Benchmarks

The numbers below are generated from bench/results/*.json by pnpm bench:report; nothing is estimated. Corpus: 24 images (bench/corpus/manifest.json lists sources, sizes and SHA-256). Hardware: Apple M4 Pro (14 cores, 24 GB), macOS arm64, Node 24.15, headless Chromium 156.

Reproduce:

pnpm bench:corpus    # download/render the corpus
pnpm bench:node      # Optiq vs libvips (sharp); peak RSS per run in a fresh process
pnpm bench:browser   # Optiq vs browser-image-compression and canvas, in Chromium
pnpm bench:report    # regenerate bench/results/RESULTS.md

How to read it: fixed-quality baselines do not target a quality, so compare size and SSIM together. The head-to-head tables count, per image, which tool is smaller and at least as good.

Node.js: Optiq engine vs libvips (sharp)

Environment: {"runtime":"node v24.15.0","platform":"darwin-arm64","cpu":"Apple M4 Pro","cores":14,"memGB":24,"sharp":"0.35.5","date":"2026-10-28T05:27:34.642Z","merged":["2026-10-27T12:09:36.746Z: sc-balanced,sc-balanced-nometa","2026-10-27T13:05:48.482Z: sc-balanced,sc-balanced-nometa,sc-visually-lossless,sc-lossless","2026-10-27T14:22:30.306Z: sc-fast","2026-10-28T05:27:34.642Z: sc-fast"]}

Perceptual (lossy) results by category

SSIM is Optiq's metric (8x8 windows, Y/Cb/Cr 6:1:1, active-window pooling), computed identically for every tool against the decoded input. Fixed-quality baselines do not target a quality, so compare size and SSIM.

photo (10 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	10	2.80 MB → 0.61 MB	78.3%	65.2%	0.9767	0.9753	10/10	0/10	1.0 s	218 MB
sc-balanced-nometa	10	2.80 MB → 0.61 MB	78.3%	65.2%	0.9767	0.9753	10/10	0/10	1.0 s	217 MB
sc-visually-lossless	10	2.80 MB → 0.98 MB	65.1%	36.4%	0.9909	0.9904	10/10	10/10	1.7 s	226 MB
sharp-mozjpeg-q80	10	2.80 MB → 0.66 MB	76.2%	51.7%	0.9649	0.9487	2/10	0/10	34 ms	102 MB
sharp-webp-q80	10	2.80 MB → 0.66 MB	76.5%	59.0%	0.9739	0.9613	4/10	0/10	35 ms	102 MB
sharp-avif-q50	10	2.80 MB → 0.32 MB	88.7%	77.8%	0.9510	0.9279	0/10	0/10	496 ms	123 MB
sc-fast	10	2.80 MB → 0.77 MB	72.5%	49.8%	0.9789	0.9762	10/10	0/10	298 ms	148 MB

photo-large (3 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	3	7.58 MB → 4.43 MB	41.5%	40.0%	0.9794	0.9752	3/3	0/3	4.0 s	584 MB
sc-balanced-nometa	3	7.58 MB → 3.73 MB	50.8%	51.6%	0.9791	0.9753	3/3	0/3	10.3 s	936 MB
sc-visually-lossless	3	7.58 MB → 5.30 MB	30.1%	29.9%	0.9933	0.9917	3/3	3/3	3.8 s	594 MB
sharp-mozjpeg-q80	3	7.58 MB → 5.68 MB	25.0%	24.8%	0.9958	0.9957	3/3	3/3	790 ms	194 MB
sharp-webp-q80	3	7.58 MB → 5.25 MB	30.7%	34.7%	0.9800	0.9793	3/3	0/3	836 ms	187 MB
sharp-avif-q50	3	7.58 MB → 2.82 MB	62.8%	63.3%	0.9732	0.9632	0/3	0/3	9.5 s	540 MB
sc-fast	3	7.58 MB → 4.40 MB	42.0%	45.4%	0.9779	0.9752	3/3	0/3	2.6 s	551 MB

screenshot (2 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	2	0.44 MB → 0.04 MB	90.6%	90.2%	0.9910	0.9819	2/2	1/2	9.2 s	694 MB
sc-balanced-nometa	2	0.44 MB → 0.04 MB	90.6%	90.2%	0.9910	0.9819	2/2	1/2	9.2 s	585 MB
sc-visually-lossless	2	0.44 MB → 0.04 MB	90.5%	90.1%	0.9951	0.9902	2/2	2/2	20.2 s	665 MB
sharp-mozjpeg-q80	2	0.44 MB → 0.24 MB	45.7%	46.7%	0.9619	0.9304	1/2	1/2	132 ms	123 MB
sharp-webp-q80	2	0.44 MB → 0.16 MB	62.8%	62.6%	0.9853	0.9724	1/2	1/2	134 ms	115 MB
sharp-avif-q50	2	0.44 MB → 0.08 MB	81.1%	81.0%	0.9951	0.9915	2/2	2/2	1.4 s	224 MB
sc-fast	2	0.44 MB → 0.10 MB	76.9%	78.1%	1.0000	1.0000	2/2	2/2	883 ms	352 MB

text-graphic (2 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	2	0.40 MB → 0.03 MB	91.8%	87.5%	0.9988	0.9977	2/2	2/2	2.2 s	407 MB
sc-balanced-nometa	2	0.40 MB → 0.03 MB	91.8%	87.5%	0.9988	0.9977	2/2	2/2	2.2 s	403 MB
sc-visually-lossless	2	0.40 MB → 0.03 MB	92.0%	88.2%	0.9990	0.9980	2/2	2/2	2.4 s	415 MB
sharp-mozjpeg-q80	2	0.40 MB → 0.24 MB	39.7%	37.6%	0.9870	0.9778	2/2	1/2	90 ms	109 MB
sharp-webp-q80	2	0.40 MB → 0.21 MB	46.6%	46.2%	0.9853	0.9849	2/2	0/2	75 ms	106 MB
sharp-avif-q50	2	0.40 MB → 0.12 MB	68.6%	70.6%	0.9908	0.9821	2/2	1/2	786 ms	163 MB
sc-fast	2	0.40 MB → 0.04 MB	90.7%	83.3%	1.0000	1.0000	2/2	2/2	505 ms	275 MB

transparent-illustration (4 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	4	0.44 MB → 0.03 MB	92.4%	92.5%	0.9766	0.9751	4/4	0/4	2.8 s	304 MB
sc-balanced-nometa	4	0.44 MB → 0.03 MB	92.4%	92.5%	0.9766	0.9751	4/4	0/4	2.8 s	305 MB
sc-visually-lossless	4	0.44 MB → 0.06 MB	87.0%	86.8%	0.9912	0.9907	4/4	4/4	3.9 s	327 MB
sharp-webp-q80	4	0.44 MB → 0.18 MB	58.0%	58.2%	0.9915	0.9904	4/4	4/4	127 ms	128 MB
sharp-avif-q50	4	0.44 MB → 0.06 MB	87.4%	87.5%	0.9944	0.9938	4/4	4/4	615 ms	161 MB
sc-fast	4	0.44 MB → 0.17 MB	61.9%	61.8%	0.9876	0.9864	4/4	1/4	440 ms	173 MB

gradient (3 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	3	1.61 MB → 0.00 MB	99.8%	99.8%	0.9965	0.9958	3/3	3/3	4.7 s	519 MB
sc-balanced-nometa	3	1.61 MB → 0.00 MB	99.8%	99.8%	0.9965	0.9958	3/3	3/3	4.7 s	523 MB
sc-visually-lossless	3	1.61 MB → 0.00 MB	99.8%	99.8%	0.9965	0.9955	3/3	3/3	6.3 s	549 MB
sharp-mozjpeg-q80	3	1.61 MB → 0.05 MB	97.1%	97.1%	0.9957	0.9955	3/3	3/3	70 ms	115 MB
sharp-webp-q80	3	1.61 MB → 0.03 MB	97.9%	98.3%	0.9962	0.9955	3/3	3/3	98 ms	109 MB
sharp-avif-q50	3	1.61 MB → 0.01 MB	99.3%	99.3%	0.9967	0.9965	3/3	3/3	456 ms	196 MB
sc-fast	3	1.61 MB → 0.02 MB	98.5%	98.9%	0.9952	0.9946	3/3	3/3	935 ms	305 MB

All categories

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time	Median peak RSS
sc-balanced	24	13.25 MB → 5.15 MB	61.2%	80.1%	0.9784	0.9751	24/24	6/24	1.8 s	304 MB
sc-balanced-nometa	24	13.25 MB → 4.45 MB	66.5%	80.1%	0.9784	0.9751	24/24	6/24	1.8 s	305 MB
sc-visually-lossless	24	13.25 MB → 6.41 MB	51.7%	76.2%	0.9915	0.9902	24/24	24/24	2.3 s	327 MB
sharp-mozjpeg-q80	20	12.82 MB → 6.87 MB	46.4%	49.8%	0.9766	0.9304	11/20	8/20	54 ms	106 MB
sharp-webp-q80	24	13.25 MB → 6.50 MB	51.0%	58.6%	0.9805	0.9613	17/24	8/24	59 ms	105 MB
sharp-avif-q50	24	13.25 MB → 3.41 MB	74.3%	78.1%	0.9740	0.9279	11/24	10/24	590 ms	151 MB
sc-fast	24	13.25 MB → 5.49 MB	58.5%	60.9%	0.9847	0.9752	24/24	8/24	425 ms	173 MB

Lossless results by category

Pixel-exact = output decodes to exactly the reference pixels (RGBA) with the same WASM decoders. JPEG inputs are decoded with MozJPEG; libvips' libjpeg-turbo decode differs slightly, so libvips lossless re-encodes of JPEG inputs are not pixel-exact against that reference.

