1、 主要内容:主要内容:1图像压缩基础;图像压缩基础;2 无损压缩的常用技术;无损压缩的常用技术;3有损压缩的常用技术;有损压缩的常用技术;4MATLAB图像压缩;图像压缩;2022年10月4日16时36分 主要内容:主要内容:1图像压缩基础;图像压缩基础;2 无损压缩的常用技术;无损压缩的常用技术;3有损压缩的常用技术;有损压缩的常用技术;4MATLAB图像压缩;图像压缩;2022年10月4日16时36分图像数据图像数据分辨率分辨率比特比特/像素像素大小大小(B)传输带宽传输带宽(b)传输时间传输时间(28.8Kbps Modem)灰度图像灰度图像5125128256K2M1min 11sec
2、彩色图像彩色图像51251224768K6M3min 34sec医学图像医学图像10241024121.5M12M7min6sec动态视频动态视频640 x 480 1分钟分钟(24 帧帧/秒秒)241.24G169M4days 4hrsRDCR1121nnCRRGBRGBRGBRGBRGBRGBRGBRGBRGBRGBRGBRGBRGBRGBRGBRGB16RGB224颜色颜色28颜色颜色10()()LavgkrkkLl rp rrkPr(rk)等长编码等长编码l1(rk)变长编码变长编码l2(rk)00.1900031121/70.2500130122/70.2101031023/70.1
3、6011300134/70.081003000145/70.0610130000156/70.031103000001610.0211130000006Pr(rk)l2(rk),.,2,1()(log)(2riaPaIiiriiiaPaPH12)(log)(),.,2,1()(log)(2riaPaIiiriiiaPaPH12)(log)(riiiavgalaPL1)()(1)(1XHLRavg原始图象的信息熵原始图象平均码长%10011%100RLHavgrkPr(rk)等长编码等长编码l1(rk)变长编码变长编码l2(rk)00.1900031121/70.2500130122/70.21
4、01031023/70.16011300134/70.081003000145/70.0610130000156/70.031103000001610.0211130000006Lavg=3Lavg=2.705001000150020002500050100150200250原图原图JPEG 100JPEG 100:1 1无损压缩无损压缩有损压缩有损压缩压缩数据还原后,与原始数据一致,无损失。压缩数据还原后,与原始数据一致,无损失。压缩后再还原的数据有损失。压缩后再还原的数据有损失。可逆编码可逆编码不可逆编码不可逆编码压缩比:压缩比:2:15:1压缩比:压缩比:100:1),(),(),(yx
5、fyxfyxe 1010),(),(MxNyyxfyxf21 10102 rms),(),(1 MxNyyxfyxfMNe信源 编码器信道 编码器信道信源 解码器信道 解码器编码器解码器输入图输出图 主要内容:主要内容:1图像压缩基础;图像压缩基础;2 无损压缩的常用技术;无损压缩的常用技术;3有损压缩的常用技术;有损压缩的常用技术;4MATLAB图像压缩;图像压缩;2022年10月4日16时36分无损压缩无损压缩霍夫曼编码霍夫曼编码行程编码行程编码算术编码算术编码LZW编码编码无损预测编码无损预测编码3010402020402002020303020402040301040202040200
6、20203030204020401/161/162/1630104020204020020203030204020401/161/162/163/165/1630104020204020020203030204020401/161/162/163/165/164/169/1630104020204020020203030204020401/161/162/163/165/164/169/167/16130104020204020020203030204020401/161/162/163/165/164/169/167/1610100301400200111030104020204020020
7、203030204020401/161/162/163/165/164/169/167/1610100301400200111030104020204020020203030204020401/161/162/163/165/164/169/167/16101003014002001110(3,)(12,)(4,)(9,)(1,)(a)(b)130130130129134133129130130130130129134133130130130130130129132132130130129130130129130130129129127128127129131 129131 130127128
8、127128127128132132125126129129127129133132127125128128126130131131f130,130,130,129,134,133,129,130;130,130,130,129,134,133,130,130;130,130,130,129,132,132,130,130;129,130,130,129,130,130,129,129;127,128,127,129,131,129,131,130;127,128,127,128,127,128,132,132;125,126,129,129,127,129,133,132;127,125,1
9、28,128,126,130,131,131(3,130),(),(1,129),(),(1,134),(),(1,133),(),(1,129),(),(4,130),),(1,129),(),(1,134),(),(1,133),(),(5,130),(),(1,129),(),(2,132),),(2,130),(),(1,129),(),(2,130),(),(1,129),(),(2,130),(),(2,129),),(1,127),(),(1,128),(),(1,127),(),(1,129),(),(1,131),(),(1,129),),(1,131),(),(1,130)
10、,(),(1,127),(),(1,128),(),(1,127),(),(1,128),),(1,127),(),(1,128),(),(2,132),(),(1,125),(),(1,126),(),(2,129),),(1,127),(),(1,129),(),(1,133),(),(1,132),(),(1,127),(),(1,125),),(2,128),(),(1,126),(),(1,130),(),(2,131)130,130,130,129,127,127,125,127;130,130,130,130,128,128,126,125;130,130,130,130,127
11、,127,129,128;129,129,129,129,129,128,129,128;134,134,132,130,131,127,127,126;133,133,132,130,129,128,129,130;129,130,130,129,131,132,133,131;130,130,130,129,130,132,132,131(3,130),(),(1,129),(),(2,127),(),(1,125),(),(1,127),(),(4,130),),(2,128),(),(1,126),(),(1,125),(),(4,130),(),(2,127),(),(1,129),
12、),(1,128),(),(5,129),(),(1,128),(),(1,129),(),(1,128),(),(2,134),),(1,132),(),(1,130),(),(1,131),(),(2,127),(),(1,126),(),(2,133),),(1,132),(),(1,130),(),(1,129),(),(1,128),(),(1,129),(),(1,130),),(1,129),(),(2,130),(),(1,129),(),(1,131),(),(1,132),(),(1,133),),(1,131),(),(3,130),(),(1,129),(),(1,130),(),(2,132),(),(1,131)重点重点基本概念:图像压缩、相对数据冗余、压缩率、像素基本概念:图像压缩、相对数据冗余、压缩率、像素间冗余、心理视觉冗余、编码冗余、变长编码、信息间冗余、心理视觉冗余、编码冗余、变长编码、信息熵、编码效率、无损压缩、有损压缩熵、编码效率、无损压缩、有损压缩霍夫曼编码算法原理与步骤霍夫曼编码算法原理与步骤 了解了解行程编码、压缩图像质量评价的主客观标准行程编码、压缩图像质量评价的主客观标准本章小结:2022年10月4日16时36分