50 lines
1.5 KiB
Markdown
50 lines
1.5 KiB
Markdown
title: process_image
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---
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module: lektor.imagetools
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---
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signature: ctx, source_image, dst_filename, width=None, height=None, mode=ThumbnailMode.DEFAULT
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---
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summary: Build an image from a source image, optionally compressing and resizing.
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---
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type: function
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---
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version_added: 2.0
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---
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body:
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This function takes a [Context :ref](../../build/context/) object, the
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absolute paths to the image's source and target files, the target image's
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width and/or height, and the operation mode.
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In the default mode, if width or height are `None`, they are calculated
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from the source image's dimensions so that the image is scaled proportionally.
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Used internally for the implementation of [thumbnail :ref](../../db/record/thumbnail), and exposed as an API for image-processing plugins.
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## Example
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```python
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from lektor.build_programs import AttachmentBuildProgram
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from lektor.context import get_ctx
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from lektor.db import Image
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from lektor.imagetools import process_image, ThumbnailMode
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from lektor.pluginsystem import Plugin
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class ImageCropBuildProgram(AttachmentBuildProgram):
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def build_artifact(self, artifact):
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ctx = get_ctx()
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width, height = 600, 400
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source_img = artifact.source_obj.attachment_filename
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artifact.ensure_dir()
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process_image(ctx,
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source_img,
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artifact.dst_filename,
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width, height, mode=ThumbnailMode.CROP)
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class ImageCropPlugin(Plugin):
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def on_setup_env(self, **extra):
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self.env.add_build_program(Image, ImageCropBuildProgram)
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```
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