photo

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	10	2.80 MB → 2.04 MB	27.0%	0.0%	10/10	18 ms	103 MB
sharp-png-max	10	2.80 MB → 2.81 MB	-0.7%	-119.6%	0/10	323 ms	110 MB
sharp-webp-lossless	10	2.80 MB → 4.07 MB	-45.4%	-206.5%	10/10	300 ms	127 MB

photo-large

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	3	7.58 MB → 7.58 MB	0.0%	0.0%	3/3	94 ms	209 MB
sharp-png-max	3	7.58 MB → 24.12 MB	-218.4%	-219.2%	0/3	4.4 s	252 MB
sharp-webp-lossless	3	7.58 MB → 32.13 MB	-324.0%	-328.9%	3/3	5.0 s	552 MB

screenshot

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	2	0.44 MB → 0.10 MB	76.2%	77.5%	2/2	2.4 s	323 MB
sharp-png-max	2	0.44 MB → 0.19 MB	56.4%	56.8%	0/2	216 ms	137 MB
sharp-webp-lossless	2	0.44 MB → 0.10 MB	77.1%	78.3%	2/2	532 ms	196 MB

text-graphic

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	2	0.40 MB → 0.04 MB	90.7%	83.4%	2/2	800 ms	219 MB
sharp-png-max	2	0.40 MB → 0.14 MB	64.8%	61.7%	2/2	100 ms	136 MB
sharp-webp-lossless	2	0.40 MB → 0.04 MB	90.8%	83.4%	2/2	55 ms	145 MB

transparent-illustration

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	4	0.44 MB → 0.25 MB	42.3%	42.6%	4/4	996 ms	178 MB
sharp-png-max	4	0.44 MB → 0.17 MB	60.1%	60.1%	0/4	151 ms	113 MB
sharp-webp-lossless	4	0.44 MB → 0.25 MB	43.3%	43.9%	4/4	467 ms	124 MB

gradient

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	3	1.61 MB → 0.54 MB	66.3%	56.6%	3/3	2.9 s	276 MB
sharp-png-max	3	1.61 MB → 0.39 MB	75.8%	64.8%	0/3	209 ms	147 MB
sharp-webp-lossless	3	1.61 MB → 0.64 MB	60.0%	55.9%	3/3	662 ms	175 MB

All categories

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time	Median peak RSS
sc-lossless	24	13.25 MB → 10.55 MB	20.4%	39.7%	24/24	379 ms	178 MB
sharp-png-max	24	13.25 MB → 27.83 MB	-110.0%	50.6%	2/24	231 ms	113 MB
sharp-webp-lossless	24	13.25 MB → 37.22 MB	-180.8%	36.8%	24/24	307 ms	131 MB

Head-to-head per image

A dominates = A is no larger and has SSIM ≥ B on that image. trade-off = one is smaller, the other has higher SSIM.

A	B	images	A dominates	B dominates	trade-off
sc-balanced	sharp-mozjpeg-q80	20	11	0	9
sc-balanced	sharp-webp-q80	24	10	0	14
sc-balanced	sharp-avif-q50	24	2	0	22
sc-balanced-nometa	sharp-mozjpeg-q80	20	11	0	9
sc-balanced-nometa	sharp-webp-q80	24	9	0	15
sc-balanced-nometa	sharp-avif-q50	24	2	0	22
sc-visually-lossless	sharp-mozjpeg-q80	20	5	0	15
sc-visually-lossless	sharp-webp-q80	24	7	0	17
sc-visually-lossless	sharp-avif-q50	24	2	1	21
sc-fast	sharp-mozjpeg-q80	20	6	0	14
sc-fast	sharp-webp-q80	24	7	2	15
sc-fast	sharp-avif-q50	24	2	6	16

