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裁后尺寸」。",[10,120,121],{},"另一档是四边裁切，对付固定边缘的问题：扫描件的白边与装订孔、截图底部的水印与时间戳。分别填上、右、下、左要裁掉的量，单位选像素求精确；选百分比则按每张图自身尺寸折算，同一设置下小图更容易超限——某张超了会单独标红，不拖累整批。",[14,123,125],{"id":124},"场景二按目标宽高批量缩放","场景二：按目标宽高批量缩放",[10,127,128,129,133],{},"裁剪只保证比例一致，各张图按自身尺寸裁出最大保留区域，像素大小并不统一。要达标，接着进",[108,130,132],{"href":131},"\u002Ftools\u002Fimage\u002Fresize","图片改尺寸","。三种基准对应三类要求：平台限宽度，选「按宽度」填目标像素；一组素材要等高排列，选「按高度」；只想把照片整体缩小一半方便发送，选「按百分比」，可填 10 到 400。",[10,135,136],{},"横图竖图混在一批也无需逐张处理：按宽度缩到 800，4:3 的图高度自动算成 600，16:9 的算成 450，各张按自身比例分别计算，谁也不会被拉变形。",[10,138,139],{},"两句提醒。其一，放大只是把已有像素铺到更大的画布上，补不出新细节（SVG 矢量图除外），需要更清晰的大图请从源头找更高分辨率的原图。其二，浏览器画布有约 1600 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的完整步骤。",[251],"image\u002Fexif",{"path":192,"title":5,"description":178,"category":177,"toolSlugs":253,"updated":198},[196,197],{"path":255,"title":256,"description":257,"category":258,"toolSlugs":259,"updated":231},"\u002Fguides\u002Ftrim-video-lossless-vs-reencode","视频怎么裁出一段：无损截取与重编码怎么选","只想留视频里 30 秒精华？讲清无损截取（秒级出片、不改分辨率帧率）与重编码裁剪的原理差异、各自的画质与兼容性代价，以及双端滑杆精确选段到帧级的操作步骤。","audio-video",[260],"audio-video\u002Fvideo-trim",{"path":262,"title":263,"description":264,"category":219,"toolSlugs":265,"updated":267},"\u002Fguides\u002Fwhat-is-unix-timestamp","Unix 时间戳是什么：秒与毫秒怎么区分、怎么换算","一文讲清 Unix 时间戳：10 位秒级与 13 位毫秒级的自动判断规则、换算差 8 小时的三种常见原因、负数与超限值的边界，附三个真实排查案例与在线换算步骤。",[266],"developer\u002Ftimestamp","2026-09-08",1791906054394]