# Wandb gray scale image does not show the black color

**URL:** <https://community.wandb.ai/t/wandb-gray-scale-image-does-not-show-the-black-color/3932>\
**Category:** W&B Help\
**Tags:** wandb\
**Created:** [February 22, 2023, 6:51pm UTC](https://community.wandb.ai/t/wandb-gray-scale-image-does-not-show-the-black-color/3932 "2023-02-22T18:51:40Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![hyuntae93](https://avatars.discourse-cdn.com/v4/letter/h/ee59a6/32.png) [@hyuntae93](https://community.wandb.ai/u/hyuntae93)\
**Post date:** [February 22, 2023, 6:51pm UTC](https://community.wandb.ai/t/wandb-gray-scale-image-does-not-show-the-black-color/3932/1 "2023-02-22T18:51:40Z")

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![스크린샷 2023-02-23 03.48.05](https://us1.discourse-cdn.com/flex020/uploads/wandb/original/2X/a/ae1cc805b9214fb901fa6efe4ffadea5217cd402.jpeg)

I’m trying to make a mask from the first image.  
The mask consists of 0, 1 values and it has only one channel.  
To check the image on Wandb, I used `wandb.Image(image)`.  
But the mask image do not show the black color, instead it describe the 0 value as gray color like second image.

How can I make the 0 value to the black color?

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**Author:** ![mohammadbakir](https://avatars.discourse-cdn.com/v4/letter/m/a9a28c/32.png) [@mohammadbakir](https://community.wandb.ai/u/mohammadbakir)\
**Post date:** [February 23, 2023, 6:57pm UTC](https://community.wandb.ai/t/wandb-gray-scale-image-does-not-show-the-black-color/3932/2 "2023-02-23T18:57:46Z")

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Hi @hyuntae93 , happy to help. I checked your segmentation project and it appears you did not assign masks to your images. Wandb will log the exact image provided to wandb.Image call. Were you intending to create [overlays over the images](https://docs.wandb.ai/guides/track/log/media#image-overlays)?

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**Author:** ![hyuntae93](https://avatars.discourse-cdn.com/v4/letter/h/ee59a6/32.png) [@hyuntae93](https://community.wandb.ai/u/hyuntae93)\
**Post date:** [February 24, 2023, 7:27am UTC](https://community.wandb.ai/t/wandb-gray-scale-image-does-not-show-the-black-color/3932/3 "2023-02-24T07:27:07Z")

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Thanks for help @mohammadbakir .

I didn’t intend to overlay the mask over the image.  
I intended to multiply the mask to the image for segmentation the image as the foreground and the background.

The third image is the result of `mask \times input ` and the last image is the result of `(1-mask) \times input`.

Then is the gray color intended result for the 0 value? instead of black color?

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**Author:** ![system](https://us1.discourse-cdn.com/flex020/uploads/wandb/original/1X/366b649231631dbab896843020da0056074ac79d.png) [@system](https://community.wandb.ai/u/system)\
**Post date:** [April 25, 2023, 7:27am UTC](https://community.wandb.ai/t/wandb-gray-scale-image-does-not-show-the-black-color/3932/4 "2023-04-25T07:27:36Z")

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