Per-image rows

Image	Tool	Bytes	Reduction	SSIM	Format	Time
photo-kodim01.jpg	sc-balanced	80520	52.0%	0.9767	avif	1.1 s
photo-kodim01.jpg	sc-balanced-nometa	80520	52.0%	0.9767	avif	1.1 s
photo-kodim01.jpg	sc-visually-lossless	112366	33.0%	0.9911	avif	1.8 s
photo-kodim01.jpg	sc-lossless	167760	0.0%	1.0000 (exact)	jpeg	18 ms
photo-kodim01.jpg	sharp-mozjpeg-q80	86173	48.6%	0.9566	jpeg	42 ms
photo-kodim01.jpg	sharp-webp-q80	94870	43.4%	0.9792	webp	40 ms
photo-kodim01.jpg	sharp-avif-q50	41843	75.1%	0.9338	avif	589 ms
photo-kodim01.jpg	sharp-png-max	345361	-105.9%	0.9923	png	216 ms
photo-kodim01.jpg	sharp-webp-lossless	431354	-157.1%	1.0000 (exact)	webp	295 ms
photo-kodim03.jpg	sc-balanced	29735	65.8%	0.9767	avif	844 ms
photo-kodim03.jpg	sc-balanced-nometa	29735	65.8%	0.9767	avif	840 ms
photo-kodim03.jpg	sc-visually-lossless	53589	38.4%	0.9908	avif	1.2 s
photo-kodim03.jpg	sc-lossless	86969	0.0%	1.0000 (exact)	jpeg	17 ms
photo-kodim03.jpg	sharp-mozjpeg-q80	42583	51.0%	0.9715	jpeg	29 ms
photo-kodim03.jpg	sharp-webp-q80	32648	62.5%	0.9731	webp	30 ms
photo-kodim03.jpg	sharp-avif-q50	19444	77.6%	0.9661	avif	426 ms
photo-kodim03.jpg	sharp-png-max	228512	-162.8%	0.9779	png	307 ms
photo-kodim03.jpg	sharp-webp-lossless	281922	-224.2%	1.0000 (exact)	webp	336 ms
photo-kodim05.jpg	sc-balanced	78288	54.9%	0.9765	avif	1.1 s
photo-kodim05.jpg	sc-balanced-nometa	78288	54.9%	0.9765	avif	1.1 s
photo-kodim05.jpg	sc-visually-lossless	113870	34.4%	0.9909	avif	1.6 s
photo-kodim05.jpg	sc-lossless	173611	0.0%	1.0000 (exact)	jpeg	19 ms
photo-kodim05.jpg	sharp-mozjpeg-q80	95451	45.0%	0.9711	jpeg	43 ms
photo-kodim05.jpg	sharp-webp-q80	96962	44.1%	0.9801	webp	38 ms
photo-kodim05.jpg	sharp-avif-q50	45199	74.0%	0.9526	avif	649 ms
photo-kodim05.jpg	sharp-png-max	313227	-80.4%	0.9813	png	563 ms
photo-kodim05.jpg	sharp-webp-lossless	511768	-194.8%	1.0000 (exact)	webp	301 ms
photo-kodim07.jpg	sc-balanced	29628	70.2%	0.9756	avif	900 ms
photo-kodim07.jpg	sc-balanced-nometa	29628	70.2%	0.9756	avif	901 ms
photo-kodim07.jpg	sc-visually-lossless	56370	43.3%	0.9910	avif	1.3 s
photo-kodim07.jpg	sc-lossless	99340	0.0%	1.0000 (exact)	jpeg	18 ms
photo-kodim07.jpg	sharp-mozjpeg-q80	52104	47.5%	0.9805	jpeg	31 ms
photo-kodim07.jpg	sharp-webp-q80	40390	59.3%	0.9803	webp	31 ms
photo-kodim07.jpg	sharp-avif-q50	21739	78.1%	0.9720	avif	468 ms
photo-kodim07.jpg	sharp-png-max	250974	-152.6%	0.9868	png	340 ms
photo-kodim07.jpg	sharp-webp-lossless	329526	-231.7%	1.0000 (exact)	webp	302 ms
photo-kodim13.jpg	sc-balanced	110720	45.0%	0.9789	avif	1.2 s
photo-kodim13.jpg	sc-balanced-nometa	110720	45.0%	0.9789	avif	1.2 s
photo-kodim13.jpg	sc-visually-lossless	139224	30.9%	0.9904	avif	2.4 s
photo-kodim13.jpg	sc-lossless	201392	0.0%	1.0000 (exact)	jpeg	17 ms
photo-kodim13.jpg	sharp-mozjpeg-q80	104241	48.2%	0.9487	jpeg	51 ms
photo-kodim13.jpg	sharp-webp-q80	127866	36.5%	0.9808	webp	44 ms
photo-kodim13.jpg	sharp-avif-q50	58958	70.7%	0.9279	avif	702 ms
photo-kodim13.jpg	sharp-png-max	356077	-76.8%	0.9877	png	388 ms
photo-kodim13.jpg	sharp-webp-lossless	523214	-159.8%	1.0000 (exact)	webp	293 ms
photo-kodim15.jpg	sc-balanced	47134	54.2%	0.9786	avif	1.0 s
photo-kodim15.jpg	sc-balanced-nometa	47134	54.2%	0.9786	avif	1.0 s
photo-kodim15.jpg	sc-visually-lossless	69356	32.6%	0.9904	avif	1.4 s
photo-kodim15.jpg	sc-lossless	102888	0.0%	1.0000 (exact)	jpeg	17 ms
photo-kodim15.jpg	sharp-mozjpeg-q80	48942	52.4%	0.9602	jpeg	28 ms
photo-kodim15.jpg	sharp-webp-q80	42636	58.6%	0.9660	webp	31 ms
photo-kodim15.jpg	sharp-avif-q50	23189	77.5%	0.9495	avif	472 ms
photo-kodim15.jpg	sharp-png-max	254599	-147.5%	0.9797	png	358 ms
photo-kodim15.jpg	sharp-webp-lossless	339170	-229.6%	1.0000 (exact)	webp	308 ms
photo-kodim20.jpg	sc-balanced	27632	68.1%	0.9753	avif	808 ms
photo-kodim20.jpg	sc-balanced-nometa	27632	68.1%	0.9753	avif	798 ms
photo-kodim20.jpg	sc-visually-lossless	51201	40.8%	0.9913	avif	1.9 s
photo-kodim20.jpg	sc-lossless	86487	0.0%	1.0000 (exact)	jpeg	19 ms
photo-kodim20.jpg	sharp-mozjpeg-q80	41242	52.3%	0.9696	jpeg	28 ms
photo-kodim20.jpg	sharp-webp-q80	36664	57.6%	0.9746	webp	29 ms
photo-kodim20.jpg	sharp-avif-q50	19040	78.0%	0.9608	avif	482 ms
photo-kodim20.jpg	sharp-png-max	201888	-133.4%	0.9911	png	205 ms
photo-kodim20.jpg	sharp-webp-lossless	275162	-218.2%	1.0000 (exact)	webp	276 ms
photo-kodim23.jpg	sc-balanced	30117	64.5%	0.9782	avif	857 ms
photo-kodim23.jpg	sc-balanced-nometa	30117	64.5%	0.9782	avif	853 ms
photo-kodim23.jpg	sc-visually-lossless	58731	30.8%	0.9917	avif	1.3 s
photo-kodim23.jpg	sc-lossless	84887	0.0%	1.0000 (exact)	jpeg	18 ms
photo-kodim23.jpg	sharp-mozjpeg-q80	40196	52.6%	0.9753	jpeg	27 ms
photo-kodim23.jpg	sharp-webp-q80	30072	64.6%	0.9711	webp	30 ms
photo-kodim23.jpg	sharp-avif-q50	17459	79.4%	0.9671	avif	400 ms
photo-kodim23.jpg	sharp-png-max	212335	-150.1%	0.9522	png	544 ms
photo-kodim23.jpg	sharp-webp-lossless	343038	-304.1%	1.0000 (exact)	webp	295 ms
photo-kodim08.png	sc-balanced	101867	89.8%	0.9774	avif	1.4 s
photo-kodim08.png	sc-balanced-nometa	101867	89.8%	0.9774	avif	1.4 s
photo-kodim08.png	sc-visually-lossless	163585	83.6%	0.9905	avif	2.3 s
photo-kodim08.png	sc-lossless	552370	44.5%	1.0000 (exact)	webp	485 ms
photo-kodim08.png	sharp-mozjpeg-q80	93847	90.6%	0.9572	jpeg	49 ms
photo-kodim08.png	sharp-webp-q80	98826	90.1%	0.9724	webp	42 ms
photo-kodim08.png	sharp-avif-q50	42885	95.7%	0.9424	avif	677 ms
photo-kodim08.png	sharp-png-max	323360	67.5%	0.9870	png	299 ms
photo-kodim08.png	sharp-webp-lossless	547446	45.0%	1.0000 (exact)	webp	299 ms
photo-kodim19.png	sc-balanced	70744	91.1%	0.9758	avif	1.1 s
photo-kodim19.png	sc-balanced-nometa	70744	91.1%	0.9758	avif	1.1 s
photo-kodim19.png	sc-visually-lossless	157150	80.3%	0.9927	avif	2.0 s
photo-kodim19.png	sc-lossless	486068	39.1%	1.0000 (exact)	webp	509 ms
photo-kodim19.png	sharp-mozjpeg-q80	59452	92.6%	0.9531	jpeg	38 ms
photo-kodim19.png	sharp-webp-q80	57400	92.8%	0.9613	webp	39 ms
photo-kodim19.png	sharp-avif-q50	26685	96.7%	0.9403	avif	509 ms
photo-kodim19.png	sharp-png-max	328557	58.9%	0.9891	png	169 ms
photo-kodim19.png	sharp-webp-lossless	483668	39.4%	1.0000 (exact)	webp	307 ms
large-picsum1015.jpg	sc-balanced	1371351	40.0%	0.9842	jpeg	4.5 s
large-picsum1015.jpg	sc-balanced-nometa	1106887	51.6%	0.9791	avif	8.5 s
large-picsum1015.jpg	sc-visually-lossless	1601997	29.9%	0.9936	jpeg	3.8 s
large-picsum1015.jpg	sc-lossless	2285854	0.0%	1.0000 (exact)	jpeg	94 ms
large-picsum1015.jpg	sharp-mozjpeg-q80	1695509	25.8%	0.9958	jpeg	790 ms
large-picsum1015.jpg	sharp-webp-q80	1493726	34.7%	0.9800	webp	836 ms
large-picsum1015.jpg	sharp-avif-q50	813262	64.4%	0.9732	avif	9.5 s
large-picsum1015.jpg	sharp-png-max	7295526	-219.2%	0.9498	png	5.0 s
large-picsum1015.jpg	sharp-webp-lossless	9874632	-332.0%	1.0000 (exact)	webp	5.1 s
large-picsum1043.jpg	sc-balanced	2044901	37.9%	0.9794	jpeg	4.0 s
large-picsum1043.jpg	sc-balanced-nometa	1823943	44.6%	0.9797	avif	11.7 s
large-picsum1043.jpg	sc-visually-lossless	2352615	28.6%	0.9933	jpeg	4.4 s
large-picsum1043.jpg	sc-lossless	3293882	0.0%	1.0000 (exact)	jpeg	103 ms
large-picsum1043.jpg	sharp-mozjpeg-q80	2482091	24.6%	0.9957	jpeg	960 ms
large-picsum1043.jpg	sharp-webp-q80	2481406	24.7%	0.9793	webp	984 ms
large-picsum1043.jpg	sharp-avif-q50	1271025	61.4%	0.9632	avif	10.6 s
large-picsum1043.jpg	sharp-png-max	9879830	-199.9%	0.9728	png	4.4 s
large-picsum1043.jpg	sharp-webp-lossless	13685602	-315.5%	1.0000 (exact)	webp	5.0 s
large-picsum1050.jpg	sc-balanced	1014978	49.2%	0.9752	webp	3.1 s
large-picsum1050.jpg	sc-balanced-nometa	797663	60.1%	0.9753	avif	10.3 s
large-picsum1050.jpg	sc-visually-lossless	1343631	32.7%	0.9917	jpeg	3.4 s
large-picsum1050.jpg	sc-lossless	1997063	0.0%	1.0000 (exact)	jpeg	90 ms
large-picsum1050.jpg	sharp-mozjpeg-q80	1502153	24.8%	0.9964	jpeg	730 ms
large-picsum1050.jpg	sharp-webp-q80	1275176	36.1%	0.9819	webp	785 ms
large-picsum1050.jpg	sharp-avif-q50	732025	63.3%	0.9747	avif	8.2 s
large-picsum1050.jpg	sharp-png-max	6949339	-248.0%	0.9720	png	4.3 s
large-picsum1050.jpg	sharp-webp-lossless	8566208	-328.9%	1.0000 (exact)	webp	4.7 s
screenshot-dashboard.png	sc-balanced	17121	93.2%	0.9819	avif	16.6 s
