Snapshot

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Snapshot

• Mike Huhs
• Sanjay Jhaveri

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Project

• Digital Camera
• User Interface
• Compression and Storage

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Display
Live Video
Shoot Button
Capture
Camera Video
Cursor
Last Picture
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Display
Capture
Click!
Camera Video
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Display
Capture
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Display
Capture
Live Video
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Storage
ZBT Ram 1
ZBT Ram 2
Click!
Your Picture
Compression
Row, Column Address
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Block Diagram
Xvga signals
XVGA
line, column
Data, Address
NTSC Decode
NTSC
Address
Write Control
Read Control
YCrCb
RAM
A/D
RGB
Data
YCrCb
Compressed Image
Controls
Image
RGB Convert
Image Compression
Control
Controls
User Inputs
Mouse
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Image Compression

• 2D Discrete Cosine Transform decomposes image
  into frequency components
• Apply 1D transform to rows and then to columns
• Separately transform 8 x 8 blocks of image
• Eye acts as natural low pass filter
• Only store low frequency components of image

• 180 150 23 12 5 2 1 2
• 130 125 54 22 8 3 5 4
• 77 45 19 4 2 0 3
• 33 21 15 8 4 3 1
• 9 12 5 1 2 5 0
• 13 7 10 8 6 2 2
• 3 4 6 2 1 3 0
• 5 2 8 3 1 2 5 0

8 x 8 pixels
8x8 Input Matrix
8x8 Transform Matrix
1D DCT
1D DCT
Transpose
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Image Compression
data_in
From read module
DCT Memory Control
data_in valid
get picture
From control
delete picture
To read module
data_out
data_out valid
ZBT RAM
idct
idct
idct
dct
dct
dct

• ZBT Ram can store 5-6 pictures

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Possible Additions

• Visual effects such as zoom, rotate, and blur
• Watermarked symbol that appears after processing
  the image

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Questions?