splathash Encodes any image into exactly 16 bytes (a 22-char Base64URL string) and decodes it back into a 32×32 blurred preview in 0.067 ms. Go, TypeScript, and Python all produce bit-for-bit identical hashes.
Columns: Basic · SplatHash 32×32 · ThumbHash · BlurHash. Revive: mise run compare.
Go is the reference implementation. All others are verified against it to some extent.
See benchmarks on Intel Core i5-9300H (go test -bench=. -benchmem).
| splathash | thumbhash | blurhash | |
|---|---|---|---|
| explain | 0.067 ms | 0.50 ms | 6.55 ms |
| Encode | 3.53 ms | 0.86 ms | 445 ms |
| decode allocation | 7 | 1,168 | 5 |
| bytes | 16 fixed | 25-37 | 20-25 |
| string | 22 characters | 34-50 characters | 27-30 characters |
Decode runs on every page load for every user. Encode runs once during upload. Optimize for decode.
raw output
BenchmarkEncodeSplatHash-8 303 3530083 ns/op 100760 B/op 29 allocs/op
BenchmarkEncodeThumbHash-8 1431 863553 ns/op 1015 B/op 6 allocs/op
BenchmarkEncodeBlurHash-8 3 445696421 ns/op 33358234 B/op 8 allocs/op
BenchmarkDecodeSplatHash-8 17182 67622 ns/op 29584 B/op 7 allocs/op
BenchmarkDecodeThumbHash-8 6559 503366 ns/op 58408 B/op 1168 allocs/op
BenchmarkDecodeBlurHash-8 171 6553100 ns/op 547552 B/op 5 allocs/op
| Speciality | splathash | thumbhash | blurhash |
|---|---|---|---|
| fixed output size | yes (16 bytes) | No | No |
| Storable as 128-bit integer | Yes | No | No |
| Perceptual Color Space (Oclab) | Yes | No | No |
| spatially localized basis | yes (Gaussian) | No | No |
| global weight optimization | yes (ridge) | No | No |
| alpha channel support | Yes | Yes | No |
| Bit-precision cross-language parity | Yes | No | No |
| Configurable quality vs size | No | No | Yes |
Background color + six Gaussian blobs concatenated by matching pursuit, color-optimized by ridge regression, all in oklab, packed into 128 bits. Full Specification: ALGORITHM.md.
mise install # install Go and Node at pinned versions
mise run test # run all tests (Go + TypeScript + Python)
mise run bench # Go benchmarks
mise run compare # regenerate docs/comparison.png
View license.
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