High Performance Images

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  @COLINBENDELL HIGH PERF. IMAGES #✈"#

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What elephant?

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VS.

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94% ARTICLES WITH IMAGES GET M O R E TOTAL VIEWS

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business"

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The   Business PROFIT! ... MAKE MONEY  ... LOWER COSTS

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Linen Chest optimized images: 30% increase in tablet; 10% increase in conversion

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TODO  ☑︎make images "fast"

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30% faster without images (3G) Guy Podjarni

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business"

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User FAST EXPERIENCE ... DESPITE HARDWARE  ... EVEN ON CELLULAR

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NOV-2010 NOV-2016 1,624KB 416KB Images Javascript Video CSS WebFonts HTML Other 2,509KB 702KB

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H T T PA R C H I V E . O R G : I M A G E S > 6 0 % 0KB 400KB 800KB 1,200KB 1,600KB 0 25 50 75 100 125 15-NOV-10 15-MAR-11 15-JUL-11 15-NOV-11 15-MAR-12 15-JUL-12 15-NOV-12 15-MAR-13 15-JUL-13 15-NOV-13 1-APR-14 1-AUG-14 1-DEC-14 1-APR-15 1-AUG-15 1-DEC-15 1-APR-16 1-AUG-16 1,577KB 416KB 48 56

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R W D : O N E U R L , A D A P T T O S C R E E N S I Z E

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DESKTOP MOBILE 1,465KB 1,624KB Images Javascript Video CSS WebFonts HTML Other 2,175KB 2,509KB

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AUTOMOTIVE BUSINESS CMG EDUCATION FIN. TECH NOT 4 P GAMING HIGH TECH TRAVEL MANUFACTURIN MEDIA HEALTH PUBLIC SECTOR RETAIL SAAS 38KB 27KB 46KB 29KB 22KB 36KB 42KB 51KB 45KB 56KB 42KB 71KB 33KB 47KB 72KB AVERAGE JPG SIZE

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360X 760X 1260X 370 KB 293 KB 168 KB 635 KB 623 KB 604 KB Responsive Images can save 72% of bytes! Tim Kadlec

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TODO  ☑︎make images "fast"  ☑︎use responsive images

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business"

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Marketing AWESOME BRAND ... EXPERIENCE ... EMOTION

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94% ARTICLES WITH IMAGES GET M O R E TOTAL VIEWS

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http://www2.palomar.edu/users/rmorrissette/Lectures/Physio/210Vision_ﬁles/slide0212_image003.jpg

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S P E C T R A L S E N S I T I V I T Y   ( P R O B A B I L I T Y V. WAV E L E N G T H )

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P3 sRGB

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https://upload.wikimedia.org/wikipedia/commons/6/63/Human_eye_-_blue.JPG

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TODO  ☑︎make images "fast"  ☑︎use responsive images  ☑︎high quality

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business"

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Operations RELIABLE OPERATIONS ... CONSISTENCY  ... WITHOUT INTERRUPTION

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0 18.75 37.5 56.25 75 4KB SHALLOW DIRECTORY STRUCTURE 4KB DEEP DIRECTORY SHALLOW 4MB SHALLOW DIRECTORY STRUCTURE 4MB DEEP DIRECTORY STRUCTURE 72MB/s 80MB/s 2MB/s 4MB/s

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TODO  ☑︎make images "fast"  ☑︎use responsive images  ☑︎high quality  ☑︎Disaster recovery

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business"

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Security PROTECT THE BUSINESS ... REDUCE RISK   ... STOP BAD GUYS

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PREVENT TRANSPARENT PROXIES CAN HIJACK YOUR IMAGES  ... FOR GOOD OR ILL

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CRITICAL VULNERABILITIES AND EXPOSURE (CVE) 0 4.5 9 13.5 18 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 ImageMagick libjpegturbo libjpeg libpng giﬂib openjpeg

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ImageMagick Is On Fire — CVE-2016–3714

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TODO  ☑︎make images "fast"  ☑︎use responsive images  ☑︎high quality (p3, retina)  ☑︎Disaster Recovery   ☑︎secure

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business"

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Dev GET STUFF DONE ... BALANCING OPINIONS  ... GSD FASTER

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0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 M A G I C N U M B E R : 2 S E C O N D S ( E V E N O N C E L L U L A R )

