python-pillow / python-pillow/Pillow

Support scan script selection for `progressive` argument

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Enhancement JPEG
Dominant language
Python
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Avg merge
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Merged PRs (30d)
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Description

This is a feature request. Apologies if it already exists and please direct me to the right option.

For the JPEG progressive option, the current code calls jpeg_simple_progression at https://github.com/python-pillow/Pillow/blob/fdbd719da4c77c7e23e2e9e9b71d0d177f2d3369/src/libImaging/JpegEncode.c#L218

Would it be possible to support an argument to specify the scan script to use?

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First steps

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  3. Fork the repository and make your change on a branch.
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Research direction

Start in src/libImaging/JpegEncode.c at the jpeg_simple_progression call, then trace how the JPEG progressive option reaches that encoder. Determine how a caller could select a scan script and identify the relevant tests or test entry points before changing the API. Done means the progressive option accepts a scan-script selection and uses it when encoding JPEGs.

Written by the indexing model from the issue text.

Assessment

Tech stack
c, python
Domain
computer-vision
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
30/100

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