Show HN: PlutoFilter- A single-header, zero-allocation image filter library in C

76 pointsposted 5 days ago
by sammycage

16 Comments

anitil

a day ago

I was wondering how it would do arbitrary-sized kernels without dynamic allocation (my guess was that it would use the input/output buffer as a temporary storage). The answer is that there's a _slight_ asterix to the 'zero-allocation' - the allocation is on the stack [0], but it's small-ish (2kb) and fixed size. So in an embedded context you'd just want to make sure you have headroom for this.

[0] https://github.com/sammycage/plutofilter/blob/main/plutofilt...

Neywiny

15 hours ago

It's interesting. On embedded, heap allocation is usually not done. If it is, it's permanent- free does nothing. Not always the case, you can enable a real alloc/free algorithm, but usually you don't need to free so it doesn't matter. The stack, though... If you take 2KB of stack and you haven't linked that much in, good luck trying to find that "bug" for why everything gets corrupted/crashes. My point here isn't that 2KB is big for embedded, it's actually that I'd prefer it just either statically allocates the memory or uses the heap so I can at least get an "out of memory" error

jlundberg

5 hours ago

Well done and great with all the examples. Kind of wish I had a use case for this already, but I probably have :)

mnaimd

19 hours ago

Wow

Really easy to add it into an existing project,

Written in C99...

Great job!

dxroshan

19 hours ago

Congratulation! Great work! I really like his PlutoVG, LunaSVG and PlutoSVG.

kookamamie

21 hours ago

Quite nice. Although, it seems to be making some pretty interesting assumptions. For example, most operations seem to assume ARGB inputs are premultiplied-alpha and will call PLUTOFILTER_UNPREMULTIPLY_PIXEL.

ephou7

a day ago

I'm not sure why single-header is an advantage over powerful libraries such as GEGL.

gregschlom

a day ago

The benefit of single-header, specifically, is that it's super easy to integrate with any project. You don't need to mess with your build system, or the library's build system, just include the file and you're good to go.

No allocation is useful for embedded / resource constrained targets.

im_down_w_otp

a day ago

Both the single header and the zero-allocation callouts can be desirable qualities for something used in an embedded (as in classical MCU-shaped) context.

edit: Seeing that it's also C99 makes me think that embedded applications might be what this was geared toward.

Calavar

a day ago

It fills the lightweight niche. You can build it on Windows without needing to drag in all of msys. I can see this as really useful for toy projects and demos.

vouaobrasil

21 hours ago

It's sort of like how a clean organized desk is an advantage to some but a hindrance to others....

malkia

a day ago

or ImageMagick, or plenty of others, with SIMD, GPU, etc. support.

mrheosuper

a day ago

easy to test and integrate to your project.

majorchord

a day ago

I'm not sure why walking is an advantage over a hot air balloon. /s

Try to understand that "advantage" can mean different things to different people. Your perspective and usecases might be totally opposite from someone else, and that doesn't mean either of you are wrong.

rossant

a day ago

Any SIMD/multicore capabilities?