OPENING QUESTION:

What is metadata and why do we care? (Please discuss).

What is a file header and is that different from meta data?

LEARNING OBJECTIVE:  

• I will learn how to use a specific file editor to analyze an image file during today's class

WORDS FOR TODAY:

I STRONGLY URGE YOU TO START A DECK OF FLASH CARDS HERE

• Innovation: "A new or improved idea, device, product, etc, or the development thereof
• Prototype: "A proof of concept"
• CPU: Central Processing Unit
• Binary: 0's & 1's - Base₂
• Octal: Base₈
• Hexadecimal Base₁₆ - 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F
• Byte: one binary 'word'
• Bit: one binary 'letter' - either a 0 or 1, short for binary digits
• Metadata (information about data in a file that is contained within the file: data about data)
• Abstraction (The difference between what we see/do/interact with a computer and the work actually done by the computer)

WORK O' THE DAY: 

Work with your team to copy the following information into some sort of google document so that it is well formatted and easy to use.

FF	D8	FF	E0	00	10	4A	46	49	46	00	01
44	75	63	6B	79	00	01	00	04	00	00	00
3C	00	00	FF	EE	00	0E	41	64	6F	62	65
00	64	C0	00	00	00	01	FF	DB	00	84	00

Using our favorite ascii table:

And the code/key found HERE, work to confirm the various information about the type of file as well as the particulars for the resulting image file.

 

 

I will post my solution HERE in just a few minutes

I introduced the idea of "Abstraction" yesterday-- notice how I explained it in our "Words of the Day".

As I was researching for today's lesson plan, I found THIS compete explanation of how the following file gets processed by our computers.

It is (needless to say) HIGHLY complex and a MOST excellent example of just how much work our computer does to just (?) display a jpg file. Please keep in mind that someone, somewhere came up with this idea and then had to write the code to do all that work!!!

Please upload the following image and use that key/decoder document I gave you yesterday to determine as much as you can from the 'header' information in that file:

use the https://hexed.it/ website to take a look at the file header. Notice that it is NOT a JFIF so we can't quite use our JFIF key that I gave you yesterday to analyze it (or can we?)

Here is a very tough (college level!) research task for you:

Find the actual format for that header and use it to determine the precise type of file (including version number if possible) and the dimensions of the array that holds the picture data!