[Bug report] Inconsistent resizing behavior between iOS and Android in thumbnailDataWithSize

[choi88andys]

Version

3.6.4

Platforms

iOS, Android

Device Model

iPhone 13(iOS 18.0), Android emulator API 30

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• No issues found!

How to reproduce?

Steps to reproduce

• Load an image with dimensions 1000x2000.
• Call thumbnailDataWithSize(200) to resize the image.
• Compare the result on iOS and Android.

Description

I've encountered an issue where resizing images using the thumbnailDataWithSize method produces inconsistent results on iOS and Android.
The image should be resized proportionally, maintaining the same aspect ratio across both platforms.

For example, resizing an image of size 1000x2000 with a target size of 200 should result in 200x400.
On Android, the image is correctly resized to 200x400, which is the expected result. However, on iOS, the image is resized to 100x200.

This suggests that Android scales the smaller dimension to 200, whereas iOS scales the larger dimension to 200.

Could you clarify if this behavior is intentional or if it's a bug?

Logs

Example code (optional)

// I tested using package image
import 'package:image/image.dart' as img;

final thumbnail = await asset.thumbnailDataWithSize(
  const ThumbnailSize(200, 200),
);

final image = img.decodeImage(thumbnail!)!;
print('image.width: ${image.width}');
print('image.width: ${image.height}');

Contact

No response

[fluttercandies-dev]

AI Summary: The thumbnailDataWithSize method returns inconsistent image dimensions on iOS and Android. On iOS, the larger dimension is scaled to the target size, while Android scales the smaller dimension.