Image transformations in Supabase

Introduction

Image transformations let you change pictures automatically, like resizing or cropping, without changing the original file.

You want to show smaller images on a website to load faster.

You need to crop a photo to fit a specific shape or size.

You want to add effects like blur or grayscale to images.

You want to optimize images for different devices like phones or tablets.

You want to create thumbnails from large images automatically.

Syntax

Supabase

https://your-project.supabase.co/storage/v1/object/public/bucket-name/image.jpg?transform=resize,width:300,height:200&transform=crop,width:100,height:100

Use query parameters after the image URL to apply transformations.

Multiple transformations can be chained by repeating the 'transform' parameter.

Examples

This resizes the image to 150 pixels wide and 150 pixels tall.

Supabase

https://your-project.supabase.co/storage/v1/object/public/photos/cat.jpg?transform=resize,width:150,height:150

This crops the image to 100x100 pixels.

Supabase

https://your-project.supabase.co/storage/v1/object/public/photos/dog.jpg?transform=crop,width:100,height:100

This converts the image to black and white.

Supabase

https://your-project.supabase.co/storage/v1/object/public/photos/bird.jpg?transform=grayscale

This resizes the image width to 300 pixels and then applies a blur effect with radius 5.

Supabase

https://your-project.supabase.co/storage/v1/object/public/photos/flower.jpg?transform=resize,width:300&transform=blur,radius:5

Sample Program

This URL resizes the image to 200x200 pixels, then crops a 100x100 section.

Supabase

https://your-project.supabase.co/storage/v1/object/public/images/sample.jpg?transform=resize,width:200,height:200&transform=crop,width:100,height:100

Important Notes

Always keep the original image safe; transformations do not change the stored file.

Use transformations to improve website speed by loading smaller images.

Check Supabase documentation for all available transformation options.

Summary

Image transformations change how images look without changing the original file.

Use URL query parameters to resize, crop, or add effects.

They help make images fit better and load faster on websites and apps.

Practice

1. What is the main purpose of image transformations in Supabase storage?

easy

A. To change how images look without modifying the original file

B. To permanently delete the original image after editing

C. To convert images into text files

D. To upload images faster by compressing them automatically

Solution

1. Step 1: Understand image transformation concept

   Image transformations modify the appearance of images dynamically without changing the original stored file.

2. Step 2: Identify the purpose in Supabase

   Supabase uses transformations to resize, crop, or add effects on the fly, keeping the original image intact.

3. Final Answer:

   To change how images look without modifying the original file -> Option A

4. Quick Check:

   Image transformations = change appearance only [OK]

Hint: Image transformations do not alter the original file [OK]

Common Mistakes:

• Thinking transformations delete or overwrite original images
• Confusing transformations with file format conversion
• Assuming transformations speed up upload automatically

2. Which URL query parameter correctly resizes an image to 300 pixels wide in Supabase?

easy

A. ?size=300

B. ?resize=300

C. ?width=300

D. ?w=300

Solution

1. Step 1: Recall Supabase image resize syntax

   Supabase uses the parameter w to specify width in pixels for resizing images.

2. Step 2: Match correct parameter

   The correct query parameter to resize width to 300 pixels is ?w=300.

3. Final Answer:

   ?w=300 -> Option D

4. Quick Check:

   Resize width = ?w=number [OK]

Hint: Use ?w= for width resizing in Supabase URLs [OK]

Common Mistakes:

• Using ?width= or ?resize= which are invalid
• Confusing size with width parameter
• Omitting the question mark in URL

3. What will be the result of accessing the URL https://example.supabase.co/storage/v1/object/public/images/photo.jpg?w=200&h=100&fit=crop?

medium

A. The image will be resized to 200x100 pixels and cropped to fit exactly

B. The image will be resized to 200x100 pixels but stretched without cropping

C. The image will remain original size ignoring parameters

D. The URL will cause an error due to invalid parameters

Solution

1. Step 1: Analyze URL parameters

   The URL includes w=200 (width), h=100 (height), and fit=crop which crops the image to fit exactly the given dimensions.

2. Step 2: Understand transformation behavior

   Supabase will resize the image to 200 pixels wide and 100 pixels tall, cropping parts if needed to maintain aspect ratio.

3. Final Answer:

   The image will be resized to 200x100 pixels and cropped to fit exactly -> Option A

4. Quick Check:

   Resize + crop = exact fit size [OK]

Hint: fit=crop crops image to exact width and height [OK]

Common Mistakes:

• Assuming fit=crop stretches image without cropping
• Ignoring height parameter h
• Thinking parameters cause errors

4. You tried to resize an image using ?w=abc in the URL but it did not work. What is the likely problem?

medium

A. The parameter should be ?width=abc instead

B. The width parameter must be a number, not letters

C. Supabase does not support resizing images

D. You need to add &fit=stretch to resize properly

Solution

1. Step 1: Check parameter value type

   The width parameter w expects a numeric value representing pixels, not letters.

2. Step 2: Identify error cause

   Using abc as value is invalid and causes the resize to fail.

3. Final Answer:

   The width parameter must be a number, not letters -> Option B

4. Quick Check:

   Width value must be numeric [OK]

Hint: Width and height values must be numbers [OK]

Common Mistakes:

• Using text instead of numbers for size
• Changing parameter name incorrectly
• Assuming resizing needs extra fit parameter

5. You want to display a thumbnail of an image that is exactly 150x150 pixels, cropped to center, and with a grayscale effect. Which URL query parameters should you use?

hard

A. ?w=150&h=150&fit=crop&grayscale=true

B. ?width=150&height=150&crop=center&effect=grayscale

C. ?w=150&h=150&fit=crop&grayscale=1

D. ?w=150&h=150&fit=contain&grayscale=1

Solution

1. Step 1: Set size and cropping parameters

   Use w=150 and h=150 to set width and height, and fit=crop to crop the image to exact size centered.

2. Step 2: Apply grayscale effect correctly

   Supabase uses grayscale=1 to apply grayscale effect, not true.

3. Final Answer:

   ?w=150&h=150&fit=crop&grayscale=1 -> Option C

4. Quick Check:

   Crop + grayscale=1 for exact grayscale thumbnail [OK]

Hint: Use grayscale=1, not true, for grayscale effect [OK]

Common Mistakes:

• Using true instead of 1 for grayscale
• Using fit=contain instead of fit=crop
• Using wrong parameter names like width or effect