Benchmark results¶

Recorded 2026-11-11. 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 · 22 slowervs libjpeg-turbo · 0 equal · 6 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. 2.88 µs2.07× 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	2.88 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 8.58 µsBaselinelibjpeg-turbo. Output hash and size match. 5.25 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	5.25 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	8.58 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 21.9 µsBaselinelibjpeg-turbo. Output hash and size match. 19.9 µs1.1× 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	19.9 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	21.9 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 µsBaselinelibjpeg-turbo. Output hash and size match. 47.7 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	47.7 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	35 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 48.4 µsBaselinelibjpeg-turbo. Output hash and size match. 63 µs1.3× 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	63 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	48.4 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 68.3 µsBaselinelibjpeg-turbo. Output hash and size match. 81.8 µs1.2× 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	81.8 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	68.3 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 82.7 µsBaselinelibjpeg-turbo. Output hash and size match. 101 µs1.22× 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	101 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	82.7 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 · 4:2:0 554 µsBaselinelibjpeg-turbo. Output hash and size match. 1.03 ms1.85× 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	1.03 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	554 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 1.1 msBaselinelibjpeg-turbo. Output hash and size match. 1.92 ms1.74× 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	1.92 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	1.1 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 4.52 msBaselinelibjpeg-turbo. Output hash and size match. 7.38 ms1.63× 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	7.38 ms	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	4.52 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 95.2 µsBaselinelibjpeg-turbo. Output hash and size match. 137 µs1.44× 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	137 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	95.2 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 · 4:4:4 143 µsBaselinelibjpeg-turbo. Output hash and size match. 213 µs1.49× 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	213 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	143 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 220 µsBaselinelibjpeg-turbo. Output hash and size match. 212 µs1.04× 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	212 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	220 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 691 µsBaselinelibjpeg-turbo. Output hash and size match. 684 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	684 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	691 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 67.7 µsBaselinelibjpeg-turbo. Output hash and size match. 80.2 µs1.19× 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	80.2 µs	Not measured	Not measured	5	completed; output hash match: True; byte length match: True
libjpeg-turbo	67.7 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 54.2 µsBaselinelibjpeg-turbo. Output differs · speed comparison withheld. 43.5 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	43.5 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: True
libjpeg-turbo	54.2 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: True

Workload ID: encode.gray-128-q85

EncodeEncode JPEG512 × 512 · GRAY · quality 85 861 µsBaselinelibjpeg-turbo. Output differs · speed comparison withheld. 998 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	998 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: True
libjpeg-turbo	861 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: True

Workload ID: encode.gray-512-q85

EncodeEncode JPEG128 × 128 · CMYK · quality 85 185 µsBaselinelibjpeg-turbo. Output differs · speed comparison withheld. 296 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	296 µs	Not measured	Not measured	5	completed; output hash match: False; byte length match: False
libjpeg-turbo	185 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 3.08 msBaselinelibjpeg-turbo. Output differs · speed comparison withheld. 4.97 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	4.97 ms	Not measured	Not measured	5	completed; output hash match: False; byte length match: False
libjpeg-turbo	3.08 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. 92.4 µs1.27× 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	92.4 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 4.83 µsBaselinelibjpeg-turbo. Output hash and size match. 1.83 µs2.64× fasterimage-slash-star. Output hash and size match. image-slash-starOutput hash and size match