similar to ones used in current test mod for GIT3. In my opinion, colors are too "vivid" now and noise level is too high, while sharpening should be stronger a bit, so more work needs to be done to improve image quality, but even in ideal case, colors won't be perfect in any way, due to limited capabilities of this small camera and lack of knowledge/expertise from my side in this field, so feel free to leave your suggestions about color or other adjustments for improving image quality.
 

Similar threads


Top