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☑︎make images "fast"  ☑︎use responsive images  ☑︎high quality (p3, retina)  ☑︎Disaster Recovery   ☑︎secure  ☑︎get stuff done by monday

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http://davemakes.tumblr.com/post/36136418100/50000-red-lego-bricks

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So... where do I start? User Sec. Mktg Dev Ops Business

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STEP 1:  USE THE RIGHT FORMAT

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VECTOR IMAGES  MADE OF MATH

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SVG: 256K PNG: 24K PNG (crush): 20K PNG8: 7K SVG (svgo): 91K

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O P T I M I Z E S V G • Scour  www.coderead.com/scour/ • SVGO  github.com/svg/svgo • SVGOMG (gui)  jakearchibald.github.io/svgomg

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B O N U S : S V G C S S S T Y L E W I T H W I D E G A M U T .main { background: rgb(241, 0, 0); } @media (color-gamut: p3) { .main { background: rgb(244, 0, 0); } } /* future */ @media (color-gamut: p3) { .main { background: color(p3 1.0 0 0); } }

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RASTER IMAGES:  MADE OF PIXELS • GIF • PNG • WebP • JPEG • JPEG 2000 • JPEG XR

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LOSSLESS GIF, PNG, WEBP, JP2 RAW, TIFF, BMP, BPG, FLIF

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LOSSY GIF, JPG, WEBP, JP2

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G I F • 1987 (Previously Patented) • 256 Colors • “Simple” Transparency • Supported Everywhere • Universal support for Animation • image/gif

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P N G – P O R TA B L E N E T W O R K G R A P H I C S • 1996 (no patent) • PNG8 and PNG24 • Supports Alpha Transparency • Good browser support • image/png • image/apng

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L O S S L E S S P N G O P T I M I Z AT I O N - Convert from PNG 24 -> 8 - Trade “Alpha” transparency with simple (100%) transparency - PNG Optimization Tools: TinyPNG, PNGCrush, OptiPNG

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J P E G – J O I N T P H O T O G R A P H I C E X P E R T S G R O U P - 21 years old (1992) - Supports RGB Colors (8 bit per channel) - First major lossy format. - No transparency support. - Extensive chroma subsampling support. - Supports progressive loading. - Compressed with: - Discrete Cosine Transformation - Quantization - Huffman encoding

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J P E G C O M P R E S S I O N 1. Divide image into 8x8 pixel blocks

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J P E G C O M P R E S S I O N 1. Divide image into 8x8 pixel blocks 2. Split Luminance & Chrominance Y Cb Cr

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J P E G C O M P R E S S I O N - S I M P L I F I E D 1. Divide image into 8x8 pixel blocks 2. Split Luminance & Chrominance 3. Write pixels as ~delta from average • and round (DCT + Quantization) Y Cb Cr

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Define Quantization Table 0 precision 0 160 110 100 160 240 255 255 255 120 120 140 190 255 255 255 255 140 130 160 240 255 255 255 255 140 170 220 255 255 255 255 255 180 220 255 255 255 255 255 255 240 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 Define Quantization Table 1 precision 0 170 180 240 255 255 255 255 255 180 210 255 255 255 255 255 255 240 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 255 Define Quantization Table 0 precision 0 10 7 6 10 14 24 31 37 7 7 8 11 16 35 36 33 8 8 10 14 24 34 41 34 8 10 13 17 31 52 48 37 11 13 22 34 41 65 62 46 14 21 33 38 49 62 68 55 29 38 47 52 62 73 72 61 43 55 57 59 67 60 62 59 Define Quantization Table 1 precision 0 10 11 14 28 59 59 59 59 11 13 16 40 59 59 59 59 14 16 34 59 59 59 59 59 28 40 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 59 QUALITY 70 QUALITY 5

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J P E G C O M P R E S S I O N 1. Divide image into 8x8 pixel blocks 2. Split Luminance & Chrominance 3. Write pixels as ~delta from average and round (DCT + Quantization) 4. Write as line, compress (Huffman) = -9,-1,0(x62)

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J P E G C O M P R E S S I O N 1. Divide image into 8x8 pixel blocks 2. Split Luminance & Chrominance 3. Write pixels as delta from average and round (DCT + Quantization) 4. Write as line, compress (Huffman) Q=10 Q=50 Original

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L O S S Y C O M P R E S S I O N – N O T F O R E V E RY O N E

