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usage: im2rec.py [-h] [--list] [--exts EXTS [EXTS ...]] [--chunks CHUNKS] ????????????????[--train-ratio TRAIN_RATIO] [--test-ratio TEST_RATIO] ????????????????[--recursive] [--no-shuffle] [--pass-through] ????????????????[--resize RESIZE] [--center-crop] [--quality QUALITY] ????????????????[--num-thread NUM_THREAD] [--color {-1,0,1}] ????????????????[--encoding {.jpg,.png}] [--pack-label] ????????????????prefix rootCreate an image list or make a record database by reading from an image listpositional arguments: ?prefix ???????????????prefix of input/output lst and rec files. ?root ?????????????????path to folder containing images.optional arguments: ?-h, --help ???????????show this help message and exitOptions for creating image lists: ?--list ???????????????If this is set im2rec will create image list(s) by ???????????????????????traversing root folder and output to <prefix>.lst. ???????????????????????Otherwise im2rec will read <prefix>.lst and create a ???????????????????????database at <prefix>.rec (default: False) ?--exts EXTS [EXTS ...] ???????????????????????list of acceptable image extensions. (default: ???????????????????????[‘.jpeg‘, ‘.jpg‘, ‘.png‘]) ?--chunks CHUNKS ??????number of chunks. (default: 1) ?--train-ratio TRAIN_RATIO ???????????????????????Ratio of images to use for training. (default: 1.0) ?--test-ratio TEST_RATIO ???????????????????????Ratio of images to use for testing. (default: 0) ?--recursive ??????????If true recursively walk through subdirs and assign an ???????????????????????unique label to images in each folder. Otherwise only ???????????????????????include images in the root folder and give them label ???????????????????????0. (default: False) ?--no-shuffle ?????????If this is passed, im2rec will not randomize the image ???????????????????????order in <prefix>.lst (default: True)Options for creating database: ?--pass-through ???????whether to skip transformation and save image as is ???????????????????????(default: False) ?--resize RESIZE ??????resize the shorter edge of image to the newsize, ???????????????????????original images will be packed by default. (default: ???????????????????????0) ?--center-crop ????????specify whether to crop the center image to make it ???????????????????????rectangular. (default: False) ?--quality QUALITY ????JPEG quality for encoding, 1-100; or PNG compression ???????????????????????for encoding, 1-9 (default: 95) ?--num-thread NUM_THREAD ???????????????????????number of thread to use for encoding. order of images ???????????????????????will be different from the input list if >1. the input ???????????????????????list will be modified to match the resulting order. ???????????????????????(default: 1) ?--color {-1,0,1} ?????specify the color mode of the loaded image. 1: Loads a ???????????????????????color image. Any transparency of image will be ???????????????????????neglected. It is the default flag. 0: Loads image in ???????????????????????grayscale mode. -1:Loads image as such including alpha ???????????????????????channel. (default: 1) ?--encoding {.jpg,.png} ???????????????????????specify the encoding of the images. (default: .jpg) ?--pack-label ?????????Whether to also pack multi dimensional label in the ???????????????????????record file (default: False)必须要填写的参数有prefix、和root两个路径参数，
prefix：生成文件文件夹目录
可以指定为.lst的路径，这样生成文件会和.lst同一级别，且会根据.lst中的条目生成二进制文件
root：图片文件目录，默认的话里面是类别文件夹，类别名做label，每个文件夹存储图像
如果指定了.lst，则每个图片路径变为root路径+.lst中每个图片的路径
--pack-label：在指定了.lst后很有用，此时允许label为高维度（主要是label可以设置为数组）
实际上我们之前也介绍过，.lst文件并不是必须的，仅有.rec和.idx就可以满足需要（标签存储在.rec中），它是一个辅助（人工生成.lst指导.rec生成），或者作为一个结果展示（自动生成.rec时选择同时生成.lst）。
『MXNet』im2rec脚本使用（待续）
原文地址：https://www.cnblogs.com/hellcat/p/9373890.html