Bit plane Compression
The bit plane compression is a lossy data compression
Example:
Explain with a simple example how to encoding and decoding are carried out in bit plane compression. In this example, the MSB (most significant bit) alone is considered and encoded.
Apply bit plane compression and decompression in the following image.
Step1: Obtain binary of the values in the image
Step2: Extract the MSB (most significant bit)
Step3: Rearrange the MSB values such that each row contains 8 columns or 8 bits
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{we have 3x6=18 values but we need 8 columns in each row. It achieved by padding the matrix with zeros in the end in order to form a matrix which has 8 columns in each row.}
Step4: Convert binary in each row to decimal number
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10001001 = 137 10011110 =158 11000000 = 192 |
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Decompression
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Step1: Our compressed data = |
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Convert the decimal values to binary format
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Step2: Remove extra zeros appended to the matrix
Step3: reshape the matrix to size of the original image.
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Step4: Pre allocate a matrix of same size of original image and replace the MSB of each value in the matrix with the bit we decompressed in the previous step.
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10000000 |
00000000 |
00000000 |
00000000 |
10000000 |
00000000 |
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00000000 |
10000000 |
10000000 |
00000000 |
00000000 |
10000000 |
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10000000 |
10000000 |
10000000 |
00000000 |
10000000 |
10000000 |
Step5: Display the final data
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128 |
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128 |
0 |
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128 |
128 |
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128 |
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128 |
128 |
128 |
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128 |
128 |
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Original Image:
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After applying compression and decompression: |
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