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End Antisemitic Hate
End Antisemitic Hate
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For a specific task (replace an image inside a firmware without any data offset shifting), I need to create a GIF file of size 409x240 pixels of exactly 6449 bytes:

  • offset 0-5: GIF89a (magic string)
  • ...
  • offset 6447-6448: hex 00 3B

When I created such a GIF with, for example MSPaint, the output is ~ 2 KB, which is too small.

Question: is there a way to modify a GIF file to take a larger given size? Can we do null-byte (hex 00) padding near the end of the GIF file? Maybe with ImageMagick, or directly with a HEX editor (I already have one)?

For a specific task (replace an image inside a firmware without any data offset shifting), I need to create a GIF file of size 409x240 of exactly 6449 bytes:

  • offset 0-5: GIF89a (magic string)
  • ...
  • offset 6447-6448: hex 00 3B

When I created such a GIF with, for example MSPaint, the output is ~ 2 KB, which is too small.

Question: is there a way to modify a GIF file to take a larger given size? Can we do null-byte (hex 00) padding near the end of the GIF file? Maybe with ImageMagick, or directly with a HEX editor (I already have one)?

For a specific task (replace an image inside a firmware without any data offset shifting), I need to create a GIF file of size 409x240 pixels of exactly 6449 bytes:

  • offset 0-5: GIF89a (magic string)
  • ...
  • offset 6447-6448: hex 00 3B

When I created such a GIF with, for example MSPaint, the output is ~ 2 KB, which is too small.

Question: is there a way to modify a GIF file to take a larger given size? Can we do null-byte (hex 00) padding near the end of the GIF file? Maybe with ImageMagick, or directly with a HEX editor (I already have one)?

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Basj
Basj
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Make a GIF image with an exact given byte size

For a specific task (replace an image inside a firmware without any data offset shifting), I need to create a GIF file of size 409x240 of exactly 6449 bytes:

  • offset 0-5: GIF89a (magic string)
  • ...
  • offset 6447-6448: hex 00 3B

When I created such a GIF with, for example MSPaint, the output is ~ 2 KB, which is too small.

Question: is there a way to modify a GIF file to take a larger given size? Can we do null-byte (hex 00) padding near the end of the GIF file? Maybe with ImageMagick, or directly with a HEX editor (I already have one)?