43 lines
2.4 KiB
Markdown
43 lines
2.4 KiB
Markdown
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# How To Solve
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1) The files 3pm.x84.2 and 3pm.y74.3- are 2 mp3 files that should be reversed (in name and in audio).
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This can be done by the following cmd for example: `sox 3pm.x84.2 file2.84x.mp3 reverse`
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2) Now you will have 2 audio files that describe a huge number that you will need to convert in digits.
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You could use a speech to text convert like the [Vosk-api](https://github.com/alphacep/vosk-api/) to make the task easier.
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To Do so:
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- First convert the mp3 files into wav format:
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`ffmpeg -i file2.84x.mp3 file2.84x.wav`
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- Then install vosk via pip:
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`pip3 install vosk`
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- Then clone the vosk repo and download a english model:
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```
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git clone https://github.com/alphacep/vosk-api
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cd vosk-api/python/example
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wget https://alphacephei.com/vosk/models/vosk-model-en-us-0.22.zip
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unzip vosk-model-en-us-0.22.zip
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mv vosk-model-en-us-0.22.zip model
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python3 ./test_simple.py test.wav > result.json
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```
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Other models could be found [here](https://alphacephei.com/vosk/models).
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- Now You will have a json file with the result that can be found in the json "text" blocks.
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The numbers should be correctly transcribed except for a few of the larger numbers.
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This ones will probably need to be manually corrected.
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- Once you can write a python script that convert large number words into numbers (use a list like [this one](https://en.wikipedia.org/wiki/Names_of_large_numbers) for reference)
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or use a tool with the same capability on the internet (like [this one](https://codebeautify.org/word-to-number-converter)).
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3) After this you will have 2 large numbers of 50 digits.
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You will use this numbers to create a coordinate.
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This can be done by using the reversed file name.
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For example for the file 3pm.y74.3- it will be -3.47y.mp3.
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Which means a negative number with 3 digits before the decimal point,
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48 digits after the decimal point and y means it's the y-coordinate.
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4) if everything is done correctly you should get the coordinate:
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43.568203645634485382241100258703131642483581332123, -116.77239845463438156511102435434249128141577257065
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5) Plug this coordinate into google maps and you will end up on the "Chicken Dinner Rd".
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This you know we will eat a chicken dinner, creating the Flag IGCTF{ChickenDinnerRd}.
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## Flag
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IGCTF{ChickenDinner}
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