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# N545

SSTV Decode

## <mark style="color:red;">Downloading Challenge Files</mark>

here is the executable file to download

{% file src="/files/0sKXhNE3JViaPzGLjCJj" %}

in this challenge we are given an aufio file and from the challenge name which is NASA and the audio file which is moon this audio file could be an SSTV Encoding so let's decode it using a tool i have found on github

<mark style="color:purple;">**Slow-scan television (SSTV)**</mark> is a method for picture transmission used by amateur radio operators to transmit and receive images. SSTV uses analog frequency modulation, in which every different value of brightness in the image gets a different audio frequency

{% embed url="<https://github.com/colaclanth/sstv>" %}

to install you have to clone the github repository into your machine using this command

```
sudo git clone https://github.com/colaclanth/sstv.git
```

and then install it using this command

```
cd sstv
python setup.py install
```

and now let's decode the audio file&#x20;

<div align="left"><figure><img src="https://1410593648-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FYI2noEqPw69jd0hR7Prp%2Fuploads%2FS2IO1zijnaepejSYZZZP%2Fimage.png?alt=media&amp;token=c4e140be-f0bd-46fc-a589-b65afb1da587" alt=""><figcaption></figcaption></figure></div>

and when it's done open the result.png image&#x20;

<div align="left"><figure><img src="https://1410593648-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FYI2noEqPw69jd0hR7Prp%2Fuploads%2Fkz6YGK7yEZ23i9J12sRL%2Fimage.png?alt=media&amp;token=99b37cd1-8d03-4679-9d11-8baee48a41e9" alt=""><figcaption></figcaption></figure></div>

and this is the password of the zip file

<div align="left"><figure><img src="https://1410593648-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FYI2noEqPw69jd0hR7Prp%2Fuploads%2FBZFZo4edwMxIKaz1u55I%2Fimage.png?alt=media&amp;token=538c552b-4c21-4053-ad81-f5c5d7da9d4f" alt=""><figcaption></figcaption></figure></div>

## <mark style="color:red;">Flag</mark>

**DEFENSYS{FR0M\_TH3\_M00N}**

Greetings from[ <mark style="color:blue;">**Sayonara**</mark>](https://github.com/ismail-arame/)