Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

[Bug] Weird BMP load bug

See original GitHub issue

Expected Behavior

The copied bmp file should be exactly the same as the original one.

Current Behavior

For some reason for this bmp file content gets moved/shifted. It does not happen for all the bmp files.

Failure Information (for bugs)

Steps to Reproduce

I’ve created minial reproducible repo:

git git@github.com:elderapo/jimp-bmp-bug.git
cd ./jimp-bmp-bug
yarn
yarn start

Screenshots

Context

Jimp Version: ^0.8.4
Operating System: Ubuntu 14.04
Node version: v11.10.0, v12.10.0

Failure Logs

The loading system for bmp files seems to be broken. Exact same thing happens when reading bmp file from disk, buffer. Even when file is saved to a different format it still gets shifted.

Issue Analytics

State:
Created 4 years ago
Reactions:2
Comments:6

Top GitHub Comments

1reaction

hipstersmoothiecommented, Oct 15, 2019

I have a fork of bmp-ts I plan to integrate at some point. If you can find and fix the bug there I’ll merge the changes into jimp

https://github.com/hipstersmoothie/bmp-ts

1reaction

cymplecycommented, Oct 15, 2019

I’ve been trying to run down an issue with bmp-js (which I believe jimp uses to read bmp files). AFAICT bmp-js does not use the offset value to the actual bitmap data contained in the header info of a bmp file. It just assumes that the bitmap follows on from the header.

I discovered this as I found that bmp files saved from GIMP have extra information in them that bmp files saved from both MSPaint and paint.net don’t put in (see https://stackoverflow.com/questions/30505928/gimp-how-to-export-an-image-to-bmp-without-the-color-space-information-using-a for some information on this extra information )

Anyway - I ended up here and tried your from.bmp file out - and it has extra bytes between the header and the actual bitmap as well and I can replicate your fault in my code.

If I open from.bmp in Win MSPaint.exe and resave it as frompaint.bmp - the extra data is removed and reading the file works perfectly in jimp

I don’t know how to resolve the issue since bmp-js doesn’t seem to be maintained anymore