jcupitt

We just banned gen-AI PRs, it seems to be working so far.

Commercial dev is about results and money, and that makes AI almost impossible to resist.

OSS has always been about process. The pleasure is in tinkering with code, collaborating with friends on a fun new idea, and helping people. I don't care about speed.

libvips shouldn't be calling imagemagick for heif decode, it has a nice one built in. Unless you were using a very old libvips!

I've found jemalloc works best for long running libvips processes, fwiw.

Hello, looks nice! I had a few thoughts:

- I'd consider adding support for libvips smartcrop, ICC colour management, HDR, image alpha

- can you join pipelines? you could have one making a background, one making a foreground, then composite them, for example

- your benchmarks don't measure peak memory use, it can be a useful thing to test, especially if people are processing large images (eg. the output of every modern smartphone sigh)

- have you benchmarked against nip4, the official libvips GUI? it has a CLI mode you can run with GNU parallel

- I agree, a CLI mode for your tool sounds useful

Some packages with native code components (like sharp) will use these hooks to download the correct precompiled native binary for you.

sharp downloads over https and checks the sha256 (I think?) of the archive.

Hello, libvips author here, you can get it to do the OKLab averaging for you. For example, using pyvips (ahem, untested):

image = pyvips.Image.new_from_file(filename, access="sequential")

scale = min(200 / image.width, 200 / image.height)

thumbnail = image.colourspace("oklab").resize(scale).extract_bands(0, n=3)

rgbf = thumbnail.write_to_memory()

That'll stream the source image and make a RGBRGBRGB memory buffer of single precision floats. You could perhaps use kernel="linear" and avoid any ringing from lanczos3.

I think I would downsample in a linear light space, like scRGB. Averaging there means averaging photons, which will surely be better than OKLab. Maybe switch to OKLab for clustering. Though of course I've not tested it.

libvips uses imagemagick (via libMagick) for BMP load and save, fwiw

It's just `vips copy src.heic dst.jpg`.

Cleanup can be very useful if you depend on a library that does not support arenas.

`free(NULL);` will crash on some platforms that gcc supports, I believe.

I'm the libvips author, I should have said, so I'm not very neutral. But at least on that test it's usefully quicker and less memory hungry.