screenshot-dashboard.png	sc-balanced-nometa	17121	93.2%	0.9819	avif	16.7 s
screenshot-dashboard.png	sc-visually-lossless	17346	93.1%	0.9902	avif	38.6 s
screenshot-dashboard.png	sc-lossless	80542	67.9%	1.0000 (exact)	webp	4.1 s
screenshot-dashboard.png	sharp-mozjpeg-q80	150726	39.9%	0.9934	jpeg	200 ms
screenshot-dashboard.png	sharp-webp-q80	90152	64.0%	0.9982	webp	209 ms
screenshot-dashboard.png	sharp-avif-q50	45836	81.7%	0.9987	avif	2.1 s
screenshot-dashboard.png	sharp-png-max	115208	54.0%	0.9999	png	331 ms
screenshot-dashboard.png	sharp-webp-lossless	76538	69.5%	1.0000 (exact)	webp	1.0 s
screenshot-code.png	sc-balanced	24372	87.2%	1.0000 (exact)	webp	1.7 s
screenshot-code.png	sc-balanced-nometa	24372	87.2%	1.0000 (exact)	webp	1.7 s
screenshot-code.png	sc-visually-lossless	24372	87.2%	1.0000 (exact)	webp	1.9 s
screenshot-code.png	sc-lossless	24372	87.2%	1.0000 (exact)	webp	665 ms
screenshot-code.png	sharp-mozjpeg-q80	88273	53.5%	0.9304	jpeg	64 ms
screenshot-code.png	sharp-webp-q80	73548	61.2%	0.9724	webp	59 ms
screenshot-code.png	sharp-avif-q50	37527	80.2%	0.9915	avif	615 ms
screenshot-code.png	sharp-png-max	76807	59.5%	0.9999	png	101 ms
screenshot-code.png	sharp-webp-lossless	24362	87.2%	1.0000 (exact)	webp	53 ms
text-docs.png	sc-balanced	22230	93.5%	1.0000 (exact)	webp	2.6 s
text-docs.png	sc-balanced-nometa	22230	93.5%	1.0000 (exact)	webp	2.6 s
text-docs.png	sc-visually-lossless	22230	93.5%	1.0000 (exact)	webp	1.7 s
text-docs.png	sc-lossless	22230	93.5%	1.0000 (exact)	webp	928 ms
text-docs.png	sharp-mozjpeg-q80	202724	40.6%	0.9778	jpeg	120 ms
text-docs.png	sharp-webp-q80	181650	46.7%	0.9856	webp	91 ms
text-docs.png	sharp-avif-q50	109850	67.8%	0.9821	avif	1.3 s
text-docs.png	sharp-png-max	115961	66.0%	1.0000 (exact)	png	125 ms
text-docs.png	sharp-webp-lossless	21586	93.7%	1.0000 (exact)	webp	63 ms
text-slide.png	sc-balanced	10195	81.5%	0.9977	avif	1.9 s
text-slide.png	sc-balanced-nometa	10195	81.5%	0.9977	avif	1.8 s
text-slide.png	sc-visually-lossless	9434	82.8%	0.9980	avif	3.0 s
text-slide.png	sc-lossless	14676	73.3%	1.0000 (exact)	webp	672 ms
text-slide.png	sharp-mozjpeg-q80	35945	34.6%	0.9963	jpeg	60 ms
text-slide.png	sharp-webp-q80	29932	45.6%	0.9849	webp	58 ms
text-slide.png	sharp-avif-q50	14595	73.5%	0.9995	avif	317 ms
text-slide.png	sharp-png-max	23467	57.3%	1.0000 (exact)	png	76 ms
text-slide.png	sharp-webp-lossless	14736	73.2%	1.0000 (exact)	webp	46 ms
transparent-illustration-1.png	sc-balanced	9328	92.8%	0.9751	avif	2.8 s
transparent-illustration-1.png	sc-balanced-nometa	9328	92.8%	0.9751	avif	2.8 s
transparent-illustration-1.png	sc-visually-lossless	15701	87.8%	0.9907	avif	3.8 s
transparent-illustration-1.png	sc-lossless	74432	42.2%	1.0000 (exact)	webp	975 ms
transparent-illustration-1.png	sharp-webp-q80	54376	57.8%	0.9904	webp	129 ms
transparent-illustration-1.png	sharp-avif-q50	16236	87.4%	0.9944	avif	591 ms
transparent-illustration-1.png	sharp-png-max	51996	59.6%	0.9935	png	142 ms
transparent-illustration-1.png	sharp-webp-lossless	72962	43.3%	1.0000 (exact)	webp	461 ms
transparent-illustration-2.png	sc-balanced	11976	92.2%	0.9762	avif	2.9 s
transparent-illustration-2.png	sc-balanced-nometa	11976	92.2%	0.9762	avif	2.9 s
transparent-illustration-2.png	sc-visually-lossless	21801	85.8%	0.9913	avif	4.0 s
transparent-illustration-2.png	sc-lossless	87370	43.1%	1.0000 (exact)	webp	1.0 s
transparent-illustration-2.png	sharp-webp-q80	63646	58.5%	0.9920	webp	126 ms
transparent-illustration-2.png	sharp-avif-q50	19146	87.5%	0.9938	avif	645 ms
transparent-illustration-2.png	sharp-png-max	60469	60.6%	0.9948	png	161 ms
transparent-illustration-2.png	sharp-webp-lossless	85216	44.5%	1.0000 (exact)	webp	473 ms
transparent-illustration-3.png	sc-balanced	9623	93.3%	0.9770	avif	2.8 s
transparent-illustration-3.png	sc-balanced-nometa	9623	93.3%	0.9770	avif	2.8 s
transparent-illustration-3.png	sc-visually-lossless	16193	88.7%	0.9911	avif	4.0 s
transparent-illustration-3.png	sc-lossless	85724	40.3%	1.0000 (exact)	webp	1.0 s
transparent-illustration-3.png	sharp-webp-q80	59310	58.7%	0.9911	webp	127 ms
transparent-illustration-3.png	sharp-avif-q50	16459	88.5%	0.9944	avif	639 ms
transparent-illustration-3.png	sharp-png-max	56233	60.9%	0.9946	png	167 ms
transparent-illustration-3.png	sharp-webp-lossless	85228	40.7%	1.0000 (exact)	webp	503 ms
transparent-icon.png	sc-balanced	2147	78.8%	0.9824	avif	803 ms
transparent-icon.png	sc-balanced-nometa	2147	78.8%	0.9824	avif	823 ms
transparent-icon.png	sc-visually-lossless	2836	72.0%	0.9930	avif	1.1 s
transparent-icon.png	sc-lossless	4036	60.1%	1.0000 (exact)	webp	274 ms
transparent-icon.png	sharp-webp-q80	5730	43.4%	0.9970	webp	24 ms
transparent-icon.png	sharp-avif-q50	3248	67.9%	0.9997	avif	115 ms
transparent-icon.png	sharp-png-max	5345	47.2%	1.0000	png	29 ms
transparent-icon.png	sharp-webp-lossless	3972	60.8%	1.0000 (exact)	webp	21 ms
gradient-linear.png	sc-balanced	1413	99.8%	0.9965	avif	4.7 s
gradient-linear.png	sc-balanced-nometa	1413	99.8%	0.9965	avif	4.7 s
gradient-linear.png	sc-visually-lossless	1257	99.8%	0.9966	avif	6.3 s
gradient-linear.png	sc-lossless	120770	84.8%	1.0000 (exact)	webp	2.9 s
gradient-linear.png	sharp-mozjpeg-q80	10930	98.6%	0.9970	jpeg	70 ms
gradient-linear.png	sharp-webp-q80	11860	98.5%	0.9964	webp	99 ms
gradient-linear.png	sharp-avif-q50	4184	99.5%	0.9970	avif	456 ms
gradient-linear.png	sharp-png-max	60759	92.3%	0.9987	png	209 ms
gradient-linear.png	sharp-webp-lossless	112122	85.8%	1.0000 (exact)	webp	662 ms
gradient-radial.png	sc-balanced	1936	99.8%	0.9958	avif	7.4 s
gradient-radial.png	sc-balanced-nometa	1936	99.8%	0.9958	avif	7.5 s
gradient-radial.png	sc-visually-lossless	1825	99.8%	0.9955	avif	9.7 s
gradient-radial.png	sc-lossless	406828	48.1%	1.0000 (exact)	png	3.8 s
gradient-radial.png	sharp-mozjpeg-q80	22807	97.1%	0.9955	jpeg	72 ms
gradient-radial.png	sharp-webp-q80	13266	98.3%	0.9955	webp	98 ms
gradient-radial.png	sharp-avif-q50	5440	99.3%	0.9965	avif	495 ms
gradient-radial.png	sharp-png-max	317877	59.4%	0.9989	png	247 ms
gradient-radial.png	sharp-webp-lossless	516402	34.1%	1.0000 (exact)	webp	759 ms
gradient-sky.png	sc-balanced	499	98.4%	0.9965	avif	4.0 s
gradient-sky.png	sc-balanced-nometa	499	98.4%	0.9965	avif	4.0 s
gradient-sky.png	sc-visually-lossless	497	98.4%	0.9965	avif	6.0 s
gradient-sky.png	sc-lossless	13730	56.6%	1.0000 (exact)	webp	1.3 s
gradient-sky.png	sharp-mozjpeg-q80	12473	60.5%	0.9957	jpeg	56 ms
gradient-sky.png	sharp-webp-q80	8532	73.0%	0.9962	webp	77 ms
gradient-sky.png	sharp-avif-q50	957	97.0%	0.9967	avif	415 ms
gradient-sky.png	sharp-png-max	11117	64.8%	0.9986	png	143 ms
gradient-sky.png	sharp-webp-lossless	13944	55.9%	1.0000 (exact)	webp	467 ms
photo-kodim01.jpg	sc-fast	94870	43.4%	0.9792	webp	302 ms
photo-kodim03.jpg	sc-fast	37610	56.8%	0.9768	webp	269 ms
photo-kodim05.jpg	sc-fast	96962	44.1%	0.9801	webp	416 ms
photo-kodim07.jpg	sc-fast	40390	59.3%	0.9803	webp	289 ms
photo-kodim13.jpg	sc-fast	131122	34.9%	0.9821	webp	391 ms
photo-kodim15.jpg	sc-fast	61022	40.7%	0.9787	webp	294 ms
photo-kodim20.jpg	sc-fast	38504	55.5%	0.9786	webp	224 ms
photo-kodim23.jpg	sc-fast	50799	40.2%	0.9781	jpeg	259 ms
photo-kodim08.png	sc-fast	108162	89.1%	0.9762	webp	382 ms
photo-kodim19.png	sc-fast	110418	86.2%	0.9837	webp	324 ms
large-picsum1015.jpg	sc-fast	1247055	45.4%	0.9779	jpeg	2.6 s
large-picsum1043.jpg	sc-fast	2133327	35.2%	0.9857	jpeg	2.9 s
large-picsum1050.jpg	sc-fast	1014978	49.2%	0.9752	webp	2.4 s
screenshot-dashboard.png	sc-fast	77404	69.1%	1.0000 (exact)	webp	1.4 s
screenshot-code.png	sc-fast	24372	87.2%	1.0000 (exact)	webp	341 ms
text-docs.png	sc-fast	22230	93.5%	1.0000 (exact)	webp	540 ms
text-slide.png	sc-fast	14734	73.2%	1.0000 (exact)	webp	470 ms
transparent-illustration-1.png	sc-fast	49228	61.8%	0.9864	webp	434 ms
transparent-illustration-2.png	sc-fast	57814	62.3%	0.9868	webp	592 ms
transparent-illustration-3.png	sc-fast	54976	61.7%	0.9885	webp	446 ms
transparent-icon.png	sc-fast	4036	60.1%	1.0000 (exact)	webp	100 ms
gradient-linear.png	sc-fast	8297	99.0%	0.9953	jpeg	935 ms
gradient-radial.png	sc-fast	8890	98.9%	0.9946	webp	1.1 s
gradient-sky.png	sc-fast	6456	79.6%	0.9952	webp	635 ms

