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I am trying to split a compressed JPEG bitstream into the 8x8 blocks of the original image. However, I am routinely finding fewer than I know there to be based on the size of the image.

I have narrowed this down to the first row of the image, where the padded edge block (identifiable by its lower mean value) is reached after 65 blocks when the image is 80 blocks across. The end of subsequent rows are then reached after the expected 80 blocks, indicating no further skipped blocks.

Am I simply missing some EOB markers in the first row, or is there a scenario in which some 8x8 blocks are not encoded into the bitstream?

Mike H
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1 Answers1

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If you are decoding a color image, it is very possible that the Cb and Cr components are subsampled so that there are not as many 8x8 blocks as for the Y component.

user3344003
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