lsongdev / lsongdev/node-escpos

Current repo prints images with inverted colors

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Dominant language
TypeScript
Stars
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Forks
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Description

I managed to get the current repo running, everything works well except that images (including qrimage) white pixels are printed as black and black ones as white, I guess there's a issue with the function that converts pixels to black or white?
https://github.com/song940/node-escpos/blob/v3/packages/printer/src/image.ts#L26

this is the old code: https://github.com/song940/node-escpos/blob/ad1cade11f616f20bb112b3d5ecdfee85e77aff4/packages/printer/image.js#L30

I don't think there's an issue with my printer because the old version on npm prints images well

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Research direction

Start with packages/printer/src/image.ts at line 26 and compare its pixel conversion with the old packages/printer/image.js at line 30. Reproduce image printing with a QR image or another black-and-white image, then verify that white and black pixels produce the expected output on a printer.

Written by the indexing model from the issue text.

Assessment

Tech stack
nodejs, typescript
Domain
embedded-iot
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
45/100

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