Broken GIF test

Warning: opening the files below may crash your browser or computer.

(The GIF specification: original text file, reformatted into HTML.)

normal.gif is an ordinary GIF file:

File Description Valid? Reason
no-palette.gif Like normal.gif but without Global Color Table. valid About Color Tables: Both types of color tables are optional, making it possible for a Data Stream to contain numerous graphics without a color table at all.
no-image.gif Like normal.gif but without Graphic Blocks. valid About Color Tables: The Definition of the GIF Format allows for a Data Stream to contain only the Header, the Logical Screen Descriptor, a Global Color Table and the GIF Trailer.
no-image-no-palette.gif Like normal.gif but without Graphic Blocks or a Color Table. valid Appendix A: Image Descriptor … optional (zero or more occurrences); see also no-palette.gif
minimal.gif 0×0-pixel Logical Screen, no Graphics Blocks, no Color Tables. valid zero-pixel Logical Screen isn't forbidden; see also no-image-no-palette.gif
0x0-image-no-lzw-data.gif Like normal.gif but the image is 0×0 pixels and has no LZW data. invalid Appendix F: Encoders should output a Clear code as the first code of each image data stream.
0x0-image-no-lzw-pixels.gif Like normal.gif but the image is 0×0 pixels and has no pixels in the LZW data (only the clear code and the end code). valid zero-pixel images aren't forbidden; the LZW data starts with the clear code, encodes as many pixels as there are in the image (zero) and ends with the end code; images don't have to cover the entire Logical Screen
no-lzw-data.gif Like normal.gif but without LZW data. invalid Appendix F: Encoders should output a Clear code as the first code of each image data stream.
no-lzw-pixels.gif Like normal.gif but without pixels in the LZW data (only the clear code and the end code). invalid Table Based Image Data: The image data for a table based image consists of a sequence of sub-blocks … containing an index into the active color table, for each pixel in the image.
no-trailer.gif Like normal.gif but without Trailer. invalid Appendix A: Trailer … required (one occurrence)
outside-ls.gif Like normal.gif but the image is outside the Logical Screen. invalid Image Descriptor: Each image must fit within the boundaries of the Logical Screen…

Hexadecimal dumps of the files above:

File Hexadecimal dump
normal.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 00 00 00 00 01 00 01 00 00 02 02 44 01 00 3B
no-palette.gif 47 49 46 38 37 61 01 00 01 00 00 00 00 2C 00 00 00 00 01 00 01 00 00 02 02 44 01 00 3B
no-image.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 3B
no-image-no-palette.gif 47 49 46 38 37 61 01 00 01 00 00 00 00 3B
minimal.gif 47 49 46 38 37 61 00 00 00 00 00 00 00 3B
0x0-image-no-lzw-data.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 00 00 00 00 00 00 00 00 00 02 00 3B
0x0-image-no-lzw-pixels.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 00 00 00 00 00 00 00 00 00 02 01 2C 00 3B
no-lzw-data.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 00 00 00 00 01 00 01 00 00 02 00 3B
no-lzw-pixels.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 00 00 00 00 01 00 01 00 00 02 01 2C 00 3B
no-trailer.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 00 00 00 00 01 00 01 00 00 02 02 44 01 00
outside-ls.gif 47 49 46 38 37 61 01 00 01 00 80 01 00 AA BB CC FF FF FF 2C 01 00 00 00 01 00 01 00 00 02 02 44 01 00 3B

How various programs react to the files:


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