Compress Simplified Chinese slow

[DadddyWang]

Hello. I want to know that the compression speed of subset compression in Simplified Chinese is very slow. Is there any good optimization scheme or has anyone solved this problem in the past?

[DadddyWang]

I wrote an api interface to call this service, but more than 60s will exceed the timeout time of nginx

[justvanrossum]

If it's about subsetting, you should look into the HarfBuzz subsetter, which is much faster:

• https://docs.google.com/presentation/d/1RMkpikAUmdIXaz3eEDYFETWfAwnT0Vw8_oC8Ait5xqs/edit#slide=id.g41919619d9_0_65
  (But I can't find a link for how to install and how to operate :( )

If it's about woff2-compressing an already subsetted font: woff2 compression can be quite slow for big fonts, but you could try this tool instead: https://github.com/google/woff2

[DadddyWang]

import os, uuid
from pathlib import Path
from fontTools.subset import main as subsetFunc

def compressFont(
    fontLocalPath: str,
    fontType: str,
    unicodes: str,
    subset: str
):
    outputFileName = str(uuid.uuid4()) + '.' + fontType
    outputFilePath = '/tmp/font_output/' + outputFileName

    parameter = [
        fontLocalPath,
        "--unicodes=%s" % unicodes,
        "--layout-features=*",
        "--name-IDs=*",
        "--name-languages=*",
        "--flavor=%s" % fontType,
        "--output-file=%s" % outputFilePath,
    ]
    if subset:
        for pm in subset:
            parameter.append(pm)
    
    subsetFunc(parameter)

    return outputFilePath

__all__ = [
    'compressFont',
    'outputFileDir',
]

[justvanrossum]

With what kind of inputs do you call that function? What inputs do you give to get the 80 seconds timing vs. 1-2 seconds? Are inputs OTF or TTF, is output woff2? How big are the input files? How many characters does the subset contain? Etc.

Btw. my original comment still holds: if you need this to be faster, you are very likely to get better results using the HarfBuzz subsetter.

[DadddyWang]

input ttf output woff The file size in 80 seconds is 36mb and have It's about 65535 characters, and the file size in 2 seconds is 13mb,parameters are the same.
I will try HarfBuzz subsetter.THX

[justvanrossum]

What are the sizes of the resulting files?

[DadddyWang]

13.1mb

What are the sizes of the resulting files?