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J P E G B A S E L I N E V S . P R O G R E S S I V E http://www.bookofspeed.com/chapter5.html 1 2 0 0 1 0 0 0 3 -1 0 0 1 2 0 0 1 0 0 0 3 -1 0 0 1 1 3 2 0 -1 0 0 0 0 0 0 1 1 3 2 0 -1 EOB

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J P E G 2 0 0 0 • Supports full transparency • Supports chroma subsampling • Supports progressive loading • Compressed with: • Discrete Wavelet Transformation • Quantization • Arithmetic encoding

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W E B P ( 2 0 1 1 ) • Supports full transparency. • Supports animation on some recent browsers. • Supports only 4:2:0 chroma subsampling. • Does NOT support progressive loading. • Compresses with: • Discrete Cosine Transformation • Block prediction • Quantization • Arithmetic encoding

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J P E G X R • Supports full transparency. • Supports chroma subsampling. • Supports progressive loading. • Compressed with: • Hierarchical Lapped Biorthogonal Transform • Block prediction • Quantization • Huffman encoding

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GIF 25% WebP 1% PNG 27% JPEG 45%

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F O R M AT F E AT U R E S U P P O R T

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O P T I M I Z E R A S T E R • Use JPeg2000 for iOS/Safari • Use WebP for Android/Chrome • Progressive Jpeg • Image Optim (Jpeg/PNG/Gif): https://imageoptim.com • Tiny PNG: https://tinypng.com/

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STEP 2:  OPTIMIZE FOR MOBILE

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0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 NOT YOU YOU

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0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 M A G I C N U M B E R : 2 S E C O N D S ( E V E N O N C E L L U L A R )

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Nexus 7 Android 1 Moto e Moto g Nexus 5 334ms 1002ms 1180ms 222ms 494ms Desktop 103ms 2.0s 1.0s 3.0s N O T A L L M O B I L E D E V I C E S M A D E E Q U A L

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Copy to GPU Display Network  Request Decode

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CELLULAR: OUT OF YOUR CONTROL

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0 1250 2500 3750 5000 CARRIER 1 CARRIER 3 CARRIER 4 CARRIER 5 CARRIER 6 HTTP TLS

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PREVENT TRANSPARENT PROXIES FROM DISTORTING YOUR IMAGES CACHE-CONTROL: NO-TRANSFORM

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1280 x 520

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R: 78 G: 101 B: 23 A: 1 R: 31 G: 33 B: 26 A: 1

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1 2 8 0 X 5 2 0 X 4 B Y T E S = 2 . 6 M B !

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600x600 200x200 1000x1000 x4 x4 x4 1.4MB 156KB 3.9MB

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550x550 150x150 950x950 x4 x4 x4 1.2MB (-200KB) 88KB (-68KB) 3.5MB (-400KB)

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Nexus 7 Android 1 Moto e Moto g Nexus 5 334ms 1002ms 1180ms 222ms 494ms Desktop 103ms 2.0s 1.0s 3.0s N O T A L L M O B I L E D E V I C E S M A D E E Q U A L

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More breakpoints the larger the image dimensions Tim Kadlec 100 1000p

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COMPRESSION V. QUALITY

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Quality is JUST an Index! It is not compression Nick Doyle

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Q5: 5KB Q10: 9KB Q15: 13KB Q50: 31KB Q75: 46KB Q90: 99KB

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Changing File Size with Quality is snakeoil! Kornel Lesiński

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SSIM(x, y) = (2µx µy +c 1 )(2σxy +c 2 ) (µx 2 +µy 2 +c 1 )(σx 2 +σy 2 +c 2 ) Zhou Wang, Alan C. Bovik, Hamid R. Sheikh, and Eero P. Simoncelli

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Q10 DSSIM: 0.0566 Q50 DSSIM: 0.0251 Q80 DSSIM: 0.0179

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Q85 61KB Q78 48KB

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Q85 30KB Q78 23KB

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QUALITY V. DSSIM 0.0000 0.0400 0.0800 0.1200 0.1600 0.2000 0.2400 0.2800 0.3200 0.3600 0.4000 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 JPEG (libjpegturbo) JPEG (mozjpeg) JPEG 2000 (OpenJPEG) JPEG 2000 (Kakadu) JPEG XR WebP

