jpg image light level modifications

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jpg image light level modifications

Post by ian.potter » 2017-11-24T19:40:11-07:00

Hi I am new to this product (Imagemagick) and this forum.
We currently use Photoshop to modify jpg images, basically playing with lighting levels to make a daytime photo look like a nigh time photo. Imagine you took a photo of your living room at home in the day time, then you reduced the "exposure" so it looked like night time and turned on the wall lights, table lights, pendant etc. That is what we do in Photoshop, 1 image can take days to do properly.
I want to speed up this process, can this be done in Imagemagick?

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Re: jpg image light level modifications

Post by fmw42 » 2017-11-24T19:54:34-07:00

I think you will need to provide more detail of what exactly you do in Photoshop and an input and output image.

Do you do things like drawing to create masks or dodge/burn with brush strokes or painting? If so, those are hard to do in imagemagick, since ImageMagick is not a GUI based system. It is command line driven, which makes it good for scripting.

But other hands off processing can be done in imagemagick and scripts built on imagemagick.

If it takes a full day using Photoshop, then you likely are doing things customized to each image. If that is the case, then ImageMagick is not likely going to make it faster.

If you have things you do the same to every image and need to process lots of images, then ImageMagick is a good tool for that.

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Re: jpg image light level modifications

Post by Bonzo » 2017-11-25T02:07:35-07:00

Reducing the "exposure" is straight forward. As fmw42 says there is no GUI; so how do you know where the lights are, what is the "pool" of light supposed to look like - square on, at an angle - how big and what colour etc.

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Re: jpg image light level modifications

Post by snibgo » 2017-11-25T02:25:32-07:00

Shadows are totally different when a room is lit from a window, compare to artificial lighting. Why not re-photograph the room?

An advanced AI system might take the daylight photo and construct a 3D model of the room, which can be lit any way you want, and ray-traced. But this is not trivial.
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