Hybrid image aliasing #44803
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Hybrid image aliasing #44803
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This pull request was exported from Phabricator. Differential Revision: D58120352 |
Summary: This change introduces a new prop to the Android `Image` component: `resizeMultiplier`. This prop can be used when the `resizeMethod` is set to `resize`, and it directly modifies the resultant bitmap generated in memory from Fresco to be larger (or smaller) depending on the multiplier. A default of 1.0 means the bitmap size is designed to fit the destination dimensions. A multiplier greater than 1.0 will set the `ResizeOptions` provided to Fresco to be larger that the destination dimensions, and the resulting bitmap will be scaled from the hardware size. This new prop is most useful in cases where the destination dimensions are quite small and the source image is significantly larger. The `resize` resize method performs downsampling and significant image quality is lost between the source and destination image sizes, often resulting in a blurry image. By using a multiplier, the decoded image is slightly larger than the target size but smaller than the source image (if the source image is large enough). It's important to note that Fresco still chooses the closest power of 2 and will not scale the image larger than its source dimensions. If the multiplier yields `ResizeOptions` greater than the source dimensions, no downsampling occurs. Here's an example: If you have a source image with dimensions 200x200 and destination dimensions of 24x24, a `resizeMultiplier` of `2.0` will tell Fresco to downsample the image to 48x48. Fresco picks the closest power of 2 (so, 50x50) and decodes the image into a bitmap of that size. Without the multiplier, the closest power of 2 would be 25x25, which is half the quality. ## Changelog [Android][Added] - Adds a new `Image` prop `resizeMultiplier` to help increase quality of small images on low DPI devices Differential Revision: D58120352
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This pull request was exported from Phabricator. Differential Revision: D58120352 |
Base commit: a569c82 |
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This pull request has been merged in b6c3433. |
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This pull request was successfully merged by Peter Abbondanzo in b6c3433. When will my fix make it into a release? | How to file a pick request? |
This was referenced Jun 20, 2024
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Summary:
This change introduces a new prop to the Android
Imagecomponent:resizeMultiplier. This prop can be used when theresizeMethodis set toresize, and it directly modifies the resultant bitmap generated in memory from Fresco to be larger (or smaller) depending on the multiplier. A default of 1.0 means the bitmap size is designed to fit the destination dimensions. A multiplier greater than 1.0 will set theResizeOptionsprovided to Fresco to be larger that the destination dimensions, and the resulting bitmap will be scaled from the hardware size.This new prop is most useful in cases where the destination dimensions are quite small and the source image is significantly larger. The
resizeresize method performs downsampling and significant image quality is lost between the source and destination image sizes, often resulting in a blurry image. By using a multiplier, the decoded image is slightly larger than the target size but smaller than the source image (if the source image is large enough).It's important to note that Fresco still chooses the closest power of 2 and will not scale the image larger than its source dimensions. If the multiplier yields
ResizeOptionsgreater than the source dimensions, no downsampling occurs.Here's an example:
If you have a source image with dimensions 200x200 and destination dimensions of 24x24, a
resizeMultiplierof2.0will tell Fresco to downsample the image to 48x48. Fresco picks the closest power of 2 (so, 50x50) and decodes the image into a bitmap of that size. Without the multiplier, the closest power of 2 would be 25x25, which is half the quality.Changelog
[Android][Added] - Adds a new
ImagepropresizeMultiplierto help increase quality of small images on low DPI devicesDifferential Revision: D58120352