Browser (Chromium): Optiq vs browser-image-compression and canvas

Environment: {"runtime":"Chromium 156.0.8078.4 (Playwright, headless)","userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/156.0.8078.4 Safari/537.36","platform":"darwin-arm64","date":"2026-10-28T05:27:54.789Z","memory":"not measured in the browser (see Node benchmark for peak RSS)","merged":["2026-10-27T12:10:41.567Z: sc-balanced","2026-10-27T13:08:44.960Z: sc-balanced,sc-visually-lossless,sc-lossless","2026-10-27T14:22:54.348Z: sc-fast","2026-10-28T05:27:54.789Z: sc-fast"]}

Perceptual (lossy) results by category

SSIM is Optiq's metric (8x8 windows, Y/Cb/Cr 6:1:1, active-window pooling), computed identically for every tool against the decoded input. Fixed-quality baselines do not target a quality, so compare size and SSIM.

photo (10 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	10	2.80 MB → 0.61 MB	78.3%	65.2%	0.9767	0.9753	10/10	0/10	910 ms
sc-visually-lossless	10	2.80 MB → 0.98 MB	65.1%	36.4%	0.9909	0.9904	10/10	10/10	1.6 s
bic-maxsize-1mb	10	2.80 MB → 2.25 MB	19.4%	3.5%	0.9962	0.9944	10/10	10/10	11 ms
bic-quality-0.8	10	2.80 MB → 1.83 MB	34.4%	39.7%	0.9748	0.9574	5/10	2/10	4 ms
bic-webp-0.8	10	2.80 MB → 0.66 MB	76.3%	58.5%	0.9742	0.9611	5/10	0/10	22 ms
canvas-webp-0.8	10	2.80 MB → 0.66 MB	76.3%	58.5%	0.9742	0.9611	5/10	0/10	22 ms
canvas-jpeg-0.8	10	2.80 MB → 0.79 MB	71.8%	42.0%	0.9686	0.9574	3/10	0/10	3 ms
sc-fast	10	2.80 MB → 0.77 MB	72.5%	49.8%	0.9789	0.9762	10/10	0/10	249 ms

photo-large (3 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	3	7.58 MB → 4.43 MB	41.5%	40.0%	0.9794	0.9752	3/3	0/3	3.8 s
sc-visually-lossless	3	7.58 MB → 5.30 MB	30.1%	29.9%	0.9933	0.9917	3/3	3/3	3.6 s
bic-maxsize-1mb	3	7.58 MB → 2.80 MB	63.0%	60.0%	–	–	0/3	0/3	405 ms
bic-quality-0.8	3	7.58 MB → 6.33 MB	16.5%	16.5%	0.9963	0.9957	3/3	3/3	70 ms
bic-webp-0.8	3	7.58 MB → 5.24 MB	30.8%	34.7%	0.9799	0.9792	3/3	0/3	616 ms
canvas-webp-0.8	3	7.58 MB → 5.24 MB	30.8%	34.7%	0.9799	0.9792	3/3	0/3	611 ms
canvas-jpeg-0.8	3	7.58 MB → 6.33 MB	16.5%	16.5%	0.9963	0.9957	3/3	3/3	70 ms
sc-fast	3	7.58 MB → 4.40 MB	42.0%	45.4%	0.9779	0.9752	3/3	0/3	2.5 s

screenshot (2 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	2	0.44 MB → 0.04 MB	90.6%	90.2%	0.9910	0.9819	2/2	1/2	8.2 s
sc-visually-lossless	2	0.44 MB → 0.04 MB	90.5%	90.1%	0.9951	0.9902	2/2	2/2	17.2 s
bic-maxsize-1mb	2	0.44 MB → 0.38 MB	14.7%	15.9%	1.0000	1.0000	2/2	2/2	275 ms
bic-quality-0.8	2	0.44 MB → 0.38 MB	14.8%	15.9%	1.0000	1.0000	2/2	2/2	189 ms
bic-webp-0.8	2	0.44 MB → 0.16 MB	62.6%	62.4%	0.9853	0.9723	1/2	1/2	89 ms
canvas-webp-0.8	2	0.44 MB → 0.16 MB	62.6%	62.4%	0.9853	0.9723	1/2	1/2	89 ms
canvas-jpeg-0.8	2	0.44 MB → 0.33 MB	24.7%	26.6%	0.9622	0.9321	1/2	1/2	16 ms
sc-fast	2	0.44 MB → 0.10 MB	76.9%	78.1%	1.0000	1.0000	2/2	2/2	867 ms

text-graphic (2 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	2	0.40 MB → 0.03 MB	91.8%	87.5%	0.9988	0.9977	2/2	2/2	1.7 s
sc-visually-lossless	2	0.40 MB → 0.03 MB	92.0%	88.2%	0.9990	0.9980	2/2	2/2	1.9 s
bic-maxsize-1mb	2	0.40 MB → 0.14 MB	64.4%	61.3%	1.0000	1.0000	2/2	2/2	100 ms
bic-quality-0.8	2	0.40 MB → 0.14 MB	64.4%	61.3%	1.0000	1.0000	2/2	2/2	77 ms
bic-webp-0.8	2	0.40 MB → 0.21 MB	46.3%	45.6%	0.9852	0.9849	2/2	0/2	49 ms
canvas-webp-0.8	2	0.40 MB → 0.21 MB	46.3%	45.6%	0.9852	0.9849	2/2	0/2	49 ms
canvas-jpeg-0.8	2	0.40 MB → 0.32 MB	18.7%	13.4%	0.9834	0.9708	1/2	1/2	7 ms
sc-fast	2	0.40 MB → 0.04 MB	90.7%	83.3%	1.0000	1.0000	2/2	2/2	410 ms

transparent-illustration (4 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	4	0.44 MB → 0.03 MB	92.4%	92.5%	0.9766	0.9751	4/4	0/4	2.2 s
sc-visually-lossless	4	0.44 MB → 0.06 MB	87.0%	86.8%	0.9912	0.9907	4/4	4/4	3.3 s
bic-maxsize-1mb	4	0.44 MB → 0.34 MB	22.1%	23.2%	0.9998	0.9998	4/4	4/4	132 ms
bic-quality-0.8	4	0.44 MB → 0.33 MB	24.5%	25.4%	0.9997	0.9997	4/4	4/4	103 ms
bic-webp-0.8	4	0.44 MB → 0.21 MB	52.8%	52.8%	0.9915	0.9903	4/4	4/4	74 ms
canvas-webp-0.8	4	0.44 MB → 0.21 MB	52.8%	52.8%	0.9915	0.9903	4/4	4/4	74 ms
sc-fast	4	0.44 MB → 0.17 MB	61.9%	61.8%	0.9876	0.9864	4/4	1/4	351 ms

gradient (3 images)

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	3	1.61 MB → 0.00 MB	99.8%	99.8%	0.9965	0.9958	3/3	3/3	4.0 s
sc-visually-lossless	3	1.61 MB → 0.00 MB	99.8%	99.8%	0.9965	0.9955	3/3	3/3	5.4 s
bic-maxsize-1mb	3	1.61 MB → 1.22 MB	23.9%	12.1%	1.0000	0.9999	3/3	3/3	323 ms
bic-quality-0.8	3	1.61 MB → 1.20 MB	25.1%	12.1%	1.0000	0.9999	3/3	3/3	318 ms
bic-webp-0.8	3	1.61 MB → 0.03 MB	97.8%	98.3%	0.9962	0.9955	3/3	3/3	51 ms
canvas-webp-0.8	3	1.61 MB → 0.03 MB	97.8%	98.3%	0.9962	0.9955	3/3	3/3	50 ms
canvas-jpeg-0.8	3	1.61 MB → 0.07 MB	95.5%	96.1%	0.9961	0.9956	3/3	3/3	9 ms
sc-fast	3	1.61 MB → 0.02 MB	98.5%	98.9%	0.9952	0.9946	3/3	3/3	734 ms

All categories

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Median SSIM	Min SSIM	SSIM ≥ 0.975	SSIM ≥ 0.99	Median time
sc-balanced	24	13.25 MB → 5.15 MB	61.2%	80.1%	0.9784	0.9751	24/24	6/24	1.3 s
sc-visually-lossless	24	13.25 MB → 6.41 MB	51.7%	76.2%	0.9915	0.9902	24/24	24/24	2.2 s
bic-maxsize-1mb	24	13.25 MB → 7.14 MB	46.1%	20.5%	0.9998	0.9944	21/24	21/24	128 ms
bic-quality-0.8	24	13.25 MB → 10.21 MB	22.9%	35.6%	0.9977	0.9574	19/24	16/24	78 ms
bic-webp-0.8	24	13.25 MB → 6.52 MB	50.8%	55.5%	0.9804	0.9611	18/24	8/24	37 ms
canvas-webp-0.8	24	13.25 MB → 6.52 MB	50.8%	55.5%	0.9804	0.9611	18/24	8/24	36 ms
canvas-jpeg-0.8	20	12.82 MB → 7.84 MB	38.8%	39.7%	0.9768	0.9321	11/20	8/20	5 ms
sc-fast	24	13.25 MB → 5.49 MB	58.5%	60.9%	0.9847	0.9752	24/24	8/24	349 ms

Lossless results by category

Pixel-exact = output decodes to exactly the reference pixels (RGBA) with the same WASM decoders. JPEG inputs are decoded with MozJPEG; libvips' libjpeg-turbo decode differs slightly, so libvips lossless re-encodes of JPEG inputs are not pixel-exact against that reference.

photo

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	10	2.80 MB → 2.04 MB	27.0%	0.0%	10/10	11 ms

photo-large

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	3	7.58 MB → 7.58 MB	0.0%	0.0%	3/3	104 ms

screenshot

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	2	0.44 MB → 0.10 MB	76.2%	77.5%	2/2	1.4 s

text-graphic

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	2	0.40 MB → 0.04 MB	90.7%	83.4%	2/2	538 ms

transparent-illustration

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	4	0.44 MB → 0.25 MB	42.3%	42.6%	4/4	647 ms

gradient

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	3	1.61 MB → 0.54 MB	66.3%	56.6%	3/3	2.4 s

All categories

Tool	n	Total bytes (in → out)	Total reduction	Median reduction	Pixel-exact	Median time
sc-lossless	24	13.25 MB → 10.55 MB	20.4%	39.7%	24/24	248 ms

Head-to-head per image

A dominates = A is no larger and has SSIM ≥ B on that image. trade-off = one is smaller, the other has higher SSIM.