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QUALITY (90-40) V. DSSIM 0.0000 0.0109 0.0218 0.0327 0.0436 0.0545 0.0655 0.0764 0.0873 0.0982 0.1091 0.1200 90 85 80 75 70 65 60 55 50 45 40 JPEG (libjpegturbo) JPEG (mozjpeg) JPEG 2000 (OpenJPEG) JPEG 2000 (Kakadu) JPEG XR WebP

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O P T I M I Z E F O R S S I M • RGBA Structural Similarity  kornel.ski/dssim • butteraulgi  github.com/google/butteraugli

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CHROMA-SUB SAMPLING TRICKING THE EYE

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R G B A = 2 . 6 M B ! 4 : 4 : 4 = 1 . 9 M B 4 : 2 : 2 = 1 . 3 M B 4 : 2 : 0 = 0 . 9 M B

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JPG includes EXIF, I can strip this out - right?

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M E TA D ATA https://blog.dexecure.com/impact-of-metadata-on-image-performance/

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ICC PROFILES

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ONLY WIDE-GAMUT DISPLAYS CAN SEE THIS

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O P T I M I Z E M E TA D ATA • STRIP Most Metadata • Keep Copyright • Keep ICC (convert to RGB first!)

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☑︎WebP & JP2000  ☑︎Resize  ☑︎Chroma Subsampling   ☑︎DSSIM  ☑︎TLS

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STEP 3:  SIMPLIFY

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new Imager({ availableWidths: [200, 260, 320, 600], availablePixelRatios: [1, 1.3, 2] });

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1. Use srcset to list image dimensions 2. Use 'w' notation for pixel 'widths' 3. don't use 'x' for DPR 4. Use sizes to help the browser pick the right size  (defaults to using the device viewport) 5. Use small src for default

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Copy to GPU Display Pre- Loader Network  Request Decode

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150px 2,000px 1000px

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150px 2,000px 300px 600px 800px 1000px

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0KB 23KB 45KB 68KB 90KB 150X 300X 600X 800X 123.0KB 58.3KB 21.2KB 7.6KB 74.7KB 33.9KB 12.0KB 4.1KB 46.3KB 20.3KB 7.3KB 2.5KB 25th Median 75th

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0KB 175KB 350KB 525KB 700KB 1000X 1200X 2000X 4000X 953KB 388KB 251KB 186KB 432KB 320KB 144KB 113KB 217KB 120KB 83KB 70KB 25th Median 75th

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1. Use SrcSet not for Responsive Images 2. Use a polyfill   scottjehl.github.io/picturefill/ 3. Use lazy sizes polyfill  github.com/aFarkas/lazysizes 4. Hide hidden Images 5. Hide Blow the Fold R E S P O N S I V E I M A G E S

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CLIENT HINTS: BACK TO BASICS

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GET /You-Won't-Believe-What-Happened-Next.html 200 OK (PS: send Hints) GET /giant-galoshes.jpg (PS: I'm a S7 note; on cellular) (PPS: I'm on ﬁre) 200 OK (PS: I shrunk the image) CLIENT HINTS: BACK TO BASICS

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response.setHeader('Accept-CH', 'Viewport-Width, Width, DPR'); OR

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Viewport-Width: 375

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Width: 150

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DPR: 2

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Width: 150 300

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GET /is_awesome.jpg Accept: image/webp, */* DPR: 2 Width: 300 Viewport-Width: 375

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GET /is_awesome.jpg Accept: image/webp, */* DPR: 2 Width: 300 Viewport-Width: 375 User-Agent: Mozilla/5.0 (iPhone; CPU OS 10_0 ...

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HTTP/1.1 200 OK Content-Type: image/jp2 Content-DPR: 2 Vary: Accept, DPR, Width response.setHeader('Content-Type', 'image/jp2'); response.setHeader('Content-DPR', '2'); response.setHeader('Vary', 'Accept, DPR, Width');

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By Jon Sullivan - http://pdphoto.org/PictureDetail.php?mat=pdef&pg=8232, Public Domain, https://commons.wikimedia.org/w/index.php?curid=95997

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By Jon Sullivan - http://pdphoto.org/PictureDetail.php?mat=pdef&pg=8232, Public Domain, https://commons.wikimedia.org/w/index.php?curid=95997

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By Jon Sullivan - http://pdphoto.org/PictureDetail.php?mat=pdef&pg=8232, Public Domain, https://commons.wikimedia.org/w/index.php?curid=95997 Content-DPR: 0.5

