|
| 1 | +import imagemin from 'imagemin' |
| 2 | +import mozjpeg from 'imagemin-mozjpeg' |
| 3 | +import optipng from 'imagemin-optipng' |
| 4 | +import { CompressOptions, ImgInfo } from '../utils/interfaces' |
| 5 | +import { getImageBuffer } from '../utils/getImage' |
| 6 | +var images = require("images"); |
| 7 | + |
| 8 | + |
| 9 | + |
| 10 | +export function lubanCompress({ ctx, info }: CompressOptions): Promise<ImgInfo> { |
| 11 | + /*function getSample(info: ImgInfo) { |
| 12 | + return ['1x1'] |
| 13 | + }*/ |
| 14 | + |
| 15 | + |
| 16 | +function computeInSampleSize(srcWidth :number, srcHeight:number) { |
| 17 | + srcWidth = srcWidth % 2 == 1 ? srcWidth + 1 : srcWidth; |
| 18 | + srcHeight = srcHeight % 2 == 1 ? srcHeight + 1 : srcHeight; |
| 19 | + |
| 20 | + var longSide = Math.max(srcWidth, srcHeight); |
| 21 | + var shortSide = Math.min(srcWidth, srcHeight); |
| 22 | + |
| 23 | + var scale = ( shortSide / longSide); |
| 24 | + if (scale <= 1 && scale > 0.5625) { |
| 25 | + if (longSide < 1664) { |
| 26 | + return 1; |
| 27 | + } else if (longSide < 4990) { |
| 28 | + return 2; |
| 29 | + } else if (longSide > 4990 && longSide < 10240) { |
| 30 | + return 4; |
| 31 | + } else { |
| 32 | + return longSide / 1280 == 0 ? 1 : longSide / 1280; |
| 33 | + } |
| 34 | + } else if (scale <= 0.5625 && scale > 0.5) { |
| 35 | + return longSide / 1280 == 0 ? 1 : longSide / 1280; |
| 36 | + } else { |
| 37 | + return Math.ceil(longSide / (1280.0 / scale)); |
| 38 | + } |
| 39 | + } |
| 40 | + |
| 41 | + function isJpg(buffer: Buffer) { |
| 42 | + return buffer[0] === 255 && |
| 43 | + buffer[1] === 216 && |
| 44 | + buffer[2] === 255 |
| 45 | + } |
| 46 | + |
| 47 | + return getImageBuffer(ctx, info.url) |
| 48 | + .then((buffer)=>{ |
| 49 | + ctx.log.warn('原始文件大小:'+Math.round(buffer.length/1024)+"k") |
| 50 | + if(isJpg(buffer)){ |
| 51 | + ctx.log.warn('本身就是jpg,不用转换:'+info.url) |
| 52 | + return buffer |
| 53 | + } |
| 54 | + ctx.log.warn('luban 格式转换为jpg:'+info.url) |
| 55 | + return images(buffer).encode("jpg")//, {operation:90} |
| 56 | + }) |
| 57 | + /*.then((buffer)=>{ |
| 58 | + var image2 = images(buffer) |
| 59 | + ctx.log.warn('图片尺寸:'+image2.width()+"x"+image2.height()) |
| 60 | + //todo 关键在于获取图片本身的宽高 |
| 61 | + var samplesize = computeInSampleSize(image2.width(),image2.height()) |
| 62 | + if(samplesize <=1){ |
| 63 | + return buffer |
| 64 | + } |
| 65 | + var size2 = Math.round(buffer.length/1024) |
| 66 | + if(size2 <150){ |
| 67 | + //150k以下,不压缩 |
| 68 | + return buffer |
| 69 | + } |
| 70 | + var longsize = image2.width() > image2.height() ? image2.width() :image2.height() |
| 71 | + //长边大于2500,且文件大小小于1024k,就不压缩 |
| 72 | + if(size2 < 1024 && longsize> 2500){ |
| 73 | + return buffer |
| 74 | + } |
| 75 | + var conpressWidth = image2.width()/samplesize |
| 76 | + ctx.log.warn('转换成jpg后文件大小:'+Math.round(buffer.length/1024)+"k") |
| 77 | + ctx.log.warn('准备用luban算法压缩:宽度变化:'+image2.width()+"-->"+conpressWidth) |
| 78 | +
|
| 79 | + return image2.resize(conpressWidth).encode("jpg")//, {operation:90} |
| 80 | + })*/ |
| 81 | + .then((buffer) => { |
| 82 | + ctx.log.warn('文件大小:'+Math.round(buffer.length/1024)+"k") |
| 83 | + |
| 84 | + var image2 = images(buffer) |
| 85 | + ctx.log.warn('图片尺寸:'+image2.width()+"x"+image2.height()) |
| 86 | + //todo 关键在于获取图片本身的宽高 |
| 87 | + var sample = Math.round(computeInSampleSize(image2.width(),image2.height())) |
| 88 | + var filesize = Math.round(buffer.length/1024) |
| 89 | + var longsize = image2.width() > image2.height() ? image2.width() :image2.height() |
| 90 | + var sampleSize = ['1x1']; |
| 91 | + if(filesize > 100 && sample >1){ |
| 92 | + if(longsize >3000 && filesize< 700){ |
| 93 | + |
| 94 | + }else { |
| 95 | + sampleSize = [sample+'x'+sample] |
| 96 | + } |
| 97 | + |
| 98 | + } |
| 99 | + ctx.log.warn('sampleSize:'+sampleSize[0]) |
| 100 | + |
| 101 | + return imagemin.buffer(buffer, { |
| 102 | + plugins: [mozjpeg({ quality: 75,sample:sampleSize})],//, optipng({ optimizationLevel: 5 })//, sample:sampleSize |
| 103 | + }) |
| 104 | + }) |
| 105 | + .then((buffer) => { |
| 106 | + ctx.log.warn('最后mozjpeg compress in success,最终文件大小:'+Math.round(buffer.length/1024)+"k") |
| 107 | + return { |
| 108 | + ...info, |
| 109 | + buffer, |
| 110 | + } |
| 111 | + }) |
| 112 | +} |
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