animated gif - GIF Data Storage specification question -

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In the GIF specification, here:

I'm having trouble understanding It has two parts:

This specifies the 'LZW minimum code size' which:

This initial number of bits used for LZW code in byte image data Determines, as described in Appendix F.

  1. What does this mean 'the initial number of bits used for the LZW code'?
  2. How do GIFs work in LZW code references? (I think it refers to Limpel-Xavi-Welch).
  3. Where is the elusive 'Apxdix F'? (It is not in the body)

    It also specifies that after a single byte for 'LZW minimum code size', there is a block called 'Image Data', out of which the actual size is unspecified, and it 'Data Sub-blocks'.

    • Does this mean 'data is all-block'?
    • How do I work on the data sub-block size?
    • Is it related to LZW code? If so, how should I explain it?

      Forgive all questions. Thanks for your time.

      As a side-note: Partial answer or answer to any question will also be highly appreciated.

      1. apply the GIF LGW algorithm with a variable size (incremental) code As it has been described. The initial number of 'bits' is the initial size of the code.

      2. This is described in the document you are referring to. List of pixel color codes is compressed (paragraph "a" above the portion you are quoting).

      3. This file contains (at page 30; -) Near the end, simply search for "variable-length-code LZW compression"

      4. "Data sub-block" section 255 contains actual image data or fewer bytes). It may be that

        The linked lists used in image data and extension blocks include a series of sub-blocks, each of these sub-blocks one byte Begins with the number of data bytes coming in sub-block (1 to 255), the series ended by the empty sub-block (one 0 bytes). []

        1. "How do I work to resize the data sub-block?" Look up. This is the first byte of each block.

        2. See above.

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