A	B	images	A dominates	B dominates	trade-off
sc-balanced	bic-maxsize-1mb	21	2	0	19
sc-balanced	bic-quality-0.8	24	9	0	15
sc-balanced	bic-webp-0.8	24	10	0	14
sc-balanced	canvas-webp-0.8	24	10	0	14
sc-balanced	canvas-jpeg-0.8	20	14	0	6
sc-visually-lossless	bic-maxsize-1mb	21	2	0	19
sc-visually-lossless	bic-quality-0.8	24	3	0	21
sc-visually-lossless	bic-webp-0.8	24	8	0	16
sc-visually-lossless	canvas-webp-0.8	24	8	0	16
sc-visually-lossless	canvas-jpeg-0.8	20	5	0	15
sc-fast	bic-maxsize-1mb	21	5	0	16
sc-fast	bic-quality-0.8	24	9	0	15
sc-fast	bic-webp-0.8	24	9	0	15
sc-fast	canvas-webp-0.8	24	9	0	15
sc-fast	canvas-jpeg-0.8	20	9	0	11

Per-image rows

Image	Tool	Bytes	Reduction	SSIM	Format	Time
photo-kodim01.jpg	sc-balanced	80520	52.0%	0.9767	avif	989 ms
photo-kodim01.jpg	sc-visually-lossless	112366	33.0%	0.9911	avif	1.7 s
photo-kodim01.jpg	sc-lossless	167760	0.0%	1.0000 (exact)	jpeg	14 ms
photo-kodim01.jpg	bic-maxsize-1mb	161883	3.5%	0.9953	jpeg	19 ms
photo-kodim01.jpg	bic-quality-0.8	100249	40.2%	0.9633	jpeg	4 ms
photo-kodim01.jpg	bic-webp-0.8	95310	43.2%	0.9791	webp	28 ms
photo-kodim01.jpg	canvas-webp-0.8	95310	43.2%	0.9791	webp	27 ms
photo-kodim01.jpg	canvas-jpeg-0.8	100249	40.2%	0.9633	jpeg	3 ms
photo-kodim03.jpg	sc-balanced	29735	65.8%	0.9767	avif	713 ms
photo-kodim03.jpg	sc-visually-lossless	53589	38.4%	0.9908	avif	1.1 s
photo-kodim03.jpg	sc-lossless	86969	0.0%	1.0000 (exact)	jpeg	10 ms
photo-kodim03.jpg	bic-maxsize-1mb	84173	3.2%	0.9962	jpeg	9 ms
photo-kodim03.jpg	bic-quality-0.8	50906	41.5%	0.9763	jpeg	3 ms
photo-kodim03.jpg	bic-webp-0.8	33034	62.0%	0.9728	webp	20 ms
photo-kodim03.jpg	canvas-webp-0.8	33034	62.0%	0.9728	webp	19 ms
photo-kodim03.jpg	canvas-jpeg-0.8	50906	41.5%	0.9763	jpeg	3 ms
photo-kodim05.jpg	sc-balanced	78288	54.9%	0.9765	avif	939 ms
photo-kodim05.jpg	sc-visually-lossless	113870	34.4%	0.9909	avif	1.5 s
photo-kodim05.jpg	sc-lossless	173611	0.0%	1.0000 (exact)	jpeg	12 ms
photo-kodim05.jpg	bic-maxsize-1mb	167535	3.5%	0.9958	jpeg	12 ms
photo-kodim05.jpg	bic-quality-0.8	109512	36.9%	0.9732	jpeg	4 ms
photo-kodim05.jpg	bic-webp-0.8	97434	43.9%	0.9800	webp	27 ms
photo-kodim05.jpg	canvas-webp-0.8	97434	43.9%	0.9800	webp	27 ms
photo-kodim05.jpg	canvas-jpeg-0.8	109512	36.9%	0.9732	jpeg	4 ms
photo-kodim07.jpg	sc-balanced	29628	70.2%	0.9756	avif	764 ms
photo-kodim07.jpg	sc-visually-lossless	56370	43.3%	0.9910	avif	1.2 s
photo-kodim07.jpg	sc-lossless	99340	0.0%	1.0000 (exact)	jpeg	11 ms
photo-kodim07.jpg	bic-maxsize-1mb	96358	3.0%	0.9968	jpeg	10 ms
photo-kodim07.jpg	bic-quality-0.8	60362	39.2%	0.9814	jpeg	3 ms
photo-kodim07.jpg	bic-webp-0.8	40760	59.0%	0.9801	webp	20 ms
photo-kodim07.jpg	canvas-webp-0.8	40760	59.0%	0.9801	webp	20 ms
photo-kodim07.jpg	canvas-jpeg-0.8	60362	39.2%	0.9814	jpeg	3 ms
photo-kodim13.jpg	sc-balanced	110720	45.0%	0.9789	avif	1.1 s
photo-kodim13.jpg	sc-visually-lossless	139224	30.9%	0.9904	avif	2.2 s
photo-kodim13.jpg	sc-lossless	201392	0.0%	1.0000 (exact)	jpeg	11 ms
photo-kodim13.jpg	bic-maxsize-1mb	193401	4.0%	0.9944	jpeg	16 ms
photo-kodim13.jpg	bic-quality-0.8	123703	38.6%	0.9574	jpeg	4 ms
photo-kodim13.jpg	bic-webp-0.8	128256	36.3%	0.9807	webp	29 ms
photo-kodim13.jpg	canvas-webp-0.8	128256	36.3%	0.9807	webp	29 ms
photo-kodim13.jpg	canvas-jpeg-0.8	123703	38.6%	0.9574	jpeg	4 ms
photo-kodim15.jpg	sc-balanced	47134	54.2%	0.9786	avif	882 ms
photo-kodim15.jpg	sc-visually-lossless	69356	32.6%	0.9904	avif	1.3 s
photo-kodim15.jpg	sc-lossless	102888	0.0%	1.0000 (exact)	jpeg	11 ms
photo-kodim15.jpg	bic-maxsize-1mb	99200	3.6%	0.9950	jpeg	10 ms
photo-kodim15.jpg	bic-quality-0.8	57683	43.9%	0.9645	jpeg	4 ms
photo-kodim15.jpg	bic-webp-0.8	43088	58.1%	0.9664	webp	20 ms
photo-kodim15.jpg	canvas-webp-0.8	43088	58.1%	0.9664	webp	20 ms
photo-kodim15.jpg	canvas-jpeg-0.8	57683	43.9%	0.9645	jpeg	3 ms
photo-kodim20.jpg	sc-balanced	27632	68.1%	0.9753	avif	672 ms
photo-kodim20.jpg	sc-visually-lossless	51201	40.8%	0.9913	avif	1.8 s
photo-kodim20.jpg	sc-lossless	86487	0.0%	1.0000 (exact)	jpeg	10 ms
photo-kodim20.jpg	bic-maxsize-1mb	83674	3.3%	0.9962	jpeg	10 ms
photo-kodim20.jpg	bic-quality-0.8	49624	42.6%	0.9727	jpeg	3 ms
photo-kodim20.jpg	bic-webp-0.8	37106	57.1%	0.9756	webp	18 ms
photo-kodim20.jpg	canvas-webp-0.8	37106	57.1%	0.9756	webp	18 ms
photo-kodim20.jpg	canvas-jpeg-0.8	49624	42.6%	0.9727	jpeg	2 ms
photo-kodim23.jpg	sc-balanced	30117	64.5%	0.9782	avif	717 ms
photo-kodim23.jpg	sc-visually-lossless	58731	30.8%	0.9917	avif	1.2 s
photo-kodim23.jpg	sc-lossless	84887	0.0%	1.0000 (exact)	jpeg	9 ms
photo-kodim23.jpg	bic-maxsize-1mb	82458	2.9%	0.9962	jpeg	9 ms
photo-kodim23.jpg	bic-quality-0.8	47346	44.2%	0.9773	jpeg	3 ms
photo-kodim23.jpg	bic-webp-0.8	30576	64.0%	0.9713	webp	19 ms
photo-kodim23.jpg	canvas-webp-0.8	30576	64.0%	0.9713	webp	20 ms
photo-kodim23.jpg	canvas-jpeg-0.8	47346	44.2%	0.9773	jpeg	2 ms
photo-kodim08.png	sc-balanced	101867	89.8%	0.9774	avif	1.3 s
photo-kodim08.png	sc-visually-lossless	163585	83.6%	0.9905	avif	2.2 s
photo-kodim08.png	sc-lossless	552370	44.5%	1.0000 (exact)	webp	397 ms
photo-kodim08.png	bic-maxsize-1mb	683137	31.3%	0.9977	png	306 ms
photo-kodim08.png	bic-quality-0.8	653365	34.3%	0.9972	png	276 ms
photo-kodim08.png	bic-webp-0.8	99204	90.0%	0.9722	webp	28 ms
photo-kodim08.png	canvas-webp-0.8	99204	90.0%	0.9722	webp	27 ms
photo-kodim08.png	canvas-jpeg-0.8	114041	88.5%	0.9624	jpeg	5 ms
photo-kodim19.png	sc-balanced	70744	91.1%	0.9758	avif	985 ms
photo-kodim19.png	sc-visually-lossless	157150	80.3%	0.9927	avif	1.9 s
photo-kodim19.png	sc-lossless	486068	39.1%	1.0000 (exact)	webp	399 ms
photo-kodim19.png	bic-maxsize-1mb	602938	24.5%	0.9986	png	227 ms
photo-kodim19.png	bic-quality-0.8	581179	27.2%	0.9982	png	214 ms
photo-kodim19.png	bic-webp-0.8	57706	92.8%	0.9611	webp	24 ms
photo-kodim19.png	canvas-webp-0.8	57706	92.8%	0.9611	webp	23 ms
photo-kodim19.png	canvas-jpeg-0.8	74127	90.7%	0.9596	jpeg	5 ms
large-picsum1015.jpg	sc-balanced	1371351	40.0%	0.9842	jpeg	4.3 s
large-picsum1015.jpg	sc-visually-lossless	1601997	29.9%	0.9936	jpeg	3.6 s
large-picsum1015.jpg	sc-lossless	2285854	0.0%	1.0000 (exact)	jpeg	104 ms
large-picsum1015.jpg	bic-maxsize-1mb	914605	60.0%	n/a	jpeg	405 ms
large-picsum1015.jpg	bic-quality-0.8	1898949	16.9%	0.9963	jpeg	70 ms
large-picsum1015.jpg	bic-webp-0.8	1492218	34.7%	0.9799	webp	616 ms
large-picsum1015.jpg	canvas-webp-0.8	1492218	34.7%	0.9799	webp	611 ms
large-picsum1015.jpg	canvas-jpeg-0.8	1898949	16.9%	0.9963	jpeg	70 ms
large-picsum1043.jpg	sc-balanced	2044901	37.9%	0.9794	jpeg	3.8 s
large-picsum1043.jpg	sc-visually-lossless	2352615	28.6%	0.9933	jpeg	4.2 s
large-picsum1043.jpg	sc-lossless	3293882	0.0%	1.0000 (exact)	jpeg	113 ms
large-picsum1043.jpg	bic-maxsize-1mb	855267	74.0%	n/a	jpeg	526 ms
large-picsum1043.jpg	bic-quality-0.8	2761314	16.2%	0.9957	jpeg	85 ms
large-picsum1043.jpg	bic-webp-0.8	2475888	24.8%	0.9792	webp	755 ms
large-picsum1043.jpg	canvas-webp-0.8	2475888	24.8%	0.9792	webp	758 ms
large-picsum1043.jpg	canvas-jpeg-0.8	2761314	16.2%	0.9957	jpeg	83 ms
large-picsum1050.jpg	sc-balanced	1014978	49.2%	0.9752	webp	3.0 s
large-picsum1050.jpg	sc-visually-lossless	1343631	32.7%	0.9917	jpeg	3.2 s
large-picsum1050.jpg	sc-lossless	1997063	0.0%	1.0000 (exact)	jpeg	100 ms
large-picsum1050.jpg	bic-maxsize-1mb	1034853	48.2%	n/a	jpeg	363 ms
large-picsum1050.jpg	bic-quality-0.8	1668231	16.5%	0.9964	jpeg	68 ms
large-picsum1050.jpg	bic-webp-0.8	1273684	36.2%	0.9818	webp	594 ms
