Dashcam mode - Rotated image hint

kopidoo

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Just want to give a hint if you use your Yi upside down as a dashcam.
In that case you might need to use the rotated image. The image is rotated at the end of image processing, I mean after the light metering. In some situations (driving toward the sun and the sun is low) the road and the other vehicles will be underexposed. To help this issue I took a screenshot of the rotated image and tuned the AE table to match the road (see picture). Thanks to this the road is never underexposed, but the sky is more often burned, so to catch a meteorite is not possible. :)
I have also modified the average mode.
 

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gente

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...you mean the dashcam video is taken in normal mode (not rotated) and after processing and setting exposure the footage rotates , but the metering modes (especially from center mode) remains the same, so the underexposure from the bright sky switches now the road and the overexposure from darker road to the sky?
You tested that, i never have that idea of rotating video but not the AE table. Processing on cloudy days i noticed the darker lower part of video, so i decrease the gamma value by script. On sunny days sun behind never problems with exposure at the top and bottom.
So you use your modified center mode for dashcam using (not longer useful for normal footage) and average mode for normal videos?
In your settings for average mode the footage has to become brighter in the middle of video (more concentrating to the objects you focussing) when sun is low and makes the footage to dark because of overexposed sky, found specially in the shadow the center often is to dark so its also a good idea . I will testing your AE tables because it makes sense for me (or rotating via software).
Spot exposure for me is best for fotos, center for dashcam and average for filming without rotating.
very useful information @kopidoo :)
some sample footages?
 
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kopidoo

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I don't keep the records, only when something special happens. :(
So I can not show samples. The video what induced the whole thing was amazing, but the road was too dark! Similar to the attached photo (i've just googled)
s_____sample.jpg
 

gente

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I don't keep the records, only when something special happens. :(
So I can not show samples. The video what induced the whole thing was amazing, but the road was too dark! Similar to the attached photo (i've just googled)
View attachment 18042
I don't keep the records, only when something special happens. :(
So I can not show samples. The video what induced the whole thing was amazing, but the road was too dark! Similar to the attached photo (i've just googled)
View attachment 18042
..now with modified AEtable the exposure of footage is better in both modified modes?
Is your footage in attachment taken in rotating mode with normal AEtable?
You tested with new AEtable or is it only a speculation?
You take your modified center mode for dashcam and avarage mode for normal footage?
Thank you
 
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kopidoo

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The attached photo is not taken with the Yi! It is just a sample, and shows the original AE.
Both modified AE are better for me as the vanilla.
I have tested both, and are used daily.
Center is for dashcam, average is for normal footages.
I will reflash the vanilla fw to take some videos.
 

gente

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...i have tested today and you are right, rotating the picture in cam does not rotate autoexposure table. so the videos a little bit dark at cloudy days and against sun. on sunny days it doesn't matter. i have modified your center table a little bit so the footage becomes more brighter, added one line (normally the original,settings can be mirrored). The average settings are good for me. Now when using as dashcam i set to center, normal videos with average and fotos withbspot mode. i am thinking about to set average to original center values for processing the normal videos. i have also tested the resolution settings what bitrates are possible with my microsd. 2,3k is processing with at least 40 mbits without mistakes, the 1080p resolutions in 45mbits. So i set the highquality to 45/40mbits, normal to 35mbits and low to standard bitrates in the firmware. Start my coring/sharpness script at booting. and all is now working fine for me and my lens replaced and fixed xiaomi yi 23L.
Thanks for all the good inspiration in this forum.
Lg gente
 
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kopidoo

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I had no time to reflash the camera but I made a simple test by rotating the camera. The difference is here also visible.
I am happy when there is at leat one person who think it is good for something :)
Are your scripts posted here in the forum somewhere? I want to check it out.
 

gente

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great sample for the behavior of the AEtable rotating the camera and there is no solution also rotating the picture for dashcam processing! But with your new center values we can prevent of them. Do you know if gopros or other cams have the same behavior?
before i often think about the missing brightness on road using xiaomi as dashcam. but now everything is clear to me, you have gave the crucial tip. now i have to be careful switching the right exposure mode.
we need a dashcam switching script, rotating and setting the right mode, like the resolution mode switcher here described in forum.
 

vili

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you should use upside down settings in the app. So even the sensor readout and rolling shutter direction would be the opposite.
I hope the AE table will be correct. Somebody will test it..
 

gente

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I test it, you have to change the values of the center metering mode upside down if you want to use in AEtable of firmware. Using average mode you do not have to change anything because all values are the same in this exposure mode. This behavior is Only when you rotate camera and switch it in the app.
 

kudykam

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Hi guys do you know how can I make the video stay rotated? When I turn the app off it rotates back to its originál position
 
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