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gianni-rosato
fssimu2
Zig2025–2025
gianni-rosato / fssimu2

fssimu2

Fast SSIMULACRA2 derivative implementation in Zig.

Explore on GitHubRead Hacker News discussions
2Distinct people
3Mentions
0Explicit recommenders
50GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Fast SSIMULACRA2 derivative implementation in Zig.

GitHub

Where it is used

No documented product use has been verified yet.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 5:04:57 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by hour3 dated mentions

Observed mentions: 2025-10-03 20:36:44 UTC to 2025-10-04 20:51:33 UTC.

012025-10-03 20:00:00 UTC to 2025-10-03 21:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 commentsOct 3, 20:002025-10-03 21:00:00 UTC to 2025-10-03 22:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-03 22:00:00 UTC to 2025-10-03 23:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-03 23:00:00 UTC to 2025-10-04 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 00:00:00 UTC to 2025-10-04 01:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 01:00:00 UTC to 2025-10-04 02:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 02:00:00 UTC to 2025-10-04 03:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 03:00:00 UTC to 2025-10-04 04:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 04:00:00 UTC to 2025-10-04 05:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 05:00:00 UTC to 2025-10-04 06:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 06:00:00 UTC to 2025-10-04 07:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 07:00:00 UTC to 2025-10-04 08:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 08:00:00 UTC to 2025-10-04 09:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsOct 4, 08:002025-10-04 09:00:00 UTC to 2025-10-04 10:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2025-10-04 10:00:00 UTC to 2025-10-04 11:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 11:00:00 UTC to 2025-10-04 12:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 12:00:00 UTC to 2025-10-04 13:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 13:00:00 UTC to 2025-10-04 14:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 14:00:00 UTC to 2025-10-04 15:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 15:00:00 UTC to 2025-10-04 16:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 16:00:00 UTC to 2025-10-04 17:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 17:00:00 UTC to 2025-10-04 18:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 18:00:00 UTC to 2025-10-04 19:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 19:00:00 UTC to 2025-10-04 20:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-04 20:00:00 UTC to 2025-10-04 21:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsOct 4, 20:00

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
Oct 3, 20:002025-10-03 20:00:00 UTC2025-10-03 21:00:00 UTC110
Oct 3, 21:002025-10-03 21:00:00 UTC2025-10-03 22:00:00 UTC000
Oct 3, 22:002025-10-03 22:00:00 UTC2025-10-03 23:00:00 UTC000
Oct 3, 23:002025-10-03 23:00:00 UTC2025-10-04 00:00:00 UTC000
Oct 4, 00:002025-10-04 00:00:00 UTC2025-10-04 01:00:00 UTC000
Oct 4, 01:002025-10-04 01:00:00 UTC2025-10-04 02:00:00 UTC000
Oct 4, 02:002025-10-04 02:00:00 UTC2025-10-04 03:00:00 UTC000
Oct 4, 03:002025-10-04 03:00:00 UTC2025-10-04 04:00:00 UTC000
Oct 4, 04:002025-10-04 04:00:00 UTC2025-10-04 05:00:00 UTC000
Oct 4, 05:002025-10-04 05:00:00 UTC2025-10-04 06:00:00 UTC000
Oct 4, 06:002025-10-04 06:00:00 UTC2025-10-04 07:00:00 UTC000
Oct 4, 07:002025-10-04 07:00:00 UTC2025-10-04 08:00:00 UTC000
Oct 4, 08:002025-10-04 08:00:00 UTC2025-10-04 09:00:00 UTC000
Oct 4, 09:002025-10-04 09:00:00 UTC2025-10-04 10:00:00 UTC101
Oct 4, 10:002025-10-04 10:00:00 UTC2025-10-04 11:00:00 UTC000
Oct 4, 11:002025-10-04 11:00:00 UTC2025-10-04 12:00:00 UTC000
Oct 4, 12:002025-10-04 12:00:00 UTC2025-10-04 13:00:00 UTC000
Oct 4, 13:002025-10-04 13:00:00 UTC2025-10-04 14:00:00 UTC000
Oct 4, 14:002025-10-04 14:00:00 UTC2025-10-04 15:00:00 UTC000
Oct 4, 15:002025-10-04 15:00:00 UTC2025-10-04 16:00:00 UTC000
Oct 4, 16:002025-10-04 16:00:00 UTC2025-10-04 17:00:00 UTC000
Oct 4, 17:002025-10-04 17:00:00 UTC2025-10-04 18:00:00 UTC000
Oct 4, 18:002025-10-04 18:00:00 UTC2025-10-04 19:00:00 UTC000
Oct 4, 19:002025-10-04 19:00:00 UTC2025-10-04 20:00:00 UTC000
Oct 4, 20:002025-10-04 20:00:00 UTC2025-10-04 21:00:00 UTC101

What Hacker News says

3 sources
computerbuster·Oct 4, 2025
Hi, author here – the README covers this in the Performance section: https://github.com/gianni-rosato/fssimu2?tab=readme-ov-file#... If you run the `validate.py` script available in the repo, you should see correlation numbers similar to what I've pre-tested & made available in the README: fssimu2 achieves 99.97% linear correlation with the reference implementation's scores. fssimu2 is still missing some functionality (like ICC profile reading) but the goal was to produce a production-oriented implementation that is just as useful while being much faster (example: lower memory footprint and speed improvements make fssimu2 a lot more useful in a target quality loop). For research-oriented use cases where the exact SSIMULACRA2 score is desirable, the reference implementation is a better choice. It is worth evaluating whether or not this is
Read the rest
your use case; an implementation that is 99.97% accurate is likely just as useful to you if you are doing quality benchmarks, target quality, or something else where SSIMULACRA2's correlation to subjective human ratings is more important than the exactness of the implementation to the reference.
In Fast SSIMULACRA2 Implementation in Zig
gforce_de·Oct 4, 2025
It does not match with the reference implementation in my side: #!/bin/sh # originally from https://jpegxl.info/images/precision-machinery-shapes-golden-substance-with-roboti… # URL1="http://intercity-vpn.de/files/2025-10-04/upload/precision-machinery-shapes-golden-…" # URL2="http://intercity-vpn.de/files/2025-10-04/upload/image-png-all-pngquant-q13.png" curl "$URL1" -so test.png curl "$URL2" -so distorted.png # https://github.com/cloudinary/ssimulacra2/tree/main ssimulacra2 test.png distorted.png 5.90462597 # https://github.com/gianni-rosato/fssimu2 fssimu2 test.png distorted.png 2.17616860
In Fast SSIMULACRA2 Implementation in Zig

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