23 lines
1.2 KiB
Plaintext
23 lines
1.2 KiB
Plaintext
General information - GIF utilities
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Each of the utilities provided in 'util' directory perform some kind of
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filtering, generating new image, or dumping it to a device.
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Because they are not fast, a filter will print (in increasing) order the
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current input image line number, any time it needs to read the input, and
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will print output image line number (in decreasing order) any time it dumps
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out. Other utilities, that only read or write, will always print that half
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the same way (but in increasing order). This is true only for utilities
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that decodes the data. Utilities (like GifPos that only change positions)
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that copies the image as block of compressed data, will print nothing for
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two reasons: they can not idetify line number, and mainly as they are much
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faster.
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Some of the utilities requirs memory in the order of the whole screen, while
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others read one scan line at a time. Each utility DOC file, has entry called
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'Memory Usage' which will be one of: Line (memory required is in the order
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of one scan line), Image (order of biggest image in GIF file), or Screen (order
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of GIF file screen). In all cases, a byte is allocated per pixel, so image of
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320 by 200 pixels will requires ~64k bytes to hold.
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