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Frommi / miniz_oxide

Rust replacement for miniz
MIT License
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inflate::core::init_tree() is slow #82

Closed Shnatsel closed 1 year ago

Shnatsel commented 4 years ago

When opening small-ish images with png crate more than 50% of time is spent in inflate::core::init_tree function. This makes png crate 3x slower than spng according to spng crate benchmarks. Using larger images closes the gap.

Sample image demonstrating the issue (25Kb): https://github.com/aloucks/spng-rs/blob/master/spng/tests/test-002.png

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Shnatsel commented 4 years ago

The difference is not large in absolute terms - it's 3ms with png vs 1ms with spng. But that could still be noticeable in a networked setting (2 more ms to establish a connection) or when processing a lot of small images e.g. in machine learning workloads.