How to increase JPG quality via autoexec.ash?

huhu2207

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Hi all,

As we all know, Xiaomi generates JPG files only around 4MB, it "zipped" too much and it looks bad especially when the zooming the pictures.



I found this command in the autoexec command list:

t cal [OPTION] VALUE...
Supported options:
-3a: AAA control
-3a_test: AAA stat regression test
-sc: Scene mode control
-de: Digital effect control
-ae: AE info
-me: Manual exposure
-raw: raw capture
-rawenc: raw encode with manual main window width/heigh
-ituner: ituner tool
-mgr: Calibration manager CLI tool
-fpn: FPN tool
-vnc: Vignette tool
-vnc_spec: for warp by spec
-task: WARP decay ratio en/disable
-warp: WARP tool
-warp_spec: for warp by spec
-ca: CA tool
-gen_ca: Gen CA tool
-jqlt: Set capture jpg quality
-bmp: Set dump bmp enalbe
-usb: Set remove/insert sdcard

... and then I tried "t cal -jqlt 100" but it seems not working at all !

So, can I change the quality like "writeb" and "writew" command and change the settings just like changing the video bitrate (like this, in #24: https://dashcamtalk.com/forum/threads/yi-hacked-resolution-2304x1296-30fps-35mbits.11589/page-2) ?
 
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By default the quality is set to 95%, so it's possible that on 100% you'll not notice much difference. Yes it's possible to do it with writeb command, I'll post later if you want to try.
 
By default the quality is set to 95%, so it's possible that on 100% you'll not notice much difference. Yes it's possible to do it with writeb command, I'll post later if you want to try.

I tried this yesterday, but I deleted the whole things in the sdcard including theautoexec script by mistake so I forgot what exactly the code was. It might be:

t cal -jqlt 100
sleep 5
t app key shutter

...then it will increase the size to 5~7MB per JPG picture and it seemed better. In fact this command works, but it's not "permanent". The camera will take one picture after boot up. Then if I press the shutter key, the output file size will revert to the original settings.
 
Settings for capture in manual mode are kept in RTOSFS and override any changes done with autoexec script each time when you press the shutter button. So we can't change JPEG quality with the "t" command or with altering any memory bytes.
 
Settings for capture in manual mode are kept in RTOSFS and override any changes done with autoexec script each time when you press the shutter button. So we can't change JPEG quality with the "t" command or with altering any memory bytes.

Oh...what a pity...
But we still can use the RAW to edit and then generate photos with a high quality~
 
Settings for capture in manual mode are kept in RTOSFS and override any changes done with autoexec script each time when you press the shutter button. So we can't change JPEG quality with the "t" command or with altering any memory bytes.
Emm, well...is it possible to modify the firmware to increase the quality?
 
Hi, can you also improve exposure time and iso settings for take night shot like this? (taken with GoPro Hero 4 silver)
 
Looks like we can do that. Max exposure time is 8s. Took it out from the HDR script from nutsey:

Code:
sleep 8
#SET ISO TO 100
t ia2 -ae exp 100 0 0
sleep 1
#1 == 7.9s; 50 == 6.1s; 100 = 4.6s
t ia2 -ae still_shutter 1
 
Best way to use the script is to set the camera in Timelapse photo mode at least 10s interval and let it run. For a night timelapse I would also disable all leds in the app.
 
Looks like we can do that. Max exposure time is 8s. Took it out from the HDR script from nutsey:

Code:
sleep 8
#SET ISO TO 100
t ia2 -ae exp 100 0 0
sleep 1
#1 == 7.9s; 50 == 6.1s; 100 = 4.6s
t ia2 -ae still_shutter 1

Okay, I will have a try...
 
ok thanks, i'll try next days, only a question, to improve this script i just need to put it on the autoexe file in the cmera' SD card and it wil work automaticcally or should I'set it somethig trought the mobile App? setting will get lost after the first shot? Thak you for all!
 
Hi, can you also improve exposure time and iso settings for take night shot like this? (taken with GoPro Hero 4 silver)
Best way to use the script is to set the camera in Timelapse photo mode at least 10s interval and let it run. For a night timelapse I would also disable all leds in the app.

Emm... well, I'm in Shenzhen China, where it's full of dust in the air and unnecessary light at night, so that means it might be impossible here to capture a nice night timelapse.
But I will have a test later for capturing the images in the city center.
 
Emm... well, I'm in Shenzhen China, where it's full of dust in the air and unnecessary light at night, so that means it might be impossible here to capture a nice night timelapse.
But I will have a test later for capturing the images in the city center.
I live in Italian coutryside, my Yi Camera should arrive this week, i'll post the result as son I can
 
Just unzip and put the autoexec file in the root of the SD card. Set timelapse 10s+ interval mode from the camera App.
I tested it and it works. Good job! :)
But it does need a stabilizer or the images will be terrible.
 
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