CSV file and usage

The so-called "CSV" is the abbreviation of comma separated value (comma-separated values). It is usually a plain text file. The following is part of an actual CSV file, which gives you a perceptual knowledge of it. We selected the sjo_rescan CSV file (sjojo is a member of ASW-Asian image scanning ).
Sj_mino1001.jpg, 715282, 4fb55fe8,
Sj_mino1002.jpg, 471289, 93203c 5C ,
Sj_mino1003.jpg, 451929, c4e80467,
Generally, the CSV file starts with a comma (,) and records multiple pieces of data of an image in the unit of action. Each item is separated by a comma ). Generally, the format of the. CSV file used for a set chart is as follows:
File Name, file size (in bytes), CRC Check value, comment (omitted)
Sj_mino1001.jpg, 715282, 4fb55fe8,
|
Comment (Omitted) on CRC value of file name size)
If Microsoft Excel is installed on your machine, the. CSV file is opened by Excel by default. Note that when you double-click. after opening a CSV file or Excel file, even if you do not make any changes, when you close the file, Excel will always prompt whether you want to change it to the correct file format. At this time, remember to select "no ". Because Excel believes that the numbers in the. CSV file are represented by scientific notation, and the numbers in the. CSV file we want are common. If you select "yes", Excel
All numbers in the CSV file are represented by scientific counts (in the form of 2.54932e + 5), and this file cannot be used. If most of your CSV files are used in the Set graph, we recommend that you change. CSV to any text editor by default. The notepad that comes with the system is a good choice.
Okay. Let's go back to the CSV file format. As shown above, from left to right sj_mino1001.jpg is the file name, And 715282 is the file size in bytes. When a file name contains a comma, because of its special role in the CSV file, you need to enclose the file name in quotation marks to avoid ambiguity. For example, "the art, fantasy.jpg", 384211,...,... is followed by an 8-bit hexadecimal number 4fb55fe8, which is the CRC32 check value of the file. The essence of the entire CSV file is here.
Let's take a small example to illustrate its significance: sjojohas a picture sj_mino1001.jpg. If you get this picture from your friends, you will always have such questions, has this image been changed during the propagation process? Is it accidentally damaged? CRC exists to solve this problem. In general, each time a scanner publishes a set of images, a CSV file is released at the same time (this type of CSV is usually called official CSV, that is, the official CSV file ), the CRC value in this CSV is a value generated after file calculation using a special software CRC32 algorithm (commonly used CRC algorithm and crc16). This value can be used as a symbol of the true file. In most cases, if the file size or content is changed during propagation. Then, the CRC value generated after the file is computed using the same CRC32 algorithm is completely different. If the CRC value is the same, there is a reason to think that the file is real and has not been changed. Sometimes, the image file name has been changed. How do you know who is it? At this time, the CRC value takes effect again: after image processing with a dedicated software, you can get the file size and CRC value, and then find out if there is a suitable image based on the size and CRC value in CSV. If yes, the image name will be changed to CSV. For example, you get an image named pic0001.jpg, and you know that this image is in the sjojo_rescan, but you don't know which one it is. . It is not a CSV file but an image file name. The following are comments and descriptions, which can be omitted. Note that there is no comma behind the comment. If you want to omit the comment, you must keep a comma behind the CRC value. Otherwise, the software considers the CRC value as a comment.
I believe that after reading a bunch of things above, you not only have a rough understanding of the CSV file, but also have some vague concepts about its usage. We often collect images through various channels, such as from websites, IRC, or CDs sent by friends. During the whole process of dissemination, images may suffer from a variety of non-human treatments. In particular, images received from websites. In some cases, the name is simply changed. In many cases, due to the limited space of many plmm sites, the image size is usually reduced or the image file size is reduced. It is common for a 1356x588 image to be changed to 678x294, or a 400 or 500 K file to dozens of K. What's worse is that many websites remove the logo of the original scanner and put it on their own website logo. There are also some funny gamers who want to change their faces by moving all kinds of pictures. These are harmless for general pictures and entertainment, but they cannot be tolerated when they are received. How to identify the front of an image is a problem faced by the scanner and the image collector. CSV files are generated to solve such problems. CSV files were first used in a simple database. Because of their simple format and strong openness, they were first marked by their own gallery by the scanner. As mentioned above, a CSV file is a plain text file. Each row represents many attributes of an image. When you collect a set of image sets, you only need to find its CSV file and use special software for verification. Then, you can know the situation of the gallery. For example, the total number of images in this set, the number of images you receive, the source images, and the images that may have been modified or damaged ...... we can. CSV files are regarded as an index. You can not only "search by image", but also check whether the obtained "Ma Zi" lineage is pure.
There are two types of CSV files: one is the CSV file published by the scanner itself, which is generally called official CSV. That is, the officially published CSV file is usually authoritative. In particular, there are also some privately published special diagrams in addition to publicly published ones in Asia, or those specially sent to friends. In addition, they do not want to or do not want to make CSV files, so the CSV files of their Gallery are often made by some senior predecessors in the graph community. In this case, there are usually several versions of CSV files in an gallery, and there is a lot of difference between each version. At this time, CSV is not only the basis for verifying the truth, but also a hope for the collectors: even if there are more missing ones, that is, there will be fewer people using this version of CSV, there must be one person who is the author of the CSV file! Liqing, a senior in the graph industry, has a famous saying: "If you have CSV, you must have a graph !" Naturally, there are some authoritative CSV players. For example, in the early edzone, the active Osun, Shum, VSAM, Te, Paul... And wqc of COC tuumeng
Well, after talking about that, you may ask how to use CSV files that are so easy to use? I don't need to manually detect it, do I? Well, do you still remember the word "software" again mentioned above? Dedicated software can help us do this. Common Software include! Checker and the hunter.