d6caa9dc0b
This tool uses existing libraries: image, imageio, imageio-lite, imagediff to perform difference comparison for on-disk images. We refactor renderdiff to use this tool instead of using python dependencies. Co-authored-by: Ben Doherty <bendoherty@google.com>
55 lines
1.5 KiB
Markdown
55 lines
1.5 KiB
Markdown
# diffimg
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`diffimg` is a command-line tool for comparing two images using the `imagediff` library's tolerance logic. It supports various image formats and allows for fine-grained control over comparison thresholds via JSON configuration and optional masking.
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## Usage
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```bash
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diffimg [options] <reference> <candidate>
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```
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### Arguments
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- `<reference>`: Path to the golden/expected image.
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- `<candidate>`: Path to the test/actual image.
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### Options
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- `--config <path>`: Path to a JSON configuration file defining comparison thresholds.
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- `--mask <path>`: Path to a grayscale mask image (0 = ignore, >0 = compare).
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- `--diff <path>`: Path to output a visual difference image (unmasked absolute difference).
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- `--help, -h`: Print help message.
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## Output
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The tool outputs a JSON object to `stdout` containing the comparison results:
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```json
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{
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"status": 0,
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"passed": true,
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"failingPixelCount": 0,
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"maxDiffFound": [0.0, 0.0, 0.0, 0.0]
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}
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```
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### Status Codes
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- `0`: PASSED (Images are considered the same within tolerance)
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- `1`: SIZE_MISMATCH (Images have different dimensions)
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- `2`: PIXEL_DIFFERENCE (Images differ beyond the allowed tolerance)
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## Configuration Format
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The optional JSON configuration follows the `imagediff` schema:
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```json
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{
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"mode": "LEAF",
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"maxAbsDiff": 0.01,
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"maxFailingPixelsFraction": 0.05
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}
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```
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## Dependencies
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- `libs/imagediff`: Comparison logic.
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- `libs/imageio`: Primary image decoding (PNG, HDR, EXR).
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- `libs/imageio-lite`: Fallback decoding (TIFF).
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