large-picsum1050.jpg	canvas-webp-0.8	1273684	36.2%	0.9818	webp	588 ms
large-picsum1050.jpg	canvas-jpeg-0.8	1668231	16.5%	0.9964	jpeg	68 ms
screenshot-dashboard.png	sc-balanced	17121	93.2%	0.9819	avif	15.2 s
screenshot-dashboard.png	sc-visually-lossless	17346	93.1%	0.9902	avif	33.1 s
screenshot-dashboard.png	sc-lossless	80542	67.9%	1.0000 (exact)	webp	2.5 s
screenshot-dashboard.png	bic-maxsize-1mb	231623	7.6%	1.0000	png	426 ms
screenshot-dashboard.png	bic-quality-0.8	231608	7.6%	1.0000	png	281 ms
screenshot-dashboard.png	bic-webp-0.8	90548	63.9%	0.9982	webp	140 ms
screenshot-dashboard.png	canvas-webp-0.8	90548	63.9%	0.9982	webp	140 ms
screenshot-dashboard.png	canvas-jpeg-0.8	218398	12.9%	0.9923	jpeg	26 ms
screenshot-code.png	sc-balanced	24372	87.2%	1.0000 (exact)	webp	1.2 s
screenshot-code.png	sc-visually-lossless	24372	87.2%	1.0000 (exact)	webp	1.3 s
screenshot-code.png	sc-lossless	24372	87.2%	1.0000 (exact)	webp	362 ms
screenshot-code.png	bic-maxsize-1mb	143773	24.2%	1.0000	png	125 ms
screenshot-code.png	bic-quality-0.8	143763	24.2%	1.0000	png	96 ms
screenshot-code.png	bic-webp-0.8	74006	61.0%	0.9723	webp	39 ms
screenshot-code.png	canvas-webp-0.8	74006	61.0%	0.9723	webp	37 ms
screenshot-code.png	canvas-jpeg-0.8	113286	40.3%	0.9321	jpeg	6 ms
text-docs.png	sc-balanced	22230	93.5%	1.0000 (exact)	webp	2.1 s
text-docs.png	sc-visually-lossless	22230	93.5%	1.0000 (exact)	webp	1.3 s
text-docs.png	sc-lossless	22230	93.5%	1.0000 (exact)	webp	641 ms
text-docs.png	bic-maxsize-1mb	117407	65.6%	1.0000	png	124 ms
text-docs.png	bic-quality-0.8	117402	65.6%	1.0000	png	86 ms
text-docs.png	bic-webp-0.8	182110	46.6%	0.9855	webp	63 ms
text-docs.png	canvas-webp-0.8	182110	46.6%	0.9855	webp	62 ms
text-docs.png	canvas-jpeg-0.8	270394	20.7%	0.9708	jpeg	10 ms
text-slide.png	sc-balanced	10195	81.5%	0.9977	avif	1.4 s
text-slide.png	sc-visually-lossless	9434	82.8%	0.9980	avif	2.4 s
text-slide.png	sc-lossless	14676	73.3%	1.0000 (exact)	webp	436 ms
text-slide.png	bic-maxsize-1mb	23681	56.9%	1.0000 (exact)	png	77 ms
text-slide.png	bic-quality-0.8	23681	56.9%	1.0000 (exact)	png	69 ms
text-slide.png	bic-webp-0.8	30438	44.6%	0.9849	webp	35 ms
text-slide.png	canvas-webp-0.8	30438	44.6%	0.9849	webp	35 ms
text-slide.png	canvas-jpeg-0.8	51663	6.0%	0.9961	jpeg	5 ms
transparent-illustration-1.png	sc-balanced	9328	92.8%	0.9751	avif	2.2 s
transparent-illustration-1.png	sc-visually-lossless	15701	87.8%	0.9907	avif	3.2 s
transparent-illustration-1.png	sc-lossless	74432	42.2%	1.0000 (exact)	webp	630 ms
transparent-illustration-1.png	bic-maxsize-1mb	99735	22.5%	0.9999	png	142 ms
transparent-illustration-1.png	bic-quality-0.8	96692	24.9%	0.9997	png	115 ms
transparent-illustration-1.png	bic-webp-0.8	62314	51.6%	0.9903	webp	74 ms
transparent-illustration-1.png	canvas-webp-0.8	62314	51.6%	0.9903	webp	73 ms
transparent-illustration-2.png	sc-balanced	11976	92.2%	0.9762	avif	2.3 s
transparent-illustration-2.png	sc-visually-lossless	21801	85.8%	0.9913	avif	3.4 s
transparent-illustration-2.png	sc-lossless	87370	43.1%	1.0000 (exact)	webp	664 ms
transparent-illustration-2.png	bic-maxsize-1mb	117019	23.8%	0.9998	png	133 ms
transparent-illustration-2.png	bic-quality-0.8	113683	25.9%	0.9997	png	103 ms
transparent-illustration-2.png	bic-webp-0.8	70726	53.9%	0.9920	webp	77 ms
transparent-illustration-2.png	canvas-webp-0.8	70726	53.9%	0.9920	webp	77 ms
transparent-illustration-3.png	sc-balanced	9623	93.3%	0.9770	avif	2.3 s
transparent-illustration-3.png	sc-visually-lossless	16193	88.7%	0.9911	avif	3.5 s
transparent-illustration-3.png	sc-lossless	85724	40.3%	1.0000 (exact)	webp	693 ms
transparent-illustration-3.png	bic-maxsize-1mb	117051	18.5%	0.9998	png	131 ms
transparent-illustration-3.png	bic-quality-0.8	112819	21.5%	0.9997	png	102 ms
transparent-illustration-3.png	bic-webp-0.8	66168	54.0%	0.9911	webp	74 ms
transparent-illustration-3.png	canvas-webp-0.8	66168	54.0%	0.9911	webp	75 ms
transparent-icon.png	sc-balanced	2147	78.8%	0.9824	avif	547 ms
transparent-icon.png	sc-visually-lossless	2836	72.0%	0.9930	avif	774 ms
transparent-icon.png	sc-lossless	4036	60.1%	1.0000 (exact)	webp	134 ms
transparent-icon.png	bic-maxsize-1mb	6095	39.8%	1.0000	png	24 ms
transparent-icon.png	bic-quality-0.8	6095	39.8%	1.0000	png	16 ms
transparent-icon.png	bic-webp-0.8	6548	35.3%	0.9970	webp	9 ms
transparent-icon.png	canvas-webp-0.8	6548	35.3%	0.9970	webp	9 ms
gradient-linear.png	sc-balanced	1413	99.8%	0.9965	avif	4.0 s
gradient-linear.png	sc-visually-lossless	1257	99.8%	0.9966	avif	5.4 s
gradient-linear.png	sc-lossless	120770	84.8%	1.0000 (exact)	webp	2.4 s
gradient-linear.png	bic-maxsize-1mb	425438	46.3%	1.0000	png	323 ms
gradient-linear.png	bic-quality-0.8	425438	46.3%	1.0000	png	318 ms
gradient-linear.png	bic-webp-0.8	12380	98.4%	0.9964	webp	58 ms
gradient-linear.png	canvas-webp-0.8	12380	98.4%	0.9964	webp	59 ms
gradient-linear.png	canvas-jpeg-0.8	17966	97.7%	0.9969	jpeg	9 ms
gradient-radial.png	sc-balanced	1936	99.8%	0.9958	avif	6.3 s
gradient-radial.png	sc-visually-lossless	1825	99.8%	0.9955	avif	8.4 s
gradient-radial.png	sc-lossless	406828	48.1%	1.0000 (exact)	png	3.2 s
gradient-radial.png	bic-maxsize-1mb	770935	1.6%	0.9999	png	3.9 s
gradient-radial.png	bic-quality-0.8	750416	4.3%	0.9999	png	3.4 s
gradient-radial.png	bic-webp-0.8	13628	98.3%	0.9955	webp	51 ms
gradient-radial.png	canvas-webp-0.8	13628	98.3%	0.9955	webp	50 ms
gradient-radial.png	canvas-jpeg-0.8	30640	96.1%	0.9956	jpeg	9 ms
gradient-sky.png	sc-balanced	499	98.4%	0.9965	avif	3.0 s
gradient-sky.png	sc-visually-lossless	497	98.4%	0.9965	avif	5.0 s
gradient-sky.png	sc-lossless	13730	56.6%	1.0000 (exact)	webp	756 ms
gradient-sky.png	bic-maxsize-1mb	27780	12.1%	1.0000 (exact)	png	191 ms
gradient-sky.png	bic-quality-0.8	27780	12.1%	1.0000 (exact)	png	189 ms
gradient-sky.png	bic-webp-0.8	8896	71.8%	0.9962	webp	45 ms
gradient-sky.png	canvas-webp-0.8	8896	71.8%	0.9962	webp	45 ms
gradient-sky.png	canvas-jpeg-0.8	23224	26.5%	0.9961	jpeg	6 ms
photo-kodim01.jpg	sc-fast	94870	43.4%	0.9792	webp	292 ms
photo-kodim03.jpg	sc-fast	37610	56.8%	0.9768	webp	217 ms
photo-kodim05.jpg	sc-fast	96962	44.1%	0.9801	webp	348 ms
photo-kodim07.jpg	sc-fast	40390	59.3%	0.9803	webp	222 ms
photo-kodim13.jpg	sc-fast	131122	34.9%	0.9821	webp	335 ms
photo-kodim15.jpg	sc-fast	61022	40.7%	0.9787	webp	228 ms
photo-kodim20.jpg	sc-fast	38504	55.5%	0.9786	webp	168 ms
photo-kodim23.jpg	sc-fast	50799	40.2%	0.9781	jpeg	203 ms
photo-kodim08.png	sc-fast	108162	89.1%	0.9762	webp	316 ms
photo-kodim19.png	sc-fast	110418	86.2%	0.9837	webp	270 ms
large-picsum1015.jpg	sc-fast	1247055	45.4%	0.9779	jpeg	2.5 s
large-picsum1043.jpg	sc-fast	2133327	35.2%	0.9857	jpeg	2.8 s
large-picsum1050.jpg	sc-fast	1014978	49.2%	0.9752	webp	2.3 s
screenshot-dashboard.png	sc-fast	77404	69.1%	1.0000 (exact)	webp	1.4 s
screenshot-code.png	sc-fast	24372	87.2%	1.0000 (exact)	webp	292 ms
text-docs.png	sc-fast	22230	93.5%	1.0000 (exact)	webp	470 ms
text-slide.png	sc-fast	14734	73.2%	1.0000 (exact)	webp	349 ms
transparent-illustration-1.png	sc-fast	49228	61.8%	0.9864	webp	352 ms
transparent-illustration-2.png	sc-fast	57814	62.3%	0.9868	webp	503 ms
transparent-illustration-3.png	sc-fast	54976	61.7%	0.9885	webp	350 ms
transparent-icon.png	sc-fast	4036	60.1%	1.0000 (exact)	webp	49 ms
gradient-linear.png	sc-fast	8297	99.0%	0.9953	jpeg	734 ms
gradient-radial.png	sc-fast	8890	98.9%	0.9946	webp	829 ms
gradient-sky.png	sc-fast	6456	79.6%	0.9952	webp	480 ms

