Image Resolution Converter

免费图像分辨率转换器 — 即时换算 DPI、PPI、每厘米点数等

使用 OmniConverter 免费在线图像分辨率转换器在 DPI、PPI、每厘米点数等单位之间即时换算。专为中国设计行业打造,涵盖印刷出版所需的 300 DPI 标准、医学影像 DICOM 格式的分辨率要求,以及电商主图、详情页的像素规范。平面设计师、排版师和影像诊断医师都能快速找到精确数值。

使用方法

通过三个简单步骤进行转换。

1

输入图像分辨率值

2

选择源分辨率单位与目标单位

3

查看转换后的分辨率

热门换算

常用基准

参考

1 DPIDPI

1 DPI

参考

1 DPIPPI

1 PPI

参考

1 DPIdot/m

39.3700787402 dot/m

参考

1 DPIdot/cm

0.3937007874 dot/cm

参考

1 DPIdot/mm

0.0393700787 dot/mm

参考

1 DPIpx/cm

0.3937007874 px/cm

参考

1 DPIpx/mm

0.0393700787 px/mm

实际应用场景

在中国印刷行业,标准印刷分辨率为300 DPI。一张A4(210×297mm)宣传册需要2,480×3,508像素。专业摄影作品交付给出版社时要求300 PPI、CMYK色彩模式。网页使用72 PPI即可,但苹果Retina屏需要@2x(144 PPI)甚至@3x(216 PPI)的资源。扫描仪:文档归档使用300 DPI、照片600 DPI、胶片/幻灯片2,400-4,800 DPI。在医学影像领域,DICOM标准常见分辨率:CT为512×512像素,MRI为1,024×1,024像素。在UI设计中,设计师为不同屏幕密度导出切图——Android的mdpi(1×)、hdpi(1.5×)、xhdpi(2×)、xxhdpi(3×)、xxxhdpi(4×)。在大幅面喷绘(海报、灯箱)中,近距离观看需要150-200 DPI,远距离观看(如高速路广告牌)15-30 DPI即可。国家地理信息公共服务平台的卫星影像分辨率达到亚米级。打印机的DPI(如爱普生墨点式达5,760×1,440 DPI)与图像的PPI不同,需要匹配。高德和百度地图的瓦片图像分辨率为72 PPI。婚纱摄影精修图的输出尺寸约6,000×4,000像素(2,400万像素),可用于巨幅照片。

常见问题

常见换算问题的快速解答

300DPI是什么意思?+

300 DPI(每英寸点数)是高品质印刷标准。中国印刷业采用此标准。A4印刷需2,480×3,508像素。

医学影像DICOM是什么?+

DICOM是医学数字成像和通信标准。中国医院放射科使用DICOM格式,分辨率72-300 DPI。

DPI和PPI的区别?+

DPI是印刷点数,PPI是屏幕像素数。数值上等效,但分别用于印刷和显示。

如何将DPI换算成点/cm?+

DPI除以2.54得到点/cm。

网页图片需要多少分辨率?+

网页标准72 PPI。高清屏(Retina)需144 PPI。

如何将px/cm换算成DPI?+

px/cm乘以2.54得到DPI。

打印照片需要多少像素?+

6寸照片(4×6英寸)在300DPI下需1,200×1,800像素。

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