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Save-Data: on

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LEGACY SUPPORT

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// place JavaScript at top of the page to prevent race condition // reset the CH (ClientHint) cookie values with actual display width if (document.cookie.match(/(^|;)\s*CH-Verify=/)) { var width = (screen.availWidth || screen.width); var dpr = (window.devicePixelRatio || 1); document.cookie = 'CH=Viewport-Width=' + width + ',DPR=' + dpr + ';expires=Fri, 31 Dec 9999 23:59:59 GMT;path=/'; document.cookie ='CH-Set=; expires=Thu, 01 Jan 1970 00:00:01 GMT;' }

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if (Save-Data = 'on') then DPR = 1 let image_width = Width || Viewport-Width * DPR || Cookie.Viewport-Width * Cookie.DPR || DefaultWidth

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APP SUPPORT

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/// /// Add Client Hints to the HTTP request for images to populate the UIImageView. /// This will interrogate the screen and UIView to determine the hint values. /// func clientHints(imageUrl: String, targetImage:UIImageView) { let nsURL = NSURL(string: imageUrl) let config = NSURLSessionConfiguration.defaultSessionConfiguration() let screen = UIScreen.mainScreen() /// use the main screen for size and scale; UIView frame for let viewportWidthPx = screen.bounds.size.width let dpr = screen.scale let width = targetImage.frame.size.width /// convert to CSS Pixels let viewportWidth = Int(Double(viewportWidthPx) / Double(dpr)) config.HTTPAdditionalHeaders = ["Viewport-Width" : viewportWidth] config.HTTPAdditionalHeaders = ["DPR" : dpr] config.HTTPAdditionalHeaders = ["Width" : width] config.HTTPAdditionalHeaders = ["Save-Data" : "on"] /// usual NSURLSession to UIImage work from here /// Accept-CH likely won't make sense since your app /// controls the UIView dimensions let session = NSURLSession(configuration: config) let task = session.dataTaskWithURL(nsURL) { (data, response, error) in if !error { /// make sure that the image is drawn on screen var image:UIImage = UIImage(data: data) dispatch_async(dispatch_get_main_queue(), { targetImage.image = image }) } } task.resume() }

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F O R M AT F E AT U R E S U P P O R T

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1. Opt-In to Client Hints (for 3rd party content!) 2. Add sizes to

3. Use Accepts header and Device Detection P R I O R I T Y L I S T

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☑︎Responsive Breakpoints  ☑︎Client Hints  ☑︎Lazy Loading

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User Batman Security Marketing Dev Ops W H O C A R E S A B O U T I M A G E S ? "Business" ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓

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1. Optimize for Mobile a) Use SVG, WebP & Jpeg 2000 b) Resize Images & Use Chroma-Subsampling c) DSSIM not Quality Index d) Use TLS 2. Use Client Hints (& Lazy Loading) with   Breakpoints: 150, 300, 600, 800 1000, 1200, 2000, 4000 3. Build a Disaster-Recovery-Plan 4. Monitor user performance S U M M A RY

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Thank-You! @colinbendell

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XYZ RGB sRGB CMYK YCbCr YCgCo COLOUR

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http://www.dpbestﬂow.org/color/color-space-and-color-proﬁles s

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RGB

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http://www.dpbestﬂow.org/color/color-space-and-color-proﬁles

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CMYK

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YCbCr

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YCgCo v. YCbCr R = Y + 1.402 (Cr - 128) G = Y - 0.34414 (Cb - 128) - 0.71414 (Cr - 128) B = Y + 1.772 (Cb - 128) Y 1/4 1/2 1/4 R Cg = -1/4 1/2 -1/4 G Co 1/2 0 -1/2 B [ [ [ [ [ [

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XYZ RGB sRGB CMYK YCbCr YCgCo COLOUR

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TCP UNDER THE COVERS

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SMALL IMAGES

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Pixels Bytes Browser Cache 128x128 1.39KB 3.6 KB 128x128 3.34KB 5.6 KB 128x128 6.55 KB 9.6 KB 128x128 5.42 KB 9.6 KB

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BONUS: VIDEO

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ffmpeg -i video.gif -c:v libx264 -an -movflags faststart   -pix_fmt yuv420p -s 544x292 video.mp4 GIF = 4,3 MB WebP = 3,3 MB MP4 = 143 kB