# PNG sequence. Storage. Windows. Which archiver and archive format to apply?



## Konskoo (Mar 24, 2020)

Hi! I thought. What is the best way to store video? I decided. I will store it as a PNG sequence (PNG Image Sequence, frame sequence). I work in Windows 10 Home 64-bit.

The next moment arose. I save the PNG sequence in a folder. I want to backup. I want to do a backup over the network to another computer. It also has Windows 10 Home 64-bit. Copying over the network a lot of small PNG files is irrational. I want to archive PNG sequence. Then I will copy one file over the network. It is enough for me to archive without compression.

Questions. Which archiver to apply? What archive format to apply? Maybe there are nuances, settings? What is good to know. Any special options when creating the archive? Maybe it’s more rational to make an archive while working with the archiver from the command line? Maybe it is important to specify any keys when working with the archiver from the command line?

I want it to be reliable, safe. So that I can safely unpack it at the right time. Please help me with advice


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## Stancestans (Apr 26, 2009)

Welcome to TSF.

https://www.7-zip.org/ will sort you out. Explore the site, links to more information will answer your questions.


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## Konskoo (Mar 24, 2020)

Stancestans said:


> https://www.7-zip.org/ will sort you out. Explore the site, links to more information will answer your questions.


Thank you, Stancestans.

I have PNG sequence - 2000 small PNG files. 19-22 kB each file. I want to store them in archive. I work in Windows 10 Home 64-bit. I want to use 7-Zip archiver. It is enough for me to archive without compression. 7-Zip archiver allows to use formats 7z, bzip2, gzip, tar, wim, xz, zip. What format to use?


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## Stancestans (Apr 26, 2009)

Any format will do since you're not compressing.


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## Konskoo (Mar 24, 2020)

Stancestans said:


> Any format will do since you're not compressing.


Thank you, Stancestans.

I will use 7-Zip. I will use zip format. I will make zip without compression. I will use command line. From 7-Zip help I know there is t (Test integrity of archive) command. Tests archive files. Example:

```
7z t archive.zip *.doc
```
Tests *.doc files in archive archive.zip. What for this command is? In which situation you use it?


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## Stancestans (Apr 26, 2009)

Testing the integrity of the archive means checking it for errors or corruption that would affect extraction of its contents. In other words, you test the archive to check if it is intact or damaged.


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## Konskoo (Mar 24, 2020)

Stancestans said:


> Testing the integrity of the archive means checking it for errors or corruption that would affect extraction of its contents. In other words, you test the archive to check if it is intact or damaged.


Thank you, Stancestans.

Do I understand right way the following?

-------------------------------------------------------

In this case


```
7z t archive.zip
```
I check integrity of zip file? I check just one file - zip file.

-------------------------------------------------------

In this case


```
7z t archive.zip *
```
I check integrity of every file inside zip file? But I don't check integrity of zip file itself?


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## Stancestans (Apr 26, 2009)

Konskoo said:


> Thank you, Stancestans.
> 
> Do I understand right way the following?
> 
> ...


Both

```
7z t archive.zip
```
and 

```
7z t archive.zip *
```
do exactly the same thing. 
If you don't supply a filename or wildcard, then the program assumes you've supplied the wildcard *, so ALL files in the archive are tested. This is explained in the manual/help as follows:



> The default wildcard "*" will be used if there is no filename/wildcard in the command line


The t command is used to test the files inside an archive. This does not mean the archive itself is not being tested. In fact, the archive is only good if all the files it contains are retrievable, so by testing the files inside the archive, you're literally also testing the archive itself. You can't say you have a good archive if the files it contains are not retrievable. Likewise, you cant say you have a good archive if it contains retrievable. but corrupt files.


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## Konskoo (Mar 24, 2020)

Stancestans said:


> Both
> 
> ```
> 7z t archive.zip
> ...


Thank you, Stancestans


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## Konskoo (Mar 24, 2020)

From 7-Zip help I know there is h (Hash) command. Calculate hash values for files.

Syntax

h [-scrc{Method}] [files]

Supported methods: CRC32, CRC64, SHA1, SHA256, BLAKE2sp. Default method is CRC32.

In which situation you use h (Hash) command?


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## Stancestans (Apr 26, 2009)

https://www.google.com/search?q=when+to+use+file+hash


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## Konskoo (Mar 24, 2020)

Stancestans said:


> https://www.google.com/search?q=when+to+use+file+hash


Thank you, Stancestans


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