Benchmark results¶

Recorded 2026-09-21. Historical measurement. Not a measurement of the latest release. Run status: completed.

Which implementation takes less time? Compare every workload with libjpeg-turbo, the baseline. Lower time is better.

image-slash-star12 faster · 24 slowervs libjpeg-turbo · 0 equal · 4 not comparable

Observed median comparisons, not an overall score. Timing-only rows do not establish equal output; small differences may be noise.

Shorter bars = less time within a row. Click a column heading to sort. Scroll the table horizontally on small screens.

Baseline Median · vs baseline Lowest medianAmong comparable implementations

EncodeEncode JPEG8 × 8 · RGB · quality 85 · 4:2:0 5.96 µsBaselinelibjpeg-turbo. Output hash and size match. 2.96 µs2.01× fasterimage-slash-star. Output hash and size match. image-slash-starOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	2.96 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	5.96 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-8-q85-420

EncodeEncode JPEG32 × 32 · RGB · quality 85 · 4:2:0 9.17 µsBaselinelibjpeg-turbo. Output hash and size match. 5.62 µs1.63× fasterimage-slash-star. Output hash and size match. image-slash-starOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	5.62 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	9.17 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-32-q85-420

EncodeEncode JPEG63 × 65 · RGB · quality 85 · 4:2:0 21.8 µsBaselinelibjpeg-turbo. Output hash and size match. 23 µs1.06× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	23 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	21.8 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-63x65-q85-420

EncodeEncode JPEG128 × 128 · RGB · quality 10 · 4:2:0 35.2 µsBaselinelibjpeg-turbo. Output hash and size match. 50.2 µs1.43× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	50.2 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	35.2 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q10-420

EncodeEncode JPEG128 × 128 · RGB · quality 50 · 4:2:0 50.3 µsBaselinelibjpeg-turbo. Output hash and size match. 77.7 µs1.55× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	77.7 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	50.3 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q50-420

EncodeEncode JPEG128 × 128 · RGB · quality 85 · 4:2:0 65.9 µsBaselinelibjpeg-turbo. Output hash and size match. 99.8 µs1.51× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	99.8 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	65.9 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q85-420

EncodeEncode JPEG128 × 128 · RGB · quality 100 · 4:2:0 85.2 µsBaselinelibjpeg-turbo. Output hash and size match. 116 µs1.36× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	116 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	85.2 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q100-420

EncodeEncode JPEG512 × 512 · RGB · quality 10 · 4:2:0 585 µsBaselinelibjpeg-turbo. Output hash and size match. 1.15 ms1.96× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	1.15 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	585 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-512-q10-420

EncodeEncode JPEG512 × 512 · RGB · quality 85 · 4:2:0 1.25 msBaselinelibjpeg-turbo. Output hash and size match. 2.35 ms1.88× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	2.35 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	1.25 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-512-q85-420

EncodeEncode JPEG1024 × 1024 · RGB · quality 85 · 4:2:0 5.54 msBaselinelibjpeg-turbo. Output hash and size match. 9.4 ms1.7× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	9.4 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	5.54 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-1024-q85-420

EncodeEncode JPEG128 × 128 · RGB · quality 85 · 4:2:2 95 µsBaselinelibjpeg-turbo. Output hash and size match. 159 µs1.67× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	159 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	95 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q85-422

EncodeEncode JPEG128 × 128 · RGB · quality 85 · 4:4:4 146 µsBaselinelibjpeg-turbo. Output hash and size match. 240 µs1.65× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	240 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	146 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q85-444

EncodeEncode JPEG128 × 128 · RGB · quality 85 · 4:2:0 · optimized 243 µsBaselinelibjpeg-turbo. Output hash and size match. 242 µs1.01× fasterimage-slash-star. Output hash and size match. image-slash-starOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	242 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	243 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q85-optimized

EncodeEncode JPEG128 × 128 · RGB · quality 85 · 4:2:0 · progressive 750 µsBaselinelibjpeg-turbo. Output hash and size match. 816 µs1.09× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	816 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	750 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q85-progressive

EncodeEncode JPEG128 × 128 · RGB · quality 85 · 4:2:0 · restart every 4 rows 72.9 µsBaselinelibjpeg-turbo. Output hash and size match. 109 µs1.5× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	109 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	72.9 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-128-q85-restart4

EncodeEncode JPEG128 × 128 · GRAY · quality 85 61 µsBaselinelibjpeg-turbo. Output hash and size match. 55.8 µs1.09× fasterimage-slash-star. Output hash and size match. image-slash-starOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	55.8 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	61 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.gray-128-q85

EncodeEncode JPEG512 × 512 · GRAY · quality 85 1.05 msBaselinelibjpeg-turbo. Output hash and size match. 1.18 ms1.13× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	1.18 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	1.05 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.gray-512-q85

EncodeEncode JPEG128 × 128 · CMYK · quality 85 212 µsBaselinelibjpeg-turbo. Output differs · speed comparison withheld. 312 µsNot comparableimage-slash-star. Output differs · speed comparison withheld. Not comparableOutput differs · speed comparison withheld

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	312 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: False
libjpeg-turbo	212 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: False

Workload ID: encode.cmyk-128-q85

EncodeEncode JPEG512 × 512 · CMYK · quality 85 3.87 msBaselinelibjpeg-turbo. Output differs · speed comparison withheld. 6.8 msNot comparableimage-slash-star. Output differs · speed comparison withheld. Not comparableOutput differs · speed comparison withheld

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	6.8 ms	Not measured	Not measured	5	completed; output hash match: False; byte length match: False
libjpeg-turbo	3.87 ms	Not measured	Not measured	5	completed; output hash match: False; byte length match: False

Workload ID: encode.cmyk-512-q85

EncodeEncode JPEG127 × 129 · RGB · quality 85 · 4:2:0 72.9 µsBaselinelibjpeg-turbo. Output hash and size match. 115 µs1.58× slowerimage-slash-star. Output hash and size match. libjpeg-turboOutput hash and size match

Encode JPEG · Timing boundary: public codec operation including context/output lifetime. Sample unit: round median. Percentiles show spread, not confidence intervals.

Implementation	Median	P90	P95	Samples	Recorded result
image-slash-star	115 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	72.9 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True

Workload ID: encode.rgb-127x129-q85-420

DecodeDecode JPEG8 × 8 · RGB · quality 85 · 4:2:0 5.17 µsBaselinelibjpeg-turbo. Output hash and size match. 1.96 µs2.64× fasterimage-slash-star. Output hash and size match. image-slash-starOutput hash and size match