Optimisation log: tile-mosaic proxy search (Node)

v0 searched quality with full-resolution encodes. v1 searches on a 3x3 mosaic of 512 px full-resolution tiles for images above 4 MP and verifies only the finalists at full size; balanced rows additionally use AVIF speed 7 instead of 8 (see docs/architecture.md). Same corpus, same machine; v0 data: bench/results/node-v0-before-proxy.json.

Image	Tool	Bytes v0 → v1	SSIM v0 → v1	Time v0 → v1	Peak RSS v0 → v1
photo-kodim13.jpg	sc-visually-lossless	139224 → 139224 (0.0%)	0.9904 → 0.9904	2.2 s → 2.4 s	220 MB → 223 MB
photo-kodim08.png	sc-visually-lossless	163585 → 163585 (0.0%)	0.9905 → 0.9905	2.1 s → 2.3 s	225 MB → 227 MB
photo-kodim19.png	sc-visually-lossless	141333 → 157150 (11.2%)	0.9913 → 0.9927	2.3 s → 2.0 s	232 MB → 237 MB
large-picsum1015.jpg	sc-balanced	1298804 → 1371351 (5.6%)	0.9757 → 0.9842	9.9 s → 4.5 s	769 MB → 772 MB
large-picsum1015.jpg	sc-balanced-nometa	1089255 → 1106887 (1.6%)	0.9775 → 0.9791	17.6 s → 8.5 s	1373 MB → 929 MB
large-picsum1015.jpg	sc-visually-lossless	1601997 → 1601997 (0.0%)	0.9936 → 0.9936	11.1 s → 3.8 s	883 MB → 594 MB
large-picsum1043.jpg	sc-balanced	2044901 → 2044901 (0.0%)	0.9794 → 0.9794	10.6 s → 4.0 s	821 MB → 584 MB
large-picsum1043.jpg	sc-balanced-nometa	1786000 → 1823943 (2.1%)	0.9753 → 0.9797	20.2 s → 11.7 s	1412 MB → 971 MB
large-picsum1043.jpg	sc-visually-lossless	2352615 → 2352615 (0.0%)	0.9933 → 0.9933	13.2 s → 4.4 s	932 MB → 613 MB
large-picsum1050.jpg	sc-balanced	1014978 → 1014978 (0.0%)	0.9752 → 0.9752	9.6 s → 3.1 s	763 MB → 534 MB
large-picsum1050.jpg	sc-balanced-nometa	1045781 → 797663 (-23.7%)	0.9760 → 0.9753	20.0 s → 10.3 s	1339 MB → 936 MB
large-picsum1050.jpg	sc-visually-lossless	1343631 → 1343631 (0.0%)	0.9917 → 0.9917	10.8 s → 3.4 s	868 MB → 590 MB
screenshot-dashboard.png	sc-balanced	45068 → 17121 (-62.0%)	0.9787 → 0.9819	7.9 s → 16.6 s	947 MB → 1041 MB
screenshot-dashboard.png	sc-balanced-nometa	45068 → 17121 (-62.0%)	0.9787 → 0.9819	7.9 s → 16.7 s	947 MB → 837 MB
screenshot-dashboard.png	sc-visually-lossless	17346 → 17346 (0.0%)	0.9902 → 0.9902	56.4 s → 38.6 s	1129 MB → 978 MB
text-docs.png	sc-balanced	22230 → 22230 (0.0%)	1.0000 → 1.0000	2.3 s → 2.6 s	407 MB → 416 MB
text-docs.png	sc-balanced-nometa	22230 → 22230 (0.0%)	1.0000 → 1.0000	2.3 s → 2.6 s	411 MB → 412 MB
text-slide.png	sc-visually-lossless	9434 → 9434 (0.0%)	0.9980 → 0.9980	3.0 s → 3.0 s	419 MB → 424 MB
transparent-illustration-1.png	sc-balanced	11941 → 9328 (-21.9%)	0.9755 → 0.9751	2.4 s → 2.8 s	301 MB → 301 MB
transparent-illustration-1.png	sc-balanced-nometa	11941 → 9328 (-21.9%)	0.9755 → 0.9751	2.4 s → 2.8 s	300 MB → 302 MB
transparent-illustration-1.png	sc-visually-lossless	14366 → 15701 (9.3%)	0.9902 → 0.9907	3.7 s → 3.8 s	314 MB → 326 MB
transparent-illustration-2.png	sc-balanced	14416 → 11976 (-16.9%)	0.9774 → 0.9762	2.4 s → 2.9 s	301 MB → 306 MB
transparent-illustration-2.png	sc-balanced-nometa	14416 → 11976 (-16.9%)	0.9774 → 0.9762	2.4 s → 2.9 s	303 MB → 309 MB
transparent-illustration-2.png	sc-visually-lossless	19979 → 21801 (9.1%)	0.9910 → 0.9913	3.9 s → 4.0 s	322 MB → 327 MB
transparent-illustration-3.png	sc-balanced	10809 → 9623 (-11.0%)	0.9761 → 0.9770	2.5 s → 2.8 s	299 MB → 312 MB
transparent-illustration-3.png	sc-balanced-nometa	10809 → 9623 (-11.0%)	0.9761 → 0.9770	2.4 s → 2.8 s	298 MB → 308 MB
transparent-illustration-3.png	sc-visually-lossless	14286 → 16193 (13.3%)	0.9910 → 0.9911	3.9 s → 4.0 s	322 MB → 330 MB
gradient-linear.png	sc-balanced	1343 → 1413 (5.2%)	0.9966 → 0.9965	4.3 s → 4.7 s	470 MB → 491 MB
gradient-linear.png	sc-balanced-nometa	1343 → 1413 (5.2%)	0.9966 → 0.9965	4.2 s → 4.7 s	476 MB → 487 MB
gradient-linear.png	sc-visually-lossless	1257 → 1257 (0.0%)	0.9966 → 0.9966	6.3 s → 6.3 s	492 MB → 509 MB
gradient-radial.png	sc-balanced	2011 → 1936 (-3.7%)	0.9957 → 0.9958	4.9 s → 7.4 s	459 MB → 629 MB
gradient-radial.png	sc-balanced-nometa	2011 → 1936 (-3.7%)	0.9957 → 0.9958	5.0 s → 7.5 s	464 MB → 628 MB
gradient-radial.png	sc-visually-lossless	1825 → 1825 (0.0%)	0.9955 → 0.9955	9.8 s → 9.7 s	628 MB → 631 MB
gradient-sky.png	sc-balanced	788 → 499 (-36.7%)	0.9964 → 0.9965	2.2 s → 4.0 s	405 MB → 519 MB
gradient-sky.png	sc-balanced-nometa	788 → 499 (-36.7%)	0.9964 → 0.9965	2.3 s → 4.0 s	397 MB → 523 MB
gradient-sky.png	sc-visually-lossless	497 → 497 (0.0%)	0.9965 → 0.9965	6.2 s → 6.0 s	543 MB → 549 MB

Listed runs: total time 280.7 s → 223.6 s, total output 14.32 MB → 14.15 MB.