4 ms·

> compressing them as much as I could I noticed this takes hours with ect. pngout ranks in second place with respectable results, but is fifty to hundred times

• bscphil 5y ago
  What command are you using? I find `ect --strict -9` to be extremely fast, much better than oxipng or zopfli. `-9` provides the maximum compression level built in to the program; you could use the advanced options like `--allfilters-b` but I've found that this produces negligible additional compression (similar to zopfli's advanced modes) and mostly just go with `-9`. As I said in the OP, optimizing the seven test images provided by the QOI webpage took only a few seconds.
  • bmn__ 5y ago
    You're contradicting yourself. Either you have used `--allfilters-b --pal_sort=120 --mt-deflate=$(nproc)` and the quoted text in my previous post is true, or you haven't, and then the quote is false.
    • bscphil 5y ago
      > compressing them as much as I could Yes, this is technically not 100% true, it's just 99.9% true. Previous tests have found those additional options to provide negligible improvement in compression. Very rarely do I get even 1% more compression out of enabling all of them compared to ect's highest built-in compression level (`-9`). Basically what I'm getting at is that ect seems to hit the point of diminishing returns much quicker than anything I've personally tested. I'm curious if you have found a tool that achieves the same or better compression more quickly, that's why I asked.